Randomized Trial of Treat-and-Extend versus Monthly Dosing for Neovascular Age-Related Macular Degeneration: 2-Year Results of the TREX-AMD Study

Abstract

Purpose: To evaluate a prospective treat-and-extend (TREX) management strategy compared with monthly dosing with intravitreal ranibizumab (Lucentis) in neovascular age-related macular degeneration (AMD).

Design: Prospective, randomized, multicenter clinical trial.

Participants: Sixty patients with treatment-naïve neovascular AMD randomized 1:2 to monthly or TREX cohorts.

Methods: Patients with Early Treatment Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (BCVA) of 20/32 to 20/500 (Snellen equivalent) were randomized to receive intravitreal 0.5 mg ranibizumab monthly or, according to a TREX protocol, no less frequently than every 12 weeks. After interval extension, if recurrent exudative disease was identified, this maximum interval between treatments was rechallenged according to a strict prospective protocol.

Main outcome measure: Change in ETDRS BCVA from baseline.

Results: Sixty patients were enrolled and 50 completed month 24, at which point mean ETDRS BCVA letter gains were similar: 10.5 and 8.7 for the monthly and TREX cohorts, respectively (P = 0.64). At month 24, 4 patients (20%) and 12 patients (30%) in the monthly and TREX cohorts, respectively, gained at least 15 letters (P = 0.41). No monthly cohort patient lost more than 2 letters, whereas 5 TREX cohort patients (13%) lost at least 15 letters. Anatomic improvements were similar between the cohorts. Through month 24, the mean number of injections administered was 25.5 (range, 22-27) and 18.6 (range, 10-25) for the monthly and TREX cohorts, respectively (P < 0.001). Among TREX patients completing month 24, 14 (47%) were at an extension interval of 8 weeks or more, and the mean maximum tolerated extension was 8.5 weeks over the course of 2 years. Of the 26 TREX patients (65%) who demonstrated recurrent exudation upon interval extension, the first maximum extension interval was consistent in most eyes (n = 19 [73%]).

Conclusions: The TREX neovascular AMD management protocol used with ranibizumab in the Treat-and-Extend Protocol in Patients with Wet Age-Related Macular Degeneration (TREX-AMD) study resulted in visual and anatomic gains comparable with those obtained with monthly dosing, and most patients randomized to TREX therapy demonstrated a relatively consistent maximum extension interval.