<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://www.ptcbio.com/role/AccountsPayableAndAccruedExpenses" xlink:href="ptct-20190930.xsd#AccountsPayableAndAccruedExpenses" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/AccountsPayableAndAccruedExpensesNarrativeDetails" xlink:href="ptct-20190930.xsd#AccountsPayableAndAccruedExpensesNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/AccountsPayableAndAccruedExpensesTables" xlink:href="ptct-20190930.xsd#AccountsPayableAndAccruedExpensesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/Acquisitions" xlink:href="ptct-20190930.xsd#Acquisitions" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/AcquisitionsBusinessAcquisitionProFormaInformationDetails" xlink:href="ptct-20190930.xsd#AcquisitionsBusinessAcquisitionProFormaInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/AcquisitionsNarrativeDetails" xlink:href="ptct-20190930.xsd#AcquisitionsNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/AcquisitionsPreliminaryAllocationOfPurchasePriceDetails" xlink:href="ptct-20190930.xsd#AcquisitionsPreliminaryAllocationOfPurchasePriceDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/AcquisitionsScheduleOfBusinessAcquisitionsDetails" xlink:href="ptct-20190930.xsd#AcquisitionsScheduleOfBusinessAcquisitionsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/AcquisitionsTables" xlink:href="ptct-20190930.xsd#AcquisitionsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/Capitalization" xlink:href="ptct-20190930.xsd#Capitalization" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/CapitalizationNarrativeDetails" xlink:href="ptct-20190930.xsd#CapitalizationNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/CapitalizationTables" xlink:href="ptct-20190930.xsd#CapitalizationTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/CapitalizationWarrantsDetails" xlink:href="ptct-20190930.xsd#CapitalizationWarrantsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/CommitmentsAndContingenciesNarrativeDetails" xlink:href="ptct-20190930.xsd#CommitmentsAndContingenciesNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/Company" xlink:href="ptct-20190930.xsd#Company" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/CompanyNarrativeDetails" xlink:href="ptct-20190930.xsd#CompanyNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/ConsolidatedBalanceSheetsUnaudited" xlink:href="ptct-20190930.xsd#ConsolidatedBalanceSheetsUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/ConsolidatedBalanceSheetsUnauditedParenthetical" xlink:href="ptct-20190930.xsd#ConsolidatedBalanceSheetsUnauditedParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/ConsolidatedStatementsOfCashFlowsUnaudited" xlink:href="ptct-20190930.xsd#ConsolidatedStatementsOfCashFlowsUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/ConsolidatedStatementsOfComprehensiveLossUnaudited" xlink:href="ptct-20190930.xsd#ConsolidatedStatementsOfComprehensiveLossUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/ConsolidatedStatementsOfOperationsUnaudited" xlink:href="ptct-20190930.xsd#ConsolidatedStatementsOfOperationsUnaudited" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/ConsolidatedStatementsOfOperationsUnauditedCalc2" xlink:href="ptct-20190930.xsd#ConsolidatedStatementsOfOperationsUnauditedCalc2" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/ConsolidatedStatementsOfStockholdersEquity" xlink:href="ptct-20190930.xsd#ConsolidatedStatementsOfStockholdersEquity" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/Cover" xlink:href="ptct-20190930.xsd#Cover" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/Debt" xlink:href="ptct-20190930.xsd#Debt" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/DebtConvertibleNotesDetails" xlink:href="ptct-20190930.xsd#DebtConvertibleNotesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/DebtInterestExpenseDetails" xlink:href="ptct-20190930.xsd#DebtInterestExpenseDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/DebtNarrativeDetails" xlink:href="ptct-20190930.xsd#DebtNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/DebtTables" xlink:href="ptct-20190930.xsd#DebtTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecurities" xlink:href="ptct-20190930.xsd#FairValueOfFinancialInstrumentsAndMarketableSecurities" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesAvailableForSaleDetails" xlink:href="ptct-20190930.xsd#FairValueOfFinancialInstrumentsAndMarketableSecuritiesAvailableForSaleDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesFairValueMeasurementInputsAndValuationTechniquesDetails" xlink:href="ptct-20190930.xsd#FairValueOfFinancialInstrumentsAndMarketableSecuritiesFairValueMeasurementInputsAndValuationTechniquesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesHierarchyDetails" xlink:href="ptct-20190930.xsd#FairValueOfFinancialInstrumentsAndMarketableSecuritiesHierarchyDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesMarketableSecuritiesDetails" xlink:href="ptct-20190930.xsd#FairValueOfFinancialInstrumentsAndMarketableSecuritiesMarketableSecuritiesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesNarrativeDetails" xlink:href="ptct-20190930.xsd#FairValueOfFinancialInstrumentsAndMarketableSecuritiesNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesTables" xlink:href="ptct-20190930.xsd#FairValueOfFinancialInstrumentsAndMarketableSecuritiesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesUnrealizedLossPositionsDetails" xlink:href="ptct-20190930.xsd#FairValueOfFinancialInstrumentsAndMarketableSecuritiesUnrealizedLossPositionsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesWarrantsAndSarsDetails" xlink:href="ptct-20190930.xsd#FairValueOfFinancialInstrumentsAndMarketableSecuritiesWarrantsAndSarsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/IntangibleAssetsAndGoodwill" xlink:href="ptct-20190930.xsd#IntangibleAssetsAndGoodwill" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/IntangibleAssetsAndGoodwillFutureAmortizationDetails" xlink:href="ptct-20190930.xsd#IntangibleAssetsAndGoodwillFutureAmortizationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/IntangibleAssetsAndGoodwillNarrativeDetails" xlink:href="ptct-20190930.xsd#IntangibleAssetsAndGoodwillNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/IntangibleAssetsAndGoodwillTables" xlink:href="ptct-20190930.xsd#IntangibleAssetsAndGoodwillTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/Leases" xlink:href="ptct-20190930.xsd#Leases" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/LeasesLeaseCostsDetails" xlink:href="ptct-20190930.xsd#LeasesLeaseCostsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/LeasesLeasePaymentsDetails" xlink:href="ptct-20190930.xsd#LeasesLeasePaymentsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/LeasesLeasePaymentsDetailsCalc2" xlink:href="ptct-20190930.xsd#LeasesLeasePaymentsDetailsCalc2" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/LeasesNarrativeDetails" xlink:href="ptct-20190930.xsd#LeasesNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/LeasesTables" xlink:href="ptct-20190930.xsd#LeasesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/NetLossPerShare" xlink:href="ptct-20190930.xsd#NetLossPerShare" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/NetLossPerShareAntidilutiveDetails" xlink:href="ptct-20190930.xsd#NetLossPerShareAntidilutiveDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/NetLossPerShareNumeratorAndDenominatorDetails" xlink:href="ptct-20190930.xsd#NetLossPerShareNumeratorAndDenominatorDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/NetLossPerShareTables" xlink:href="ptct-20190930.xsd#NetLossPerShareTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/Notes" xlink:href="ptct-20190930.xsd#Notes" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/OtherComprehensiveIncomeLossAndAccumulatedOtherComprehensiveItems" xlink:href="ptct-20190930.xsd#OtherComprehensiveIncomeLossAndAccumulatedOtherComprehensiveItems" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/OtherComprehensiveIncomeLossAndAccumulatedOtherComprehensiveItemsNarrativeDetails" xlink:href="ptct-20190930.xsd#OtherComprehensiveIncomeLossAndAccumulatedOtherComprehensiveItemsNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/OtherComprehensiveIncomeLossAndAccumulatedOtherComprehensiveItemsTables" xlink:href="ptct-20190930.xsd#OtherComprehensiveIncomeLossAndAccumulatedOtherComprehensiveItemsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/RevenueRecognition" xlink:href="ptct-20190930.xsd#RevenueRecognition" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/RevenueRecognitionContractLiabilitiesRollforwardDetails" xlink:href="ptct-20190930.xsd#RevenueRecognitionContractLiabilitiesRollforwardDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/RevenueRecognitionNarrativeDetails" xlink:href="ptct-20190930.xsd#RevenueRecognitionNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/RevenueRecognitionPerformanceObligationsDetails" xlink:href="ptct-20190930.xsd#RevenueRecognitionPerformanceObligationsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/RevenueRecognitionRecognizedRevenueInPeriodDetails" xlink:href="ptct-20190930.xsd#RevenueRecognitionRecognizedRevenueInPeriodDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/RevenueRecognitionTables" xlink:href="ptct-20190930.xsd#RevenueRecognitionTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/StockAwardPlan" xlink:href="ptct-20190930.xsd#StockAwardPlan" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/StockAwardPlanNarrativeDetails" xlink:href="ptct-20190930.xsd#StockAwardPlanNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/StockAwardPlanRestrictedStockDetails" xlink:href="ptct-20190930.xsd#StockAwardPlanRestrictedStockDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/StockAwardPlanShareBaseCompensationDetails" xlink:href="ptct-20190930.xsd#StockAwardPlanShareBaseCompensationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/StockAwardPlanShareBasedCompensationExpenseDetails" xlink:href="ptct-20190930.xsd#StockAwardPlanShareBasedCompensationExpenseDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/StockAwardPlanTables" xlink:href="ptct-20190930.xsd#StockAwardPlanTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/SubsequentEvents" xlink:href="ptct-20190930.xsd#SubsequentEvents" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/SubsequentEventsNarrativeDetails" xlink:href="ptct-20190930.xsd#SubsequentEventsNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPolicies" xlink:href="ptct-20190930.xsd#SummaryOfSignificantAccountingPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesInventoryDetails" xlink:href="ptct-20190930.xsd#SummaryOfSignificantAccountingPoliciesInventoryDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesNarrativeDetails" xlink:href="ptct-20190930.xsd#SummaryOfSignificantAccountingPoliciesNarrativeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesPolicies" xlink:href="ptct-20190930.xsd#SummaryOfSignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesReconciliationOfCashDetails" xlink:href="ptct-20190930.xsd#SummaryOfSignificantAccountingPoliciesReconciliationOfCashDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesTables" xlink:href="ptct-20190930.xsd#SummaryOfSignificantAccountingPoliciesTables" xlink:type="simple" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/AccountsPayableAndAccruedExpenses" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/AccountsPayableAndAccruedExpensesNarrativeDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_15A9AF3234CC52FEBD5A4D1AEF78BBB3" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_46397280FF51591FAF344220CC8962A8" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_15A9AF3234CC52FEBD5A4D1AEF78BBB3" xlink:to="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_46397280FF51591FAF344220CC8962A8" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_AccruedConsultingAndContractedResearchCurrent" xlink:label="loc_ptct_AccruedConsultingAndContractedResearchCurrent_DB374D6B2DD554048AA55D6ED0A5468B" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_15A9AF3234CC52FEBD5A4D1AEF78BBB3" xlink:to="loc_ptct_AccruedConsultingAndContractedResearchCurrent_DB374D6B2DD554048AA55D6ED0A5468B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccruedProfessionalFeesCurrent" xlink:label="loc_us-gaap_AccruedProfessionalFeesCurrent_73326FD45A5F5A7495F00C63DCEB1004" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_15A9AF3234CC52FEBD5A4D1AEF78BBB3" xlink:to="loc_us-gaap_AccruedProfessionalFeesCurrent_73326FD45A5F5A7495F00C63DCEB1004" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_SalesAllowanceAndOtherRelatedCosts" xlink:label="loc_ptct_SalesAllowanceAndOtherRelatedCosts_5C21F84DEAC75D83B1A0ED73B125ED29" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_15A9AF3234CC52FEBD5A4D1AEF78BBB3" xlink:to="loc_ptct_SalesAllowanceAndOtherRelatedCosts_5C21F84DEAC75D83B1A0ED73B125ED29" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaap_AccountsPayableCurrent_E77CB4A32D60555A8365642972F2B0FA" xlink:type="locator" />
    <link:calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_15A9AF3234CC52FEBD5A4D1AEF78BBB3" xlink:to="loc_us-gaap_AccountsPayableCurrent_E77CB4A32D60555A8365642972F2B0FA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherAccruedLiabilitiesCurrent_01A72E0F4F26556E94920500A6808E75" xlink:type="locator" />
    <link:calculationArc order="6" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_15A9AF3234CC52FEBD5A4D1AEF78BBB3" xlink:to="loc_us-gaap_OtherAccruedLiabilitiesCurrent_01A72E0F4F26556E94920500A6808E75" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_SalesRebatesAndRoyaltiesCurrent" xlink:label="loc_ptct_SalesRebatesAndRoyaltiesCurrent_0A4CF099306250DAB6DA870F28090104" xlink:type="locator" />
    <link:calculationArc order="7" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_15A9AF3234CC52FEBD5A4D1AEF78BBB3" xlink:to="loc_ptct_SalesRebatesAndRoyaltiesCurrent_0A4CF099306250DAB6DA870F28090104" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/AccountsPayableAndAccruedExpensesTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/Acquisitions" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/AcquisitionsBusinessAcquisitionProFormaInformationDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/AcquisitionsNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/AcquisitionsPreliminaryAllocationOfPurchasePriceDetails" xlink:type="extended">
    <link:loc xlink:href="ptct-20190930.xsd#ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentAssets" xlink:label="loc_ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentAssets_19eaa01e-344f-cc9d-fe0a-d1b464556e45" xlink:type="locator" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentNetAssets" xlink:label="loc_ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentNetAssets_1eef99dc-20be-139c-534e-d1b4648d96f3" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentAssets_19eaa01e-344f-cc9d-fe0a-d1b464556e45" xlink:to="loc_ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentNetAssets_1eef99dc-20be-139c-534e-d1b4648d96f3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles" xlink:label="loc_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles_cb6e445e-7249-cda9-93ea-27cd989b2a8d" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentNetAssets_1eef99dc-20be-139c-534e-d1b4648d96f3" xlink:to="loc_us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentIntangibles_cb6e445e-7249-cda9-93ea-27cd989b2a8d" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentDeferredIncomeTaxes" xlink:label="loc_ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentDeferredIncomeTaxes_296fd599-ae9a-413b-6262-d1b4652534e0" xlink:type="locator" />
