P.T. Jyothi Datta
New Delhi/ Mumbai, Oct. 17
PFIZER may have won a favourable ruling from the UK court in its battle against the domestic pharma major, Ranbaxy Laboratories, over its patent for the anti-cholesterol drug, `Lipitor'. But officials of Ranbaxy and Dr Reddy's Laboratories (DRL), which lost a patent case in the US some time ago, maintain that the losses incurred have not deterred them from pursuing litigations in order to make the most of the 180-day market exclusivity in the case of a win. So, even if Pfizer has been able to get the upper hand in the UK litigation and Novartis having gained on its anti-fungal drug Lamisil, Ranbaxy and DRL too have scored with their successful challenge of GlaxoSmithKline (GSK)'s and Eli Lilly's patent of `Ceftin' and `Prozac' respectively.
Moreover, there are several cases still waiting for a decision. Ranbaxy for instance, besides pursuing its appeal against Pfizer for Lipitor, has been sued by GSK for drug Valtrex used for herpes medication, the patent for which expires in February 2007.
When a company like Ranbaxy takes on a deep-pocketed company such as Pfizer, it would have done its homework, says an analyst. But, it is a big risk, big reward and big fall game, a strategy that few companies are following now, he adds.
The patent challenge pipeline of Dr Reddy is equally long. It comprises Eli Lilly's schizophrenia medication Zyprexa, Esai Inc's ulcer drug Aciphex, Pfizer's anti-depressant Zoloft and antipsychotic medicine Risperdal from Johnson and Johnson.
Added to this is the trend of challenging patents that are being de-listed. This is a strategy followed by innovator companies, mostly multinationals, to prevent the first-to-file company from getting the 180-day exclusivity period.
Innovator companies, on their part, are adopting delaying tactics to take the wind out of the challenge from drug companies making generic or copycat drugs. Some innovators delist their patent, thus voluntarily bringing the drug out of exclusivity. This strategy kills the "first-to-file" advantage that generic drug-makers try to wangle for themselves as the patent on a drug comes close to expiry.
Merck, for instance, had withdrawn patents for its cholesterol-lowering drug Zocor (simvastatin), which has been challenged by Ranbaxy and Ivax Pharmaceuticals. Similarly, it is learnt that Pfizer has withdrawn some patents for drug Detrol, used to treat overactive bladder, and GSK has done ditto for its migraine-relieving medication Imitrex. Allowing `authorised generics' is another strategy adopted by innovator companies, where they permit a generic competitor to make a copycat version. This again brings down the price on an exclusive drug, thus making it unattractive for other generic players.
Though the final outcome on the dispute over Lipitor may set a benchmark of sorts, the death-knell has been sounded for `Para IV' type patent challenges in the long haul, says Ms Krishna Sarma, a consultant on intellectual property rights (IPR) issues.
Even as they are gearing for legal battle in the days ahead, generic companies are also looking at non-infringing process patents so that they do not tread on the toes of innovator companies or the original maker of a drug, observes another analyst.
According to analysts, drugs worth $60 billion are expected to go off patent in the next few years and innovator companies are likely to defend patent challenges aggressively.
"With very few new molecules in the research and development (R&D) pipeline and several set to go off-patent in the next five-six years, innovators will strategise to protect their turfs. Litigation costs are also expected to go up substantially," said the head of a multinational company.