Clinical Pharmacokinetics and Pharmacodynamics of Risankizumab in Psoriasis Patients

Risankizumab is a humanized immunoglobulin (Ig) G1 monoclonal antibody developed and approved for the treatment of moderate-to-severe plaque psoriasis at a dose of 150 mg administered subcutaneously at weeks 0 and 4, and every 12 weeks thereafter. Ongoing trials are investigating the use of risankizumab in other inflammatory autoimmune diseases. Risankizumab exhibits linear pharmacokinetics when administered intravenously (0.01 mg/kg–1200 mg) or subcutaneously (0.25 mg/kg–300 mg), with a long terminal half-life of approximately 28 days. Following subcutaneous administration, peak plasma concentration was reached approximately 3–14 days after dosing, with an estimated bioavailability of 89%. Population pharmacokinetic analyses identified bodyweight, high titers of antidrug antibodies occurring in < 2% of evaluated subjects, baseline serum albumin, baseline high-sensitivity C-reactive protein, and baseline serum creatinine to be statistically correlated with risankizumab clearance, but none of them had a clinically meaningful impact on risankizumab efficacy in psoriasis patients following the clinical dosing regimen. Exposure–response analyses in psoriasis patients demonstrated that the maximum efficacy was achieved with the clinically approved regimen and there was no apparent correlation between risankizumab exposure and safety. A dedicated drug interaction cocktail study in patients with psoriasis demonstrated a lack of therapeutic protein–drug interaction potentials for risankizumab and various cytochrome P450 substrates. In this article, we review the clinical pharmacology data available to date for risankizumab, which supported the clinical development program and ultimately regulatory approvals for risankizumab in the treatment of patients with moderate-to-severe plaque psoriasis.