    <link:calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentNetAssets_1eef99dc-20be-139c-534e-d1b4648d96f3" xlink:to="loc_ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentDeferredIncomeTaxes_296fd599-ae9a-413b-6262-d1b4652534e0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GoodwillPurchaseAccountingAdjustments" xlink:label="loc_us-gaap_GoodwillPurchaseAccountingAdjustments_b0f9f2eb-1271-dae0-eeff-bac07e6de02f" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ptct_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentAssets_19eaa01e-344f-cc9d-fe0a-d1b464556e45" xlink:to="loc_us-gaap_GoodwillPurchaseAccountingAdjustments_b0f9f2eb-1271-dae0-eeff-bac07e6de02f" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_05d93b57-3f76-323b-8b13-07dc435183c2" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_37b440e2-656c-b624-0688-b7cf681bf981" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredGoodwillAndLiabilitiesAssumedNet_05d93b57-3f76-323b-8b13-07dc435183c2" xlink:to="loc_us-gaap_Goodwill_37b440e2-656c-b624-0688-b7cf681bf981" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_b6c6e664-e443-6ab8-1587-2187033c3c16" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_89be327a-de9c-56c6-b3d1-10ec3b8a5f9b" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_b6c6e664-e443-6ab8-1587-2187033c3c16" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents_89be327a-de9c-56c6-b3d1-10ec3b8a5f9b" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_2f5c0065-7978-5975-d28d-53a6381a8d42" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_b6c6e664-e443-6ab8-1587-2187033c3c16" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets_2f5c0065-7978-5975-d28d-53a6381a8d42" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_31288939-e5e4-25a4-a69d-b52fe97edfea" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_b6c6e664-e443-6ab8-1587-2187033c3c16" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment_31288939-e5e4-25a4-a69d-b52fe97edfea" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedOtherAssets" xlink:label="loc_ptct_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedOtherAssets_8b72e781-bc49-54f8-d80f-d1b46501af57" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_b6c6e664-e443-6ab8-1587-2187033c3c16" xlink:to="loc_ptct_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedOtherAssets_8b72e781-bc49-54f8-d80f-d1b46501af57" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_583d3161-f22c-2bc8-587e-2ff15f67a984" xlink:type="locator" />
    <link:calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_b6c6e664-e443-6ab8-1587-2187033c3c16" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill_583d3161-f22c-2bc8-587e-2ff15f67a984" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedCurrentLiabilitiesAccountsPayableAndAccruedExpenses" xlink:label="loc_ptct_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedCurrentLiabilitiesAccountsPayableAndAccruedExpenses_a18534df-cef4-abac-429a-d1b465860e4e" xlink:type="locator" />
    <link:calculationArc order="6" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_b6c6e664-e443-6ab8-1587-2187033c3c16" xlink:to="loc_ptct_BusinessCombinationRecognizedIdentifiableAssetsAcquiredandLiabilitiesAssumedCurrentLiabilitiesAccountsPayableAndAccruedExpenses_a18534df-cef4-abac-429a-d1b465860e4e" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_0e2633de-0303-3391-6128-b729f9398b24" xlink:type="locator" />
    <link:calculationArc order="7" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_b6c6e664-e443-6ab8-1587-2187033c3c16" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities_0e2633de-0303-3391-6128-b729f9398b24" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/AcquisitionsScheduleOfBusinessAcquisitionsDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/AcquisitionsTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/Capitalization" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/CapitalizationNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/CapitalizationTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/CapitalizationWarrantsDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/CommitmentsAndContingenciesNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/Company" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/CompanyNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/ConsolidatedBalanceSheetsUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_d7f1ad03-6ed4-706a-15fc-eae794dee33a" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities_44863786-cbc4-bac4-e070-0a1f19314584" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_d7f1ad03-6ed4-706a-15fc-eae794dee33a" xlink:to="loc_us-gaap_Liabilities_44863786-cbc4-bac4-e070-0a1f19314584" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent_30dca50d-a7bd-cff0-949a-3d7ae869c50d" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_44863786-cbc4-bac4-e070-0a1f19314584" xlink:to="loc_us-gaap_LiabilitiesCurrent_30dca50d-a7bd-cff0-949a-3d7ae869c50d" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_9a34fc5e-00bc-420c-8698-6e19b92b8e39" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_30dca50d-a7bd-cff0-949a-3d7ae869c50d" xlink:to="loc_us-gaap_AccountsPayableAndAccruedLiabilitiesCurrent_9a34fc5e-00bc-420c-8698-6e19b92b8e39" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="loc_us-gaap_LongTermDebtCurrent_4909d223-7980-3e65-3e19-5f45ac16b538" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_30dca50d-a7bd-cff0-949a-3d7ae869c50d" xlink:to="loc_us-gaap_LongTermDebtCurrent_4909d223-7980-3e65-3e19-5f45ac16b538" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ContractWithCustomerLiabilityCurrent" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityCurrent_68a2ece1-b79e-558c-a305-f3ccae8c21c3" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_30dca50d-a7bd-cff0-949a-3d7ae869c50d" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityCurrent_68a2ece1-b79e-558c-a305-f3ccae8c21c3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherLiabilitiesCurrent_ebb4c1f8-b5df-aab0-ee90-1e91fd21cf92" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_30dca50d-a7bd-cff0-949a-3d7ae869c50d" xlink:to="loc_us-gaap_OtherLiabilitiesCurrent_ebb4c1f8-b5df-aab0-ee90-1e91fd21cf92" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_BusinessCombinationConsiderationLiabilityDeferredConsiderationPayableCurrent" xlink:label="loc_ptct_BusinessCombinationConsiderationLiabilityDeferredConsiderationPayableCurrent_036128b7-a1e8-8f7b-b20a-f1f319dafe63" xlink:type="locator" />
    <link:calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesCurrent_30dca50d-a7bd-cff0-949a-3d7ae869c50d" xlink:to="loc_ptct_BusinessCombinationConsiderationLiabilityDeferredConsiderationPayableCurrent_036128b7-a1e8-8f7b-b20a-f1f319dafe63" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ContractWithCustomerLiabilityNoncurrent" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityNoncurrent_2bf7259d-4c54-f092-3b62-ad288c59c828" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_44863786-cbc4-bac4-e070-0a1f19314584" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityNoncurrent_2bf7259d-4c54-f092-3b62-ad288c59c828" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_aa2e73c1-d03e-7f76-3502-7a650f99607c" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_44863786-cbc4-bac4-e070-0a1f19314584" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_aa2e73c1-d03e-7f76-3502-7a650f99607c" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_8c850143-cd0c-0f85-9038-e19d8c4f7808" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_44863786-cbc4-bac4-e070-0a1f19314584" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_8c850143-cd0c-0f85-9038-e19d8c4f7808" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_eaedbb6a-5feb-d7b5-74ff-83d9e06de663" xlink:type="locator" />
