FDA approves RSV shot for infants

After the RSV surge seen last fall, rampant virus case numbers had parents of young infants everywhere understandably worried. But the FDA has now approved a new RSV shot for infants, the monoclonal antibody therapy Beyfortus (nirsevimab), to be offered to babies going through their first or second RSV season. The approval marks one of the first protections for healthy infants against a virus that can be severe or even life-threatening in babies under 12 months.

The vaccine-like therapy is expected to be available in the fall, at the start of RSV season.

The FDA is also reviewing the Pfizer RSV vaccine, RSVpreF, a maternal vaccine to be offered in pregnancy, after an advisory committee recommended its use in May.

Beyfortus is the first product available to prevent severe RSV in infants under 6 months, and works by providing passive immunity against the severe lower respiratory tract infection that RSV can sometimes cause. Strong data support its efficacy and safety of use, and no major safety concerns were seen.

“RSV can cause serious disease in infants and some children and results in a large number of emergency department and physician office visits each year,” said John Farley, M.D., M.P.H., director of the Office of Infectious Diseases in the FDA’s Center for Drug Evaluation and Research. “Today’s approval addresses the great need for products to help reduce the impact of RSV disease on children, families and the health care system.” 

Respiratory syncytial virus, or RSV, is a common childhood virus that nearly every child will have come into contact with by age 2, but it can be especially severe for infants under 12 months and older adults, especially those with pre-existing conditions. The virus is the most common cause of the lung infection bronchiolitis and pneumonia in children under 1 in the US. More than 58,000 children under 5 are hospitalized due to RSV each year, according to the CDC. 

Related: 12 things parents need to know about RSV

The RSV shot will be available for infants this fall

Beyfortus may be recommended for all infants born during or entering their first RSV season, and in children up to 24 months who remain vulnerable to severe RSV disease through their second RSV season.

Monoclonal antibodies work by neutralizing the virus and suppressing viral replication. They can offer babies passive immunity against RSV infection that may to be more effective for longer than giving the mother an RSV vaccine during pregnancy.

Offered as a one-time injection, the treatment was shown in trials to be 76% to 79% effective against medically attended illness, hospitalization and very severe RSV, notes AAP. Side effects including pain at the injection site, rash and fever were uncommon and similar to placebo, and there were no serious adverse reactions reported. 

Related: What you need to know about RSV in infants and kids

RSV vaccines have been in development for decades

The FDA also recently approved two vaccines for adults age 60 and older, though RSV vaccine development had previously been attempted for 50 years.¹Griffin MP, Yuan Y, Takas T, Domachowske JB, Madhi SA, Manzoni P, Simões EA, Esser MT, Khan AA, Dubovsky F, Villafana T. Single-dose nirsevimab for prevention of RSV in preterm infants. New England Journal of Medicine. 2020 Jul 30;383(5):415-25. Until very recently, no RSV shot existed for the population at large. Some pre-term infants who are at higher risk for severe disease from RSV may be eligible for a monthly injection of a monoclonal antibody treatment known as palivizumab during RSV season, but just 2% of babies²Griffin MP, Yuan Y, Takas T, Domachowske JB, Madhi SA, Manzoni P, Simões EA, Esser MT, Khan AA, Dubovsky F, Villafana T. Single-dose nirsevimab for prevention of RSV in preterm infants. New England Journal of Medicine. 2020 Jul 30;383(5):415-25. are able to get those shots.

Related: Flu vaccination rates are the lowest they’ve been in several seasons, CDC warns

For now, prevention is key

In the meantime, RSV prevention is crucial in reducing lung problems later in life, says Octavio Ramilo of Nationwide Children’s Hospital, The Ohio State University College of Medicine, in The Lancet. ³Venkatesan P. Nirsevimab: a promising therapy for RSV. The Lancet Microbe. 2022 May 1;3(5):e335  

If you have children under 12 months during prime RSV season, you may want to take extra precautions. That looks like good hand-washing hygiene and not being in crowded situations with a young baby, he notes. The virus spreads through respiratory droplets from coughing and sneezing, so regularly cleaning shared toys and wiping down surfaces can go a long way in RSV prevention.

An RSV vaccine for adults over age 60, Arexvy, from manufacturer GSK, was recently FDA-approved. In in a study of about 25,000 patients, the vaccine was found to be nearly 83% effective in preventing lower respiratory tract illness in adults 60 and older. Though the vaccine is not yet available, when it is, you may want to ask your child’s grandparents to get the vaccine before meeting your newborn.

A flu shot can also help prevent severe illness that might stem from co-infection—and are available for infants over 6 months. 

Larry Kociolek, the medical director of infection, prevention and control at Ann & Robert H. Lurie Children’s Hospital of Chicago, said to The Wall Street Journal that he strongly encourages parents, particularly those with young children, to have their children immunized with influenza, noting that the past two flu seasons were mild and many kids may not have had sufficient exposure. Protection against flu and other childhood diseases might confer some cross-immunity against RSV. The AAP recommends kids get their flu shot before Halloween each year.

Source(s)

1. Griffin MP, Yuan Y, Takas T, Domachowske JB, Madhi SA, Manzoni P, Simões EA, Esser MT, Khan AA, Dubovsky F, Villafana T. Single-dose nirsevimab for prevention of RSV in preterm infants. New England Journal of Medicine. 2020 Jul 30;383(5):415-25.
2. Griffin MP, Yuan Y, Takas T, Domachowske JB, Madhi SA, Manzoni P, Simões EA, Esser MT, Khan AA, Dubovsky F, Villafana T. Single-dose nirsevimab for prevention of RSV in preterm infants. New England Journal of Medicine. 2020 Jul 30;383(5):415-25.
3. Venkatesan P. Nirsevimab: a promising therapy for RSV. The Lancet Microbe. 2022 May 1;3(5):e335

Additional sources

Rodriguez-Fernandez R, Mejias A, Ramilo O. Monoclonal Antibodies for Prevention of Respiratory Syncytial Virus Infection. Pediatr Infect Dis J. 2021;40(5S):S35-S39. doi:10.1097/INF.0000000000003121 

A version of this story was originally published on Oct. 21, 2022. It has been updated.

Source(s)

• 1
  Griffin MP, Yuan Y, Takas T, Domachowske JB, Madhi SA, Manzoni P, Simões EA, Esser MT, Khan AA, Dubovsky F, Villafana T. Single-dose nirsevimab for prevention of RSV in preterm infants. New England Journal of Medicine. 2020 Jul 30;383(5):415-25.
• 2
  Griffin MP, Yuan Y, Takas T, Domachowske JB, Madhi SA, Manzoni P, Simões EA, Esser MT, Khan AA, Dubovsky F, Villafana T. Single-dose nirsevimab for prevention of RSV in preterm infants. New England Journal of Medicine. 2020 Jul 30;383(5):415-25.
• 3
  Venkatesan P. Nirsevimab: a promising therapy for RSV. The Lancet Microbe. 2022 May 1;3(5):e335