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Clinical Trial and Sponsored Research Agreements (City of Hope - Sponsored Research and Clinical Trial Agreements) (Narrative) (Details) - USD ($) $ in Thousands |  |  | 1 Months Ended | 3 Months Ended
--- | --- | --- | --- | ---
Sep. 08, 2021 | Jul. 03, 2017 | Jan. 31, 2022 | Nov. 30, 2020 | Oct. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Feb. 28, 2017 | Mar. 31, 2022 | Mar. 31, 2021
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | $ 16,289 | $ 11,618
Mayo Clinic [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  | 900 |
PSCA (MB-105) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  | 300 |
HER2 (MB 103) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  | 2,200 |
CD20 (MB-106) [Member] | Fred Hutchinson Cancer Research Center [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  | 5,200 |
ST. Jude - XSCID [Member] | St. Jude Children's Research Hospital [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  | 2,700 |
Sponsored Research and Clinical Trial Agreements [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | 1,592 | 1,842
Sponsored Research and Clinical Trial Agreements [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | 0 | 0
Sponsored Research and Clinical Trial Agreements [Member] | Mayo Clinic [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | 231 | 0
Sponsored Research and Clinical Trial Agreements [Member] | CD123 (MB-102) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Contribution per patient |  |  |  |  |  |  |  | $ 100 |  |
Research and development expense |  |  |  |  |  |  |  |  | 51 | 205
Sponsored Research and Clinical Trial Agreements [Member] | CS1 (MB-104) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | 50 | 175
Total reimbursement payments made |  |  |  |  |  |  |  |  | 1,500 |
Sponsored Research and Clinical Trial Agreements [Member] | CS1 (MB-104) [Member] | City of Hope National Medical Center ("COH") [Member] | Maximum |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Milestones payable |  |  |  |  |  |  | $ 2,400 |  |  |
Sponsored Research and Clinical Trial Agreements [Member] | IL13Ra2 (MB-101) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Contribution toward patient costs |  |  |  |  |  |  |  | $ 100 |  |
Contribution per patient |  |  |  |  | $ 100 |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | 228 | 514
Annual maintenance fee payable |  |  |  |  | 200 |  |  |  |  |
Sponsored Research and Clinical Trial Agreements [Member] | IL13Ra2 (MB-101) [Member] | City of Hope National Medical Center ("COH") [Member] | Maximum |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Contribution toward patient costs |  |  |  |  |  |  |  |  | 200 |
Sponsored Research and Clinical Trial Agreements [Member] | PSCA (MB-105) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | 22 | 50
Sponsored Research and Clinical Trial Agreements [Member] | PSCA (MB-105) [Member] | City of Hope National Medical Center ("COH") [Member] | Maximum |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Milestones payable |  |  |  |  | $ 2,300 |  |  |  |  |
Sponsored Research and Clinical Trial Agreements [Member] | HER2 (MB 103) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | 271 | 123
Sponsored Research and Clinical Trial Agreements [Member] | HER2 (MB 103) [Member] | City of Hope National Medical Center ("COH") [Member] | Maximum |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Milestones payable |  |  |  |  |  | $ 3,000 |  |  |  |
Sponsored Research and Clinical Trial Agreements [Member] | CD20 (MB-106) [Member] | Fred Hutchinson Cancer Research Center [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Milestones payable |  | $ 5,300 |  |  |  |  |  |  |  |
Additional milestone payments |  |  | $ 2,200 | $ 1,800 |  |  |  |  |  |
Contribution toward patient costs |  |  |  | $ 800 |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | 488 | 671
Sponsored Research and Clinical Trial Agreements [Member] | CD20 (MB-106) [Member] | Fred Hutchinson Cancer Research Center [Member] | Maximum |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Additional milestone payments |  |  | $ 9,300 |  |  |  |  |  |  |
Sponsored Research and Clinical Trial Agreements [Member] | ST. Jude - XSCID [Member] | St. Jude Children's Research Hospital [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | 124 | 104
Sponsored Research and Clinical Trial Agreements [Member] | RAG1 SCID (MB-110) [Member] | Leiden University Medical Centre [Member] |  |  |  |  |  |  |  |  |  |
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] |  |  |  |  |  |  |  |  |  |
Agreement term | 5 years |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  | $ 127 | $ 0
Annual maintenance fee payable | $ 500 |  |  |  |  |  |  |  |  |

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