Acute myocardial infarction (MI) occurs when blood supply falls below critical levels and normal cellular maintenance mechanisms fail. Interleukin-6 (IL-6) is a proinflammatory cytokine released in MI and associated with poor clinical outcomes. Tocilizumab (TCZ) is a humanized monoclonal antibody against the IL-6 receptor. In a randomized, double-blinded, placebo controlled trial we assigned subjects admitted with MI a single TCZ dose of 162 mg subcutaneously vs. placebo in addition to standard of care medications and interventions. Primary outcome was a change in major adverse cardiac events (MACE) 30 days after enrollment. Secondary outcomes assessed changes in CRP 30 days after enrollment, changes in QT/QTc, and monitoring for trends in adverse events. Futility analysis was performed as subject enrollment slowed and no trends were noted in either the primary or secondary outcomes. Twenty-eight subjects were enrolled; 12 to TCZ and 16 to placebo. No statistically significant differences were noted between study arms regarding demographics, comorbidities, or medical/interventional therapies received. No statistically significant differences in MACE were observed. CRP increased after administration of TCZ but this was not statistically significant. No adverse events or safety signals were observed. Though futility analysis suggested that the primary outcome was not likely achievable as our recruitment slowed, we did not observe any adverse events or safety trends. Building on this information, future studies should be conducted to assess a true benefit from TCZ as adjunct therapy for MI. The work reported herein was performed under United States Air Force Surgeon General approved Clinical Investigation FKE20140029 and has been registered at ClinicalTrials.gov under identifier NCT02419937.
Keywords: Myocardial Infarction; Rheumatoid Arthritis; Tocilizumab.