Patient reports of the frequency and severity of adverse reactions associated with biological agents prescribed for psoriasis in Brazil

BACKGROUND: The safety of biological agents used to treat psoriasis remains uncertain. OBJECTIVE: The authors determined the frequency and severity of adverse effects associated with use of biologic agents for psoriasis through patient-registered lawsuits to the government of Sao Paulo, Brazil. METHODS: Sources of information included legal records, dispensing pharmacy data and interviews with patients. Research staff conducted telephone interviews with patients who used biologic drugs during 2004 - 2011, inquiring about medication-related adverse drug reactions (ADRs) and serious adverse events (SAEs). RESULTS: Of the 218 patients identified, 15 proved ineligible or refused participation. 203 patients were interviewed, with 111 (54.7%) taking infliximab, 43 (21.2%) efalizumab, 35 (17.2%) etanercept and 14 (6.9%) adalimumab. Of 84 (41.4%) patients who experienced one or more ADR related to biological agents, 57 (67.9%) experienced one or more SAE. The only risk factor associated with ADRs was comorbidity odds ratio = 6.54 (95% confident interval [CI] 3.20 - 13.32), p < 0.0001. CONCLUSION: Biologic agents were associated with high rates of ADRs and SAEs. The data suggests that for patients taking a biologic agent to treat psoriasis and who have one or more comorbidities, warnings of possible adverse events and enhanced surveillance are warranted.