Phase Ib/II trial of PCM 075 shows efficacy in metastatic KRAS colorectal cancer.- Cardiff Oncology

Cardiff Oncology announced an electronic poster presentation of clinical data further demonstrating the safety, efficacy and durability of response of PCM 075 (onvansertib) in KRAS-mutated metastatic colorectal cancer (mCRC) patients. It shows that 10 of 11 (91%) patients achieved disease control (SD – stable disease plus PR – partial response) with only 1 patient progressing in <6 months while on treatment. additionally 5 (45%) patients achieved a partial response (pr); 4 patients had a confirmed pr with 1 patient going on to curative surgery; 1 patient with an initial pr went off study prior to confirmatory scan due to non-treatment related event. and 8 of 11 (73%) patients demonstrated durable response ranging from 6 to>12 months, and 4 patients remain on treatment. In a biomarker analyses, all 5 PRs were associated with different KRAS mutation variants, including the 3 most common that comprise nearly 80% of mutations in CRC. Patients achieving a PR showed the greatest decreases in plasma KRAS mutation levels (ranging from -78% to -100%) after one cycle of therapy. In terms of safety, the first two onvansertib dose levels (12 and 15 mg/m2) have been cleared for safety; four patients have been treated at the third dose level (18 mg/m2) and two more will be enrolled. Onvansertib in combination with FOLFIRI/bevacizumab is safe and well tolerated with only 9% of AEs being grade 3 or 4; none being attributed to onvansertib and all being resolved within 2.5 weeks. No major or unexpected toxicities have been attributed to onvansertib. Data were presented at the European Society of Medical Oncology (ESMO) Virtual Congress 2020.