Intravitreal Aflibercept 8 mg for Diabetic Macular Edema: Ninety-Six-Week Results from the Randomized Phase 2/3 PHOTON Trial

Abstract

Purpose: To follow up the previously published comparison of aflibercept 8 mg at extended dosing intervals versus aflibercept 2 mg every 8 weeks (2q8) in patients with diabetic macular edema (DME) through 48 weeks, we now report efficacy, durability, and safety analyses through 96 weeks.

Design: PHOTON (ClinicalTrials.gov identifier, NCT04429503) was a randomized, double-masked, 96-week, noninferiority phase 2/3 trial.

Participants: Patients aged ≥ 18 years with center-involved DME and best-corrected visual acuity (BCVA) of 78 to 24 letters (Snellen equivalent, 20/32-20/320).

Methods: Patients were randomized 1:2:1 to intravitreal aflibercept 2q8, aflibercept 8 mg every 12 weeks (8q12), or aflibercept 8 mg every 16 weeks (8q16) after initial monthly dosing. Dosing intervals for the aflibercept 8-mg groups were modified based on defined criteria.

Main outcome measures: Key outcome measures included change from baseline in BCVA and central retinal thickness (CRT) at week 96, proportion of aflibercept 8 mg-treated patients whose randomized dosing intervals were maintained or extended, and safety outcomes.

Results: Overall, 658 patients (8q12, n = 328; 8q16, n = 163; 2q8, n = 167) received treatment, and 534 completed week 96. Mean (standard deviation [SD]) BCVA change from baseline at week 96 was comparable for 8q12 and 8q16 versus 2q8 at week 96 (+8.8 [9.9] and +7.5 [9.9] vs. +8.4 [11.1] letters). Mean (SD) CRT change from baseline was -185.3 (146.5) μm, -155.0 (144.9) μm, and -187.0 (146.3) μm for 8q12, 8q16, and 2q8, respectively. Mean number of active injections through week 96 in the 8q12, 8q16, and 2q8 groups was 9.5, 7.8, and 13.8, respectively. Of patients completing week 96, 88% and 83% randomized to 8q12 and 8q16, respectively, maintained ≥ 12-week or ≥ 16-week dosing intervals, 43% and 47% qualified for ≥ 20-week dosing intervals, and 24% and 32% qualified for 24-week dosing intervals at week 96. Incidence of ocular treatment-emergent adverse events in the study eye was similar across groups (37.1%-45.4%).

Conclusions: Aflibercept 8 mg at extended dosing intervals maintained visual and anatomic improvements and similar safety to aflibercept 2 mg every 8 weeks with fewer injections over 96 weeks in patients with DME.

Financial disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Keywords: Aflibercept 8 mg; Diabetic macular edema; Durability; Efficacy; Safety.