Onvansertib cut the risk of death or disease progression by 62% versus standard of care, but analysts await more detailed data.
Tuesday was difficult for Cardiff Oncology, which lost two high-level officials and posted middling Phase II data for its PLK1 blocker onvansertib that raises more questions than answers.
The California-based company closed the day at $2, a nearly 32% drop from its ending price of $2.95 on Monday.
“[Tuesday’s] update slants in a negative direction,” analysts at William Blair told investors in a note written after the data release. “With $60 million cash at the end of the third quarter, the company will likely seek dilutive funding or partnership opportunities to fund the pivotal study for onvansertib.”
In the Phase II CRDF-004 study of metastatic colorectal cancer (mCRC), Cardiff tested 20-mg and 30-mg doses of onvansertib with two standard-of-care regimens: FOLFIRI plus bevacizumab and FOLFOX plus bevacizumab. FOLFIRI and FOLFOX are both chemotherapy combos, while bevacizumab is a monoclonal antibody.
Results presented on Tuesday showed that patients on FOLFIRI plus bevacizumab had a confirmed objective response rate (ORR) of 42.1%, and that adding 20-mg onvansertib to this improved the outcomes slightly to 44.4%. The impact of 30-mg onvansertib was more pronounced, spiking ORR to 72.2%, though this failed to reach statistical significance.
This higher-dose onvansertib also resulted in stronger progression-free survival, cutting the risk of death and disease progression by 62% versus FOLFIRI plus bevacizumab. William Blair analysts conceded that they are “intrigued” by this data point, though “we emphasize the wide confidence interval of 0.12-1.17, likely attributable to the small sample size.”
Cardiff did not present comparison data for FOLFOX plus bevacizumab, though the biotech admitted in its news release that adding onvansertib to FOLFIRI plus bevacizumab “performed better” than the FOLFOX-based regimen. Based on these findings from CRDF-004, Cardiff has decided to move forward only with the 30-mg onvansertib dose added to FOLFIRI plus bevacizumab, for which a registrational study in frontline RAS-mutated mCRC is set to start later this year.
“We look forward to the detailed data release, along with longer follow-up and a biologically plausible explanation of the differences in efficacy outcome between FOLFOX- and FOLFIRI-based combination regimen,” William Blair said on Tuesday.
Also on Tuesday, Cardiff announced that its CEO Mark Erlander and CFO James Levine were leaving the organization. Mani Mohindru, member of the company’s board of directors since 2021, will become interim CEO, while Brigitte Lindsay, who was previously senior vice president of finance, has been promoted to chief accounting officer.
Cardiff is in the process of searching for permanent replacements for Erlander and Levine.
