Solvay discontinues CB1 obesity drug SLV319

Belgian drugmaker Solvay Pharmaceuticals has discontinued all R&D activities for SLV319, a selective cannabinoid type 1 antagonist, that was in Phase II testing for obesity. Results recently confirmed its clinical activity and efficacy but Solvay was considering its development in the current regulatory framework after the return of rights to the drug in September. A once-promising class of obesity drugs, the CB1 blockers were dealt a decisive blow when Pfizer and Sanofi-Aventis decided to discontinue their individual CB1 products earlier this month, citing the tough regulatory environment prompted by findings that Sanofi's first-in-class Acomplia (rimonabant) increased the risk of suicide (Marketletter November 10).