Durability of DR Improvement With As-Needed Ranibizumab
Ophthalmology, May 2019
In this open-label extension of the RIDE and RISE studies, Sun et al. looked at the durability of improvement of diabetic retinopathy (DR) after patients were switched from monthly ranibizumab to pro re nata (PRN) dosing. They found that the DR improvements attained with monthly ranibizumab were maintained in more than 70% of patients after the switch to PRN dosing.
The extension study was a pooled analysis of data for patients with DR and diabetic macular edema (DME) who participated in RIDE or RISE for 36 months. In those studies, patients were assigned randomly (1:1:1) to receive ranibizumab 0.3 mg/month, ranibizumab 0.5 mg/month, or a monthly sham injection. After 24 months, the sham group received ranibizumab 0.5 mg/month.
After 36 months in the core studies, patients in the open-label extension (n = 500) could receive ranibizumab 0.5 mg PRN. DR severity was assessed photographically, using the scale from the Early Treatment Diabetic Retinopathy Study. The primary outcome of the extension study was the change in DR severity from months 36 to 48, according to retreatment status.
Among patients in the open-label extension, 121 (24%) did not require further ranibizumab treatment. DR was evaluable for 367 patients at months 36 and 48. When comparing all three study groups (sham/crossover, ranibizumab 0.3 mg, and ranibizumab 0.5 mg), of the 279 patients who required continuation of ranibizumab, 84% to 94% experienced stability of DR (0- to 1-step change), and 2% had improvement of 2 steps or more. However, 3% to 14% had worsening of at least 2 steps between months 36 and 48. In general, visual improvement was maintained throughout the extension study, regardless of changes in DR severity.
The authors recommend that careful monitoring be part of the long-term management of DR, particularly because the condition often worsens. They added that their findings suggest the possibility of a paradigm shift in DR treatment—that is, focusing on early treatment to reduce DR severity and prevent vision-threatening complications, rather than using a wait-and-watch approach in which treatment is reserved only for advanced eye disease. (Also see related commentary by Robert N. Frank, MD, in the same issue.)
The original article can be found here.