The Company	6 Months Ended
The Company	Jun. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company	The Company PTC Therapeutics, Inc. (the “Company” or “PTC”) is a science-driven global biopharmaceutical company focused on the discovery, development and commercialization of clinically-differentiated medicines that provide benefits to patients with rare disorders. The Company’s ability to globally commercialize products is the foundation that drives its continued investment in a robust diversified pipeline of transformative medicines and its mission to provide access to best-in-class treatments for patients who have an unmet medical need. The Company’s strategy is to bring best-in-class therapies with differentiated clinical benefit to patients affected by rare disorders and to leverage its global commercial infrastructure to maximize value for its patients and other stakeholders. The Company has two products, Translarna™ (ataluren) and Emflaza™ (deflazacort), for the treatment of Duchenne muscular dystrophy, or DMD, a rare, life threatening disorder. Translarna has marketing authorization in the European Economic Area (the “EEA”) for the treatment of nonsense mutation Duchenne muscular dystrophy, or nmDMD, in ambulatory patients aged 2 years and older and in Brazil for the treatment of nmDMD in ambulatory patients aged 5 years and older, subject to annual renewal and other conditions. In June 2020, the Committee for Medicinal Products for Human Use (the "CHMP") of the European Medicines Agency ("EMA") recommended to remove the statement “efficacy has not been demonstrated in non-ambulatory patients” from the product label for Translarna. The CHMP's opinion is subject to final approval by the European Commission, which is typically provided within two months of the CHMP's recommendation. Emflaza is approved in the United States for the treatment of DMD in patients two years and older. The Company has a pipeline of gene therapy product candidates for rare monogenic diseases that affect the central nervous system (“CNS”) including PTC-AADC for the treatment of Aromatic L-Amino Acid Decarboxylase, or AADC deficiency, a rare CNS disorder arising from reductions in the enzyme AADC that results from mutations in the dopa decarboxylase gene. The Company is preparing a biologics license application ("BLA") for PTC-AADC for the treatment of AADC deficiency in the United States and it anticipates initiating the BLA submission to the United States Food and Drug Administration ("FDA") in the second half of 2020. In January 2020, the Company submitted a marketing authorization application ("MAA") to the EMA for PTC-AADC for the treatment of AADC deficiency in the EEA, and the Company expects an opinion from the CHMP in the first quarter of 2021. The Company holds the rights for the commercialization of Tegsedi™ (inotersen) and Waylivra™ (volanesorsen) for the treatment of rare diseases in countries in Latin America and the Caribbean pursuant to the Company’s Collaboration and License Agreement with Akcea Therapeutics, Inc. (“Akcea”). Tegsedi has received marketing authorization in the United States, the European Union (the “EU”) and Brazil for the treatment of stage 1 or stage 2 polyneuropathy in adult patients with hereditary transthyretin amyloidosis, or hATTR amyloidosis. Waylivra has received marketing authorization in the EU for the treatment of familial chylomicronemia syndrome, or FCS. The Company filed for marketing authorization for Waylivra for the treatment of FCS with ANVISA, the Brazilian health regulatory authority, in June 2020 and, subject to potential delays in the review process related to the COVID-19 pandemic, expects a regulatory decision on approval from ANVISA in 2021. The Company also has a spinal muscular atrophy ("SMA") collaboration with F. Hoffman-La Roche Ltd and Hoffman-La Roche Inc., referred to collectively as Roche, and the Spinal Muscular Atrophy Foundation ("SMA Foundation"). The lead compound in the SMA program is risdiplam (RG7916, RO7034067). Roche submitted an NDA for risdiplam to the FDA in the fourth quarter of 2019. In April 2020, the FDA extended the Prescription Drug User Fee Act ("PDUFA") date for a decision from May 24, 2020 to August 24, 2020 as a result of additional data that Roche submitted, including comprehensive data from the Sunfish part 2 study. Risdiplam is expected to be indicated in the United States for SMA type 1, 2 and 3 patients, if approved. Roche anticipates submitting an MAA for risdiplam in the EEA imminently. On October 25, 2019, the Company completed the acquisition of substantially all of the assets of BioElectron Technology Corporation (“BioElectron”), a Delaware corporation, including certain compounds that the Company has begun to develop as part of its Bio-e platform, (the “Asset Acquisition”) pursuant to an asset purchase agreement by and between the Company and BioElectron, dated October 1, 2019 (the “Asset Acquisition Agreement”). The transaction was accounted for as an asset acquisition. The two most advanced molecules in the Company's Bio-e platform are vatiquinone, formerly known as PTC743, and PTC857. The Company expects to initiate a potential registrational Phase 2 placebo-controlled trial of vatiquinone in approximately 60 children with mitochondrial disease and associated refractory epilepsy in