The Indian pharmaceutical companies are involved in patent litigations of a mere 40 drugs, out of the 135 known patent litigation drugs in the US.
This is despite the claims by major Indian players such as Ranbaxy and Dr Reddy's at having secured over 20 first to file status abbreviated new drug applications with the US Food and Drug Administration.
The FTF entitles the patent challenger a six-month exclusive selling of generics on the patent expiry of innovator companies under the US law.
The FTF status for 55 drugs is known and the scorecard is three for Ranbaxy and one each for Dr Reddy's, Glenmark, Sun and its US subsidiary, Caraco.
Against this, the leading global generic majors such as Israel's Teva Pharmaceuticals has 16 FTFs, US-based Barr Pharmaceuticals (7) and Mylan (5).
"Most of the Indian companies do not prefer the expensive patent litigation route and rely on the non-infringement route. That is one reason why Indian companies account for less than one-third of all the patent litigations in the US," said Gopakumar G Nair, managing director, Patent Gurukul.
Drugs worth $65-70 billion are expected to go off-patent in the next 4-5 years, according to a KPMG estimate.
According to an IMS Health data, drugs worth $20 billion in annual sales will face patent expiry in 2008 and big selling products such as Risperdal, Fosamax, Topomax, Lamictal and Depakote are expected to lose market exclusivity in major markets around the world next year.
Out-of-court settlements with innovator companies are common these days and in many cases, innovator companies prefer not to disclose the details, Gopakumar added.
"Ranbaxy publicised about ten litigations and is said to have about 22 FTFs. This means that it is involved in more litigations. Innovator companies are also inclined to go for out-of-court settlements and align with the generic challengers to protect the sales of their drugs, going off patent. Therefore, the complete picture on litigation is evolving," said Sarabjit Kaur Nangra, senior sector analyst, Angel Broking.
However, sources noted that the Indian companies are unlikely to grab a good share four blockbuster drugs going off-patent in 2008.
They said the six-month exclusivity for Merck's osteoporosis drug called Fosamax (alendronate sodium) is for Teva and the Indian companies are not involved in patent fight for this drug which boasts of $1.48 billion sales in the US market.
Besides, Mylan has already secured exclusive 180 day sales for Ortho McNeil's (J&J group company), Topamax (Topiramate), a $1.4 billion drug in the US. The other contenders for this drug are Barr and Cobalt.
GSK's Lamictal (Lamotrigine) is comparatively small with $ 900 million in the US and the generic challengers to this drug are not known.
Wockhardt, along with Teva and Impax, is among the contenders for Abbott's Depakote ER (Divalproex Sodium), a $430 million (US sales) drug for epileptic seizures. Though the FTF status is not known, Dr Reddy's and Mylan are believed to be the main contenters for Risperdal, the schizophrenia drug of Johnson and Johnson group company, Janssen, with $2 billion sales in the US.
Sources also added that the Indian generic majors are not in the picture for some of the real blockbuster drugs which are going off-patent, progressively until 2020.
Teva is known to be the only challenger so far for Merck-Schering Plough's Singulair (Montelukast sodium), a $2.6 billion asthma drug in the US. In the case of BMS-Sanofi Aventis's Plavix (clopodrogel bisulphate), a $5.8 billion stroke prevention drug in the US, the Canadian company Apotex has FTF and the major fight on patent expiry and exclusivity period will be between Teva and Cobalt Pharmaceuticals.
Similarly, in the case of Takeda's Prevacid, a $3.3 billion drug in the US, Teva is the lone challenger. When Eli Lilly's best selling schizophrenia drug Zyprexa, accounting for $4.4 billion in US sales, goes off patent in 2011, Ivax will have the exclusive six-month sales rights for most of the six dosage forms of the drug. Dr Reddy's is believed to have first-in-line status for the 20 mg dose of Zyprexa.