Intravitreal injection of bevacizumab proved superior to conventional laser therapy for preventing recurrence of retinopathy of prematurity while averting many of the complications of laser treatment.
Intravitreal injection of bevacizumab proved superior to conventional laser therapy for preventing recurrence of retinopathy of prematurity (ROP) while averting many of the complications of laser treatment.
A clinical trial comparing the 2 treatments found such a dramatic advantage to bevacizumab, especially for disease of zone I, that one ophthalmologist wrote in an editorial that intravitreal bevacizumab should become the treatment of choice for zone I ROP.
The findings were published in the New England Journal of Medicine by Helen A. Mintz-Hittner, MD, and colleagues at the Robert Cizik Eye Clinic at the University of Texas Health Science Center at Houston-Medical School.
The study compared the 2 treatments for stage 3+ retinopathy of prematurity in zone I or zone II, with the zones indicating the area of vascularization. Zone I disease is the most difficult to treat, said Mintz-Hittner and has a high incidence of recurrence that requires retreatment. Stage 3 disease is usually when ROP is treated; stage 3+ disease indicates that dilated veins and tortuous arteries invade 2 or more quadrants of the eye.
"We picked the patients who were the most vulnerable; who had the worst cases of ROP: zone I's and the small zone II's, the posterior zone II's as we call them," said Mintz-Hittner, Alfred W. Lasher professor of ophthalmology.
"It was the first time we were studying this so we wanted to pick the ones in whom we could justify [the treatment] because they have poor outcomes most often. Zone I is the worst kind of disease you can have, especially a form of the disease called aggressive posterior ROP."
Fifteen centers participated in the trial, in which 150 infants with a gestational age of 30 weeks or less were randomized to either intravitreal bevacizumab or laser therapy. Sixty-seven infants had zone I disease; 83 had zone II posterior disease. Seven babies who died were not included in the final analysis.
Recurrences far fewer with bevacizumab
The rate of recurrence, the primary outcome of the study, was 26% in the group randomized to conventional laser treatment compared with only 6% in the infants randomized to bevacizumab, a reduction in risk of 83% with bevacizumab (P=.002).
When the outcome was stratified by zone, the rate of recurrence with zone I disease was 42% with laser therapy and 6% with bevacizumab, corresponding to a 91% reduction with bevacizumab (P=.003). The rate of recurrence with zone II posterior disease alone was not significantly different between treatment types (12% with laser therapy vs 5% with bevacizumab), although the trend again was in favor of bevacizumab.
"The zone II's didn't recur very often so we didn't get significance," she said. "I think it would take a larger number of patients to get significance. I think you would get significance."