Mylan and Watson win approval in USA for generics of B-MS' BuSpar

Mylan and Watson have been granted full approval by the US Food and DrugAdministration for their generic versions of Bristol-Myers Squibb's anxiolytic BuSpar (buspirone), apparently ending a legal wrangle which has been ongoing since last year (Marketletter December 11, 2000).

B-MS had listed a new patent in the FDA's Orange Book last November, a move which was immediately attacked by the generics firms as a ploy to try to block competition to BuSpar, which was the firm's fifth-largest product in 2000. Earlier this month, B-MS lost a lawsuit on the validity of this patent, clearing the way for generic competition (Marketletter March 19). While a temporary stay on this decision was ordered by the US Court of Appeals for the Federal Circuit, this was lifted on March 27 on the grounds that B-MS had not been able to demonstrate any likelihood of winning the case.

The availability of generic versions of the drug is expected to lead to a steep reduction in B-MS' BuSpar sales, which reached $709 million in 2000, an increase of 17% over the previous year.