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Commitments and Contingencies - Additional Information (Details) - USD ($) |  |  |  |  | 3 Months Ended
--- | --- | --- | --- | --- | ---
Mar. 31, 2022 | Jun. 22, 2021 | Mar. 01, 2021 | Jan. 08, 2021 | Mar. 31, 2022 | Mar. 31, 2021
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |
Operating leases expiry year |  |  |  |  | 2025 |
Minimum lease payment | $ 382,000 |  |  |  | $ 382,000 |
Operating lease, weighted average discount rate | 9.00% |  |  |  | 9.00% |
Operating lease, weighted average remaining term | 2 years 9 months 25 days |  |  |  | 2 years 9 months 25 days |
Rent expense |  |  |  |  | $ 60,000 | $ 50,000
Lorem Vascular Pte Ltd [Member] |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |
Compensatory damages and operational |  | $ 6,000,000 |  |  |  |
Pre-clinical Research Study Obligations [Member] |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |
Contractual obligation | $ 0 |  |  |  | 0 |
Pre-clinical Research Study Obligations [Member] | Lorem Vascular Pte Ltd [Member] |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |
Litigation settlement, expense |  |  |  |  | 0 |
Charlottesville [Member] |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |
Lessee, operating lease, term of contract |  |  | 12 months |  |  |
Lessee, operating lease, existence of option to extend [true false] |  |  | true |  |  |
Lessee, operating lease, option to extend |  |  | The Charlottesville Lease has a term of 12 months and is renewable for four additional one-year periods. |  |  |
Lessee, operating lease, renewal term |  |  | 1 year |  |  |
Minimum lease payment |  |  | $ 30,000 |  |  |
Annual increase in lease rate |  |  | 3.00% |  |  |
Lease commencement date |  |  | Apr. 01, 2021 |  |  |
Operating leases, expiration date |  |  | Mar. 31, 2023 |  |  |
Medidata Solutions, Inc. [Member] | Services Agreement [Member] |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |
Statement of work, term | 6 months |  |  |  |  |
Managed services fees payable | $ 1,450,000 |  |  |  | 1,450,000 |
Contingent managed services fee | $ 150,000 |  |  |  | $ 150,000 |
Piramal Pharma Solutions, Inc. [Member] |  |  |  |  |  |
Recorded Unconditional Purchase Obligation [Line Items] |  |  |  |  |  |
Master service agreement date |  |  |  | Jan. 08, 2021 |  |
Master services agreement initial term |  |  |  | 5 years |  |
Master services agreement terms, Description |  |  |  |  | The MSA has a term of five years and will automatically renew for successive one-year terms unless either party notifies the other no later than six months prior to the original term or any additional terms of its intention to not renew the MSA. The Company has the right to terminate the MSA for convenience upon thirty days’ prior written notice. |

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