**Merck Announces Positive Trial Results for RSV Treatment in Infants**

Merck has reported encouraging outcomes for its experimental treatment aimed at protecting infants from respiratory syncytial virus (RSV). The treatment showed significant promise in a mid- to late-stage trial, positioning Merck as a potential new entrant in the RSV treatment market, a virus that leads to hundreds of infant deaths annually.

Merck disclosed this progress on Thursday, emphasizing that the experimental treatment, clesrovimab, demonstrated positive results by significantly reducing RSV-related complications during trials. These advancements could make Merck a formidable competitor in the RSV treatment market, which has a significant impact on older adults and infants alike, causing thousands of deaths among the former and hundreds among the latter each year. Complications from RSV are the primary reason for hospitalizing newborns, suggesting that Merck's new treatment could be a vital addition to current therapeutic options if it secures approval.

The company is currently engaged in discussions with regulatory bodies worldwide and aims to make this treatment available for infants by the 2025 to 2026 RSV season. This announcement was made following the presentation of trial data at the medical conference IDWeek in Los Angeles. The trial evaluated the safety and efficacy of a single dose of clesrovimab in both preterm and full-term infants entering their first RSV season.

According to Merck, the treatment reduced RSV-related hospitalizations by more than 84% and selected lower respiratory infections requiring hospitalization by 90% in comparison to a placebo among infants up to five months old. Additionally, clesrovimab lowered the incidence of lower respiratory infections necessitating medical attention by over 60% relative to a placebo through the same period. The consistent results were noted at both the five-month and six-month intervals. Importantly, the frequency of adverse and serious side effects was similar between the treatment group and the placebo group, and no deaths related to the treatment or RSV were recorded in the study.

Dr. Octavio Ramilo, chair of the Department of Infectious Diseases at St. Jude's Children's Research Hospital and an investigator on the trials, highlighted the potential impact of clesrovimab. "These promising results demonstrating decreased incidence of RSV disease, including hospitalizations, highlight the potential for clesrovimab to play an important role in helping to alleviate the continued burden of RSV on infants and their families," he stated.

Merck's clesrovimab could potentially rival the treatment Beyfortus, developed by Sanofi and AstraZeneca, which faced a shortage last RSV season due to high demand. Unlike Beyfortus, which requires weight-based dosing, Merck's treatment can be given to infants irrespective of their weight, potentially offering a more convenient dosing option. Other competitors in the field include Pfizer and GSK, which have introduced RSV vaccines administered to pregnant women to confer immunity to their newborns.

With these promising trial results, Merck is on track to potentially revolutionize RSV treatment for infants and significantly mitigate the virus's impact on this vulnerable population.