Study raises questions over benefit of Roche's Gazyva cancer drug
December 05, 2016 at 08:39 AM EST
ZURICH, Dec 5 (Reuters) - Roche's Gazyva cancer drug did not show a significant overall survival benefit and raised greater safety concerns than its predecessor Rituxan, a study showed, raising doubts over the Swiss pharmaceuticals group's bid to replace a key blockbuster.