WASHINGTON (AP) -- Federal health scientists said Friday that follow-up studies of a Roche breast cancer drug show it failed to slow tumor growth or extend patient lives, opening the door for a potential withdrawal in that indication.
The Food and Drug Administration approved Roche's blockbuster Avastin in 2008 based on early-stage trials showing it shrank tumors caused by breast cancer. The decision was controversial because drugs for cancer patients who have never been treated before must usually show evidence they extend lives.
Avastin's so-called "accelerated approval" was based on the condition that later studies would show a survival benefit.
But in briefing documents posted online, FDA reviewers said two follow-up studies recently submitted by Roche failed to show that Avastin significantly extended lives compared to chemotherapy alone.
Additionally, the FDA said more recent data did not confirm the tumor shrinkage seen in earlier studies.
Patients taking Avastin showed significantly more side effects, including high blood pressure, fatigue and abnormal white blood cell levels.