Propranolol 0.1% eye micro-drops in newborns with retinopathy of prematurity: a pilot clinical trial

BACKGROUNDOral propranolol reduces retinopathy of prematurity (ROP) progression, although not safely. This study evaluated safety and efficacy of propranolol eye micro-drops in preterm newborns with ROP.METHODSA multicenter open-label trial, planned according to the Simon optimal two-stage design, was performed to analyze safety and efficacy of propranolol micro-drops in newborns with stage 2 ROP. To this end, hemodynamic and respiratory parameters were monitored, and blood samples were collected weekly, for three weeks. Propranolol plasma levels were also monitored. The progression of the disease was evaluated with serial ophthalmologic examinations.RESULTSTwenty-three newborns were enrolled. Since the fourth of the first 19 newborns enrolled in the first stage of the study showed a progression to stage 2 or 3 with plus, the second stage was prematurely discontinued. Even though the objective to complete the second stage was not achieved, the percentage of ROP progression (26%) was similar to that obtained previously with oral propranolol administration. However, no adverse effects were observed and propranolol plasma levels were significantly lower than those measured after oral administration.CONCLUSIONPropranolol 0.1% eye micro-drops are well tolerated, but not sufficiently effective. Further studies are required to identify the optimal dose and administration schedule.