Pegvaliase therapy for phenylketonuria: Real-world safety, efficacy, and medication access outcomes in a pharmacist-led pegvaliase program

Abstract

Purpose: Given the complexity and close monitoring needs of pegvaliase, we evaluated the real-life clinical outcomes of patients with phenylketonuria (PKU) managed in a pharmacist-led pegvaliase pharmacotherapy program.

Methods: A review of 51 PKU patients initiated on pegvaliase at the PKU clinic of M Health Fairview, Minneapolis, MN, between May 2018 and May 2024 was conducted. Data collected included baseline characteristics, payer authorization outcomes, treatment history, phenylalanine (Phe) levels, adverse events, and management strategies.

Results: At 12-months, 55% of patients achieved Phe goal (360 μmol/L), increasing to 77% at 24 months. Among patients on maintenance doses, 87% achieved ≥20% Phe reduction at 12 months, rising to 93.5% at 24 months. Combination therapy with sapropterin and pegvaliase was associated with faster Phe goal attainment compared with pegvaliase monotherapy (P = .0599). Anaphylaxis occurred in 31% of patients, predominantly during the maintenance phase. All patients successfully initiated therapy without access barriers, although 35% required appeals for insurance approval. Common adverse events included injection site reactions (90%) and arthralgia (69%). Special populations, including 1 adolescent and 2 pregnant women, were safely managed on pegvaliase.

Conclusion: Pegvaliase effectively reduced Phe levels in PKU patients, although it carried significant risks of anaphylaxis and other adverse events. A pharmacist-led program and interdisciplinary collaboration was crucial for prompt access and effective management.

Keywords: Pegvaliase; Pharmacist-led program; Phenylketonuria.