Research and Development Arrangements	3 Months Ended
Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Research and Development Arrangements	Note 11. Research and Development Arrangements The Column Group and Catalyst4 Agreement On June 7, 2024, the Company entered into a collaboration agreement with The Column Group-Neuro, LP (“TCG”), an investor in the Company, and Catalyst4, Inc. (“Catalyst4”), a limited partner in TCG’s neuroscience fund. Under the terms of the agreement, Catalyst4 will pay the Company an aggregate payment of $25.0 million over the next five years to perform upfront research and development on drug discovery or drug development programs for Parkinson’s Disease. In addition, the Company is required to pay up to $50.0 million to Catalyst4 upon the achievement of a certain regulatory milestone. In the event Eikon sells or licenses programs to a third party to develop, the Company is required to pay Catalyst4 a mid-double digit percentage of all payments received, up to $50.0 million in the aggregate across all such programs. The Company has received $10.0 million from Catalyst4 for future services, which was recorded in other non-current liabilities on its condensed balance sheet as of March 31, 2026. Clinical Trial Collaboration and Supply Agreements with MSD The Company entered into a clinical trial collaboration and supply agreement (the “MSD Agreement”) with MSD International Business GmbH (“MSD”), for three separate studies: (i) the Phase 2/3 registrational study of EIK1001 in patients with advanced melanoma (dated August 1, 2024); (ii) the Phase 1/2 clinical trial of EIK1005 in patients with advanced solid tumors (dated December 3, 2025); and (iii) the Phase 2/3 registrational study of EIK1001 in patients with non-small cell lung cancer (dated December 5, 2025). Pursuant to the MSD Agreements, the Company and MSD agreed to collaborate on these clinical trials evaluating the safety and efficacy of its compounds in combination with MSD’s compound, pembrolizumab. Under the MSD Agreements, the Company acts as the sponsor of the clinical trials at its own costs and MSD has agreed to supply to the Company, at its own cost, pembrolizumab for use in such trials. Pursuant to the MSD Agreements, the Company and MSD must each use commercially reasonable efforts to supply the Company’s applicable compounds for use in the portions of the clinical trials in which patients are intended to receive pembrolizumab either alone or in combination with one or more treatments, in accordance with the applicable study protocol. The Company recognizes costs incurred for the EIK clinical trial as research and development expenses within the statement of operations and comprehensive loss. The Company and MSD will jointly own all clinical data and results generated from the portion of the clinical trials involving the combination of the Company’s compound and pembrolizumab. The Company owns all clinical data and results generated from all portions of these clinical trials that involve its compound alone or in combination with other treatments that are not pembrolizumab, and MSD owns all clinical data and results generated from the portions of the clinical trial involving pembrolizumab alone or in combination with other treatments that are not the Company’s compound (the “MSD clinical data”). The Company may use MSD clinical data solely to evaluate the safety or performance of the combination or to register its compound in the combination. The MSD Agreements will each expire upon the delivery of a results memorandum and final report of the portions of the respective trial where patients receive pembrolizumab to MSD, unless earlier terminated, or, in the case of the Phase 2/3 trials, if the Phase 3 portion of the clinical trial is not initiated. MSD may terminate the supply agreement for a particular clinical trial if the Company does not initiate the trial for the combination within one year from the effective date of the respective MSD Agreement. Further, MSD may terminate an MSD agreement and the supply of pembrolizumab immediately if (i) MSD notifies the Company that it believes that pembrolizumab is being used unsafely in the trial and (ii) either MSD believes such matter is not reasonably capable of being remedied, or if the Company fails to remedy promptly such issue to MSD’s reasonable satisfaction. Either the Company or MSD may terminate an MSD agreement for a breach of the agreement, for patient safety, or due to regulatory authority objections or actions. Further, either party may also terminate an MSD agreement if such party determines, in its sole discretion, to withdraw any applicable regulatory approval for its respective compound, or to discontinue development of its respective compound for medical, scientific, or legal reasons.

