PEGLOTICASE (Krystexxa)

Pegloticase, marketed by Savient Pharmaceuticals as Krystexxa, is a new treatment for chronic gout indicated for those patients refractory to conventional therapy. Pegloticase is a type of enzyme called uricase that has been pegylated (chemical procedure) to have a longer half-life and reduced immunogenicity. This enzyme changes uric acid into a substance called allantoine that can be removed from the body more easily than uric acid in the urine. As a result, KRYSTEXXA lowers uric acid levels, and may keep them low.  Pegloticase requires intravenous administration every 15 days for 6 months. The most common serious side effects are severe allergic reactions, infusion reactions, and flare-ups. It remains unclear for many authors that pegloticase benefits outweigh its risks.

Suggested readings: Arthritis Rheum. 2008 Sep;58 (9): 2882-91; Cochrane Database Systematic Rev.2010 Mar; 17(3):CD008335

FEBUXOSTAT (Uloric)

Febuxostat, marketed by Takeda Pharmaceuticals as Uloric, is a new option to low uric acid in blood. Fuboxostat selectively inhibits xanthine oxidase, which is the enzyme that raises uric acid levels. It emerges as an alternative to allopurinol for those patients who are allergic to allopurinol. It can be taken orally once per day and patients with mild to moderate renal impairment do not have to reduce dose.  Comparative trials with allopurinol have shown greater clinical efficacy of febuxostat in lowering serum uric acid, but not, in the recurrence of gout attacks or decrease the size of tophi.

Suggested readings: N. Engl. J. Med. 353 (23): 2450–61; Lancet. 2011 Jan 8;377(9760):165-77