Cardiff reveals early data on challenger to Amgen's KRAS crown

Amgen has already won the KRAS race by getting Lumakras across the finish line, but Cardiff Oncology has just rolled out some early data for a follow-on candidate showing partial responses and extended survival without disease progression compared to standard of care.

Cardiff’s onvansertib is being trialed in a phase 1b/2 study in patients with metastatic colorectal cancer who have a mutation of the KRAS gene, according to a Wednesday release. The therapy is being combined with chemotherapy and Roche's stalwart Avastin. Patients must have failed on chemotherapy and or/Avastin prior to entry in the trial.

The therapy achieved an initial partial response in eight of 19 patients, or 42%, who had received the middle dose and were evaluable as of the cut-off date. The response was confirmed in seven of those patients, or 37%, after further follow-up. This compares to an objective response rate of 5% to 13% seen in historical controls of patients who received standard of care.

For all dose levels, 12 patients out of 32, or 38%, achieved a partial response and 10 out of 32, or 31%, had a confirmed response.

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The trial has not yet reached a median progression-free survival, but evaluable patients have reached 9.4 months, compared to a historical length of 4.5 to 5.7 months.

Onvansertib was well tolerated, however 10% of adverse events were reported as a grade 3 or 4, meaning they required medical intervention or hospitalization. Cardiff said the events were manageable and reversible with supportive care.

Cardiff’s shares bounced on the KRAS news, rising around 20% to $8.44.

The California biotech has some stiff competition in the KRAS game. Amgen, of course, is well ahead of the pack after receiving an FDA nod for Lumakras in May for non-small cell lung cancer (NSCLC). The Big Pharma has big plans for the KRAS inhibitor, including in advanced colorectal cancer.

RELATED: Amgen's KRAS rival Mirati gets a shot in the arm with breakthrough tag for follow-on therapy

Another company on Amgen’s heels is Mirati, which has had an up-and-down journey getting a KRAS rival towards an FDA submission. But the biotech got a boost in June when the agency handed over a breakthrough therapy tag for adagrasib in patients with NSCLC who have a G12C mutation.

Cardiff is also testing onvansertib combinations in phase 2 studies of patients with second-line metastatic pancreatic ductal adenocarcinoma and metastatic castrate-resistant prostate cancer.