RAPT Therapeutics is a clinical-stage biopharmaceutical company that has positioned itself at the forefront of the immunology-based therapeutics landscape. With a focus on discovering, developing, and commercializing novel therapies for patients with inflammatory and immunological diseases, RAPT has built a diverse pipeline of drug candidates that hold the potential to address significant unmet medical needs.
Company Background
RAPT Therapeutics, Inc. was incorporated in March 2015 under the name FLX Bio, Inc. The company started as a clinical-stage immunology-based biopharmaceutical company focused on discovering, developing and commercializing novel therapies for patients living with inflammatory and immunological diseases. In May 2019, the company changed its name to RAPT Therapeutics, Inc. At this time, RAPT's lead drug candidate was RPT904, a half-life extended monoclonal antibody designed to bind free human immunoglobulin E (IgE), a key driver of several allergic diseases.
In December 2019, RAPT entered into a collaboration and license agreement with Hanmi Pharmaceutical Co., Ltd., granting Hanmi the exclusive rights to develop, manufacture and commercialize RAPT's oncology drug candidate, tivumecirnon, in Korea, mainland China, Hong Kong, Macau and Taiwan. This deal provided RAPT with upfront and potential milestone payments. The company went public in October 2019, listing its shares on the Nasdaq Global Market under the ticker symbol "RAPT".
Key Drug Candidates
RPT904
One of RAPT Therapeutics' key drug candidates is RPT904, a half-life extended monoclonal antibody designed to bind free human immunoglobulin E (IgE), a critical driver of several allergic diseases. In December 2024, the company entered into an exclusive license agreement with Shanghai Jemincare Pharmaceutical Co., Ltd., granting RAPT worldwide rights, excluding mainland China, Hong Kong, Macau, and Taiwan, to develop and commercialize RPT904. This partnership has the potential to significantly bolster RAPT's efforts to address the large and underserved population of patients suffering from food allergy and chronic spontaneous urticaria (CSU).
Based on a Phase 1 clinical trial conducted by Jemincare, RPT904 demonstrated a median half-life more than two times that of omalizumab (Xolair), the currently approved anti-IgE antibody. The trial also showed deeper and more sustained reduction of free IgE as well as higher total IgE accumulation compared to omalizumab at the same dose. These promising results have led RAPT to plan the clinical development of RPT904 initially in food allergy and chronic spontaneous urticaria (CSU).
Tivumecirnon
RAPT'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 (T reg) into tumors. The company's Phase 2 data for tivumecirnon in combination with pembrolizumab for advanced checkpoint-naïve non-small cell lung cancer (NSCLC) has shown promising results, with greater confirmed objective response rate and progression-free survival than what has historically been demonstrated by pembrolizumab monotherapy.
RAPT holds worldwide rights to tivumecirnon, except for an exclusive license granted to Hanmi Pharmaceutical Ltd. for the Hanmi Territory (Korea, mainland China, Hong Kong, Macau, and Taiwan).
Challenges and Setbacks
In 2024, RAPT faced a setback when it was forced to cease development of its small molecule CCR4 antagonist, zelnecirnon, following a serious adverse event of liver failure in one patient during a Phase 2 clinical trial. This event led to the FDA placing the trials on clinical hold, and after further feedback from the agency, RAPT ultimately decided to terminate the zelnecirnon program. Despite this challenge, the company remains committed to pursuing different novel CCR4 antagonists that it believes may have improved safety margins.
Financials
Financially, RAPT Therapeutics has taken steps to bolster its balance sheet and secure the necessary resources to advance its pipeline. In December 2024, the company announced a $150 million private placement, which is expected to provide the necessary funding to support its ongoing and future development efforts. As of December 31, 2024, RAPT reported cash and cash equivalents, and marketable securities, of $231.1 million, with a working capital position of $186.9 million.
For the full year 2024, RAPT reported a net loss of $129.9 million, compared to a net loss of $116.8 million in the prior year. Research and development expenses increased to $107.2 million, which included a $35 million upfront license fee for RPT904. General and administrative expenses also increased to $28.9 million in 2024. The company's net cash used in operating activities for the year was $83.3 million, while its free cash flow was negative $83.4 million.
In the most recent quarter (Q3 2024), RAPT reported no revenue and a net loss of $53.2 million. The company did not generate any revenue during the year, as it remains focused on the clinical development of its drug candidates.
Liquidity
As of December 31, 2024, RAPT Therapeutics reported a strong liquidity position with $231.1 million in cash and cash equivalents, and marketable securities. This substantial cash reserve, bolstered by the recent $150 million private placement, provides the company with a solid financial foundation to support its ongoing research and development activities, as well as future clinical trials. RAPT believes this funding will be sufficient to fund its planned operations for at least the next 12 months.
Business Overview
RAPT Therapeutics 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 is RPT904, a half-life extended monoclonal antibody designed to bind free human immunoglobulin E (IgE), a key driver of several allergic diseases. RAPT also has an oncology drug candidate, tivumecirnon, which 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.
Currently, RAPT is a small-cap company that only sells in the United States. No scandals, short seller reports, or CEO departures have been reported, indicating a stable management structure and corporate governance.
Future Outlook
Looking ahead, RAPT Therapeutics is well-positioned to continue its pursuit of innovative immunology-based therapies. The company's pipeline, strategic partnerships, and strengthened financial position provide a solid foundation for its future growth and development. However, the inherent risks associated with clinical-stage biopharmaceutical companies, such as the potential for trial failures, regulatory hurdles, and intense competition, will continue to be important factors to monitor.
As RAPT Therapeutics navigates the complexities of the immunology-based therapeutics landscape, its ability to successfully advance its drug candidates through clinical development and ultimately bring them to market will be critical to its long-term success. Investors should closely follow the company's progress, as the potential impact of its innovative therapies on the lives of patients with inflammatory and immunological diseases could be significant.