Antibody therapies are being developed to prevent respiratory syncytial virus in babies
The burden of respiratory viral disease in low- and middle-income countries is too big or too small, says Maria Zambon, director of infectious diseases at the UK health security agency
When people began to socialize more often, they bounced back. Canada, Japan and several countries in the European Union reported a sharp rise in RSV cases. The same was probably true in low- and middle-income countries (LMICs) too, where RSV has the biggest affect. It is not known for sure, however, because the systems and infrastructure needed to track the disease in those countries are inadequate, or missing altogether. Maria Zambon, head of respiratory infectious diseases at the UK health security agency in London, says that a lot of deaths due toRSV happen in low and middle-income countries. Most LMICs don’t have a lot of RSV data.
The WHO project focused on the demographic of children under the age of two, because they are disproportionately affected by RSV. Jinal Bhiman, a medical scientist at the National Institute for Communal Diseases in South Africa, says that the age group with the highest number of deaths from RSV is between the ages of 18 and 25.
Rural areas are not adequately represented even in countries where there is some surveillance infrastructure. “Most sentinel surveillance hospitals are in urban areas,” says Eva Leidman, an epidemiologist at the US Centers for Disease Control and Prevention’s National Center for Immunization and Respiratory Diseases in Atlanta, Georgia.
But surveillance is just one part of the puzzle. To understand the affects of this disease in a population, countries need to conduct burden estimation studies. These studies, which track the number of hospitalizations caused by the viruses and follow how many go on to get sick and die, can be expensive. According to Zambon, that will tell them where to use the interventions. It is hard to estimate the disease burden because health-care providers aren’t required to report deaths associated with Rsv.
The cost of long-acting neoniconoclonal antibodies for children’s healthcare: a case study in the Nunavik Arctic
Unless you have ever had cancer or an inflammatory disorder, most likely you haven’t ever been a patient of an antibody drug. Oliver DeLong, a healthy baby from Chicago, Illinois, probably got his first therapy before he was four months old.
Oliver participated in a clinical trial in 2021 that involved a unique kind of antibody treatment, one designed to prevent, rather than treat, disease. When given before the start of theRSV season, nirsevimab can help babies avoid the types of lung infections that often lead to hospitalization.
Researchers at Regeneron, a pharmaceutical company in Tarrytown, New York, learnt this the hard way. Over the course of 20 years, the company’s Suptavumab appeared to be highly potent against a number of RSV strains. Historical records show that the target of the antibody was not different between season to season.
This leaves many people contemplating the role that long-acting antibody drugs will assume amid this new array of prophylactic options. The advantages of these antibodies are not the only challenge due to implementation and parental acceptance.
“Price and ambition will be key,” says Steve Cunningham, a paediatric respiratory-disease specialist at the University of Edinburgh, UK. “There’s going to be a big debate over the next year or two about which is the best coverage option.”
The same price for nirsevimab and other long-actingonoclonal Antibodies will be offered by pharmaceutical companies. In high-income countries, the prices of the antibodies will be between $300 and $500 for infants, which is not much more than the cost of a vaccine forRSV. Prices should be lower in resource-poor settings.
Health authorities in one part of the Canadian Arctic — in the Nunavik region of northern Quebec — launched a pilot programme in 2016 in which they expanded eligibility for palivizumab from high-risk babies to include healthy, full-term newborns. The programme was discontinued in four years because of a lack of health-care resources and a lack of cost-effectiveness during the most severe RSV seasons.
Things shouldn’t be what they are with nirsevimab. The modelling study says nirsevimab is a low-cost option that will streamline the administration process while also being highly cost-effective or cost-saving.
Eliminating the Potential for Resistance in Anti-RSV Antibody Efficacy: A Comparison Between Adimab and RSM01
Maternal vaccinations can help the babies by increasing their immunity and making them less vulnerable to diseases. It would give even more protection if the approaches were doubled. With limited budgets, public health officials may have to decide between giving synthetic anti-RSV antibodies to babies or giving jabs to expectant mothers.
Of course, it doesn’t have to be one or the other. Offering both could achieve maximal population coverage if they were both offered, considering the different health care systems in different countries and the acceptance of medical interventions.
Notably, clesrovimab has several design features that make it distinct from, and complementary to, nirsevimab. One key distinction is its target location on the RSV fusion protein. It was found that the spot on theProteins apex is only present in the pre-activation state and must be changed before it can enter host cells. But, clesrovimab latches on to the protein’s flank, on an area that remains consistent across different conformations of the protein.
The few mutations observed so far have reduced the potency of nirsevimab11. Still, the potential for resistance remains an area of concern — one that requires close monitoring, says Octavio Ramilo, a paediatric infectious-disease researcher at St. Jude Children’s Research Hospital in Memphis, Tennessee. He says we need to watch the changes and see what happens.
The two agents of Adimab, called nirsevimab and the other one, called RSM01, are very similar. Laura Walker, a former head of science at Adimab, said that the antibodies have the same potency in laboratory experiments as the ones they bind to. The differences are not that big, she says. RSM01, however, has an important potential advantage. A non-profit biotechnology arm of the Bill & Melinda Gates Foundation plans to advance the drug and offer it in low- and middle-income countries for as little as manufacturing costs will allow.
The first people to benefit from nirsevimab will be in wealthier parts of the world, most likely children such as Oliver.
RSV in the Age of Convalescence: The Prospects for Survival and Health Care in the Early Stages of Infections and Diseases
We are pleased to acknowledge the financial support of Moderna in producing this Outlook. Nature retains sole responsibility for all editorial content.
Research also suggests that the effects of RSV might linger long after the initial infection has been cleared; studies are beginning to uncover links between RSV infections and respiratory problems in later life, such as wheezing and asthma. Other research is beginning to unpick how other pathogens in a host might collaborate or compete with RSV.
Infections and vulnerable people are being kept out of the hospital, but they present new challenges in the deployment of these strategies.
The burden of respiratory viral disease in low and middle-income countries (LMICs) is too big or too small, said Maria Zambon, director of infectious diseases at the UK health security agency. In high-income countries, the prices of the antibodies will be between $300 and $500 for infants, which is not much more than the cost of a vaccine for RSV.