IDRx secures $120M for pivotal study after early KIT inhibitor data

Following a compelling data presentation at the American Society of Clinical Oncology (ASCO) annual meeting in June, IDRx has secured a $120-million series B funding to further the clinical development of its KIT inhibitor for gastrointestinal stromal tumors (GIST). This funding will support ongoing efforts to advance their therapy, designated as IDRX-42, through clinical trials.

The Phase I/Ib StrateGIST 1 study is currently enrolling patients with KIT-mutant GIST. Participants are receiving doses of IDRX-42 ranging from 120 mg once-daily to 600 mg twice-daily. During an oral presentation at ASCO, IDRx shared promising data from this study. Specifically, the experimental therapy demonstrated an objective response rate (ORR) of 23% among 66 evaluable patients, who had previously undergone a median of four different lines of treatment. Notably, among the 14 patients receiving IDRX-42 as a second-line treatment, six experienced a partial response, translating to an ORR of 43%.

CEO Tim Clackson explained that IDRX-42 was specifically engineered to address the dual challenges of treatment resistance and adverse events caused by off-target effects, which are common limitations of existing tyrosine kinase inhibitors (TKIs). This innovative approach aims to offer a more effective and safer treatment option for patients.

The recent $120-million funding will enable IDRx to initiate a pivotal study of IDRX-42 in second-line GIST patients next year. This is particularly significant as it comes on the heels of IDRX-42 receiving fast track designation from the FDA. According to Clackson, there has been no new treatment option for first- and second-line GIST patients in over 15 years, highlighting the potential impact of this development.

The financing round was led by RA Capital Management, Commodore Capital, and Blackstone Multi-Asset Investing. New investors, including Rock Springs Capital, also contributed, alongside existing backers such as Andreessen Horowitz (a16z) Bio + Health, Casdin Capital, Nextech Invest Ltd., Forge Life Science Partners, and Merck KGaA, which is a strategic partner of IDRx. It is worth noting that a16z and Casdin co-led the company's $122-million series A funding round in 2022.

IDRx's advancements in the treatment of GIST, supported by robust financial backing and strategic partnerships, underscore the company's commitment to addressing unmet needs in oncology. The forthcoming pivotal study of IDRX-42 holds promise for improving outcomes for GIST patients who have limited treatment options, potentially transforming the landscape of GIST therapy.