AbbVie agreed to a staged transaction that gives it an exclusive right to acquire Kestrel Therapeutics for up to $1.45 billion, contingent on milestones tied to Kestrel’s oral pan-RAS inhibitor, KST-6051. The deal was announced as Kestrel said dosing began in a Phase 1 trial for patients with KRAS-driven solid tumors. AbbVie will fund the KST-6051 program under the arrangement, with the companies saying the collaboration will explore broader KRAS mutation coverage than earlier highly specific strategies. For Kestrel, the agreement provides near-term development capital tied to clinical and regulatory progress. The market impact is direct for pan-RAS competitors: AbbVie is signaling it wants a next wave of KRAS pathway coverage beyond single-mutation approaches, where efficacy and durability remain the gating factors.