In this double-masked Phase II trial, patients were initially treated with either fixed monthly or quarterly dosing for 12 weeks and then continued to receive treatment for another 40 weeks on a physicians’ research network (PRN) dosing schedule.
Patients receiving monthly doses of VEGF Trap-Eye of either two or 0.5mg for 12 weeks followed by PRN dosing achieved mean improvements in visual acuity versus baseline of nine letters (p<0.0001 versus baseline) and 5.4 letters (p<0.085 versus baseline), respectively, at the end of one year. The proportion of patients with vision of 20/40 or better increased from 23% at baseline to 45% at week 52 in patients initially treated with 2mg monthly and from 16% at baseline to 47% at week 52 in patients initially treated with 0.5mg monthly. During the week 12 to week 52 PRN dosing period, patients initially dosed on a 2mg monthly schedule received, on average, only 1.6 additional injections and those initially dosed on a 0.5mg monthly schedule received, on average, 2.5 injections. Patients receiving monthly doses of VEGF Trap-Eye of either two or 0.5mg for 12 weeks followed by PRN dosing also achieved mean decreases in retinal thickness versus baseline of 143 microns (p<0.0001 versus baseline) and 125 microns (p<0.0001 versus baseline) at week 52, respectively. While PRN dosing following a fixed quarterly dosing regimen also yielded improvements in visual acuity and retinal thickness versus baseline at week 52, the results generally were not as robust as those obtained with initial fixed monthly dosing. VEGF Trap-Eye was generally well tolerated and there were no drug-related serious adverse events. George Yancopoulos, president of research laboratories at Regeneron, said: "These study results confirm the rationale for our Phase III clinical program for VEGF Trap-Eye in wet age-related macular degeneration (AMD). These trials are designed to optimize improvement in visual acuity with fixed-dosing regimens of either every four weeks or every eight weeks for one year and then study how these vision improvements can be maintained with as-needed dosing in the second year."