US drug giant Pfizer has settled another lawsuit over its Lipitor (atorvastatin) patents – this time with Canadian company Apotex.

The move comes just two months after Pfizer made a deal with generics maker Ranbaxy.

The Apotex lawsuit evolved after the company was intent on launching a generic version of Lipitor prior to the patent expiring in 2010.

According to Pfizer’s quarterly report, Apotex and Pfizer entered into an agreement in July to settle the litigation, “subject to certain conditions”. The conditions and terms of the agreement have not been disclosed.

Apotex was unavailable for comment yesterday.

Lipitor’s competition
Since Lipitor was launched, the cholesterol lowering drug has gained much fame and has become the best selling drug in its class. As a result, the competition and pressure from generics manufacturers has been strong, leading to several patent disputes as other companies look at grabbing a piece of the Lipitor-financial-success-pie.

On June 18, Pfizer and Ranbaxy entered into an agreement over Lipitor, which would see Ranbaxy obtaining a license to sell a generic version of Lipitor in the US from November 30, 2011.

The companies had been dueling over the validity of the Lipitor patents, with Ranbaxy hoping to launch a generic version as early as March 2010, just as Lipitor’s basic patent was set to expire.

The deal now spells the end of virtually all worldwide patent litigation involving the blockbuster drug. The deal also means Pfizer will get an extra 20 months of revenues before Ranbaxy’s generic hits the market. Meanwhile, Ranbaxy will have a 180-day period of exclusivity from the November date in 2011 before other generic manufactures launch their versions.

The agreement does not cover patent disputes in Finland, Spain, Portugal, Denmark and Romania.

In Pfizer’s second quarter results, Lipitor increased 9% to $2.98 billion.