the third quarter of 2020. The Company also expects to initiate a potential registrational Phase 3 trial of vatiquinone in approximately 100 patients with Friedrich ataxia in the fourth quarter of 2020. In the second quarter of 2020, the Company initiated a Phase 1 trial in healthy volunteers to evaluate the safety and pharmacology of PTC857. The Company expects data from the single ascending dose and multiple ascending dose studies from the Phase 1 trial to be available by the end of 2020. In addition, the Company has a pipeline of product candidates and discovery programs that are in early clinical, pre-clinical and research and development stages focused on the development of new treatments for multiple therapeutic areas, including rare diseases and oncology. The Company’s marketing authorization for Translarna in the EEA is subject to annual review and renewal by the European Commission following reassessment by the EMA of the benefit-risk balance of the authorization, which the Company refers to as the annual EMA reassessment. This marketing authorization is further subject to the specific obligation to conduct and submit the results of a multi-center, randomized, double-blind, 18-month, placebo-controlled trial, followed by an 18-month open-label extension, according to an agreed protocol, in order to confirm the efficacy and safety of Translarna. The final report on the trial and open-label extension is to be submitted by the Company to the EMA by the end of the third quarter of 2022. The Company refers to the trial and open-label extension together as Study 041. The marketing authorization in the EEA was last renewed in June 2020 and is effective, unless extended, through August 5, 2021. The renewal was based on the Company’s commitment to conduct Study 041 and the totality of the clinical data available from its trials and studies of Translarna for the treatment of nmDMD, including the safety and efficacy results of the Phase 2b and Phase 3 clinical trials. The primary efficacy endpoint was not achieved in either trial within the pre-specified level of statistical significance. Translarna is an investigational new drug in the United States. During the first quarter of 2017, the Company filed a New Drug Application, or NDA, over protest with the FDA, for which the FDA granted a standard review. In October 2017, the Office of Drug Evaluation I of the FDA issued a complete response letter for the NDA, stating that it was unable to approve the application in its current form. In response, the Company filed a formal dispute resolution request with the Office of New Drugs of the FDA. In February 2018, the Office of New Drugs of the FDA denied the Company's appeal of the Complete Response Letter. In its response, the Office of New Drugs recommended a possible path forward for the ataluren NDA submission based on the accelerated approval pathway. This would involve a re-submission of an NDA containing the current data on effectiveness of ataluren with new data to be generated on dystrophin production in nmDMD patients’ muscles. The Company intends to follow the FDA’s recommendation and will collect, using newer technologies via procedures and methods that the Company designed, such dystrophin data in a new study, Study 045, which the Company initiated in the fourth quarter of 2018. As a result of intermittent discontinuations of certain elective procedures at the Company's clinical trial site in response to the COVID-19 pandemic, the Company's expected completion of Study 45 has been delayed as certain patients still require final study muscle biopsies. Once the clinical trial site is open for the necessary procedures and patients are able to safely travel to the site, the Company expects to be able to complete the final biopsies and the data from Study 045 would be available thereafter, followed by a potential re-submission of an NDA. Additionally, should a re-submission of an NDA receive accelerated approval, the Office of New Drugs stated that Study 041, which is currently enrolling, could serve as the confirmatory post-approval trial required in connection with the accelerated approval framework. On August 23, 2018, the Company completed its acquisition of Agilis Biotherapeutics, Inc., or Agilis, pursuant to an Agreement and Plan of Merger, dated as of July 19, 2018 (the “Merger Agreement”), by and among the Company, Agility Merger Sub, Inc., a Delaware corporation and the Company's wholly owned, indirect subsidiary, Agilis and, solely in its capacity as the representative, agent and attorney-in-fact of the equityholders of Agilis, Shareholder Representative Services LLC, (the "Merger"). Upon the closing of the Merger, the Company paid to Agilis equityholders total upfront consideration comprised of $49.2 million in cash and 3,500,907 shares of the Company’s common stock (the “Closing Stock Consideration”). The Closing Stock Consideration was determined by dividing $150.0 million by the volume-weighted average price per share of the Company’s common stock on the Nasdaq Global Select Market for the 10 consecutive trading-day period ending on the second trading-day immediately preceding the closing of the Merger. Agilis equityholders are entitled to receive contingent payments from the Company based on the achievement of certain development, regulatory and net sales