    <link:calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_44863786-cbc4-bac4-e070-0a1f19314584" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent_eaedbb6a-5feb-d7b5-74ff-83d9e06de663" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DeferredTaxLiabilitiesNoncurrent" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesNoncurrent_aec86b81-11aa-859e-2a56-c42f4bdc8086" xlink:type="locator" />
    <link:calculationArc order="6" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_44863786-cbc4-bac4-e070-0a1f19314584" xlink:to="loc_us-gaap_DeferredTaxLiabilitiesNoncurrent_aec86b81-11aa-859e-2a56-c42f4bdc8086" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_BusinessCombinationConsiderationLiabilityDeferredConsiderationPayable" xlink:label="loc_ptct_BusinessCombinationConsiderationLiabilityDeferredConsiderationPayable_1586be61-ab0a-d2e6-099a-f1f319ed5ca1" xlink:type="locator" />
    <link:calculationArc order="7" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Liabilities_44863786-cbc4-bac4-e070-0a1f19314584" xlink:to="loc_ptct_BusinessCombinationConsiderationLiabilityDeferredConsiderationPayable_1586be61-ab0a-d2e6-099a-f1f319ed5ca1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_4b9904d8-8624-0dbb-a949-29ff2cf808a8" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_d7f1ad03-6ed4-706a-15fc-eae794dee33a" xlink:to="loc_us-gaap_StockholdersEquity_4b9904d8-8624-0dbb-a949-29ff2cf808a8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaap_CommonStockValue_f05ab245-2bd1-7865-e7ed-1461a5a6155f" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_4b9904d8-8624-0dbb-a949-29ff2cf808a8" xlink:to="loc_us-gaap_CommonStockValue_f05ab245-2bd1-7865-e7ed-1461a5a6155f" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaap_AdditionalPaidInCapital_3d5a0ca6-0f59-67e6-adb5-6aecd22b693b" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_4b9904d8-8624-0dbb-a949-29ff2cf808a8" xlink:to="loc_us-gaap_AdditionalPaidInCapital_3d5a0ca6-0f59-67e6-adb5-6aecd22b693b" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_988c1346-b444-a867-fe80-f3aec1443d54" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_4b9904d8-8624-0dbb-a949-29ff2cf808a8" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTax_988c1346-b444-a867-fe80-f3aec1443d54" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_62305d8f-d807-0fe8-d0ab-f2c2b3d03011" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_StockholdersEquity_4b9904d8-8624-0dbb-a949-29ff2cf808a8" xlink:to="loc_us-gaap_RetainedEarningsAccumulatedDeficit_62305d8f-d807-0fe8-d0ab-f2c2b3d03011" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_17ef3f41-42f7-52c0-cba1-93e7e0e1116a" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaap_AssetsCurrent_0b3bd361-d592-2906-279e-2682647fdd27" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_17ef3f41-42f7-52c0-cba1-93e7e0e1116a" xlink:to="loc_us-gaap_AssetsCurrent_0b3bd361-d592-2906-279e-2682647fdd27" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_1de780cc-9607-daa3-0bed-03c88ae94769" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_0b3bd361-d592-2906-279e-2682647fdd27" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_1de780cc-9607-daa3-0bed-03c88ae94769" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_MarketableSecuritiesCurrent" xlink:label="loc_us-gaap_MarketableSecuritiesCurrent_e5ed56be-b332-3e5a-5302-f555a962d258" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_0b3bd361-d592-2906-279e-2682647fdd27" xlink:to="loc_us-gaap_MarketableSecuritiesCurrent_e5ed56be-b332-3e5a-5302-f555a962d258" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_5fd9c643-899e-95d7-aab9-c3a9d6240218" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_0b3bd361-d592-2906-279e-2682647fdd27" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_5fd9c643-899e-95d7-aab9-c3a9d6240218" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReceivablesNetCurrent" xlink:label="loc_us-gaap_ReceivablesNetCurrent_c4de65c9-dd27-7a0a-0b7a-4158d1967739" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_0b3bd361-d592-2906-279e-2682647fdd27" xlink:to="loc_us-gaap_ReceivablesNetCurrent_c4de65c9-dd27-7a0a-0b7a-4158d1967739" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_cc720f44-4c90-5acc-2e7e-b88e80f2af28" xlink:type="locator" />
    <link:calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AssetsCurrent_0b3bd361-d592-2906-279e-2682647fdd27" xlink:to="loc_us-gaap_InventoryNet_cc720f44-4c90-5acc-2e7e-b88e80f2af28" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_4246ec24-1a4c-19dd-57c9-32d4a8e0cbaa" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_17ef3f41-42f7-52c0-cba1-93e7e0e1116a" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_4246ec24-1a4c-19dd-57c9-32d4a8e0cbaa" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_DepositsAndOtherAssetsNoncurrent" xlink:label="loc_ptct_DepositsAndOtherAssetsNoncurrent_cdbf2076-797d-4a98-b2c4-f1f319fef414" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_17ef3f41-42f7-52c0-cba1-93e7e0e1116a" xlink:to="loc_ptct_DepositsAndOtherAssetsNoncurrent_cdbf2076-797d-4a98-b2c4-f1f319fef414" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_8889606b-88fa-2d5e-3fb9-238bccdf9597" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_17ef3f41-42f7-52c0-cba1-93e7e0e1116a" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_8889606b-88fa-2d5e-3fb9-238bccdf9597" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_37b440e2-656c-b624-0688-b7cf681bf981" xlink:type="locator" />
    <link:calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_Assets_17ef3f41-42f7-52c0-cba1-93e7e0e1116a" xlink:to="loc_us-gaap_Goodwill_37b440e2-656c-b624-0688-b7cf681bf981" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/ConsolidatedBalanceSheetsUnauditedParenthetical" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/ConsolidatedStatementsOfCashFlowsUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_50231013-f048-89e7-0e20-ba139224c5f7" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_50231013-f048-89e7-0e20-ba139224c5f7" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_NetIncomeLoss_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Depreciation" xlink:label="loc_us-gaap_Depreciation_848cd271-4e03-8c13-d21d-e6ec9c3916f7" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_Depreciation_848cd271-4e03-8c13-d21d-e6ec9c3916f7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueAdjustmentOfWarrants" xlink:label="loc_us-gaap_FairValueAdjustmentOfWarrants_dcf39713-2bbe-ebf2-2d75-3bc1c2f5ba99" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_FairValueAdjustmentOfWarrants_dcf39713-2bbe-ebf2-2d75-3bc1c2f5ba99" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_64118bb2-1b72-460a-8e47-0026dedd2749" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1_64118bb2-1b72-460a-8e47-0026dedd2749" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_UnrealizedGainLossOnInvestments" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_25f3d0af-ced3-016f-c911-7e8b9a22875d" xlink:type="locator" />
    <link:calculationArc order="5" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_25f3d0af-ced3-016f-c911-7e8b9a22875d" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaidInKindInterest" xlink:label="loc_us-gaap_PaidInKindInterest_bbef1d7c-5ca4-2e69-2da7-2c7dad4e25a3" xlink:type="locator" />
    <link:calculationArc order="6" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_PaidInKindInterest_bbef1d7c-5ca4-2e69-2da7-2c7dad4e25a3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GainLossOnDispositionOfAssets1" xlink:label="loc_us-gaap_GainLossOnDispositionOfAssets1_73cabc52-c416-1a4a-0557-7c2672849759" xlink:type="locator" />
