Oral ribavirin for treatment of respiratory syncitial virus and parainfluenza 3 virus infections post allogeneic haematopoietic stem cell transplantation

The prognosis for patients with respiratory syncytial virus (RSV) or parainfluenza virus type 3 (PIV3) respiratory tract infection post allogeneic haematopoietic progenitor cell transplant (HPCT) is historically poor. The use of oral ribavirin (RBV) has not been widely studied in this patient population. We examined the outcomes of 15 consecutive patients (RSV, n=13 and PIV3, n=2) treated with oral RBV post HPCT. Oral RBV was commenced at a starting dose of 10 mg/kg/day, increasing to a maximum dose of 60 mg/kg/day depending on response and tolerance. At diagnosis, seven patients had upper respiratory tract infection (URTI) and eight had lower respiratory tract infection (LRTI). The starting RBV dose of 10 mg/kg/day did not prevent the progression of URTI to LRTI in any patient. However, with dose escalation, six of the seven patients responded to RBV therapy and survived their infective episode. Of the eight patients presenting with LRTI, six patients survived their infection, again after dose escalation of RBV. There was no dose-limiting toxicity seen in any patient. Our results indicate that oral RBV has clinical efficacy in the treatment of RSV/PIV3 infection post HPCT. However, a starting dose of 10 mg/kg/day appears ineffective; we recommend a starting dose of 20 mg/kg/day in this patient group.