HYDERABAD: Merck & Co’s decision to withdraw its patented drug Vioxx (rofecoxib) from the world market on the basis of severe adverse reaction, may have a spiralling effect on the entire Cox-2 class of compounds (relating to pain management) being brought out by the Indian pharma manufacturers. Not surprisingly, some analysts are apprehensive of the earnings of these pharma companies in the coming quarters.

While it was a forgone conclusion that Merck’s decision would pose a threat to about 40-odd desi brands that have rofecoxib as active pharma ingredient (API), speculation is now rife on the entire Cox-2 class of compounds that constitute almost 50% of the entire pharma market. Companies like Sun Pharma, Cipla, Cadilla Healthcare, and Dr Reddy’s Labs, are some of the prominent players in the Cox-2 segment.

On the refecoxib front (widely prescribed for tackling arthritis), Ranbaxy has announced on Thursday the withdrawal of its drug — Rofibax — which is the market leader with sales of about Rs 14 crore. Apart from Ranbaxy, Micro Labs and Juggat Pharma were the other two companies that have announced their decision to withdraw their drugs consisting of refecoxib as its bulk active.

Although the markets were buoyant on Thursday, with the BSE sensex gaining 36 points before closing at 5713, the sentiments in pharma sector were subdued. Cipla, whose turnover comprises a major chunk of refecoxib and Cox-2 class of compounds, opened at Rs 288 on NSE and closed lower at Rs 283 on Thursday. Sun Pharma and Dr Reddy’s, too, closed lower at Rs 424 and Rs 750 on the NSE.

Leading brands in refecoxib segment include, Cipla (Rofixx — Rs 3.75 crore), Sun Pharma (Rofact — Rs 3.5 crore), Unichem (Roff — Rs 13 crore), Dr Reddy’s (Mcrofy — Rs 4.26 crore), Torrent (Torrox — Rs 6.15 crore) and Lupin (Rofaday — Rs 5.35 crore).

Venkat Jasti, vice-chairman, Pharmexcil, however, said: “it is only the refecoxib drug that is posing a problem. It would be unwise to link the entire Cox-2 class of compounds to it. Moreover, the news has spread from Merck’s own submission that its product poses an increased risk of cardiovascular events, including heart attack and stroke, in patients on Vioxx. The side effects of the drug were also published in the US-based journal ‘Circulation’ in its April ’04 issue. There has been no mention about Cox-2 class of compounds”.