Cardiff Oncology doubles down on onvansertib

Cardiff Oncology has shifted the development strategy for its PLK1 inhibitor onvansertib in Ras-mutated colorectal cancer: the second-line phase 2 Onsemble trial has been discontinued, and instead a new first-line programme is being initiated. This follows disappointing data from a phase 1/2 dose-finding study, which in its most recent iteration at Asco-GI 2022 had shown a worrying deterioration of confirmed responses. Moreover, Onsemble had only started dosing patients five months ago. The new programme will kick off with the initiation of the phase 2 CRDF-004 trial, evaluating two onvansertib doses plus chemo and Avastin, versus standard of care alone. Data are expected in mid-2024, and depending on these Cardiff plans to start the phase 3 CRDF-005 trial with registrational intent, saying the FDA has agreed to ORR as the basis for accelerated approval, with PFS and a trend in OS needed for full approval.