Lack of Effect of 12-Week Treatment with Risankizumab on the Pharmacokinetics of Cytochrome P450 Probe Substrates in Patients with Moderate to Severe Chronic Plaque Psoriasis

ObjectiveThe objective of this study was to characterize the effects of risankizumab on the in vivo activity of cytochrome P450 (CYP) 1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A in psoriasis patients using a cocktail approach.MethodsPatients with moderate to severe chronic plaque psoriasis (n=21) received single oral doses of sensitive probe substrates for CYP1A2 (caffeine 100 mg), CYP2C9 (warfarin 10 mg), CYP2C19 (omeprazole 20mg), CYP2D6 (metoprolol 50 mg), and CYP3A (midazolam 2 mg) on day 1, followed by 12 weeks of subcutaneous risankizumab treatment of 150 mg once every 4 weeks from day 8 to day 92, and again the same cocktail of substrates on day 98. Serial blood samples were collected for determination of the CYP probe drugs and metabolites with and without risankizumab. Trough samples were collected for risankizumab.ResultsThe 90% confidence intervals (CIs) for the area under the plasma concentration-time curve (AUC) from time zero to infinity (AUC) ratios for the CYP probe substrates administered with risankizumab versus without risankizumab were within the default 0.8-1.25 equivalence bounds. Similar results were observed for maximum plasma concentration (C-max), except for omeprazole, for which the lower bound of the 90% CI for C-max (0.73) extended slightly below the default equivalence limit. No differences were observed in metabolite-to-parent drug C-max or AUC ratios with risankizumab versus without risankizumab. Risankizumab trough plasma concentrations significantly exceeded those of the phaseIII regimen of risankizumab in psoriasis (150mg subcutaneously at weeks 0 and 4 and every 12weeks thereafter).ConclusionsRisankizumab did not affect the in vivo activity of CYP1A2, CYP2C9, CYP2C19, CYP2D6, or CYP3A enzymes in patients with moderate or severe plaque psoriasis and therefore has no potential for drug interactions through these enzymes.Clinical trial registrationClinicalTrials.gov Identifier: NCT02772601.