FDA Approves Arexvy, the Initial RSV Vaccine

Great news from the U.S. Food and Drug Administration! They've given their seal of approval to Arexvy, the very first vaccine against respiratory syncytial virus (RSV) in the United States. Specifically designed to prevent lower respiratory tract disease triggered by RSV, it's aimed at individuals aged 60 and over. The reason? Older adults, especially those with conditions like heart or lung disease or compromised immune systems, are at a higher risk of serious RSV-related illness.

RSV: What's the Buzz?

RSV or respiratory syncytial virus is a super-contagious bug that targets the respiratory system and can affect anyone, regardless of age. It shows up seasonally, usually starting in the fall and peaking in the winter. Among the elderly, RSV commonly causes lower respiratory tract disease (LRTD), which impacts the lungs and can lead to severe conditions like pneumonia and bronchiolitis. As per the U.S. Centers for Disease Control and Prevention (CDC), RSV is the culprit behind around 60,000-160,000 hospitalizations and 6,000-10,000 deaths each year. Adults at the highest risk for severe RSV infection include older adults, particularly those 65 years and older, adults with chronic heart or lung disease, and adults with weakened immune systems.

How Safe and Effective is Arexvy?

The FDA assessed the safety and effectiveness of Arexvy based on an ongoing clinical study conducted domestically and internationally. This randomized, placebo-controlled study involved individuals aged 60 and above. About 12,500 participants were given Arexvy, while a similar number received a placebo. The vaccine showed a significant risk reduction of 82.6% for developing RSV-associated LRTD and a risk reduction of 94.1% for severe RSV-associated LRTD.

Any Side Effects with Arexvy?

The trial reported the most common side effects of Arexvy to be pain at the injection site, fatigue, muscle pain, headaches, and joint pain. Within 30 days of vaccination, 10 participants who received Arexvy and four who got the placebo reported atrial fibrillation.

Also, out of 2,500 people who received both Arexvy and an FDA-approved flu vaccine, two individuals developed acute disseminated encephalomyelitis (ADEM), a rare inflammation of the brain and spinal cord, 7 and 22 days after getting the vaccines. Additionally, one participant developed Guillain-Barré syndrome, a rare disorder causing muscle weakness and paralysis due to immune system damage to nerve cells, nine days post receiving Arexvy.

The FDA has requested the company to conduct a post-marketing study to assess potential serious risks related to Guillain-Barré syndrome and ADEM, although it's not a mandatory requirement by the FDA. Plus, the company has pledged to evaluate atrial fibrillation in the post-marketing study.