GSK has announced that it will be expanding its gastrointestinal (GI) cancer pipeline by acquiring IDRx in a deal worth up to $1.15bn.
The agreement, which includes an upfront payment of $1bn and up to $150m in success-based regulatory approval milestones, gives GSK access to IDRX-42, a highly selective KIT tyrosine kinase inhibitor (TKI) being developed as a first- and second-line therapy for gastrointestinal stromal tumours (GISTs).
GISTs are the most common subtype of soft tissue sarcoma, with up to 120,000 patients diagnosed globally every year.
Approximately 80% of cases are driven by mutations in the KIT gene, and 90% of patients being treated in the first-line develop new KIT mutations that typically lead to relapse with limited therapeutic options. There are currently no approved TKIs that inhibit the full spectrum of clinically relevant primary and secondary mutations in KIT.
IDRX-42 has already demonstrated promising anti-tumour activity and a manageable safety profile in patients with advanced GISTs, according to GSK.
In the ongoing phase 1/1b StrateGIST 1 trial, the objective response rate in the total efficacy evaluable population of patients with second-line or greater GISTs, among all KIT mutation subsets, was 29%. This rose to 53% for patients who had only received one prior line of therapy.
Tony Wood, chief scientific officer, GSK, said: “We are excited by the early data from IDRX-42 and its unique ability to target all clinically relevant KIT mutations present in GISTs, a major gap in the current standard of care. We look forward to accelerating its development in 2025 to redefine treatment.”
Also commenting on the acquisition, IDRx’s chief executive officer, Tim Clackson, said: “We are looking forward to working with GSK to advance IDRX-42 for patients with GISTs, given there have been no major advances to the standard of care for almost 20 years.
“Combining our experience to date with GSK’s expertise in GI cancers, global clinical development capability, and strong commercial presence in oncology will help to accelerate the development of this novel medicine for patients.”
The deal comes just one month after GSK gained an exclusive option to obtain a licence to develop and commercialise Duality Biologics preclinical antibody-drug conjugate, DB-1324, which leverages DualityBio’s Duality Immune Toxin Antibody Conjugate platform against a GI cancer target.