P150 Benzbromarone treatment in complex gout: experience in University Sussex Hospitals (East)
Authors: Halai Kapil , Jordon Kelsey M 
Published: April 2022

Abstract

Background/Aims
Benzbromarone is a potent uricosuric drug and has been shown to be highly effective and well tolerated in the management of gout including in impaired renal function. It can be combined with xanthine oxidase inhibitors. There have, however, been reports of severe hepatotoxicity with rare reports of death. These concerns resulted in benzbromarone losing its licence in the UK. The risk of serious hepatotoxicity in Europe is approximately 1 in 17000. Although this drug is still used around the world, in the UK it is used infrequently and restricted to specialist prescribing. We have performed a retrospective review of our experience of benzbromarone use in UHS (East).
Our aims were to assess the outcome of benzbromarone in achieving target serum uric acid (SUA) &lt; 0.36 mmol/L in complex gout patients intolerant of or who have contraindications to usual ULTs.

Methods
Retrospective observational review. Data collected from electronic and paper notes from 2008-2020 in patients who commenced benzbromarone by Rheumatology. Patient demographics, co-morbidities, previous medications, reported symptoms, adverse events, blood monitoring (liver function, renal function and SUA), documented prophylaxis and drug adherence were extracted.

Results
54 patients were included in the analysis; five additional patients were excluded due to incomplete data. Mean patient age: 74 years old. Male n = 36 (67%); Female n = 18 (33%). Mean dose of benzbromarone 126mg and median dose 100mg. Previous medication: allopurinol n = 52 (96%), febuxostat n = 16 (30%), sulfinpyrazone n = 2 (4%) patients. Co-morbidities: hypertension n = 41 (76%); hyperlipidaemia n = 15 (28%); ischaemic heart disease/congestive heart failure n = 40 (74%); diabetes n = 18 (33%); obesity= 7 (13%); osteoarthritis n = 44 (81%); renal stones n = 4 (7%). Documented prophylaxis n = 47 (87%). Mean SUA pre benzbromarone treatment with 0.59 mmol/L; 3 months post treatment SUA 0.36 mmol/L and 1 year post treatment SUA 0.34 mmol/L. Achievement of target SUA at 3 months n = 29 (54%) and 1 year n = 24 (44%). 25/54 (46%) patients reported no gout symptoms within the year. 17/54 (31%) patients stopped treatment due to the following adverse events: n = 4 patients transaminitis within the first year of these only two stopped treatment. N = 7 patients stopped due to drug intolerance (six patients gastrointestinal side effect, one patient had rash). N = 3 patients stopped due to reduced renal function. N = 3 patients stopped due to treatment adherence. N = 2 patients died due to natural death unrelated to benzbromarone.

Conclusion
Our study shows that benzbromarone is effective and tolerated in our patient cohort and is a reasonable second- or third-line option. We ensured patients have regular follow up and blood monitoring monthly for the first 3 months and 3 monthly thereafter to ensure safety. This drug has been recommended as an option in the 2017 BSR gout guidelines.

Disclosure
K. Halai: None. K.M. Jordon: Other; unpaid Trustee/Director of the UK Gout Society.