Organization	12 Months Ended
Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	1. Organization Description of the Business RAPT Therapeutics, Inc. (“RAPT” or the “Company”) is a clinical-stage immunology-based biopharmaceutical company focused on discovering, developing and commercializing novel therapies for patients living with inflammatory and immunological diseases. The Company's lead drug candidate, RPT904, is a half-life extended monoclonal antibody designed to bind free human immunoglobulin E (“IgE”), a key driver of several allergic diseases. The Company’s oncology drug candidate, tivumecirnon, is an oral small-molecule C-C motif chemokine receptor 4 (“CCR4”) antagonist designed to selectively inhibit the migration of immunosuppressive regulatory T cells into tumors. In November 2024, the Company ceased development of zelnecirnon, its small molecule CCR4 antagonist for inflammatory disease. The Company is currently pursuing different novel CCR4 antagonists, which it believes may have improved safety margins. The Company is located in South San Francisco, California. Liquidity and Management Plans The accompanying financial statements have been prepared assuming that the Company will continue as a going concern. Since inception, the Company has incurred net losses and negative cash flows from operations. During the year ended December 31, 2024, the Company incurred a net loss of $129.9 million and used $83.3 million of cash in operations. At December 31, 2024, the Company had cash and cash equivalents and marketable securities of $231.1 million and working capital of $186.9 million. In July, 2024, the Company's board of directors approved a reduction of the Company's workforce to conserve cash resources. The workforce reduction impacted 47 people, or approximately 40% of the Company's headcount. All employees affected by the workforce reduction were eligible to receive, among other things, severance payments and paid COBRA premiums for a specified time period post-termination. The Company incurred $0.9 million in restructuring charges in connection with the workforce reduction, consisting of cash-based expenses related to employee severance payments, benefits and related costs. The Company completed the workforce reduction and all cash payments related to the restructuring during the year ended December 31, 2024. As of December 31, 2024, there were no accrued expenses associated with this workforce reduction. Management plans to continue to incur substantial costs in order to conduct research and development activities and additional capital will be needed to undertake these activities. The Company intends to raise such capital through the issuance of additional equity, borrowings and strategic alliances with other companies. However, if such arrangements are not available at adequate levels or on acceptable terms, the Company would be required to significantly reduce operating expenses and delay or reduce the scope of or eliminate some of its development programs. Management believes that the Company’s current cash and cash equivalents and marketable securities will provide sufficient funds to enable the Company to meet its obligations for at least 12 months from the filing date of this Annual Report on Form 10-K. The Company’s evaluation was based on the facts known as of the date of filing of this Annual Report on Form 10-K.

Organization

12 Months Ended

Dec. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

1. Organization

Description of the Business

RAPT Therapeutics, Inc. (“RAPT” or the “Company”) is a clinical-stage immunology-based biopharmaceutical company focused on discovering, developing and commercializing novel therapies for patients living with inflammatory and immunological diseases. The Company's lead drug candidate, RPT904, is a half-life extended monoclonal antibody designed to bind free human immunoglobulin E (“IgE”), a key driver of several allergic diseases. The Company’s oncology drug candidate, tivumecirnon, is an oral small-molecule C-C motif chemokine receptor 4 (“CCR4”) antagonist designed to selectively inhibit the migration of immunosuppressive regulatory T cells into tumors. In November 2024, the Company ceased development of zelnecirnon, its small molecule CCR4 antagonist for inflammatory disease. The Company is currently pursuing different novel CCR4 antagonists, which it believes may have improved safety margins. The Company is located in South San Francisco, California.

Liquidity and Management Plans

The accompanying financial statements have been prepared assuming that the Company will continue as a going concern. Since inception, the Company has incurred net losses and negative cash flows from operations. During the year ended December 31, 2024, the Company incurred a net loss of $129.9 million and used $83.3 million of cash in operations. At December 31, 2024, the Company had cash and cash equivalents and marketable securities of $231.1 million and working capital of $186.9 million.

In July, 2024, the Company's board of directors approved a reduction of the Company's workforce to conserve cash resources. The workforce reduction impacted 47 people, or approximately 40% of the Company's headcount. All employees affected by the workforce reduction were eligible to receive, among other things, severance payments and paid COBRA premiums for a specified time period post-termination. The Company incurred $0.9 million in restructuring charges in connection with the workforce reduction, consisting of cash-based expenses related to employee severance payments, benefits and related costs. The Company completed the workforce reduction and all cash payments related to the restructuring during the year ended December 31, 2024. As of December 31, 2024, there were no accrued expenses associated with this workforce reduction.

Management plans to continue to incur substantial costs in order to conduct research and development activities and additional capital will be needed to undertake these activities. The Company intends to raise such capital through the issuance of additional equity, borrowings and strategic alliances with other companies. However, if such arrangements are not available at adequate levels or on acceptable terms, the Company would be required to significantly reduce operating expenses and delay or reduce the scope of or eliminate some of its development programs. Management believes that the Company’s current cash and cash equivalents and marketable securities will provide sufficient funds to enable the Company to meet its obligations for at least 12 months from the filing date of this Annual Report on Form 10-K. The Company’s evaluation was based on the facts known as of the date of filing of this Annual Report on Form 10-K.