    <link:calculationArc order="7" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_GainLossOnDispositionOfAssets1_73cabc52-c416-1a4a-0557-7c2672849759" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments" xlink:label="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_94f5ae99-7bd8-4f8c-5311-9522abc2f1bd" xlink:type="locator" />
    <link:calculationArc order="8" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_AccretionAmortizationOfDiscountsAndPremiumsInvestments_94f5ae99-7bd8-4f8c-5311-9522abc2f1bd" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_149d6655-b7f8-5049-ef74-296db479f8f9" xlink:type="locator" />
    <link:calculationArc order="9" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_149d6655-b7f8-5049-ef74-296db479f8f9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaap_ShareBasedCompensation_f0b9d825-b0b9-37fd-4d25-9294a8598890" xlink:type="locator" />
    <link:calculationArc order="10" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_ShareBasedCompensation_f0b9d825-b0b9-37fd-4d25-9294a8598890" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ForeignCurrencyTransactionGainLossUnrealized" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossUnrealized_71f47be9-f88f-b596-0981-57b65c400f18" xlink:type="locator" />
    <link:calculationArc order="11" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_ForeignCurrencyTransactionGainLossUnrealized_71f47be9-f88f-b596-0981-57b65c400f18" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_f2b34f8d-2445-12ee-2c68-fa0c5409d5e0" xlink:type="locator" />
    <link:calculationArc order="12" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_IncreaseDecreaseInInventories_f2b34f8d-2445-12ee-2c68-fa0c5409d5e0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_dfcbd6f7-83fa-00c2-bd9e-6c5c1de7d890" xlink:type="locator" />
    <link:calculationArc order="13" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_dfcbd6f7-83fa-00c2-bd9e-6c5c1de7d890" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInReceivables" xlink:label="loc_us-gaap_IncreaseDecreaseInReceivables_a6b55487-86c4-3218-b33b-75029447f45e" xlink:type="locator" />
    <link:calculationArc order="14" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_IncreaseDecreaseInReceivables_a6b55487-86c4-3218-b33b-75029447f45e" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInDepositOtherAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInDepositOtherAssets_83a472e4-c878-e341-48cf-71faca10a716" xlink:type="locator" />
    <link:calculationArc order="15" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_IncreaseDecreaseInDepositOtherAssets_83a472e4-c878-e341-48cf-71faca10a716" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_7c1c3153-d95c-50b8-10ed-a75d1f3d7a68" xlink:type="locator" />
    <link:calculationArc order="16" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_IncreaseDecreaseInAccountsPayableAndAccruedLiabilities_7c1c3153-d95c-50b8-10ed-a75d1f3d7a68" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_d7de2883-fea4-6e7c-2c8b-7fee9aa34369" xlink:type="locator" />
    <link:calculationArc order="17" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities_d7de2883-fea4-6e7c-2c8b-7fee9aa34369" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_8fa19589-0da6-036d-a79e-4bd2fa365a6d" xlink:type="locator" />
    <link:calculationArc order="18" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_ce0d7b63-a366-bc9b-79e1-780981e428fe" xlink:to="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability_8fa19589-0da6-036d-a79e-4bd2fa365a6d" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_0f07a806-a2da-6d18-a7a9-d734fad1f3b0" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_50231013-f048-89e7-0e20-ba139224c5f7" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_0f07a806-a2da-6d18-a7a9-d734fad1f3b0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_0f8df60b-841f-6df5-83c3-e4049d366459" xlink:type="locator" />
    <link:calculationArc order="1" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_0f07a806-a2da-6d18-a7a9-d734fad1f3b0" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_0f8df60b-841f-6df5-83c3-e4049d366459" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquireEquityMethodInvestments" xlink:label="loc_us-gaap_PaymentsToAcquireEquityMethodInvestments_06da844c-6ee0-0b1d-0eaf-6f589c92b21e" xlink:type="locator" />
    <link:calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_0f07a806-a2da-6d18-a7a9-d734fad1f3b0" xlink:to="loc_us-gaap_PaymentsToAcquireEquityMethodInvestments_06da844c-6ee0-0b1d-0eaf-6f589c92b21e" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquireMarketableSecurities" xlink:label="loc_us-gaap_PaymentsToAcquireMarketableSecurities_f6cd34b6-f238-abf8-9b6c-ac9d5fcdd140" xlink:type="locator" />
    <link:calculationArc order="3" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_0f07a806-a2da-6d18-a7a9-d734fad1f3b0" xlink:to="loc_us-gaap_PaymentsToAcquireMarketableSecurities_f6cd34b6-f238-abf8-9b6c-ac9d5fcdd140" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities" xlink:label="loc_us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities_53ccf68b-cae8-c2bb-bc94-e3588a9c5ab9" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_0f07a806-a2da-6d18-a7a9-d734fad1f3b0" xlink:to="loc_us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities_53ccf68b-cae8-c2bb-bc94-e3588a9c5ab9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquireProductiveAssets" xlink:label="loc_us-gaap_PaymentsToAcquireProductiveAssets_a73d82d7-3d54-5ea8-2d2f-c40454b71639" xlink:type="locator" />
    <link:calculationArc order="5" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_0f07a806-a2da-6d18-a7a9-d734fad1f3b0" xlink:to="loc_us-gaap_PaymentsToAcquireProductiveAssets_a73d82d7-3d54-5ea8-2d2f-c40454b71639" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_6abb14d9-7978-302d-af6b-dbfc88f76bf2" xlink:type="locator" />
    <link:calculationArc order="6" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_0f07a806-a2da-6d18-a7a9-d734fad1f3b0" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_6abb14d9-7978-302d-af6b-dbfc88f76bf2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1efd93c0-bb90-2a64-a997-3a70afaa3faa" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_50231013-f048-89e7-0e20-ba139224c5f7" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1efd93c0-bb90-2a64-a997-3a70afaa3faa" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromStockOptionsExercised" xlink:label="loc_us-gaap_ProceedsFromStockOptionsExercised_f73833cd-0af4-c4d5-a7c4-1151269f1da3" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1efd93c0-bb90-2a64-a997-3a70afaa3faa" xlink:to="loc_us-gaap_ProceedsFromStockOptionsExercised_f73833cd-0af4-c4d5-a7c4-1151269f1da3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_0f0975d6-8500-76a0-c74f-5d2f0ed8b620" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1efd93c0-bb90-2a64-a997-3a70afaa3faa" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfCommonStock_0f0975d6-8500-76a0-c74f-5d2f0ed8b620" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromConvertibleDebt" xlink:label="loc_us-gaap_ProceedsFromConvertibleDebt_0ccd9808-af25-d5c0-92fa-163b4b743159" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1efd93c0-bb90-2a64-a997-3a70afaa3faa" xlink:to="loc_us-gaap_ProceedsFromConvertibleDebt_0ccd9808-af25-d5c0-92fa-163b4b743159" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromStockPlans" xlink:label="loc_us-gaap_ProceedsFromStockPlans_b130e83a-7e35-8950-f084-78ccb28f2eab" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1efd93c0-bb90-2a64-a997-3a70afaa3faa" xlink:to="loc_us-gaap_ProceedsFromStockPlans_b130e83a-7e35-8950-f084-78ccb28f2eab" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RepaymentsOfSecuredDebt" xlink:label="loc_us-gaap_RepaymentsOfSecuredDebt_af7d3505-6faf-ba7f-4018-9f6bdebb883a" xlink:type="locator" />
