Ixekizumab, a high‐affinity monoclonal antibody, selectively targets interleukin‐17A and has been shown to be efficacious in the treatment of moderate-to-severe psoriasis, according to a recent study. The study aimed to describe the relationship between ixekizumab concentrations and efficacy response (static Physician Global Assessment [sPGA] and the Psoriasis Activity and Severity Index [PASI) scores] after 12 weeks of ixekizumab treatment in psoriasis patients from 3 phase 3 studies. Data from 2,888 patients randomized to receive placebo or 80 mg ixekizumab every 2 weeks or every 4 weeks were analyzed. Researchers found:
- Both dosing regimens were efficacious, with higher rates of response achieved with the higher range of observed ixekizumab concentrations after every‐2‐week dosing.
- Although higher bodyweight, palmoplantar involvement, lower baseline disease state, or high baseline C‐reactive protein were associated with slightly lower response rates, the magnitude of effect of these factors on sPGA response was small, with all subgroups able to achieve high levels of response.
- The higher concentration ranges achieved with 80 mg every 2 weeks vs every 4 weeks were associated with higher response levels.
Chigutsa E, Velez de Mendizabal N, Chua L, et al. Exposure‐response modeling to characterize the relationship between ixekizumab serum drug concentrations and efficacy responses at week 12 in patients with moderate to severe plaque psoriasis. J Clin Pharmacol. 2018;58(11):1489-1500. doi:10.1002/jcph.1268.