RESPIRATORY syncytial virus (RSV) is a prevalent respiratory virus that normally causes mild, cold-like symptoms. Long Ge, of Lanzhou University, Lanzhou City, China, and colleagues, conducted a systematic review and meta-analysis, which revealed a significant decline in RSV-related infections and hospitalisations in children under 5 years old after the prophylactic use of three monoclonal antibodies (mAbs), namely nirsevimab, palivizumab, and motavizumab. The researchers conducted this study to comprehensively compare “the relative efficacy and safety of different mAbs.”
Ge and their team included 14 randomised, controlled trials involving over 18,042 high-risk children. Compared to the placebo, they reported moderate- to high-certainty evidence showcasing that nirsevimab, palivizumab, and motavizumab were linked with significant decreases in RSV-related infections and hospitalisations per 1,000 participants. Moderate certainty evidence also demonstrated that intensive care unit admissions per 1,000 participants were significantly lower with motavizumab and palivizumab, compared with placebo. The same was observed for supplemental O2 use per 1,000 participants, while nirsevimab was linked with significantly decreased supplemental O2 use per 1,000 participants. No significant differences were observed in all-cause mortality or drug-related adverse events.
The researchers stated, “the World Health Organisation (WHO) published documents in 2021 that already encouraged the development of preventive interventions for RSV. Palivizumab is currently the most widely used prophylaxis for preventing RSV disease in infants.” They added, “although the efficacy of palivizumab has been proved, it is not available in some countries, such as China. Meanwhile, the high price of palivizumab imposes a substantial economic burden on low- and middle-income families. Therefore, new mAbs have been developed, such as nirsevimab, which could protect infants from RSV-related infection and hospitalisation during an entire RSV season with a single dose.”
Ge and colleagues highlighted that some comparison groups could only be examined via indirect comparisons, as they lacked direct evidence. Due to the risk of bias and inaccuracy, some comparisons were ranked as low certainty of evidence because they lacked evidence or a wide credible interval. The researchers stated that these concerns will be addressed in future investigations.