Pharmacokinetic Comparability of Risankizumab Formulations in Prefilled Syringe and Auto-injector for Subcutaneous Injection

Abstract

Purpose: Risankizumab is a humanized immunoglobulin G1 monoclonal antibody that inhibits the p19 subunit of interleukin 23 from interacting with its receptor for the treatment of moderate to severe plaque psoriasis. The aim of this Phase I biopharmaceutics bridging study was to evaluate the pharmacokinetic comparability, immunogenicity, and tolerability of the risankizumab 90 mg/mL prefilled syringe (PFS) and the risankizumab 150 mg/mL PFS and auto-injector (AI) in healthy subjects.

Methods: Healthy subjects received one 150-mg dose of risankizumab in 1 of 3 ways (226 subjects randomized 3:3:1 to 3 treatment arms): 150 mg/mL by PFS × 1 SC injection, 90 mg/mL by PFS × 2 SC injections, or 150 mg/mL by AI × 1 SC injection, and were followed up for 140 days after dosing for the collection of pharmacokinetic, immunogenicity, and tolerability data.

Findings: Risankizumab concentration-time profiles overlapped with comparable pharmacokinetic parameters across all treatment arms, indicating similar pharmacokinetic characteristics. The CIs with both formulations and forms of administration were within the bioequivalence range of 0.80-1.25 across all measures of exposure. The prevalence of treatment-emergent anti-drug antibodies and the percentages of subjects who reported at least 1 treatment-emergent adverse event were comparable across all treatment arms.

Implications: Bioequivalence was established between risankizumab 150 mg/mL PFS and 90 mg/mL PFS, and between 150 mg/mL PFS and AI, along with comparable immunogenicity profiles across all 3 treatment arms. Risankizumab 150 mg SC delivered by PFS or AI was well tolerated, with comparable safety profiles across all treatment arms, and no new safety risks were identified.

Keywords: bioequivalence; monoclonal antibody; pharmacokinetics; psoriasis; risankizumab; tolerability.