ADVERSE DRUG REACTIONS ASSOCIATED WITH THE USE OF RIBAVIRIN IN THE TREATMENT OF SEVERE ACUTE RESPIRATORY SYNDROME (SARS)

Background Health Canada's Special Access Programme (SAP) provided access to nonmarketed formulations of ribavirin (oral and parenteral) to physicians treating patients with probable or suspect SARS from March 14, 2003 to April 26, 2003. Objectives To report on an active surveillance programme employed to monitor adverse drug reactions associated with the use of ribavirin in the treatment of SARS. Methods A series of notices were sent to hospitals requiring the submission of any and all ADRs associated with the use of ribavirin in the treatment of SARS. The ADRs were coded using ADR terminology of the World Health Organization Collaborating Centre for International Drug Monitoring (WHO-ART). Causality assessments were performed using the assessment algorithm of the WHO. Results The SAP authorized access to ribavirin for a total of 246 patients at hospitals in Ontario and British Columbia. A total of 126 ADR reports were received. Hypocalcemia and hypomagnesemia were the most common ADRs reported with 55 and 59 reports respectively. Hemolytic anemia was reported as an ADR in 41 patients and transfusions were reported in 12 cases. Decreased hemoglobin was reported as an ADR in 34 patients and transfusions were reported in 8 cases. Discussion The population of patients treated with ribavirin was known and permitted an accurate understanding of the incidence of ADRs. Health care officials are challenged to develop the capacity to ensure that the use of a drug in a novel disease is carried out in a controlled setting to maximize the integrity of data collection and patient protection.