Generics manufacturer, Alpharma, has lost out in its bid to retain the 180-day period of marketing exclusivity for a copycat version of Pfizer’s blockbuster epilepsy drug, Neurontin (gabapentin) [[04/02/05g]], after it settled litigation on Friday by agreeing to allow Ivax to sell a rival version of the product before the exclusivity expires.

Ivax filed an appeal with a US appeals court late last year, seeking to reverse an earlier court decision upholding Alpharma’s right to exclusivity. Alpharma has agreed to allow Ivax to start marketing its capsule version of the drug on March 23, 2005, while its tablets will hit the market on April 29 – the exclusivity periods had been due to end on April 6 and June 11 respectively. In return, Ivax has agreed to drop the lawsuit.

Alpharma’s share price dipped slightly during trading on the Nasdaq on Friday, after it revealed that the agreement would likely reduce sales of its version of the product during the exclusivity period.