Results from a phase 3 study demonstrate Macugen (pegaptanib sodium) significantly improved vision in patients with diabetic macular edema (DME), a complication of diabetes that is a leading cause of blindness in people of working age. In the study, 37 percent of patients treated with Macugen gained two lines, or 10 letters, of vision on the ETDRS eye chart at 54 weeks, compared to 20 percent of patients who received a sham (placebo-like) procedure which consists of anaesthesia and a simulated injection in the eye (p=0.0047).

The data were presented today at the World Ophthalmology Congress in Berlin by Frank G. Holz, an investigator in the trial and director of the University Eye Hospital at the University of Bonn
in Germany.

“These encouraging Phase 3 results demonstrate that Macugen has the potential to improve vision in people with DME, a serious complication of chronic diabetes,” said Marla B Sultan, global clinical lead for Macugen at Pfizer. ”Currently there are no approved pharmaceutical treatments for DME, and when left untreated, about one out of four people with this condition will develop moderate vision loss within three years,” said Dr Sultan. “Pfizer is pleased to be exploring Macugen as a potential treatment option to address this unmet medical need.”

The phase-3 trial met its primary endpoint of the proportion of patients gaining greater than ten letters vs sham at one year. On average, patients treated with Macugen gained 5.2 letters of vision at year one compared to 1.2 letters for patients receiving sham (p <0.05). At the end of year two, patients receiving Macugen had gained on average 6.1 letters of vision compared to 1.3 letters for patients in the sham arm of the study (p <0.01).

All patients enrolled in the study were eligible to receive laser therapy, the current standard of care for DME, beginning at week 18 of the study at the physician’s discretion using ETDRS guidelines. Dr Paul Mitchell, an investigator in the trial and director of the Centre for Vision Research at the Westmead Millennium Institute for Medical Research in Westmead, Australia, said,

“There is a clear need for new treatment strategies for DME. The Macugen phase-3 study in DME, along with other recently published studies, including those new data presented this week in Berlin, sheds light on the potential role of VEGF-inhibition in the management of this sight-threatening disease.”

Pfizer plans to submit to the European Medicines Agency a variation to the European Marketing Authorization for Macugen to include an indication for DME.

Macugen, a selective inhibitor of VEGF-165, is indicated in Europe and the United States for the treatment of neovascular age-related macular degeneration (wet AMD) and is administered in a 0.3-mg dose once every six weeks by intravitreal injection.