US firm, Abbott laboratories, has proved Indian drug firm Glenmark, at fault. Glenmark has lost a patent case over hypertension drug, Tarka in the US court.

US Jury of five members in Newark, New Jersey has directed Glenmark to stop selling a copy of Abbott Laboratories hypertension drug 'Tarka'. The jury has rejected the validity of the patent that expires in February 2015. The Jury has also directed Glenmark to pay a compensation of about $16 million in damages to the US firm. Glenmark will appeal against the verdict because they argued that the patent covered an invention that was protected by an expired patent.

Glenmark was selling the generic version of 'Tarka', whose original license was held by French drug maker Sanofi-Aventis and was later sold to Abbott. Abbott claims that they have paid $290 million for the exclusive license to Tarka.

Due to this defeat Glenmark shares closed 6.46% down on the BSE.

Glenmark is seeking the approval from The US Food and Drug Administration for the sale of generic version of Tarka in May. Subsequently Glenmark has launched the generic version of Tarka in June last year after the US District Court refused to issue an injunction against its launch.

With this, Glenmark became the first firm to challenge the sales of Tarka in US market. Tarka has annual sales of about $60 million in the US market and Glenmark has the perfect opportunity to earn revenues in the US market.

Sources revealed that Abbott is asking for $25 million in damages from Glenmark for introducing the drug 'at risk'.

The Judge's final decision is yet to come in another six weeks which may be different from that of the jury. If Glenmark loses this patent case, it is expected that it has to pay much more to the patent holders of the drug. But if everything went in its favor then it will become the sole ANDA filler on this drug, might be able to re-launch generic Tarka immediately.