    <link:calculationArc order="5" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1efd93c0-bb90-2a64-a997-3a70afaa3faa" xlink:to="loc_us-gaap_RepaymentsOfSecuredDebt_af7d3505-6faf-ba7f-4018-9f6bdebb883a" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RepaymentsOfDebt" xlink:label="loc_us-gaap_RepaymentsOfDebt_1292ec45-46d1-e31e-9b88-8085df9cd4b2" xlink:type="locator" />
    <link:calculationArc order="6" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_1efd93c0-bb90-2a64-a997-3a70afaa3faa" xlink:to="loc_us-gaap_RepaymentsOfDebt_1292ec45-46d1-e31e-9b88-8085df9cd4b2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_6bd7c3da-2a5b-cbc6-d33a-bb097a23c2f6" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_50231013-f048-89e7-0e20-ba139224c5f7" xlink:to="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_6bd7c3da-2a5b-cbc6-d33a-bb097a23c2f6" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/ConsolidatedStatementsOfComprehensiveLossUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_5c8b3520-1ca2-0a91-0912-70d62831826c" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_5c8b3520-1ca2-0a91-0912-70d62831826c" xlink:to="loc_us-gaap_NetIncomeLoss_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent" xlink:label="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_bab93ab9-d249-c671-e786-575d618bea25" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_5c8b3520-1ca2-0a91-0912-70d62831826c" xlink:to="loc_us-gaap_OtherComprehensiveIncomeAvailableforsaleSecuritiesAdjustmentNetOfTaxPortionAttributableToParent_bab93ab9-d249-c671-e786-575d618bea25" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent" xlink:label="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_71d11517-34f8-505e-4c4b-e25ef3111aee" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax_5c8b3520-1ca2-0a91-0912-70d62831826c" xlink:to="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationAdjustmentNetOfTaxPortionAttributableToParent_71d11517-34f8-505e-4c4b-e25ef3111aee" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/ConsolidatedStatementsOfOperationsUnaudited" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_489b61b6-7c39-240c-7f68-1c1675bca3b7" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_489b61b6-7c39-240c-7f68-1c1675bca3b7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_7a3a9730-2927-590e-4e76-6aeb4157256e" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_489b61b6-7c39-240c-7f68-1c1675bca3b7" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_7a3a9730-2927-590e-4e76-6aeb4157256e" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestIncomeExpenseNonoperatingNet" xlink:label="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_2919f63b-33a2-2107-5264-212ca7a03283" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_489b61b6-7c39-240c-7f68-1c1675bca3b7" xlink:to="loc_us-gaap_InterestIncomeExpenseNonoperatingNet_2919f63b-33a2-2107-5264-212ca7a03283" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_8db01d6d-ae17-523f-94b9-8ab4add4a22e" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_489b61b6-7c39-240c-7f68-1c1675bca3b7" xlink:to="loc_us-gaap_OperatingIncomeLoss_8db01d6d-ae17-523f-94b9-8ab4add4a22e" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_ee6f6897-b14b-45ca-c6e4-4fc17aaf1e37" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_8db01d6d-ae17-523f-94b9-8ab4add4a22e" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_ee6f6897-b14b-45ca-c6e4-4fc17aaf1e37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaap_OperatingExpenses_56807cce-1c23-b2ed-01fd-e029fa0d6e79" xlink:type="locator" />
    <link:calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingIncomeLoss_8db01d6d-ae17-523f-94b9-8ab4add4a22e" xlink:to="loc_us-gaap_OperatingExpenses_56807cce-1c23-b2ed-01fd-e029fa0d6e79" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_3549c1c0-2f2a-e44b-026b-b4042153e489" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_56807cce-1c23-b2ed-01fd-e029fa0d6e79" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_3549c1c0-2f2a-e44b-026b-b4042153e489" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_725ae160-1b15-a075-fa62-729d0bc8cda1" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_56807cce-1c23-b2ed-01fd-e029fa0d6e79" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_725ae160-1b15-a075-fa62-729d0bc8cda1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_ef2ac9e8-006f-b467-3389-9a8ceec4bee5" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_56807cce-1c23-b2ed-01fd-e029fa0d6e79" xlink:to="loc_us-gaap_ResearchAndDevelopmentExpense_ef2ac9e8-006f-b467-3389-9a8ceec4bee5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_89fcc343-1933-1e77-588e-68d1c2f1a04f" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_56807cce-1c23-b2ed-01fd-e029fa0d6e79" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_89fcc343-1933-1e77-588e-68d1c2f1a04f" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset1" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset1_bd3666d6-25ea-ffb7-8a5a-a09208c20299" xlink:type="locator" />
    <link:calculationArc order="5" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OperatingExpenses_56807cce-1c23-b2ed-01fd-e029fa0d6e79" xlink:to="loc_us-gaap_BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationAsset1_bd3666d6-25ea-ffb7-8a5a-a09208c20299" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_666ca9f0-28f1-b21a-025e-36222808a6c3" xlink:type="locator" />
    <link:calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_666ca9f0-28f1-b21a-025e-36222808a6c3" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/ConsolidatedStatementsOfOperationsUnauditedCalc2" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_04997D7B2A21CB7EAA3CFA74CE5611DA_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_04997D7B2A21CB7EAA3CFA74CE5611DA_489b61b6-7c39-240c-7f68-1c1675bca3b7" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_04997D7B2A21CB7EAA3CFA74CE5611DA_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_04997D7B2A21CB7EAA3CFA74CE5611DA_489b61b6-7c39-240c-7f68-1c1675bca3b7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_04997D7B2A21CB7EAA3CFA74CE5611DA_666ca9f0-28f1-b21a-025e-36222808a6c3" xlink:type="locator" />
    <link:calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_NetIncomeLoss_04997D7B2A21CB7EAA3CFA74CE5611DA_e170ce1e-c3a8-e8ee-88b0-37e8dd7b1d11" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_04997D7B2A21CB7EAA3CFA74CE5611DA_666ca9f0-28f1-b21a-025e-36222808a6c3" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/ConsolidatedStatementsOfStockholdersEquity" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/Cover" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/Debt" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/DebtConvertibleNotesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_a2f199ce-3001-c200-d488-633bc54206dc" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_440d49bc-ab70-2673-3639-4fbbaa711932" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_a2f199ce-3001-c200-d488-633bc54206dc" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_440d49bc-ab70-2673-3639-4fbbaa711932" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_UnamortizedDebtIssuanceExpense" xlink:label="loc_us-gaap_UnamortizedDebtIssuanceExpense_133a62ef-4f15-79a5-1ce7-91f3db28df83" xlink:type="locator" />
    <link:calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_a2f199ce-3001-c200-d488-633bc54206dc" xlink:to="loc_us-gaap_UnamortizedDebtIssuanceExpense_133a62ef-4f15-79a5-1ce7-91f3db28df83" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentUnamortizedDiscount" xlink:label="loc_us-gaap_DebtInstrumentUnamortizedDiscount_736d2dab-e6d0-241f-ea81-d597b26683aa" xlink:type="locator" />
