Forty patients is a small number to move a stock, but the 45% objective response rate BlossomHill Therapeutics reported Monday from its SOLARA trial of BH-30643 is drawing attention precisely because the patients involved have almost nowhere else to go. All 40 had EGFR C797S mutations, the resistance mechanism that emerges after osimertinib fails, and 98% had in fact received osimertinib before enrolling. Getting nearly half of them to respond is the kind of result that makes NSCLC oncologists pay close attention to a Phase 1/2 dataset.
The disease control rate reached 88% (35 of 40 patients), and as of an August 10 efficacy follow-up, 63% of the cohort remained on treatment at a median follow-up of 6.9 months. That durability number matters more than the ORR alone: responses that hold past six months suggest BH-30643 is not just clearing a low bar in a heavily pretreated group but producing something that persists. BlossomHill disclosed the data in a Regulation FD filing tied to a mini-oral presentation at the International Association for the Study of Lung Cancer annual meeting.
BH-30643 is a macrocyclic OMNI-EGFR tyrosine kinase inhibitor, a structural class designed to accommodate the conformational change that C797S forces on the EGFR binding pocket. The mechanism is not novel as a concept, but most TKIs in earlier generations could not bridge C797S with T790M simultaneously; the SOLARA cohort included patients with and without concurrent T790M, and the 45% ORR held across both subgroups. That breadth, if it survives dose-expansion scrutiny, addresses a real clinical headache: oncologists treating post-osimertinib patients often cannot wait for molecular subtyping before deciding on next therapy.
The trial is still enrolling (NCT06706076), and the 6.9-month follow-up is short enough that median duration of response has not matured. The number to track from here is how many of those 25 patients still on treatment maintain response at the 12-month mark, which is where regulators and payers will start asking harder questions about whether a single-arm Phase 1/2 ORR can anchor an accelerated approval submission.
Source link: https://www.sec.gov/Archives/edgar/data/1839970/000119312526391328/d168153d8k.htm
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
