Two breast cancer treatment advocacy groups have written to FDA asking that the agency refrain from changing the approved labeling for Genentech’s Avastin. The letter from Komen for the Cure and Ovarian Cancer National Alliance is in response to an FDA advisory panel recommendation that the agency revoke an accelerated approval indication for Avastin for combination use with paclitaxel for treating previously untreated advanced HER2-negative breast cancer.

The panel voted 12 to 1 in favor of removing the indication from Avastin’s approved uses, with panel members agreeing that two post-approval studies did not show the therapy’s effect to be clinically significant. They acted after considering an FDA staff briefing that said the “risk-benefit ratio when added to the standard chemotherapeutic regimens…may not be considered favorable.”

“We recognize the benefits of Avastin overall are modest for women with metastatic breast cancer,” said ambassador Nancy G. Brinker, Komen’s founder and CEO, in the letter to FDA. “However, we do know that for some women, Avastin offers a greater than modest benefit. We hope that this decision will not restrict access to Avastin to all patients.”

The letter argued that many doctors report patients taking Avastin enjoy “better than modest results,” and that the decision to use Avastin should be made between a woman and her doctor.