Multi-Dose Safety/Pharmacodynamic Study of SEL-212/SEL-037 in Subjects With Symptomatic Gout & Elevated Blood Uric Acid

This is an open label multicenter study to evaluate the safety and tolerability of multiple doses (3 monthly IV infusions) of SEL-212 ( a combination of pegsiticase ( SEL-037, also known as pegadricase) and SVP-rapamycin (SEL-110)) followed by multiple doses (2 monthly IV infusions) of pegsiticase (SEL-037) alone for a total of 5 treatment cycles in participants with symptomatic gout and hyperuricemia. Additional participants will be treated with multiple doses (5 monthly IV infusions) of pegsiticase (SEL-037) alone. Uricase is an enzyme that converts uric acid to the readily soluble allantoin that is then excreted and SEL-110 is designed to prevent unwanted anti-drug-antibodies (ADAs) from forming. All participants will be monitored for safety and tolerability to drug throughout the study on a weekly schedule. Pharmacokinetic and pharmacodynamic parameters will at specific timepoints to monitor for continued efficacy. Pharmacodynamic parameters measured include uric acid levels and levels of ADAs. The study duration per enrolled participant will be approximately 6 months including a 1 month screening period followed by 5 treatment cycles and an end of treatment visit which will occur 30 days after the last IV infusion .