Interleukin-6 receptor inhibition with tocilizumab induces a selective and substantial increase in plasma IP-10 and MIP-1β in non-ST-elevation myocardial infarction.

AIM

To evaluate the effect of interleukin-6 inhibition with tocilizumab on the cytokine network in patients with acute non-ST-elevation myocardial infarction (NSTEMI).

METHODS

117 patients with acute NSTEMI were randomised to an intravenous infusion of 280 mg tocilizumab or placebo prior to coronary angiography. Blood samples were obtained at baseline, at 6 consecutive points in time during hospitalisation, and at follow-up after 3 and 6 months. Cytokines (n = 27) were analysed with a multiplex cytokine assay.

RESULTS

Using a mixed between-within subjects analysis of variance, we observed a significant (p < 0.001) between-group difference in changes for interferon gamma-inducible protein (IP-10) and macrophage inflammatory protein-1β (MIP-1β), due to significant increases in the tocilizumab group during hospitalisation (i.e., IP-10 median change from baseline during hospitalisation (m), placebo: 3 (-60, 68) pg/ml vs tocilizumab: 209 (69, 335) pg/ml; MIP-1β m, placebo: 5 (-2, 12) pg/ml vs tocilizumab: 39 (24, 63) pg/ml). MIP-1β was inversely correlated to troponin T (r = -0.28, p < 0.05) and neutrophils (r = -0.32, p < 0.05) in the tocilizumab group. In contrast, tocilizumab had only modest or no effects on the other examined cytokines.

CONCLUSIONS

Tocilizumab led to a selective and substantial increase in IP-10 and MIP-1β during the acute phase of NSTEMI, with no or only minor effects on the other measured cytokines. ClinicalTrials.gov, NCT01491074.