Background and importance Bevacizumab is an anti-vascular endothelial growth factor (anti-VEGF) antibody currently used in ophthalmology as an off-label treatment for age-related macular degeneration, diabetic macular oedema, and oedema secondary to retinal vein occlusion. Despite its off-label use, various studies have shown similar results between bevacizumab and other anti-VEGF treatments. With the availability of a biosimilar with the same presentation and excipients, a switch programme was implemented.

Aim and objectives Compare the effectiveness of bevacizumab Avastin versus biosimilar MVASI in the ophthalmology service.

Material and methods A retrospective observational study analysed 122 patients (65 male, 57 female) who underwent the first intravitreal administration (IVI) between January 2020 and March 2021. Data from best corrected visual acuity (BCVA) and central subfield thickness (CST) were collected. Exclusion criteria were the absence of registration of optical coherence tomography (OCT) and BCVA or failure to comply to three loading dose injectins. The patients were divided into three groups: group 1, 63 patients (3IVI of Avastin), group 2, 30 patients (3 IVI of biosimilar) and group 3, 29 patients (3 IVI, transitioning from Avastin to the biosimilar, either with 1 or 2 Avastin administrations). Manova test was used to determine statistically significant differences among the groups, taking into account the values of BCVA and CST, patients’ age, and the number of days between the last registration prior to the first IVI and the first posterior to the third IVI, without any corrections for differences between groups. T-tests were used to obtain graphic representations of the results.

Results The sample analysed had a mean age of 71.56 years. After three IVI, in group 1, there was 82% of improvement for CST; in group 2 there was 92% and for group 3 there was 84%. MANOVA test was performed showing no statistical significance in BCVA and OCT central thickness difference between the three groups (Wilk’s lambda (p=0.238)) neither between MVASI group with the Avastin group (Hotelling’s T-squared test (p =0.114, equal covariance)).

Conclusion and relevance We found no difference, for the analysed sample, in outcomes and adverse effectes between Avastin and biosimilar MVASI, which proves the possibility of replacing Avastin with the biosimilar MVASI already in use in oncological patients, ensuring a significant cost reduction.

Conflict of interest No conflict of interest