Eric Schneider, MD
Diabetic macular edema (DME) patients using aflibercept 8mg are maintaining long-term visual and anatomical improvements even with extended dosing intervals. This was revealed in a recent study presented at the 43rd Annual Scientific Meeting of the American Society of Retina Specialists in Long Beach, California.
The study, presented by Eric Schneider, MD, explored results from the PHOTON extension study. The original PHOTON trial, a double-masked, active-controlled study, compared aflibercept 8mg administered every 12 weeks (8q12) and every 16 weeks (8q16) against aflibercept 2mg every 8 weeks (2q8). Both aflibercept 8mg regimens were given after three initial monthly doses, while the aflibercept 2mg regimen received five initial monthly doses.
By the two-year mark, the 8q16 group received notably fewer injections (7.8 compared to 9.5 in the 8q12 group and 13.8 in the 2q8 group). This group also saw a lower percentage of patients losing 15 or more letters of vision (1.2% versus 3.4% and 3.6%). However, the 8q16 group showed slightly lower improvements in best-corrected visual acuity (BCVA) by 7.5 letters, compared to 8.8 in the 8q12 group and 8.4 in the 2q8 group.
Importantly, 93% of patients in the combined aflibercept 8mg groups had a last assigned dosing interval of at least 12 weeks at week 96. The extension study, which followed patients for up to 156 weeks, further assessed the efficacy, durability, and safety of this treatment.
Following week 96, patients in the 8q12 and 8q16 groups continued receiving aflibercept 8mg. Those originally in the 2q8 group were switched to aflibercept 8mg with 12-week dosing intervals. Starting from week 100, doctors could adjust dosing intervals based on specific patient criteria.
At the 156-week mark, both the aflibercept 8mg and the switched groups maintained their visual and anatomical improvements from week 96. The group that switched to aflibercept 8mg showed a significantly slower rate of fluid reaccumulation eight weeks after their initial 8mg injection compared to the rate seen eight weeks after their 2mg injections in the first two years.
Among the patients in the aflibercept 8mg group who completed the extension, 45% had a last completed dosing interval of 20 weeks or more, and 48% had a last assigned interval of 20 weeks or more. In the switched group, 83% had a last assigned interval of at least 12 weeks by week 156. No new safety concerns were identified throughout the extension period.
“The achievement of extended dosing intervals with aflibercept 8mg in the vast majority of patients, together with the slower fluid reaccumulation observed following a switch from aflibercept 2mg to 8mg, supports the longer duration of action of aflibercept 8mg versus 2mg,” stated Schneider and colleagues.
