Astellas Pharma this morning said it has begun legal proceedings against several Spanish generics companies for infringing its patent for Omnic (tamsulosin hydrochloride), which is also available in the country under the brand name Urolosin, manufactured by partner Boehringer Ingelheim.

The companies involved in the lawsuit are Ratiopharm Espana, Laboratorio Stada, Laboratorios Edigen, Merck Genericos, Bexal Famaceutica, Sandoz Farmacéutica and Teva Genericos Espana – all of which have launched already or are planning to launch a modified-release capsule containing tamsulosin hydrochloride onto the Spanish market.

Astellas claims all the product offerings have “the same relevant characteristics” as the original capsules, triggering the action in a Madrid court.

The patent covering Omnic, a product to treat benign prostatic hyperplasia, a precursor condition to prostate cancer, is not due to expire until August 24 next year and Astellas said it had previously sought confirmation from Spanish generics firms that they would not launch until this date. The above listed did not respond and have, with the exception of Teva, already pushed their offerings onto the Spanish market.

Astellas will also seek an injunction to prevent copycat Omnic from being sold until this date, with this strategy having already proved successful in Germany. In February it managed to put a stop to the early commercialisation of tamsulosin by several firms there, including Hexal, Sandoz, Merck, Ratiopharm and Synthon, and Astellas believes the Spanish court “will come to the same positive result.”

The patent invoked in the Spanish proceedings is a parallel patent to the European patent on which the court injunctions have been based in Germany, and the generic capsules marketed in Spain are the same capsules as those marketed in Germany.