Indian drugmaker Dr Reddy's Laboratories says that net income for the fourth quarter ended March 31 sank 68.3% to 1.03 billion rupees (around $24 million) as its generics products in the USA faced increased competition.

Sales fell 15% to 13.3 billion rupees and were down to 2.5 billion rupees from 5.6 billion rupees in North America. However the figures from a year earlier were boosted by one-time gains from a 180-day exclusivity period for its generic version of GlaxoSmithKline's anti-nausea drug Zofran (ondansetron). Generic Zofran made up 16% of Dr Reddy's revenues in the same quarter a year ago.

Despite the declines at the firm’s North America generics business, fourth-quarter revenues from Dr Reddy’s branded formulations unit rose 22% to 3.5 billion rupees, driven by growth in India, Romania and the CIS states. Revenues from Betapharm, the German company it acquired a year ago, rose to 2.4 billion rupees, a solid performance given the pricing pressures and competition in that country.

For the full fiscal year, net income more than halved to 4.68 billion rupees, while sales were down 23% to 50 billion rupees.