Research and Development Arrangements

3 Months Ended

Mar. 31, 2026

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Note 11. Research and Development Arrangements

The Column Group and Catalyst4 Agreement

On June 7, 2024, the Company entered into a collaboration agreement with The Column Group-Neuro, LP (“TCG”), an investor in the Company, and Catalyst4, Inc. (“Catalyst4”), a limited partner in TCG’s neuroscience fund.

Under the terms of the agreement, Catalyst4 will pay the Company an aggregate payment of $25.0 million over the next five years to perform upfront research and development on drug discovery or drug development programs for Parkinson’s Disease. In addition, the Company is required to pay up to $50.0 million to Catalyst4 upon the achievement of a certain regulatory milestone. In the event Eikon sells or licenses programs to a third party to develop, the Company is required to pay Catalyst4 a mid-double digit percentage of all payments received, up to $50.0 million in the aggregate across all such programs.

The Company has received $10.0 million from Catalyst4 for future services, which was recorded in other non-current liabilities on its condensed balance sheet as of March 31, 2026.

Clinical Trial Collaboration and Supply Agreements with MSD

The Company entered into a clinical trial collaboration and supply agreement (the “MSD Agreement”) with MSD International Business GmbH (“MSD”), for three separate studies: (i) the Phase 2/3 registrational study of EIK1001 in patients with advanced melanoma (dated August 1, 2024); (ii) the Phase 1/2 clinical trial of EIK1005 in patients with advanced solid tumors (dated December 3, 2025); and (iii) the Phase 2/3 registrational study of EIK1001 in patients with non-small cell lung cancer (dated December 5, 2025). Pursuant to the MSD Agreements, the Company and MSD agreed to collaborate on these clinical trials evaluating the safety and efficacy of its compounds in combination with MSD’s compound, pembrolizumab. Under the MSD Agreements, the Company acts as the sponsor of the clinical trials at its own costs and MSD has agreed to supply to the Company, at its own cost, pembrolizumab for use in such trials. Pursuant to the MSD Agreements, the Company and MSD must each use commercially reasonable efforts to supply the Company’s applicable compounds for use in the portions of the clinical trials in which patients are intended to receive pembrolizumab either alone or in combination with one or more treatments, in accordance with the applicable study protocol. The Company recognizes costs incurred for the EIK clinical trial as research and development expenses within the statement of operations and comprehensive loss.

The Company and MSD will jointly own all clinical data and results generated from the portion of the clinical trials involving the combination of the Company’s compound and pembrolizumab. The Company owns all clinical data and results generated from all portions of these clinical trials that involve its compound alone or in combination with other treatments that are not pembrolizumab, and MSD owns all clinical data and results generated from the portions of the clinical trial involving pembrolizumab alone or in combination with other treatments that are not the Company’s compound (the “MSD clinical data”). The Company may use MSD clinical data solely to evaluate the safety or performance of the combination or to register its compound in the combination.

The MSD Agreements will each expire upon the delivery of a results memorandum and final report of the portions of the respective trial where patients receive pembrolizumab to MSD, unless earlier terminated, or, in the case of the Phase 2/3 trials, if the Phase 3 portion of the clinical trial is not initiated. MSD may terminate the supply agreement for a particular clinical trial if the Company does not initiate the trial for the combination within one year from the effective date of the respective MSD Agreement. Further, MSD may terminate an MSD agreement and the supply of pembrolizumab immediately if (i) MSD notifies the Company that it believes that pembrolizumab is being used unsafely in the trial and (ii) either MSD believes such matter is not reasonably capable of being remedied, or if the Company fails to remedy promptly such issue to MSD’s reasonable satisfaction. Either the Company or MSD may terminate an MSD agreement for a breach of the agreement, for patient safety, or due to regulatory authority objections or actions. Further, either party may also terminate an MSD agreement if such party determines, in its sole discretion, to withdraw any applicable regulatory approval for its respective compound, or to discontinue development of its respective compound for medical, scientific, or legal reasons.