GSK to Acquire IDRx in $1 Billion Deal to Advance Precision Therapeutics for GIST

GSK plc (LSE/NYSE: GSK) has announced its acquisition of IDRx, Inc., a clinical-stage biopharmaceutical company specializing in precision therapeutics for gastrointestinal stromal tumors (GIST). Under the agreement, GSK will pay $1 billion upfront, with an additional $150 million contingent on regulatory approval milestones.

The acquisition includes IDRx's lead molecule, IDRX-42, a highly selective tyrosine kinase inhibitor (TKI) designed to address both primary and secondary KIT mutations that drive tumor progression in GIST. IDRX-42 is being developed as a first- and second-line therapy to improve outcomes for patients with limited current options.

GIST predominantly occurs in the gastrointestinal tract, with 80% of cases driven by activating mutations in the KIT gene. Despite first-line treatments, 90% of patients develop secondary KIT mutations, leading to relapse. Current therapies fail to address the full spectrum of these mutations.

IDRX-42 has demonstrated activity across all clinically relevant KIT mutations, both primary and secondary, setting it apart from existing treatments. Its high selectivity may also improve tolerability, offering a potential best-in-class therapeutic profile.

GSK’s acquisition underscores its commitment to advancing precision medicine and addressing unmet needs in oncology. The addition of IDRX-42 could represent a significant step forward in the treatment landscape for GIST.