Treatment of respiratory syncytial virus bronchiolitis and pneumonia in a cotton rat model with systemically administered monoclonal antibody (palivizumab) and glucocorticosteroid

Parenteral treatment of an experimental respiratory syncytial virus (RSV) infection in a cotton rat model with a monoclonal antibody directed against the viral F protein resulted in the clearance of infectious virus within 24 h but had no effect on the pulmonary pathology at 24 h and only a small effect on the pulmonary pathology at 72 h. Treatment with parenteral triamcinolone acetonide dramatically reduced the pathologic lesions of viral bronchiolitis and pneumonia but resulted in the delayed clearance of the virus. The combination of the monoclonal antibody given in a single dose 72 h after infection, combined with 3 daily doses of the corticosteroid starting 72 h after infection, demonstrated both the loss of infectivity and the disappearance of lesions. No rebound of lesions or infectivity was noted, Combined antiviral and anti-inflammatory therapy for RSV disease appears promising.