OBJECTIVES:  Adverse drug events (ADEs) lead to 700,000 ER visits and are the fourth leading cause of death in the U.S. ADE costs are paramount to understanding total medical cost and differential economic impacts between therapies. This study examined downstream medical costs associated with infections from the use of TNF-alpha inhibitors. The goal was to establish whether ADE cost analytics can be compared with claims databases to model safer and more cost-effective drug decisions. METHODS:  We analyzed ADE and claims data for six TNF-Alpha inhibitors from August 2013 through July 2015. We examined: 1) ADE and outcome-specific medical costs obtained from AHRQ; 2) ADE and outcome data from FAERS; 3) drug usage information from Evaluate Pharma; and 4) claims data from WEA Trust. ICD-9 diagnoses were mapped to each ADE. Focus was limited to EudraVigilance Important Medical Events and “primary suspect” ADE reports. CPT Service Codes were used to establish three cost measurements: ER visits, hospitalizations, and ambulance transportation. Only medical services incurred after a filed pharmacy claim were examined. RESULTS:  Certolizumab and golimumab were associated with a higher incidence of ADEs compared to other TNF-alpha’s (adalimumab, etanercept, and infliximab) in both ADE and claims data. Downstream medical cost per dispense were: $522, $256, and $190 for certolizumab, adalimumab and etanercept, respectively, for ER visits. Hospitalizations costs were $156, $79, and $57 and ambulance transportation were $30, $19, and $19 for certolizumab, adalimumab, and etanercept, respectively. CONCLUSIONS: Given that both ADE and claims data suggested that two TNF-alpha inhibitors were more likely to cause infections and higher medical costs, WEA Trust will be working with providers to modulate TNF-alpha inhibitor prescriptions to lower cost and improve safety. Future work will examine other drug classes regarding the use of ADE analytics as a proxy for drug benefit design.