Comparing alternative ranibizumab dosages for safety and efficacy in retinopathy of prematurity: A randomized clinical trial

IMPORTANCE Anti-vascular endothelial growth factor (VEGF) therapies are a novel treatment option in retinopathy of prematurity (ROP). Data on dosing, efficacy, and safety are insufficient. OBJECTIVE To investigate lower doses of anti-VEGF therapy with ranibizumab, a substance with a significantly shorter systemic half-life than the standard treatment, bevacizumab. DESIGN, SETTING, AND PARTICIPANTS This randomized, multicenter, double-blind, investigator-initiated trial at 9 academic medical centers in Germany compared ranibizumab doses of 0.12mg vs 0.20mg in infants with bilateral aggressive posterior ROP; ROP stage 1 with plus disease, 2 with plus disease, or 3 with or without plus disease in zone I; or ROP stage 3 with plus disease in posterior zone II. Patients were recruited between September 2014 and August 2016. Twenty infants were screened and 19 were randomized. INTERVENTIONS All infants received 1 baseline ranibizumab injection per eye. Reinjections were allowed in case of ROP recurrence after at least 28 days. MAIN OUTCOMES AND MEASURES The primary end pointwas the number of infants who did not require rescue therapy at 24 weeks. Key secondary end points included time-to-event analyses, progression of physiologic vascularization, and plasma VEGF levels. Stages of ROP were photodocumented and reviewed by an expert committee. RESULTS Nineteen infants with ROP were enrolled (9 [47.4%] female; median [range] postmenstrual age at first treatment, 36.4 [34.7-39.7] weeks), 3 of whom died during the study (1 in the 0.12-mg group and 2 in the 0.20-mg group). Of the surviving infants, 8 (88.9%) (17 eyes [94.4%]) in the 0.12-mg group and 6 (85.7%) (13 eyes [92.9%]) in the 0.20-mg group did not require rescue therapy. Both ranibizumab doses were equally successful in controlling acute ROP (Cochran-Mantel-Haenszel analysis; odds ratio, 1.88; 95%CI, 0.26-13.49; P = .53). Physiologic intraretinal vascularization was superior in the 0.12-mg group. The VEGF plasma levels were not systematically altered in either group. CONCLUSIONS AND RELEVANCE This pilot study demonstrates that ranibizumab is effective in controlling acute ROP and that 24%of the standard adult dose (0.12mg) appears equally effective as 40% (0.20mg). Superior vascularization of the peripheral retina with 0.12mg of ranibizumab indicates that the lower dose may be favorable. Unchanged plasma VEGF levels point toward a limited systemic drug exposure after ranibizumab.