    <link:calculationArc order="3" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LongTermDebt_a2f199ce-3001-c200-d488-633bc54206dc" xlink:to="loc_us-gaap_DebtInstrumentUnamortizedDiscount_736d2dab-e6d0-241f-ea81-d597b26683aa" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/DebtInterestExpenseDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestExpenseDebt" xlink:label="loc_us-gaap_InterestExpenseDebt_67350937-b93b-8ace-3db0-138d5fe4c955" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestExpenseDebtExcludingAmortization" xlink:label="loc_us-gaap_InterestExpenseDebtExcludingAmortization_8707b686-ab67-5afd-96da-fedb3cce1b93" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDebt_67350937-b93b-8ace-3db0-138d5fe4c955" xlink:to="loc_us-gaap_InterestExpenseDebtExcludingAmortization_8707b686-ab67-5afd-96da-fedb3cce1b93" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts_149d6655-b7f8-5049-ef74-296db479f8f9" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDebt_67350937-b93b-8ace-3db0-138d5fe4c955" xlink:to="loc_us-gaap_AmortizationOfFinancingCosts_149d6655-b7f8-5049-ef74-296db479f8f9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AmortizationOfDebtDiscountPremium" xlink:label="loc_us-gaap_AmortizationOfDebtDiscountPremium_a4567c23-eef7-473f-21b3-15ac8f57524e" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InterestExpenseDebt_67350937-b93b-8ace-3db0-138d5fe4c955" xlink:to="loc_us-gaap_AmortizationOfDebtDiscountPremium_a4567c23-eef7-473f-21b3-15ac8f57524e" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/DebtNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/DebtTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecurities" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesAvailableForSaleDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_83E57729C5A05B12BF4C2EED6E0D8794" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_276E7B9F2ED8533A9DF79AB51D9632B6" xlink:type="locator" />
    <link:calculationArc order="1" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_83E57729C5A05B12BF4C2EED6E0D8794" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax_276E7B9F2ED8533A9DF79AB51D9632B6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax" xlink:label="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_5DA2C51B35CA52B28BEC847F1B06494C" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_83E57729C5A05B12BF4C2EED6E0D8794" xlink:to="loc_us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax_5DA2C51B35CA52B28BEC847F1B06494C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AvailableForSaleSecuritiesDebtSecurities" xlink:label="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_36CD050FB670516793AB032949679D83" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis_83E57729C5A05B12BF4C2EED6E0D8794" xlink:to="loc_us-gaap_AvailableForSaleSecuritiesDebtSecurities_36CD050FB670516793AB032949679D83" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesFairValueMeasurementInputsAndValuationTechniquesDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesHierarchyDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesMarketableSecuritiesDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesUnrealizedLossPositionsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_65C7785C9BD655CDA468404ED82E7076" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_57A68202D1615B749F521CBD5FD70A83" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_65C7785C9BD655CDA468404ED82E7076" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss_57A68202D1615B749F521CBD5FD70A83" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_41261726B6915AEF919C638AE3C36CF6" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedLossPositionAccumulatedLoss_65C7785C9BD655CDA468404ED82E7076" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss_41261726B6915AEF919C638AE3C36CF6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue_86D0AB3E018855B89B70B5FE9FC61C9F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_14FD9D0AFC165B94BE25612A9549F2DB" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue_86D0AB3E018855B89B70B5FE9FC61C9F" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue_14FD9D0AFC165B94BE25612A9549F2DB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_DED8A54532845105B34D8EB37B95A8E3" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue_86D0AB3E018855B89B70B5FE9FC61C9F" xlink:to="loc_us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue_DED8A54532845105B34D8EB37B95A8E3" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/FairValueOfFinancialInstrumentsAndMarketableSecuritiesWarrantsAndSarsDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/IntangibleAssetsAndGoodwill" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/IntangibleAssetsAndGoodwillFutureAmortizationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_BC37606852345D63B8C639EDFA46C44F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_6E3475372E9E56D9BE855E045B94B10B" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_BC37606852345D63B8C639EDFA46C44F" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_6E3475372E9E56D9BE855E045B94B10B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_C0AC59A2D1D853EEB8E5A0E35C48CF3C" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_BC37606852345D63B8C639EDFA46C44F" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_C0AC59A2D1D853EEB8E5A0E35C48CF3C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_028C4B90B3275C4BBAEF5915CBE35918" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_BC37606852345D63B8C639EDFA46C44F" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_028C4B90B3275C4BBAEF5915CBE35918" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_350958DD55EB5ECEAD8185C982468497" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_BC37606852345D63B8C639EDFA46C44F" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_350958DD55EB5ECEAD8185C982468497" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_FiniteLivedIntangibleAssetsAmortizationExpenseYearFiveAndThereafter" xlink:label="loc_ptct_FiniteLivedIntangibleAssetsAmortizationExpenseYearFiveAndThereafter_8C573AAFA81656F8871E9645D38ABE24" xlink:type="locator" />
    <link:calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_BC37606852345D63B8C639EDFA46C44F" xlink:to="loc_ptct_FiniteLivedIntangibleAssetsAmortizationExpenseYearFiveAndThereafter_8C573AAFA81656F8871E9645D38ABE24" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/IntangibleAssetsAndGoodwillNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/IntangibleAssetsAndGoodwillTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/Leases" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/LeasesLeaseCostsDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/LeasesLeasePaymentsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1c2cd15f-6a97-015f-b126-1d0a0750698b" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_48abcf97-737b-2b2c-8a8c-c74539d0b215" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1c2cd15f-6a97-015f-b126-1d0a0750698b" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear_48abcf97-737b-2b2c-8a8c-c74539d0b215" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_9b040bc1-f43c-735d-05f7-679f319d2bb6" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1c2cd15f-6a97-015f-b126-1d0a0750698b" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo_9b040bc1-f43c-735d-05f7-679f319d2bb6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_2f0ec234-4f20-7099-efb3-3c0ab4d024dd" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1c2cd15f-6a97-015f-b126-1d0a0750698b" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree_2f0ec234-4f20-7099-efb3-3c0ab4d024dd" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_1ed751b1-5f94-4f6f-41e9-ef873c9f2bab" xlink:type="locator" />
