Biosimilar Bevacizumab Effectively Treats Macular Edema Due to Retinal Diseases

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A new retrospective analysis suggests a biosimilar product of bevacizumab (Zybev) administered intravitreally to patients with macular edema due to retinal diseases was safe and effective over 6 weeks.¹

Results showed treatment with the anti-vascular endothelial growth factor (anti-VEGF) biosimilar improved both best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) parameters in those with retinal diseases responsible for macular edema, including age-related macular degeneration, diabetic macular edema, and retinal vein occlusion.

“The short-term results of our study with a single injection dose have shown statistically significant improvement in terms of reduction of central subfield thickness (CST), average cube thickness and volume, and improvement in BCVA,” wrote the investigative team, led by Professor Sanjiv K. Gupta, from the ophthalmology department at King George Medical University.

Bevacizumab, a full-length, humanized monoclonal IgG1 antibody that targets all biologically active sub-types of VEGF-A, has not been approved for ophthalmological use, but prior clinical trials have proven it non-inferior to ranibizumab in terms of efficacy and safety. A biosimilar to bevacizumab, Zybev(Z), was approved for use in non-small cell lung cancer in India following phase 3 research. However, the current literature is insufficient in establishing the role of biosimilar products of bevacizumab for use in retinal diseases.²

Thus, the current retrospective analysis investigated the efficacy and safety profile of the bevacizumab biosimilar for the treatment of macular edema due to various retinal diseases. Medical records of all patients 18 - 80 years old with macular edema due to retinal diseases who received intravitreal injections of biosimilar bevacizumab at the tertiary eye care center were studied between September 2021- April 2022.

Patients underwent ophthalmological examination including measurement of BCVA, examination of the anterior segment by slit-lamp biomicroscopy, intraocular pressure measurement, examination of the fundus by indirect ophthalmoscopy, macular evaluations by spectral-domain OCT, and fundus photography. The primary outcome was the change in CST (µm) before and after intravitreal biosimilar bevacizumab over the 6-week period; secondary outcomes measured were BCVA, average cub thickness and volume, and any adverse effects after injection.

A total of 104 patients, with a mean age of 53 years and 53.8% males, were included in the analysis. The analysis showed baseline BCVA was 1.32 ± 0.70 logMAR, which improved to 1.13 ​​± 0.71 at 6 weeks after a single injection (P < .05). The mean CST significantly reduced from 429.26 ± 204.30 pre-intravitreal biosimilar bevacizumab to 302.26 ± 104.50 post-injection (P <.05).

Moreover, the analysis showed the mean average cube thickness (µm) decreased from 11.85 ± 1.96 pre-injection to 10.52 ± 1.75 post-injection and the mean average cube volume (mm3) decreased from 329.30 ± 54.35 to 302.23 ± 49.56 (P < 0.05). Over the follow-up period, none of the eyes developed intraocular inflammation and/or endophthalmitis. In addition, the worsening of systemic disease or serious adverse events were not reported over the 6 weeks.

Gupta and colleagues noted the small sample size and short-term outcome of 6 weeks for the analysis as a limitation of the analysis, as well as the study’s retrospective nature and lack of data regarding the metabolic profiles of the patients.

“However, given the safety and efficacy of the biosimilar products as per this study, further clinical trials comparing the pharmacokinetics of reference and biosimilar medication are necessary, as well as at least one prospective, multi-centric randomized controlled trial with repeat injections and a larger sample size to demonstrate the long-term clinical efficacy and safety.”

References

1. Agarwal R, Gupta SK, Agrawal S. Efficacy and safety analysis of intravitreal bio-similar products of bevacizumab in patients with macular edema because of retinal diseases. Indian J Ophthalmol. 2023;71(5):2066-2070. doi:10.4103/ijo.IJO_1748_22
2. Sharma A, Kumar N, Kuppermann BD, Bandello F, Loewenstein A. Understanding biosimilars and its regulatory aspects across the globe: An ophthalmology perspective. Br J Ophthalmol 2020;104:2–7