Ranbaxy Laboratories has managed to capture close to 2.5 per cent of the generic Lipitor's market share in the US within the first few days of the launch.

According to a JP Morgan report, Watson Pharmaceuticals and Ranbaxy, the two generic drug makers collectively captured 14.6 per cent of US prescription volume of the cholesterol-lowering drug. But the majority of this has gone to Watson Pharma, which launched the drug just two days ahead of Ranbaxy.

The JP Morgan report, citing data from prescription drug tracker IMS Health, said that about 97.6 per cent of the total generic versions sold in the market were from Watson in the first few days, with Ranbaxy holding the remainder. While Watson Pharma had announced its launch on November 30, the Indian drugmaker had started selling on December 1.

Chemically known as Atorvastatin, Lipitor is the world's best selling drug with annual sales of over $10 billion in the US. Analysts expect Ranbaxy to earn as much as $600 million during the six-month exclusivity period, where no other drugmakers other than the two are allowed to market the drug along with Pfizer.

According to the JP Morgan report, more than 9.38 lakh prescriptions for drugs containing Lipitor's active ingredient, Atorvastatin, were prescribed for the week ended December 2. About 8 lakh or 85.4 per cent were written for the branded Lipitor.

Analysts in India said that though it is still early days to determine the success of Ranbaxy's launch, a 2.5 per cent market share in the first few days was not a bad start. This comes even as Pfizer is aggressively trying to protect its market share through unprecedented marketing strategies, including discounts to consumers and health plans during the crucial six months.

tkt@thehindu.co.in