A recent international study has brought a new anticancer drug that targets a mutation in a gene called
KRAS closer to clinical application.
The findings reveal few serious side effects in individuals affected by cancer and were published in the
New England Journal of Medicine.
The study involved 35 institutions across 12 countries, with
Dr. Adrian Sacher, clinician investigator at Princess Margaret Cancer Centre, the lead author.
KRAS plays a role in helping cells to grow and divide, and when its function is altered it can drive normal cells to become cancerous.
KRAS is one of the most common genes that are mutated in solid cancers, but until recently treatments were not available that could directly target this gene pathway.
Genentech, the sponsor of the study, developed the drug divarasib to target a specific type of
KRAS mutation found in 12 per cent to 14 per cent of patients with non-small-cell lung cancer, and 4 per cent of patients with colorectal cancer.
This new agent may provide a more effective, targeted therapy for patients with this particular change in their
KRAS gene, and early indications are that it may be more effective than the other, early attempts to target
KRAS.
'The best response rate for a
KRAS inhibitor to date'
This early phase study tested the safety of divarasib in patients with cancer, and found few serious side effects, with only 3 per cent of patients stopping the medication because of adverse side effects.
The response of patients' cancers to divarasib was impressive, with over half of patients with metastatic non-small-cell lung cancer and nearly one-third of those with colon cancer showing a response to treatment.
"This study demonstrates impressive clinical activity and tolerability for divarasib in tumors with
KRAS G12C mutations," explains Dr. Sacher. "We are conducting randomized studies of divarasib to confirm these results and are also evaluating divarasib as a combination therapy with other novel drugs.
"But that said, divarasib has demonstrated the best response rate for a
KRAS inhibitor to date and the team is excited by these results.
"We are hopeful that this study constitutes the first step in developing new treatment strategies based around selective KRAS inhibitors that lead to new treatment options for our patients with lung, colon and other solid tumors," says Dr. Sacher.
This work was supported by Genentech, Fundació La Caixa, the UK National Institute of Health Research and The Princess Margaret Cancer Foundation. The study was sponsored and designed by Genentech.
Read more about the study.
