Adverse Events with D-penicillamine Therapy in Hepatic Wilson's Disease: A Single-Center Retrospective Audit

Abstract

BACKGROUND AND OBJECTIVE: There are limited data on the adverse events of D-penicillamine in Wilson's disease (WD) that can result in dose modification or treatment discontinuation. The objective of this study was to observe the adverse events related to D-penicillamine in patients with hepatic WD.

Methods: A retrospective audit of prospectively registered hepatic WD patients at a tertiary care center between December 2006 and January 2020 was carried out. Demographic variables, laboratory parameters, and details of treatment were noted. Adverse events (AEs) related to D-penicillamine treatment, the timing and management of these AEs were analysed.

Results: The study included 112 patients with hepatic WD on D-penicillamine. D-penicillamine intolerance was seen in 28/112 (25%) over 179 person-years. Of the 28 AEs, severe AEs leading to permanent D-penicillamine discontinuation occurred in 16 (57%) [never reintroduced 12 (43%), discontinued after intolerant to rechallenge, 4 (14%)], temporary cessation followed by reintroduction to initial dose 13 (46%) and continuation with reduced dose in 3 (11%) patients. Overall, most common AEs were hematological [16, 57% (pancytopenia n = 8, bicytopenia n = 5 and hemolytic anemia n = 3)] while renal adverse events (n = 7, 25%) constituted the most common indication for permanent discontinuation. Cytopenias developed beyond 12 months of D-penicillamine initiation whereas hemolytic anemia developed within first 3 months. Following D-penicillamine discontinuation in 25 patients, it was reintroduced to initial dose in 13/25 (52%), switched to trientine due to neurological worsening in 2/25 (8%) and switched to zinc in 10/25 (40%). In patients with reintroduction, gradual dose escalation was tolerated in 9/13 (69%) with a recurrence of AEs leading to permanent discontinuation in 4/13 (31%).

Conclusion: D-penicillamine treatment is associated with significant AEs mainly related to blood, kidney, and skin. Temporary cessation of drug with reintroduction at a lower dose is an effective and safe option.