RECIPE Randomized Controlled Trial Data Published in Arthritis & Rheumatology Show Higher Response Rates Using KRYSTEXXA® (pegloticase injection) with the Immunomodulator Mycophenolate Mofetil

Horizon Therapeutics plc (Nasdaq: HZNP) announced the publication of data from the first randomized controlled clinical trial (RCT) of KRYSTEXXA (pegloticase injection) concomitantly used with an immunomodulator, mycophenolate mofetil, in Arthritis & Rheumatology [doi.org/10.1002/art.41731].

The Reducing Immunogenicity of Pegloticase (RECIPE) trial demonstrated that 86 percent of patients (19 of 22) receiving co-therapy of KRYSTEXXA with the immunomodulator mycophenolate mofetil achieved serum uric acid (sUA) ≤ 6 mg/dL at 12 weeks, the primary study endpoint, compared to 40 percent of patients (4 of 10) receiving KRYSTEXXA monotherapy. The safety and efficacy of KRYSTEXXA co-prescribed with mycophenolate mofetil has not been established by any health authorities.

“Our focus on urgently reducing the buildup of uric acid crystals and addressing the impact of uncontrolled gout on patients led us to explore how to curtail the development of anti-drug antibodies with pegloticase through the RECIPE trial,” said Puja Khanna, M.D., M.P.H., associate professor and rheumatologist at the University of Michigan, and co-primary investigator for the RECIPE trial. “This trial adds major insight to the evolving body of data – that co-treatment with immunomodulatory medications can mitigate antibody production, and thereby improve the response rates of pegloticase. We believe that this novel approach has the potential of meaningfully improving the patient’s response to urate lowering therapy and long-term outcomes as a result.”

Data from this investigator-initiated Phase 2, double-blind, placebo-controlled proof-of-concept trial led by the University of Alabama at Birmingham and University of Michigan funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) and Horizon illustrate the effect of a concomitant regimen of KRYSTEXXA with mycophenolate mofetil. In the study, 35 adult patients with uncontrolled gout were randomized (3:1) to receive either mycophenolate mofetil or placebo for two weeks prior to starting KRYSTEXXA (12 infusions of 8 mg every two weeks). Thirty-two patients received at least one dose of KRYSTEXXA and were included in the analysis, with three patients discontinuing prior to the first KRYSTEXXA infusion. During the trial, patients continued to receive either mycophenolate mofetil (1g) twice daily or placebo with KRYSTEXXA for 12 weeks. After Week 12, all patients received only KRYSTEXXA 8 mg IV every two weeks for 12 weeks, providing six months of KRYSTEXXA therapy. The primary endpoint was the proportion of patients who reached and maintained response to therapy (defined as sUA levels ≤6 mg/dL at 12 weeks).¹

In total, 86 percent (19 of 22) of patients receiving co-therapy of KRYSTEXXA and mycophenolate mofetil achieved serum uric acid ≤ 6 mg/dL at Week 12 versus 40 percent (4 of 10) of patients in the KRYSTEXXA and placebo arm, with a sustained response at Week 24 in 68 percent (15 of 22) of patients versus 30 percent (3 of 10) of patients, respectively. In the KRYSTEXXA with mycophenolate mofetil arm, no (0 of 22 patients) infusion reactions were reported compared to 30 percent (3 of 10) of patients reporting infusion reactions in the KRYSTEXXA with placebo arm. The most commonly reported adverse events for the KRYSTEXXA with mycophenolate mofetil arm versus the KRYSTEXXA with placebo arm included musculoskeletal (41 percent versus 10 percent), gastrointestinal disorders (18 percent versus 10 percent), respiratory (18 percent versus 0 percent) and infections (9 percent versus 0 percent).¹

“This publication reflects a fundament