Novartis has terminated its three clinical trials of its controversial vascular endothelial growth factor (VEGF) inhibitor Beovu (brolucizumab-dbll) amid vision-loss concerns.

The company’s phase 3 Merlin trial was evaluating the safety and efficacy of 6mg Beovu injections for the treatment of wet age-related macular degeneration (AMD) with a four-weekly dose following the loading period. The trial was discontinued due to 4.8% of the Beovu cohort experiencing vision loss and 9.3% of them suffering intraocular inflammation, compared with 1.7% and 4.5%, respectively, with Eylea (aflibercept)-treated patients. However, Novartis noted that, “When used on a two- to three-month interval following the loading phase, Beovu remains an important and effective treatment option for appropriate patients with wet AMD.”

The company also stopped its Raptor and Raven studies, which were evaluating Beovu’s efficacy in treating retinal vein occlusion at the same dosing rate. As part of the announcement, Novartis advised physicians not to treat patients with Beovu 6mg at intervals less than two months beyond the first three loading doses.

Although Beovu received US Food and Drug Administration (FDA) approval in October 2019, The American Society of Retinal Specialists (ASRS) raised concerns in February 2020, due to 14 cases of vasculitis, 11 of which were diagnosed as occlusive retinal vasculitis. At the time, Novartis defended the drug, saying, “The safety of Beovu has been demonstrated in an extensive phase 3 programme, including more than 1,800 patients worldwide across 400 study sites.”