An Indian court on Monday rejected a challenge to the country’s patent laws by Swiss pharmaceutical giant Novartis, a decision hailed by medical aid groups as a victory for millions of poor patients in developing countries.

Novartis said the court ruling — over the definition of a new or improved drug — was a blow to the idea of intellectual property rights and would have long-term negative effects on research into new drugs. However, the company said it was unlikely to appeal the ruling.