On Tuesday, Merck & Co Inc (NYSE:MRK) shared topline results from its Phase 2b/3 clinical trial (MK-1654-004) of clesrovimab (MK-1654).

Clesrovimab is the company's investigational prophylactic monoclonal antibody designed to protect infants from respiratory syncytial virus (RSV) disease.

Clesrovimab met its primary safety and efficacy endpoints in the trial, including reducing medically attended lower respiratory infections (MALRI) caused by RSV through Day 150.

Participants were randomized to receive either a single dose of clesrovimab or a placebo.

Detailed study findings will be presented at an upcoming scientific congress, and Merck plans to file these data with global regulatory authorities.

Sanofi SA (NASDAQ:) /AstraZeneca Plc's (NASDAQ:AZN) Beyfortus (nirsevimab) received FDA approval in June 2023 for the prevention of respiratory syncytial virus (RSV) lower respiratory tract disease (LRTD) in newborns and infants.

Sanofi and AstraZeneca revealed data from a real-world trial in May 2023.

The phase 3 HARMONIE study recruited over 8,000 infants 12 months and younger.

Infants who received a single dose of the antibody were 83% less likely to be hospitalized than those who were not inoculated.

Most recently, Japan approved Beyfortus (nirsevimab) for the prophylaxis of lower respiratory tract disease caused by respiratory syncytial virus in all neonates, infants, and children.

Pfizer Inc's (NYSE:PFE) maternal RSV vaccine, Abrysvo, is available as a preventive measure for young infants.

It is advised to be given to women 32 to 36 weeks into a pregnancy to prevent lower respiratory tract infection and severe disease in infants until they are six months old.

Price Action: MRK stock is down 0.77% at $124.72 at the last check on Tuesday.

• Pfizer's RSV Vaccine Abrysvo Clears Concerns Over Preterm Birth Risk, Safety For Pregnant Women, New Study Shows.

Photo Courtesy of Merck