milestones as well as based upon a percentage of net sales of certain products. On April 29, 2020, the Company, certain of the former equity holders of Agilis, and, for the limited purposes set forth in the agreement, Shareholder Representative Services LLC, entered into a Rights Exchange Agreement (the “Rights Exchange Agreement”). Pursuant to the Rights Exchange Agreement, the Company issued 2,821,176 shares of its common stock (the “Common Stock Consideration”) and paid $36.9 million (the “Cash Consideration”), in the aggregate, to such former equity holders of Agilis (the “Participating Rightholders”) in exchange for the cancellation and forfeiture by the Participating Rightholders of their rights to receive certain milestone-based contingent payments under the Merger Agreement, pursuant to which the Company completed the Merger. Pursuant to the terms of the Rights Exchange Agreement, the Participating Rightholders have canceled and forfeited their rights under the Merger Agreement to receive (i) $174.0 million, in the aggregate, of potential milestone payments based on the achievement of certain regulatory milestones and (ii) $37.6 million, in the aggregate, of $40.0 million in development milestone payments that would have been due upon the passing of the second anniversary of the closing of the Merger, regardless of whether the milestones are achieved. The Rights Exchange Agreement has no effect on the Merger Agreement other than to provide for the cancellation and forfeiture of the Participating Rightholders’ rights to receive $211.6 million, in the aggregate, of the milestone payments described above. As a result, all other rights and obligations under the Merger Agreement remain in effect pursuant to their terms, including the Company’s obligation to pay up to an aggregate maximum amount of $22.4 million upon the achievement of certain development milestones (representing the remaining portion of potential development milestone payments for which rights were not canceled and forfeited pursuant to the Rights Exchange Agreement after deducting the $37.6 million for which rights were canceled and forfeited pursuant to the Rights Exchange Agreement from the $40.0 million in development milestone payments that are due upon the passing of the second anniversary of the closing of the Merger), up to an aggregate maximum amount of $361.0 million upon the achievement of certain regulatory milestones (representing the remaining portion of potential regulatory milestone payments for which rights were not canceled and forfeited pursuant to the Rights Exchange Agreement), up to a maximum aggregate amount of $150.0 million upon the achievement of certain net sales milestones and a percentage of annual net sales for Friedreich ataxia and Angelman syndrome during specified terms, ranging from 2% to 6%, pursuant to the terms of the Merger Agreement. Refer to Note 5 for further details regarding the Rights Exchange Agreement. On May 29, 2020, the Company completed its acquisition of Censa Pharmaceuticals, Inc., (“Censa”) pursuant to an Agreement and Plan of Merger, dated as of May 5, 2020, (the "Censa Merger Agreement"), by and among the Company, Hydro Merger Sub, Inc., the Company's wholly owned, indirect subsidiary, and, solely in its capacity as the representative, agent and attorney-in-fact of the securityholders of Censa, Shareholder Representative Services LLC (the "Censa Merger"). The transaction was accounted for as an asset acquisition. In connection with the Censa Merger, the Company acquired PTC923 (formerly known as CNSA-001), which is being pursued as a possible treatment for orphan metabolic diseases associated with defects in the tetrahydrobiopterin biochemical pathways, including phenylketonuria ("PKU"). Refer to Note 3 for further details. As of June 30, 2020, the Company had an accumulated deficit of approximately $1,484.8 million. The Company has financed its operations to date primarily through the private offerings in September 2019 of 1.50% convertible senior notes due 2026 and in August 2015 of 3.00% convertible senior notes due 2022 (see Note 11), public offerings of common stock in February 2014, October 2014, April 2018, January 2019, and September 2019, "at the market offerings" of its common stock, its initial public offering of common stock in June 2013, private placements of its convertible preferred stock, collaborations, bank debt, the Company's credit and security agreement (the "Credit Agreement"), with MidCap Financial Trust, or MidCap Financial, as administrative agent and MidCap Financial and other certain institutions as lenders thereto (see Note 11), grant funding and clinical trial support from governmental and philanthropic organizations and patient advocacy groups in the disease area addressed by the Company’s product candidates. Since 2014, the Company has also relied on revenue generated from net sales of Translarna for the treatment of nmDMD in territories outside of the United States, and since May 2017, the Company has generated revenue from net sales of Emflaza for the treatment of DMD in the United States. The Company expects that cash flows from the sales of its products, together with the Company's cash, cash equivalents and marketable securities, will be sufficient to fund its operations for at least the next twelve months.