Long-term clinical effects of intravitreal injections of conbercept for the treatment of choroidal neovascularization in patients with pathological myopia

AIM: To observe the long-term clinical efficacy of intravitreal injections of conbercept, a novel vascular growth factor inhibitor, for the treatment of pathological myopia choroidal neovascularization (PM-CNV).
METHODS: A total of 67 eyes (from 67 patients; mean age, 54.90±12.7y) with PM-CNV were retrospectively researched. Based on the different schemes used for the administration of the drug, the patients were divided into two groups: group A (n=35; average age, 53.31±13.6y; average diopter, 9.25±1.72 D), which received only one injection of pro re nata (PRN; 1+PRN regimen), and group B (n=32; average age, 56.49±11.8y; average diopter, 9.63±2.24 D), which received one injection per month for 3mo (3+PRN regimen). Best-corrected visual acuity (BCVA) analysis, intraocular pressure (IOP) examination, slit-lamp microscopy, fundus examination and optical coherence tomography were performed at each follow-up. The recurrence and treatment times of CNV were recorded. The patients were followed up for at least 12mo.
RESULTS: The BCVA was increased in 29 eyes (82.9%) in group A and 30 eyes (93.75%) in group B; no increase or decrease was observed in 6 (17.1%) and 2 (6.25%) eyes in groups A and B, respectively. The BCVA (logMAR) values before treatment (0.67±0.48 and 0.71±0.56) were significantly higher than those 12mo after treatment (0.31±0.26 and 0.33±0.17) in groups A and B, respectively (P<0.05). The mean central macular thickness (CMT) values had significantly decreased from 346.49±65.99 and 360.10±82.31 μm at baseline to 257.29±40.47 and 251.97±48.26 μm in groups A and B, respectively, after 12mo of treatment. A total of 21 eyes in group A needed reinjection (60%; average number of injections, 2.51±0.98); the corresponding values in group B were 6 eyes (18.75%; average number of injections, 3.74±1.22). There were no adverse ocular and systemic complications during the treatment and follow-up.
CONCLUSION: Intravitreal injection of conbercept with 1+PRN or 3+PRN improve the visual acuity, reduce macular edema and reduce the level of CMT in patients with PM-CNV. The 3+PRN regimen demonstrates a lower recurrence rate of CNV than the 1+PRN regimen, but requires more treatment. However, both treatment regimens demonstrate long-term safety and efficacy for the treatment of PM-CNV.