The European Medicines Agency’s Committee for Human Medicinal Products has issued a positive opinion for US drug giant Pfizer and privately-held group Eyetech Pharmaceuticals’ eye therapy Macugen (pegaptanib sodium), recommending marketing clearance for the treatment of wet age-related macular degeneration.
Macugen is the first in a new class of ophthalmic drugs designed to specifically target vascular endothelial growth factor 165, a protein that acts as a signal in triggering the abnormal blood vessel growth and leakage that characterises neovascular AMD. It received its first marketing green light from the US Food and Drug Administration in December 2004 [[20/12/04f]], followed by Canada earlier this year, and Pfizer is expecting the European Commission to grant a marketing authorisation by year-end.
US approval was based on findings from two pivotal Phase II/III clinical trials with around 1,200 patients with all subtypes of neovascular AMD. Some 70% of patients receiving the 0.3mg dose of Macugen lost less than three lines of vision on an eye chart, compared with 55% of those receiving the control treatment. In addition, Macugen helped limit progression to legal blindness by 50% compared to controls.
Under the terms of the $745 million Pfizer/Eyetech partnership entered into in 2002 [[191202a ]], both groups co-promote the product in the USA, while Pfizer holds exclusive marketing rights in Europe. Macugen is expected to bring in net revenues of $175-$190 million dollars for Eyetech in the full-year to December 2005 [[23/06/05e]], according to the firm.
AMD is an age-related eye disease that ultimately destroys central vision. In the European Union, AMD is the leading cause of irreversible severe vision loss in patients over 50 years of age, and an estimated 500,000 people across the globe lose their vision each year from the disease, Pfizer notes.
Until Macugen’s introduction to the US market in January this year, the only FDA-approved treatment was limited to the predominantly classic subtype of neovascular AMD, which accounts for up to 25% of the neovascular AMD patient population, providing the agent with an immediate therapeutic advantage. Consequently, industry observers have forecast annual peak sales of around $1.0 billion for the agent.
However, Macugen could soon be facing strong competition from Novartis and Genentech’s potential blockbuster Lucentis (ranibizumab) if it makes it to market next year, as expected. According to Phase III data released earlier this year, Lucentis was shown to improve vision loss in wet AMD, whereas Macugen has, to date, only shown its efficacy in slowing vision loss from the condition [[19/07/05h]].