The Diabetic Retinopathy Clinical Research Network One-Year Results from a Randomized Clinical Trial Evaluating Intravitreal Ranibizumab or Saline for Vitreous Hemorrhage from Proliferative Diabetic Retinopathy Abdhish Bhavsar, MD for the Diabetic Retinopathy Clinical Research Network Supported through a cooperative agreement from the National Eye Institute and the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Department of Health and Human Services; EY14231 and EY018817
Financial Disclosures • Research Grant Support: DRCR, Genentech
Study Objectives • To determine if intravitreal injections of ranibizumab decrease the proportion of eyes in which vitrectomy is performed by 16 weeks compared with saline injections in eyes presenting with vitreous hemorrhage from PDR. • Note: This trial was not a comparison of anti-VEGF with observation or sham injection; rather the trial was a comparison of intravitreal anti-VEGF with intravitreal saline injection • To assess the efficacy and safety through 16 weeks, and safety through 52 weeks, of anti-VEGF therapy as treatment for vitreous hemorrhage due to PDR. 3
Study Design, Enrollment, Follow-up Randomized, Multi-center ,Double Masked Trial • At least one eye that met all of the following criteria: • Vitreous hemorrhage causing vision impairment, presumed to be from PDR, and precluding completion of PRP • Immediate vitrectomy is not required • Visual acuity is light perception or better • No prior anti-VEGF treatment for VH Primary Outcome: Treatment group comparison of the cumulative probabilities of vitrectomy by 16 weeks of randomization. 4
Study Enrollment 261 Eyes Randomized (61 Sites) • Intravitreal Injection of 0.5 ranibizumab • N = 125 • Intravitreal Injection 0.9% sodium chloride • N = 136 12 Week Visit Completion (primary outcome) = 95% Overall* (96% Ranibizumab Injection; 95% Saline Injection) 52 Week Visit Completion (additional safety outcomes) (80% Ranibizumab Injection; 83% Saline Injection) * One death occurred prior to the 12 week visit and 5 deaths were reported between 12 to 52 weeks of study follow-up. 5
Follow-up Schedule Phase 2 Phase 1 4 WK VISIT Treatment for VH at investigator discretion 8 WK VISIT 26 WK Phone Call 12 WK VISIT 16 WK Primary Outcome Time Point 52 WK VISIT 6
Study Treatment • Follow-up injections performed at 4 and 8 weeks unless: • Vitreous hemorrhage had cleared enough to complete PRP or Vitrectomy had been performed. • All eyes were to be treated with complete PRP as soon as possible. • Prior to the 16 week endpoint, the decision to perform vitrectomy was based on study guidelines. • Further treatment following the 16 week endpoint was at Investigator discretion. • PRP was to be initiated as soon as possible 7
Vitrectomy Primary Outcome 10
ConclusionsPrimary Outcome • This study suggests little likelihood of a clinically important difference between ranibizumab and saline on the rate of vitrectomy by 16 weeks in eyes with VH from PDR. • As a result of having substantially overestimated the control group rate when estimating sample size, the study may not have been sufficiently powered to detect a treatment group difference. 12
Vitrectomy Secondary Outcome 13
Cumulative Probability of Vitrectomy by 52 Weeks No follow-up contact was performed between 16 to 52 weeks
“Complete” Panretinal Photocoagulation Secondary Outcome 15
Cumulative Probability of “Complete” PRP (in absence of vitrectomy) by 16 Weeks
Cumulative Probability of “Complete” PRP (in absence of vitrectomy) by 52 Weeks No follow-up contact was performed between 16 to 52 weeks.
Visual Acuity at Follow-up Visits Secondary Outcome 18
Mean Change in Visual Acuity from Baseline Prior to 16 Weeks †P=0.04 † Treatment comparison for the mean change in visual acuity at the 12 week visit was performed using a longitudinal mixed model adjusting for baseline visual acuity. 19
Mean Change in Visual Acuity from Baseline – Up to 52 weeks No follow-up contact was performed between 16 weeks to 52 weeks. 20
ConclusionsSecondary Outcomes • By 52 weeks, the rate of vitrectomy remained similar between the two treatment groups with over 1/3 of eyes in both groups undergoing vitrectomy. • Short term secondary outcomes including visual acuity improvement, increased PRP completion rates, and reduced recurrent VH rates suggest biologic activity of ranibizumab by 16 weeks of study follow-up.
ConclusionsSecondary Outcomes • The ability to perform PRP appeared slightly better in the ranibizumab group throughout one-year of follow-up; however the improvement in mean visual acuity observed at 12 weeks was no longer present at 52 weeks. • It should be noted that treatment after the 16 week endpoint was at the investigator’s discretion.
Ocular Adverse Events of Interest ¥ Treatment comparison for recurrent vitreous hemorrhage was performed using Fisher Exact test (P-value = 0.01) 24
Conclusions Safety Outcomes • Intravitreal ranibizumab does not appear to increase the risk of retinal detachment throughout one-year of study follow-up. • The evaluation of intravitreal saline versus ranibizumab given at baseline, 4 and 8 weeks after randomization in eyes with vitreous hemorrhage, showed no difference in safety between the two treatment groups at 52 weeks. 25
Discussion • Whether vitrectomy rates after saline or ranibizumab are different than observation alone cannot be determined from this study. • Further follow-up on these two groups indicate a relatively high incidence of vitrectomy in both groups by one year. 26