biostudies-literatureChew KWNational Institute of Allergy and Infectious DiseasesNCATS NIH HHSNIAID NIH HHSNational Institutes of HealthNIH HHS131-136https://www.ebi.ac.uk/biostudies/studies/S-EPMC11793053biostudies-literatureUnknown231(1)We explored viral and symptom rebound after coronavirus disease 2019 amubarvimab-romlusevimab monoclonal antibody therapy versus placebo in the randomized ACTIV-2/A5401 trial. Participants underwent nasal severe acute respiratory syndrome coronavirus 2 polymerase chain reaction testing at study days 3, 7, 14, and 28. Viral rebound was defined as RNA ≥3 and ≥0.5 log10 copies/mL increase from day 3 or 7, and symptom rebound as hospitalization or any moderate/severe symptom for ≥2 days after initial symptom improvement. There was no difference in viral rebound (∼5%/arm) (analysis population n = 713) or symptom rebound among participants who initially improved (hazard ratio, 0.95 [95% confidence interval, .52-1.75]; analysis population n = 574); <1% had both viral/symptom rebound.The Journal of infectious diseasesViral and Symptom Rebound Following Anti-Severe Acute Respiratory Syndrome Coronavirus 2 Monoclonal Antibody Therapy in a Randomized Placebo-Controlled Trial.PMC11793053U01 AI068636UM1 AI106701UM1 AI069424UM1 AI068634UM1AI068636UL1 TR001881UM1 AI068636UM1AI068634UM1 AI069419UM1AI106701Kosmyna JJilg NMcGinley BMurtaugh WEvering TEron JJPatel NHughes MSmith DDCurrier JSJennings CSingh UGottesman JHosey LLi JRiviere CBeck JMoser CPerelson AEvering THMargolis DSmith DMEron JFischer WWohl DACurrier JGiganti MDaar ESFletcher CHughes MDDaar EChew KWNewell MSieg SAccelerating COVID-19 Therapeutic Interventions and Vaccines (ACTIV)-2/A5401 Study Team, Study Sites, and InvestigatorsGapara MChew KCorado KWohl DTaiwo BJagannathan PRwakazina ILi JZRitz JJavan ACShahkolahi AColsh KPillay SCardoso SRoa JPedersen SIgnacio RBDragavon JGreenfelder BfalseViral and Symptom Rebound Following Anti-Severe Acute Respiratory Syndrome Coronavirus 2 Monoclonal Antibody Therapy in a Randomized Placebo-Controlled Trial.We explored viral and symptom rebound after coronavirus disease 2019 amubarvimab-romlusevimab monoclonal antibody therapy versus placebo in the randomized ACTIV-2/A5401 trial. Participants underwent nasal severe acute respiratory syndrome coronavirus 2 polymerase chain reaction testing at study days 3, 7, 14, and 28. Viral rebound was defined as RNA ≥3 and ≥0.5 log10 copies/mL increase from day 3 or 7, and symptom rebound as hospitalization or any moderate/severe symptom for ≥2 days after initial symptom improvement. There was no difference in viral rebound (∼5%/arm) (analysis population n = 713) or symptom rebound among participants who initially improved (hazard ratio, 0.95 [95% confidence interval, .52-1.75]; analysis population n = 574); <1% had both viral/symptom rebound.2025-01-01T00:00:00Z2025 Feb2026-06-04T11:03:00.217Z2026-05-08T03:11:06.27ZS-EPMC117930533940006310.1093/infdis/jiae501