• Written By: Rahul Khurana, MD

    This analysis of data from the large, randomized, phase 3 HARBOR study found that intravitreal injections of ranibizumab 0.5 mg and 2.0 mg, given monthly or PRN, yielded similar visual results at 24 months.

    Investigators randomized 1,098 patients ≥ 50 years of age with treatment-naïve subfoveal wet AMD to receive intravitreal injections of ranibizumab 0.5 mg or 2.0 mg monthly or PRN after three monthly loading doses.

    At month 24, the mean BCVA change in letters from baseline was +9.1 in the 0.5 mg monthly group, +7.9 in the 0.5 mg PRN group, +8.0 in the 2.0 mg monthly group and +7.6 in the 2.0 mg PRN group. The mean number of ranibizumab injections through month 24 was 21.4, 13.3, 21.6 and 11.2, respectively; 5.6 and 4.3 mean injections were required in year two in the 0.5 mg and 2.0 mg PRN groups, respectively. The average treatment interval in the 0.5 mg PRN group was 9.9 weeks after the loading doses, and 93% of these patients did not require monthly dosing.

    The authors note that all four treatment groups maintained their visual and anatomic improvements, on average, between months 12 and 24 of the study. Over two years, the 2.0 mg dose ranibizumab did not show any clinically meaningful difference in efficacy, durability or safety compared with the 0.5 mg dose.

    They write that the PRN administration of ranibizumab 0.5 mg and 2.0 mg was efficacious, with safety profiles consistent with those of previous ranibizumab studies in wet AMD, and provided durable results with less frequent dosing.

    They note that the 0.5 mg PRN group had the least amount of visual change from months 12 to 24 (−0.3 letters). Since most patients in this group did not require monthly dosing, an individualized treatment approach with this dosage using visual acuity and SD-OCT–guided re-treatment criteria may be the most appropriate for most patients with wet AMD.

    How often do you dose ranibizumab for wet AMD?