Japan's Ministry of Health, Labour and Welfare (MHLW) has granted regulatory approval for Chugai Pharmaceutical's Vabysmo (faricimab) for the treatment of macular edema associated with retinal vein occlusion (RVO). The approval, announced on March 26, 2024, positions Vabysmo as the first bispecific antibody approved in Japan for this vision-threatening condition.
Dr. Osamu Okuda, President and CEO of Chugai Pharmaceutical, expressed enthusiasm about the approval: "I'm very pleased to have obtained approval for Vabysmo, the only bispecific antibody in the ophthalmology field, for additional indication of macular edema associated with RVO. Treatment with Vabysmo is expected to improve and maintain vision in patients with RVO, a disease that can severely affect vision and lead to blindness."
Mechanism of Action and Clinical Evidence
Vabysmo represents a significant advancement in ophthalmology as the first bispecific antibody in the field. The drug works by simultaneously targeting and inhibiting two distinct signaling pathways linked to retinal conditions: angiopoietin-2 (Ang-2) and vascular endothelial growth factor-A (VEGF-A). These proteins contribute to vision loss by destabilizing blood vessels, promoting the formation of leaky new vessels, and increasing inflammation. By blocking both pathways, Vabysmo is designed to stabilize blood vessels and reduce retinal damage.
The approval is supported by data from two global Phase III clinical trials: BALATON, which focused on branch retinal vein occlusion, and COMINO, which evaluated central retinal or hemiretinal vein occlusion. Chugai participated in both studies, which demonstrated that Vabysmo rapidly improved vision and reduced retinal fluid in people with RVO.
Dosage and Administration
According to the approval, patients will receive 6 mg (0.05 mL) of faricimab administered via intravitreal injection once every four weeks or more. This treatment regimen aims to improve and maintain vision in patients suffering from macular edema associated with RVO.
Understanding Retinal Vein Occlusion
RVO represents the second most common cause of vision loss due to retinal vascular diseases, affecting an estimated 28 million adults globally and approximately 1.66 million adults in Japan. The condition primarily affects individuals aged 60 or older and can lead to severe and sudden vision loss.
The disease occurs when a vein carrying blood away from the retina becomes blocked, restricting normal blood flow in the affected retina. This blockage results in ischemia, bleeding, fluid leakage, and macular edema (swelling of the macula). Patients typically experience sudden, painless vision loss in the affected eye.
There are two main types of RVO:
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Branch Retinal Vein Occlusion (BRVO): More common, affecting over 23 million people globally. BRVO occurs when one of the four smaller 'branches' of the main central retinal vein becomes blocked.
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Central Retinal Vein Occlusion (CRVO): Less common, affecting more than four million people worldwide. CRVO occurs when the eye's central retinal vein becomes blocked.
Global Availability and Regulatory Status
Vabysmo has already gained approval in more than 90 countries worldwide, including the United States, Japan, the United Kingdom, and the European Union, for the treatment of neovascular or 'wet' age-related macular degeneration and diabetic macular edema. The addition of the RVO indication in Japan expands the drug's therapeutic potential to address another significant cause of vision loss.
Currently, macular edema due to RVO is typically treated with intravitreal injections of anti-VEGF therapies. Vabysmo's dual mechanism of action targeting both VEGF-A and Ang-2 represents a novel approach to treating this condition.
Future Outlook
Chugai Pharmaceutical has committed to continuing to provide information on the proper use of Vabysmo to contribute to the treatment of patients with macular edema associated with RVO. As the first bispecific antibody approved for this indication in Japan, Vabysmo may offer new hope for patients suffering from this vision-threatening condition.
The approval of Vabysmo for RVO in Japan marks another milestone in the evolution of treatments for retinal vascular diseases, potentially offering improved outcomes for patients with limited therapeutic options.
