Cardiff Oncology provides update on discontinued ONSEMBLE trial data

Cardiff Oncology provided a clinical update on the first release of data from its second-line RAS-mutated metastatic colorectal cancer, or mCRC, ONSEMBLE trial. Although the Phase 2 ONSEMBLE trial was discontinued as part of the company’s shift to a first-line mCRC program, it enrolled 23 patients randomized across three arms prior to closing the trial to new enrollment. The 23 enrolled patients continued treatment per protocol. The clinical data repeats the efficacy findings of onvansertib in bev naive patients seen in the company’s earlier Phase 1b/2 KRAS-mutated mCRC trial. In August 2023, Cardiff Oncology discontinued enrollment in the second-line ONSEMBLE trial to focus on its new lead program in first-line RAS-mutated mCRC. This decision was driven by the fact that both trials essentially test the same clinical hypothesis, the importance of deploying the company’s capital efficiently, and the FDA’s suggestion that Cardiff Oncology consider focusing on the first-line RAS-mutated mCRC setting given the lack of any new therapies approved in this large cancer indication in the last 20 years. At the time enrollment was discontinued, the ONSEMBLE trial had randomized 23 patients across three arms including a control arm of standard of care, or SoC, FOLFIRI+bev, an experimental arm with onvansertib added to SoC FOLFIRI+bev, and an experimental arm with onvansertib added to SoC FOLFIRI+bev. The trial included patients with mCRC who had a documented KRAS or NRAS mutation and had previously received one prior chemotherapy regimen with or without bev in the first-line metastatic setting. combination of onvansertib with SoC FOLFIRI/bev was shown to be well-tolerated and no major / unexpected toxicities were seen. Two Grade 4 TEAEs of neutropenia were seen in patients receiving 20 mg Onvansertib + SOC. Both patients recovered within 7 and 10 days after withholding the study treatment and no dose reductions in subsequent treatment cycles were needed. Both patients are still on trial.The patients’ median age was 53 years and 54% were male while 68% patients had previously received bev in their first-line treatment. Lastly, 12 of 21 evaluable patients remain on trial at the data cutoff date.