The European Commission has approved Pfizer’s Macugen product for the treatment of neovascular age-related macular degeneration, an eye disease that destroys central vision.

Macugen (pegaptanib sodium injection) has been proven to prevent and reduce vision loss in patients with neovascular AMD, and becomes the first treatment to be approved in Europe for the treatment of all types of neovascular AMD. Pfizer licenses commercialisation rights to Macugen in Europe from OSI Pharmaceuticals.

In addition to the USA and EU, Macugen has also been approved by regulatory authorities in the Canada, Brazil, Argentina, Peru, Pakistan and the Philippines, with filings submitted in 15 other countries, including Australia, Switzerland and Mexico.

At present, the market for AMD therapies is valued at around $600 million, with Novartis/QLT’s photodynamic therapy Visudyne (verteporfin) dominating the sector with sales of around $450 million last year.

Macugen has been growing fast, with 50,000 patients already treated with the drug in the USA since it was approved there in December 2004. But questions are already being raised about the prospects for the drug in the face of upcoming competition from a drug which work in a similar fashion, Novartis and Genentech’s Lucentis (ranibuzumab), which was filed for approval in the USA in December 2005.

Novartis and Genentech claim that their product is the only one to have shown an improvement in visual acuity in clinical trials.

Meanwhile, there are a series of other drugs for wet AMD coming through trials, and off-label use of Genentech's cancer drug Avastin (bevacizumab) could also raise competition in the marketplace.

Other companies developing treatments for AMD include: eye care specialist Alcon, which is gearing up to file for approval of its Retaane (anecortave acetate) candidate; Miravant Pharmaceuticals, which has a photodynamic therapy - Photrex (rostaporfin; SnET2) - in Phase III trials; Acuity Pharmaceuticals which has a VEGF inhibitor based on the emerging small interfering RNA (siRNA) technology in Phase II; and Genaera, with Evizon (squalamine lactate) in Phase II.

Neovascular AMD is the leading cause of irreversible severe vision loss in patients older than 50 years of age in the western world, affecting about 500,000 people worldwide each year. There are approximately 2.5 million people in the EU living with some form of neovascular AMD, according to Pfizer.