Efficacy of Combining Intravitreal Injections of Ranibizumab with Micropulse Diode Laser Versus Intravitreal Injections of Ranibizumab Alone in Diabetic Macular Edema (ReCaLL): a Single Center, Randomised, Controlled, Non-inferiority Clinical Trial

Background: To evaluate if a combination therapy with micropulse diode laser (MPL) shows non-inferiority on visual acuity (BCVA) within 12 months in comparison to standard therapy, i.e. intravitreal injection of ranibizumab alone.

Setting: Institutional. Prospective randomized single-center trial.

Methods: Patients with diabetic macular edema (DME) received three intravitreal injections of 0.5 mg ranibizumab during the upload phase and were then randomised 1:1 to receive either the same dosage of ranibizumab (0.5 mg) injections pro re nata alone (IVOM-Group; n = 9), or with two additional treatments with micropulse diode laser (IVOM+Laser-Group; n = 10). The primary endpoint was change in BCVA after 12 months. Secondary endpoints were change in central macular thickness and overall number of ranibizumab injections.

Results: BCVA increased significantly in both groups (IVOM: + 5.86, p < 0.001; IVOM+Laser: + 9.30; p < 0.001) with corresponding decrease in central macular thickness (IVOM: - 105 μm, p < 0.01; IVOM+Laser: - 125 μm; p < 0.01). Patients with additional laser treatment had better visual improvement (group comparison p = 0.075) and needed fewer ranibizumab injections (cumulative proportion of injections 9.68 versus 7.46 in IVOM-Group and IVOM+Laser-Group, respectively).

Conclusion: Non-inferiority of combination therapy in comparison to standard therapy alone could be demonstrated. Patients with additional laser therapy needed fewer ranibizumab injections.

Trial Registration: Registered 10 February 2014 on ClinicalTrials.gov; NCT02059772 .