**Merck Announces Positive Results from Late-Stage Study of RSV Antibody**
*October 2023* — Merck & Co., a global leader in biopharmaceuticals, has announced promising results from a late-stage clinical trial evaluating the efficacy of its investigational monoclonal antibody for the prevention of respiratory syncytial virus (RSV) in infants. The announcement marks a significant milestone in the ongoing battle against RSV, a common but potentially severe respiratory infection that primarily affects young children and older adults.
### **RSV: A Global Health Concern**
RSV is a highly contagious virus that causes infections of the respiratory tract. While most healthy individuals recover from RSV within a week or two, the virus can lead to severe complications in infants, particularly those born prematurely or with underlying health conditions. RSV is also a leading cause of hospitalization in children under the age of five, and it can be life-threatening for older adults and individuals with compromised immune systems.
Each year, RSV is responsible for millions of hospitalizations and thousands of deaths worldwide. Despite its significant health burden, there are currently limited preventive options available, particularly for infants who are at the highest risk of severe disease.
### **Merck’s Investigational RSV Antibody**
Merck’s investigational monoclonal antibody, known as **MK-1654**, is designed to provide passive immunity against RSV by targeting the virus and neutralizing its ability to infect cells. Unlike traditional vaccines, which stimulate the body’s immune system to produce its own antibodies, monoclonal antibodies are laboratory-made proteins that can be administered directly to provide immediate protection.
The late-stage clinical trial, known as **RSV-PROTECT**, was a randomized, double-blind, placebo-controlled study that enrolled over 3,000 infants across multiple countries. The trial aimed to evaluate the safety and efficacy of a single dose of MK-1654 in preventing medically attended RSV-associated lower respiratory tract infections (LRTIs) in infants during their first RSV season.
### **Positive Results from the RSV-PROTECT Study**
According to Merck’s announcement, the RSV-PROTECT study met its primary endpoint, demonstrating a statistically significant reduction in the incidence of medically attended RSV-associated LRTIs in infants who received MK-1654 compared to those who received a placebo. The antibody was well-tolerated, with a safety profile consistent with previous studies.
Key findings from the study include:
– **Efficacy**: Infants who received MK-1654 experienced a significant reduction in the risk of RSV-related hospitalizations and medically attended LRTIs compared to the placebo group.
– **Safety**: The antibody was generally well-tolerated, with no major safety concerns reported. The most common side effects were mild and included injection site reactions and mild fever.
– **Duration of Protection**: A single dose of MK-1654 provided protection throughout the entire RSV season, which typically lasts several months.
These results are particularly encouraging given the limited options currently available for RSV prevention in infants. The only approved preventive treatment for RSV in high-risk infants is palivizumab, another monoclonal antibody that requires monthly injections during the RSV season. In contrast, MK-1654 offers the potential for long-lasting protection with a single dose, making it a more convenient and accessible option for families and healthcare providers.
### **Implications for Public Health**
The positive results from the RSV-PROTECT study represent a major step forward in the development of new preventive strategies for RSV. If approved, MK-1654 could become a valuable tool in reducing the global burden of RSV, particularly in infants who are at the highest risk of severe disease.
Dr. Roy Baynes, Senior Vice President and Head of Global Clinical Development at Merck Research Laboratories, expressed optimism about the potential impact of MK-1654. “These results underscore the potential of MK-1654 to provide meaningful protection against RSV in infants, a population that is particularly vulnerable to severe outcomes from this virus. We are committed to working with regulatory authorities to bring this important innovation to patients as quickly as possible.”
### **Next Steps**
Merck plans to submit the data from the RSV-PROTECT study to regulatory authorities in the coming months, with the goal of securing approval for MK-1654 as a preventive treatment for RSV in infants. If approved, the antibody could be available for use as early as the next RSV season.
In addition to its ongoing efforts in RSV prevention, Merck is also exploring the potential of MK-1654 in other populations at risk for severe RSV disease, including older adults and individuals with compromised immune systems. The company is conducting additional clinical trials to evaluate the safety and efficacy of the antibody in these groups.
### **Conclusion**
Merck’s announcement of positive results from the late-stage study of its RSV antibody represents a significant advancement in the fight against RSV. With the potential to provide long-lasting protection with a single dose, MK-1654 could