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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 | 9 Months Ended
--- | --- | --- | --- | --- | ---
Sep. 08, 2021 | Jul. 03, 2017 | Nov. 30, 2022 | Jan. 31, 2022 | Nov. 30, 2020 | Oct. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Feb. 28, 2017 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  | $ 9,477 | $ 15,419 | $ 34,313 | $ 46,872
Mayo Clinic [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  |  | 2,200 |  | 2,200 |
PSCA (MB-105) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  |  | 500 |  | 500 |
HER2 (MB 103) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  |  | 3,000 |  | 3,000 |
CD20 (MB-106) [Member] | Fred Hutchinson Cancer Center [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  |  | 8,400 |  | 8,400 |
ST. Jude - XSCID [Member] | St. Jude Children's Research Hospital [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Total reimbursement payments made |  |  |  |  |  |  |  |  |  | 3,500 |  | 3,500 |
IL13Ra2 CAR and (C134) [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  | $ 600 |  |  | $ 300 |  |  |  |  |  |  |
Sponsored Research and Clinical Trial Agreements [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  | 364 | 1,836 | 3,739 | 4,884
Sponsored Research and Clinical Trial Agreements [Member] | Mayo Clinic [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  |  | 269 | 551 | 731
Sponsored Research and Clinical Trial Agreements [Member] | CD123 (MB-102) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Contribution per patient |  |  |  |  |  |  |  |  | $ 100 |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  | 23 | 63 | 23 | 165
Sponsored Research and Clinical Trial Agreements [Member] | IL13Ra2 (MB-101) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Contribution toward patient costs |  |  |  |  |  |  |  |  | $ 100 |  |  |  |
Contribution per patient |  |  |  |  |  | 100 |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  | 180 | 192 | 817 | 654
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 |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Contribution toward patient costs |  |  |  |  |  |  |  |  |  |  |  | 200 |
Sponsored Research and Clinical Trial Agreements [Member] | CS1 (MB-104) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  |  | 187 | 188 | 287
Total reimbursement payments made |  |  |  |  |  |  |  |  |  | 2,200 |  | 2,200 |
Sponsored Research and Clinical Trial Agreements [Member] | CS1 (MB-104) [Member] | City of Hope National Medical Center ("COH") [Member] | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Milestones payable |  |  |  |  |  |  |  | $ 2,400 |  |  |  |  |
Sponsored Research and Clinical Trial Agreements [Member] | PSCA (MB-105) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  |  | 27 | 44 | 77
Sponsored Research and Clinical Trial Agreements [Member] | PSCA (MB-105) [Member] | City of Hope National Medical Center ("COH") [Member] | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Milestones payable |  |  |  |  |  | $ 2,300 |  |  |  |  |  |  |
Sponsored Research and Clinical Trial Agreements [Member] | HER2 (MB 103) [Member] | City of Hope National Medical Center ("COH") [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  |  | 691 | 0 | 1,233
Sponsored Research and Clinical Trial Agreements [Member] | HER2 (MB 103) [Member] | City of Hope National Medical Center ("COH") [Member] | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Milestones payable |  |  |  |  |  |  | $ 3,000 |  |  |  |  |  |
Sponsored Research and Clinical Trial Agreements [Member] | CD20 (MB-106) [Member] | Fred Hutchinson Cancer Center [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Milestones payable |  | $ 5,300 |  |  |  |  |  |  |  |  |  |  |
Additional milestone payments |  |  |  | $ 2,200 | $ 1,800 |  |  |  |  |  |  |  |
Contribution toward patient costs |  |  |  |  | $ 800 |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  | 142 | 132 | 1,239 | 978
Sponsored Research and Clinical Trial Agreements [Member] | CD20 (MB-106) [Member] | Fred Hutchinson Cancer Center [Member] | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Additional milestone payments |  |  |  | $ 9,300 |  |  |  |  |  |  |  |  |
Sponsored Research and Clinical Trial Agreements [Member] | RAG1 SCID (MB-110) [Member] | Leiden University Medical Centre [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
License, Clinical Trial and Sponsored Research Agreements |  |  |  |  |  |  |  |  |  |  |  |  |
Agreement term | 5 years |  |  |  |  |  |  |  |  |  |  |  |
Research and development expense |  |  |  |  |  |  |  |  |  | $ 125 | $ 92 | $ 349 | $ 357
Annual maintenance fee payable | $ 500 |  |  |  |  |  |  |  |  |  |  |  |

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