Wall Street promptly began trying to weigh the compound’s marketplace odds after Merck & Co. Inc. detailed positive data from the phase IIb/III trial known as MK-1654-004 with clesrovimab, an investigational prophylactic monoclonal antibody designed to protect infants from respiratory syncytial virus (RSV) disease during their first RSV season. The results, plus interim findings from the ongoing phase III experiment dubbed MK-1654-007 were offered during IDWeek 2024 in Los Angeles.