A comprehensive real-world safety analysis of Mvasi (bevacizumab-awwb) has provided reassuring evidence for ophthalmologists using this oncology-approved biosimilar off-label to treat sight-threatening retinal conditions. The study, conducted across South Australia's public hospital system, analyzed 6,230 intravitreal injections administered to 1,682 eyes between May 2022 and May 2024, finding safety outcomes comparable to reference bevacizumab.
The retrospective review documented exceptionally low rates of serious adverse events, with only 3 cases each of bacterial endophthalmitis and uveitis (0.05% each), and no cases of retinal vasculitis. These complication rates align with established safety profiles for reference bevacizumab and other anti-VEGF agents, according to the study authors.
Addressing Critical Safety Concerns
The research addresses significant ethical and safety concerns surrounding off-label biosimilar use in ophthalmology. As the study authors noted, "While anti-VEGF [vascular endothelial growth factor] biosimilars approved for oncology may offer cost savings, their use in ophthalmology without dedicated trials raises ethical and safety concerns. Off‐label adoption without ophthalmic‐specific studies risks exposing patients to harm."
The findings are particularly relevant for Australia, where clinicians have increasingly turned to Mvasi following the loss of subsidized Avastin from the Pharmaceutical Benefits Scheme in 2021 due to commercial reasons. Mvasi has since become a primary anti-VEGF therapy in public hospitals for conditions including neovascular age-related macular degeneration and diabetic macular edema.
Study Population and Treatment Patterns
The study population had a mean age of 69.8 years, with patients receiving an average of 3.7 injections per eye. The most frequent treatment indications were neovascular age-related macular degeneration (33.8% of injections), diabetic macular edema (26.2%), and retinal vein occlusions.
"These complication rates are consistent with what we see with reference bevacizumab and other anti-VEGF agents," the authors noted. "This supports Mvasi as a practical alternative for continued high-quality retinal care in Australia."
Global Implications for Biosimilar Adoption
The implications extend beyond Australia's healthcare system. In the United States, while biosimilars for ranibizumab and aflibercept have entered the ophthalmology market, bevacizumab biosimilars such as Mvasi are not yet FDA approved for intravitreal use. Nevertheless, some physicians prescribe them off-label due to affordability and access considerations.
"Real-world data like this is critical, especially for off-label biosimilar use," said one biosimilar market analyst. "It helps build clinician and regulatory confidence, particularly in therapeutic areas like ophthalmology where the margin for error is very small."
Evidence-Based Practice Considerations
Prior to this study, safety data for intravitreal Mvasi had been limited, as most research centered on its systemic use in oncology. The findings are especially timely given global interest in expanding biosimilar use to curb drug costs while maintaining patient safety.
The study authors emphasized the importance of evidence-based practice, stating that "Healthcare providers must prioritise evidence‐based practice over cost incentives, advocating for research that confirms the suitability of these biosimilars for ophthalmic use, with patient safety as the primary consideration."
The research highlights the critical importance of continued postmarket surveillance to detect rare complications and evaluate biosimilars in real-world clinical settings. As biosimilar adoption grows globally, especially in cost-sensitive markets, robust safety data will be crucial for integrating these products into routine care.
With mounting evidence supporting its safety profile, Mvasi could help fill the gap left by Avastin and ensure continued access to sight-saving treatments, particularly in public health systems where affordability and availability are paramount.
