(Reuters) - Amgen Inc's trebananib drug for ovarian cancer extended the length of time that patients lived without the disease getting worse by about two months, meeting the main goal of a late-stage clinical trial, the company said on Wednesday.
The trial is the first of three pivotal-stage studies of the experimental drug, and analysts said U.S. regulators will likely need to see evidence that trebananib extends overall patient survival before considering the drug for marketing approval.
Amgen said median progression free survival (PFS) in the trial was 7.2 months for patients given trebananib and chemotherapy, compared with 5.4 months for patients treated with a placebo drug and chemotherapy.
"This is an incremental positive as expectations were very modest," RBC Capital Markets analyst Michael Yee said in a research note. "However, it remains uncertain, in our view, whether PFS benefit alone is sufficient for U.S. FDA (Food and Drug Administration) approval."
Shares of Amgen were down $1.05 at $96.88 in midday trading on Nasdaq.
Trebananib is designed to block the process used by tumors to grow the blood and lymphatic vessels they need to survive and spread.
Amgen said that while it was working on the primary analysis of overall survival for 2014, it saw a favorable survival trend in an interim analysis.
(Reporting by Caroline Humer and Deena Beasley; Editing by Jeffrey Benkoe and John Wallace)