    <link:calculationArc order="4" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1c2cd15f-6a97-015f-b126-1d0a0750698b" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour_1ed751b1-5f94-4f6f-41e9-ef873c9f2bab" xlink:type="arc" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_LesseeOperatingLeaseLiabilityPaymentsDueYearFiveandThereafter" xlink:label="loc_ptct_LesseeOperatingLeaseLiabilityPaymentsDueYearFiveandThereafter_80c39aeb-cc9a-fa23-366f-f1f319f500e6" xlink:type="locator" />
    <link:calculationArc order="5" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_1c2cd15f-6a97-015f-b126-1d0a0750698b" xlink:to="loc_ptct_LesseeOperatingLeaseLiabilityPaymentsDueYearFiveandThereafter_80c39aeb-cc9a-fa23-366f-f1f319f500e6" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/LeasesLeasePaymentsDetailsCalc2" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_9FAFCFB9C1D40277589AD1A07748902D_1c2cd15f-6a97-015f-b126-1d0a0750698b" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_9FAFCFB9C1D40277589AD1A07748902D_07815ffa-512a-3133-dcbb-38e09d2626b9" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_9FAFCFB9C1D40277589AD1A07748902D_1c2cd15f-6a97-015f-b126-1d0a0750698b" xlink:to="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount_9FAFCFB9C1D40277589AD1A07748902D_07815ffa-512a-3133-dcbb-38e09d2626b9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingLeaseLiability" xlink:label="loc_us-gaap_OperatingLeaseLiability_9FAFCFB9C1D40277589AD1A07748902D_b983c2d8-8318-0a7e-1a5c-6ab2933f7be5" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue_9FAFCFB9C1D40277589AD1A07748902D_1c2cd15f-6a97-015f-b126-1d0a0750698b" xlink:to="loc_us-gaap_OperatingLeaseLiability_9FAFCFB9C1D40277589AD1A07748902D_b983c2d8-8318-0a7e-1a5c-6ab2933f7be5" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/LeasesNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/LeasesTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/NetLossPerShare" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/NetLossPerShareAntidilutiveDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/NetLossPerShareNumeratorAndDenominatorDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/NetLossPerShareTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/Notes" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/OtherComprehensiveIncomeLossAndAccumulatedOtherComprehensiveItems" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/OtherComprehensiveIncomeLossAndAccumulatedOtherComprehensiveItemsNarrativeDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_E4919C8585B45273ACBF7EF759C43E7A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_5090AA13610951C49C8DFE7C32C54967" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_E4919C8585B45273ACBF7EF759C43E7A" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax_5090AA13610951C49C8DFE7C32C54967" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent_18BEDEE198ED5CD48C58C9E740484B53" xlink:type="locator" />
    <link:calculationArc order="2" weight="-1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_E4919C8585B45273ACBF7EF759C43E7A" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodNetOfTaxAttributableToParent_18BEDEE198ED5CD48C58C9E740484B53" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/OtherComprehensiveIncomeLossAndAccumulatedOtherComprehensiveItemsTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/RevenueRecognition" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/RevenueRecognitionContractLiabilitiesRollforwardDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/RevenueRecognitionNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/RevenueRecognitionPerformanceObligationsDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/RevenueRecognitionRecognizedRevenueInPeriodDetails" xlink:type="extended">
    <link:loc xlink:href="ptct-20190930.xsd#ptct_NetProductSales" xlink:label="loc_ptct_NetProductSales_C884001180EA5E6683027E19C3B0473F" xlink:type="locator" />
    <link:loc xlink:href="ptct-20190930.xsd#ptct_ContractWithCustomerLiabilityAmountsRecognizedBeginningOfMeasurementPeriod" xlink:label="loc_ptct_ContractWithCustomerLiabilityAmountsRecognizedBeginningOfMeasurementPeriod_5B3A3B78B1D45DA0964CA1079E9544C2" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ptct_NetProductSales_C884001180EA5E6683027E19C3B0473F" xlink:to="loc_ptct_ContractWithCustomerLiabilityAmountsRecognizedBeginningOfMeasurementPeriod_5B3A3B78B1D45DA0964CA1079E9544C2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod" xlink:label="loc_us-gaap_ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod_8ACEC63C16C6571FA8753C890C5C77FD" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ptct_NetProductSales_C884001180EA5E6683027E19C3B0473F" xlink:to="loc_us-gaap_ContractWithCustomerPerformanceObligationSatisfiedInPreviousPeriod_8ACEC63C16C6571FA8753C890C5C77FD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ContractWithCustomerLiabilityRevenueRecognized" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_5164BCDAFDAE56638B56CA7803D5A21D" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_ptct_NetProductSales_C884001180EA5E6683027E19C3B0473F" xlink:to="loc_us-gaap_ContractWithCustomerLiabilityRevenueRecognized_5164BCDAFDAE56638B56CA7803D5A21D" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/RevenueRecognitionTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/StockAwardPlan" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/StockAwardPlanNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/StockAwardPlanRestrictedStockDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/StockAwardPlanShareBaseCompensationDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/StockAwardPlanShareBasedCompensationExpenseDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/StockAwardPlanTables" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/SubsequentEvents" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/SubsequentEventsNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPolicies" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesInventoryDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_52A51F7BB2135269A97EAC827BC5015C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InventoryWorkInProcess" xlink:label="loc_us-gaap_InventoryWorkInProcess_576B5802E3845989A379BC91B3918C9A" xlink:type="locator" />
    <link:calculationArc order="1" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_52A51F7BB2135269A97EAC827BC5015C" xlink:to="loc_us-gaap_InventoryWorkInProcess_576B5802E3845989A379BC91B3918C9A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InventoryFinishedGoods" xlink:label="loc_us-gaap_InventoryFinishedGoods_55D201BAFA27572388DA5CB7BFE845EC" xlink:type="locator" />
    <link:calculationArc order="2" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_52A51F7BB2135269A97EAC827BC5015C" xlink:to="loc_us-gaap_InventoryFinishedGoods_55D201BAFA27572388DA5CB7BFE845EC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InventoryRawMaterials" xlink:label="loc_us-gaap_InventoryRawMaterials_30DEA815D73B56ECA74B33BC624C667B" xlink:type="locator" />
    <link:calculationArc order="3" weight="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item" xlink:from="loc_us-gaap_InventoryNet_52A51F7BB2135269A97EAC827BC5015C" xlink:to="loc_us-gaap_InventoryRawMaterials_30DEA815D73B56ECA74B33BC624C667B" xlink:type="arc" />
  </link:calculationLink>
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesNarrativeDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesPolicies" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesReconciliationOfCashDetails" xlink:type="extended" />
  <link:calculationLink xlink:role="http://www.ptcbio.com/role/SummaryOfSignificantAccountingPoliciesTables" xlink:type="extended" />
</link:linkbase>
