Takeda's norovirus vaccine misses endpoint in early-phase trial
When Takeda bought LigoCyte Pharmaceuticals last year, it hitched the near-term fate of its nascent vaccine unit to a jab for the vomiting and diarrhea bug, norovirus. This week, exactly one year after moving to buy LigoCyte, Takeda revealed the vaccine missed its primary endpoint in an early-phase trial.
Takeda hoped to show the vaccine cut incidence of acute gastroenteritis of any severity and laboratory ascertainment for norovirus. While fewer people in the vaccine group had symptoms of gastroenteritis than those receiving a placebo, the difference between the treatment arms was insufficient for Takeda to meet its primary composite endpoint. In an abstract presented at IDWeek 2013, researchers suggested the failure may stem from illness definitions and assays lacking the ability to differentiate infection or disease.
Nonetheless, Takeda's vaccine chief Dr. Rajeev Venkayya said he was "very encouraged" by the results. While the trial missed its primary goal, a 52% drop in vomiting or diarrhea of any severity among the vaccine group meant it met its secondary endpoint. The effect of the vaccine was measured by giving volunteers two doses and then infecting them with norovirus. Having established the vaccine is safe and has some effect on norovirus symptoms, Takeda is now planning future field trials. The optimization of confirmatory laboratory testing is high on the company's agenda ahead of its next study.
Analysts have previously tipped the vaccine to generate sales of $400 million a year, giving Takeda a solid start in the sector. The final figure will depend on the success of subsequent trials and how narrowly it is used, if approved. "It could be used for specific populations or situations--in those at a higher risk of severe disease such as the elderly or at high risk for infection or transmission such as in day care, people going on a cruise, those in nursing homes or in the military," lead study author Dr. David Bernstein said.