On 3 May, the United States Food and Drug Administration (US-FDA) granted approval to Arexvy, the first respiratory syncytial virus (RSV) vaccine, to prevent lower respiratory tract disorder triggered by the highly contagious virus RSV in people aged sixty years and above. In people of all age groups, this virus can infect lungs and breathing passages. It can cause serious illness in older persons, particularly those who have underlying medical issues including heart or lung disease or compromised immune systems.

The seasonality of RSV circulation normally commences in the autumn and peaks in winter. RSV is a frequent contributor to lower respiratory tract disease, a lung condition that can lead to life-threatening pneumonia and bronchiolitis, in older persons. The U.S. Centers for Disease Control and Prevention (CDC) estimate that RSV causes between 60,000 and 120,000 hospitalizations and 6,000 and 10,000 fatalities among individuals sixty-five and over per year in the U.S. Based on the FDA's examination of data from an ongoing, randomized, placebo-controlled clinical investigation of people sixty years of age and older conducted in the U.S. and globally, Arexvy has been found to be safe and efficacious.

Arexvy's primary clinical research was created to assess the safety and efficiency of a single dose given to people sixty years of age and above. Volunteers will stay in the trial through three RSV seasons for exploring the duration of effectiveness and safety of repeated immunization. For the FDA’s assessment, there was availability of data for Arexvy's single dosage from the first RSV season of the study. A total of 12,500 participants in this research took Arexvy, while another 12,500 received a placebo. Arexvy remarkably minimized the risks of RSV-linked lower respiratory tract illness by 82.6% and the hazard of severe RSV-linked lower respiratory tract illness by 94.1% among participants who were immunized in comparison with placebo recipients.

A subgroup of participants stated that joint stiffness/pain, weariness, injection site pain, muscle soreness, and headache were the most frequent adverse effects experienced by those who received Arexvy. Within 30 days of receiving the immunization, 10 of the subjects in the clinical trial who received Arexvy and 4 of the subjects who received the placebo reported experiencing atrial fibrillation. In two further investigations, Arexvy was administered to almost 2,500 participants who were sixty years of age and above.

 A rare form of inflammation known as acute disseminated encephalomyelitis impacts the spinal cord and brain. It was experienced by two volunteers in one of these studies, in which a few volunteers were given Arexvy concurrently with an FDA-authorized influenza vaccine, seven and twenty-two days, respectively, after getting Arexvy and the influenza vaccine. One of the volunteers with acute disseminated encephalomyelitis passed away. Nine days after getting Arexvy in the other research, one individual had the onset of Guillain-Barré syndrome, a rare condition in which the immune system of the body attacks nerve cells, resulting in muscle weakness and occasionally paralysis.

A postmarketing research will be carried out to investigate the warning signs of significant risks for acute disseminated encephalomyelitis and Guillain-Barré syndrome. The FDA's sustained commitment to support the development of efficacious and safe vaccinations for use in the United States is demonstrated by the approval of this first RSV vaccine, which represents a significant public health accomplishment in the fight against potentially fatal illness.