Cardiff's waning dataset is still good enough

Cardiff Oncology, the biotech formerly known as Trovagene, is making a bold claim to being able to hit Kras-mutant colorectal cancer with its PLK1 inhibitor onvansertib. However, dribbling out data every few months from its uncontrolled trial has resulted in stock price volatility. Yesterday’s update elicited a 15% rise at today’s open, after shares fell 31% at the time of an Asco-GI presentation. Moreover, it is hard not to see the efficacy as waning, with confirmed remission rates dipping from 36% to yesterday’s 31%. Still, this is perhaps to be expected as more patients yield data, and with Cardiff worth under $300m many investors see an opportunity. The group yesterday boldly pointed to Mirati and Amgen’s Kras inhibitors, adagrasib and Lumakras, which in colorectal cancer have respectively yielded ORRs of just 17% and 7%. Indeed, Amgen has given up on colorectal cancer in favour of NSCLC; an adagrasib colorectal cancer late-breaker at Esmo is keenly awaited. While caveats remain for Cardiff, including that its trial combines onvansertib with chemo and Avastin, perhaps the biggest question is how much work is needed to yield an approvable dataset – a major concern for a small biotech with limited cash.