While the court upheld a lower court decision that Ranbaxy's proposed generic drug infringed the basic Australian patent (number 601981) on atorvastatin (Lipitor), it invalidated the second patent covering the calcium salt of atorvastatin. The basic patent is valid till May 2012 and the salt version patent expires by September 2012, sources said. Both Pfizer and Ranbaxy can appeal against the decisions.
Lipitor is the largest selling drug in the world, with global sales of over $13 billion.
The Australian Federal court in Victoria had ruled one of Pfizer's patents as invalid for in-utility, false suggestion and misrepresentation in obtaining Australian patent 628198 (the salt patent), Ranbaxy said in a statement.
"We are pleased with this decision as it advances the entry of Ranbaxy's generic atorvastatin in Australia to May 18, 2012," said Jay Deshmukh, Ranbaxy's senior vice president - global intellectual property.
Ranbaxy intends to appeal against the decision on the basic patent.
A few weeks ago, the Federal Court of Canada had reversed a lower court order and prohibited the launch of Ranbaxy's generic Lipitor in Canada before the expiry of calcium salt patent in Canada in November 2011. In the first week of March, a Netherlands court had also given a verdict preventing Ranbaxy from launching its generic version before the expiry of Pfizer's patent.
However, Ranbaxy has been a major winner in the US patent battle on Lipitor, and as the case stands, it may be able to market the generic version from March 2010. The sales of Lipitor in the US are over $7 billion and any marketing exclusivity on patent expiry could help Ranbaxy to reap an upside of over $250 million in six months, according to analysts.
The US generic laws specify that the first successful challenger of an innovator's patent in the country gets a marketing exclusivity of six months.
