Newer cox-II inhibitors to face stringent scrutiny

Jayashree Padmini - New Delhi

The approvals of new cox-II inhibitors will have to go through stringent regulatory process in the future. Following the recent US FDA decision on valdecoxib and withdrawal of rofecoxib by innovator company Merck, the Indian regulatory authority is planning to have a closer scrutiny of data submitted by companies.

It may be recalled that in line with the international regulatory decisions, the Indian government has previously notified ban on rofecoxib and has now decided to withdraw valdecoxib from the market.

The notification to this effect will be issued shortly, informed the Drugs Controller General of India (DCGI).

In reply to a query about the long term strategy on newer cox-II inhibitors, the DCGI Ashwini Kumar said that the authority will closely examine the data for any new cox II inhibitors and their clones seeking marketing approval in the country. ‘‘We will have a closer analysis of the data and if required may seek more data from companies.’’ However, he said that the system in the country is still in an evolving stage and norms will be formulated from time to time accordingly.

Moreover, the cox-II inhibitor class of drugs are already under the regulatory scan in the Pharamcovigilance Programme which took off recently and in accordance with the data that will come from different centres the strategy on this class of drugs will be formulated, he said. Pharmacia’s Parecoxib, Pfizer’s Celebrex, Boehringer Ingelheim’s Mobic (meloxican) all are in the list of new cox-II inhibitors.

Pharma majors including Ranbaxy, Cadila Pharma, Zydus Cadila, Glenmark Pharma, Nicholas Piramal, Torrent, etc, have been cornering sizeable revenues from existing cox-II inhibitor drugs. However, with rofecoxib already out of market and valdecoxib falling in line, Ranbaxy has already voluntarily withdrawn its valdecoxib clone. It may be noted that the US FDA called for “black box” warning of increased cardiovascular and gastrointestinal risk labelling on all prescription versions of nonsteroidal anti-inflammatory drugs including Mobic, Naprosyn, Voltaren and more than 12 similar drugs.

The agency also wants to include warnings on over-the-counter painkillers such as Advil, ibuprofen, Aleve and naproxin. Acetaminophen and Aspirin are not affected by the warnings even though these can pose liver damage and stomach ulcers respectively. The new cox-2 inhibitors relieve arthritis pain with less risk of causing or irritating ulcers associated with the older anti-inflammatory drugs such as ibuprofen and Suilind.

Vioxx (rofecoxib) accounted for about $373 million in revenue in 1999. Celebrex generated about $1.5 billion in sales in its first year, making it the best selling first year prescription drug. Although, these new drugs cost about $750 per year more than generic anti-inflammatory drugs they have been deemed more appropriate for the elderly patients who have a higher risk of ulcers. However, citing the increased risk for a rare dangerous skin disease, as well as the increased risk for heart attacks and strokes, the US FDA went against the vote of its safety panel’s vote, and instructed Pfizer to remove its cox-2 inhibitor drug Bextra from the market.

— jayashreep@expressindia.com