License and Collaboration Agreements	12 Months Ended
Dec. 31, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
License and Collaboration Agreements	4. License and Collaboration Agreements Clinical Trial Collaboration and Supply Agreements with MSD International GmbH In February 2018, we entered into a clinical collaboration with MSD International GmbH ("MSDIG"), to evaluate IO102 in combination with KEYTRUDA® (pembrolizumab) in first-line treatment of patients with metastatic non-small cell lung cancer. Under the terms of the collaboration with MSDIG, we will conduct an international Phase 1/2 study to evaluate a combination therapy of IO102 and KEYTRUDA®. We will sponsor the clinical trials and MSDIG will provide KEYTRUDA® to be used in the clinical trials free of charge. We and MSDIG will be responsible for our own internal costs and expenses to support the study and we shall bear all other costs associated with conducting the study, including costs of providing IO102 for use in the study. The rights to the data from the clinical trials will be shared by us and MSDIG and we will maintain global commercial rights to IO102. In September 2021, we entered into a clinical collaboration with MSDIG and MSD International Business GmbH (MSDIB), another affiliate of Merck, (collectively, "MSD") to evaluate IO102-IO103 in combination with KEYTRUDA® versus KEYTRUDA® alone in treatment of patients with metastatic (advanced) melanoma. Under the terms of the collaboration with MSD, we will conduct an international Phase 3 study to evaluate a combination therapy of IO102-IO103 and KEYTRUDA®. We will sponsor the clinical trials and MSD will provide KEYTRUDA® to be used in the clinical trials free of charge. We and MSD will be responsible for our own internal costs and expenses to support the study and we shall bear all other costs associated with conducting the study, including costs of providing IO102-IO103 for use in the study. The rights to the data from the clinical trials will be shared by us and MSD and we will maintain global commercial rights to IO102-IO103. In December 2021, we entered into a clinical collaboration with MSD to evaluate IO102-IO103 in combination with KEYTRUDA® in previously untreated patients with three different tumor types— metastatic non-small cell lung cancer (NSCLC), squamous cell carcinoma of the head and neck (SCCHN), and metastatic urothelial bladder cancer (UBC). Under the terms of the collaboration with MSD, we will conduct an international Phase 2 study to evaluate a combination therapy of IO102-IO103 and KEYTRUDA®. We will sponsor the clinical trials and MSD will provide KEYTRUDA® to be used in the clinical trials free of charge. We and MSD will be responsible for our own internal costs and expenses to support the study and we shall bear all other costs associated with conducting the study, including costs of providing IO102-IO103 for use in the study. The rights to the data from the clinical trials will be shared by us and MSD and we will maintain global commercial rights to IO102-IO103. Agreements with Herlev Hospital We have a number of existing agreements with the Herlev University Hospital in Denmark (“Herlev”) for scientific and other support of our ongoing development activities. In January 2021, we entered into an additional agreement with Herlev regarding the payment of specific services whereupon in addition to any consideration payable by us to Herlev pursuant to the existing agreements we were required to pay a fee to Herlev of DKK 5.0 million (approximately $0.8 million) in the event of an initial public offering or other liquidity event whereby all or substantially all of the value of the Company is realized in consideration for cash. The Company consummated its IPO in November 2021, resulting in this payment to Herlev becoming payable. Additionally, upon the completion of the IPO, the Company was obligated to make payments to Herlev in the aggregate amount of DKK 13.2 million, (which is approximately $2.1 million based on the exchange rate of DKK 6.54 to one U.S. dollar on December 31, 2021). We expensed $2.9 million to research and development expense for the year ended December 31, 2021, which was subsequently paid in February 2022.

License and Collaboration Agreements

12 Months Ended

Dec. 31, 2021

Organization Consolidation And Presentation Of Financial Statements [Abstract]

4. License and Collaboration Agreements

Clinical Trial Collaboration and Supply Agreements with MSD International GmbH

In February 2018, we entered into a clinical collaboration with MSD International GmbH ("MSDIG"), to evaluate IO102 in combination with KEYTRUDA® (pembrolizumab) in first-line treatment of patients with metastatic non-small cell lung cancer. Under the terms of the collaboration with MSDIG, we will conduct an international Phase 1/2 study to evaluate a combination therapy of IO102 and KEYTRUDA®. We will sponsor the clinical trials and MSDIG will provide KEYTRUDA® to be used in the clinical trials free of charge. We and MSDIG will be responsible for our own internal costs and expenses to support the study and we shall bear all other costs associated with conducting the study, including costs of providing IO102 for use in the study. The rights to the data from the clinical trials will be shared by us and MSDIG and we will maintain global commercial rights to IO102.

In September 2021, we entered into a clinical collaboration with MSDIG and MSD International Business GmbH (MSDIB), another affiliate of Merck, (collectively, "MSD") to evaluate IO102-IO103 in combination with KEYTRUDA® versus KEYTRUDA® alone in treatment of patients with metastatic (advanced) melanoma. Under the terms of the collaboration with MSD, we will conduct an international Phase 3 study to evaluate a combination therapy of IO102-IO103 and KEYTRUDA®. We will sponsor the clinical trials and MSD will provide KEYTRUDA® to be used in the clinical trials free of charge. We and MSD will be responsible for our own internal costs and expenses to support the study and we shall bear all other costs associated with conducting the study, including costs of providing IO102-IO103 for use in the study. The rights to the data from the clinical trials will be shared by us and MSD and we will maintain global commercial rights to IO102-IO103.

In December 2021, we entered into a clinical collaboration with MSD to evaluate IO102-IO103 in combination with KEYTRUDA® in previously untreated patients with three different tumor types— metastatic non-small cell lung cancer (NSCLC), squamous cell carcinoma of the head and neck (SCCHN), and metastatic urothelial bladder cancer (UBC). Under the terms of the collaboration with MSD, we will conduct an international Phase 2 study to evaluate a combination therapy of IO102-IO103 and KEYTRUDA®. We will sponsor the clinical trials and MSD will provide KEYTRUDA® to be used in the clinical trials free of charge. We and MSD will be responsible for our own internal costs and expenses to support the study and we shall bear all other costs associated with conducting the study, including costs of providing IO102-IO103 for use in the study. The rights to the data from the clinical trials will be shared by us and MSD and we will maintain global commercial rights to IO102-IO103.

Agreements with Herlev Hospital

We have a number of existing agreements with the Herlev University Hospital in Denmark (“Herlev”) for scientific and other support of our ongoing development activities. In January 2021, we entered into an additional agreement with Herlev regarding the payment of specific services whereupon in addition to any consideration payable by us to Herlev pursuant to the existing agreements we were required to pay a fee to Herlev of DKK 5.0 million (approximately $0.8 million) in the event of an initial public offering or other liquidity event whereby all or substantially all of the value of the Company is realized in consideration for cash. The Company consummated its IPO in November 2021, resulting in this payment to Herlev becoming payable. Additionally, upon the completion of the IPO, the Company was obligated to make payments to Herlev in the aggregate amount of DKK 13.2 million, (which is approximately $2.1 million based on the exchange rate of DKK 6.54 to one U.S. dollar on December 31, 2021). We expensed $2.9 million to research and development expense for the year ended December 31, 2021, which was subsequently paid in February 2022.