US-based precision therapeutics company IDRx has raised $120m in a Series B financing round to fund the clinical development of its lead oncology candidate, IDRX-42.
The preferred stock financiers included multiple US investment companies such as RA Capital Management, Commodore Capital, and Blackstone Multi-Asset Investing. The company plans to use the proceeds to finance the ongoing Phase I trial and start a pivotal trial evaluating the therapy in patients with gastrointestinal stromal tumours (GIST).
IDRX-42 is a selective tyrosine kinase inhibitor (TKI). IDRx licensed the therapy from Merck KGaA in 2022. It has received an orphan drug designation for the treatment of GIST from the US Food and Drug Administration (FDA).
The ongoing Phase I StrateGIST 1 trial (NCT05489237) is evaluating the safety and tolerability of IDRX-42 in patients with metastatic and/or surgically unresectable GIST after the failure of Novartis’ Gleevec/Glivec (imatinib mesylate) and other approved drugs.
In June, the company reported positive preliminary data from the study showing a 23% objective response rate (ORR) across all patients who received a median of four prior lines of therapy. An ORR of 43% was seen in patients receiving IDRX-42 as a second-line treatment, of which all were partial responses.
Commonly observed side effects were Grade I gastrointestinal symptoms. Three out of the 63 patients experienced dose-limited toxicities, which were resolved, and patients elected to reduce dosages. IDRx’s pipeline also consists of another TKI, IDRX-73, which the company licensed from Blueprint Medicines.
TKIs have been effective in treating various cancers. AstraZeneca‘s Tagrisso (osimertinib) is approved for treating non-small cell lung cancer and generated $5.8bn in sales last year, as per the company’s financials. Gleevec/Glivec is a top 20 highest-grossing drug for Novartis, and raked in $561m in sales in 2023, as per the company’s financials.
It has not been smooth sailing for all TKIs. In October 2023, Takeda Pharmaceutics issued a voluntary withdrawal of Exkivity (mobocertinib) in the US after a confirmatory Phase III trial failed to meet its primary endpoint.
