IDRx secures $120m for gastric tumor TKI therapy trials

IDRx, a US-based precision therapeutics company, has successfully raised $120 million in a Series B financing round. The funds will primarily be used for the clinical development of its leading oncology drug candidate, IDRX-42. The financing came from preferred stock investors, including notable US investment firms such as RA Capital Management, Commodore Capital, and Blackstone Multi-Asset Investing.

The primary focus for the newly acquired funds is to support the ongoing Phase I clinical trial and to initiate a pivotal trial for IDRX-42 in patients with gastrointestinal stromal tumors (GIST). IDRX-42 is a selective tyrosine kinase inhibitor (TKI), a class of medications known for their effectiveness in treating various cancers. IDRx obtained the rights to this therapy from Merck KGaA in 2022. The US Food and Drug Administration (FDA) has also granted orphan drug designation to IDRX-42 for the treatment of GIST, providing certain development incentives.

The current Phase I trial, named StrateGIST 1 (NCT05489237), is evaluating the safety and tolerability of IDRX-42 in patients with metastatic and/or surgically unresectable GIST. This trial targets patients who have not responded to Novartis' Gleevec/Glivec (imatinib mesylate) and other approved treatments. Preliminary data released in June indicated promising results, with a 23% objective response rate (ORR) among all participants who had previously undergone a median of four different therapy lines. Notably, patients who received IDRX-42 as a second-line treatment exhibited a 43% ORR, all of which were partial responses.

Commonly observed side effects during the trial were primarily Grade I gastrointestinal symptoms. Three out of 63 patients experienced dose-limited toxicities, but these issues were resolved, and the affected patients opted to continue treatment at reduced dosages.

The success of this financing round and the promising early clinical data underscore the potential of IDRX-42. This candidate adds to IDRx’s growing pipeline, which also includes another TKI, IDRX-73, licensed from Blueprint Medicines.

The landscape for TKIs has shown a mixed performance. While drugs like AstraZeneca’s Tagrisso (osimertinib) have demonstrated significant success in treating non-small cell lung cancer, generating $5.8 billion in sales last year, not all TKIs have fared as well. For instance, Takeda Pharmaceuticals recently announced a voluntary withdrawal of Exkivity (mobocertinib) in the US following the failure of a Phase III trial to meet its primary endpoint.

IDRx’s strategic focus on precision therapeutics and its robust pipeline of TKI inhibitors place it in a compelling position within the oncology drug development sector. The recent funding will not only accelerate the clinical progress of IDRX-42 but also potentially pave the way for new therapeutic options for patients with GIST, a notoriously difficult-to-treat cancer.