Non-Responders to Intravitreal Ranibizumab in Subfoveal Choroidal Neovascularization Secondary to Age-Related Macular Degeneration.

AIM: Evaluation of the proportion of patients affected by subfoveal choroidal neovascularization secondary to age-related macular degeneration who are non-respondent to intravitreal ranibizumab injections (IVRI).
METHODS: Patients received 3 monthly IVRI, with monthly retreatments, in accordance with a pro re nata scheme (fluid on optical coherence tomography, leakage on fluorescein angiography, new haemorrhages). Non-responders were classified as follows: functional non-responder (best-corrected visual acuity worsening by a minimum of 2 ETDRS lines); anatomical non-responder (central foveal thickness not decreasing by at least 10% compared with baseline value); complete non-responder (both anatomical and functional non-responder criteria apply). PRIMARY OUTCOME MEASURE: identification of the proportion of non-responders.
RESULTS: Four patients (7%) were functional non-responders at the 1-month examination, and 5, 5 and 7% at the 2-, 3- and 6-month examinations, respectively. Two of 4 initial non-responders were reclassified as responders during the 6-month follow-up. Twenty-three eyes (43%) were anatomical non-responders at the 1-month visit, and 32, 28 and 21% at 2, 3 and 6 months, respectively. Sixteen of 23 (70%) initially non-respondent eyes became respondent over the follow-up. Two eyes (4%) were classified as complete non-responders after 1 month. Non-responders amounted to 4, 0 and 2% at the 2-, 3- and 6-month examinations, respectively. No initially complete non-responding eye remained so over the follow-up.
CONCLUSION: Data indicate a low proportion of functional and anatomical non-responders to IVRI. Further studies are warranted providing a better definition of non-responder and a clearer picture of the magnitude of response, when present.