Effect of Leflunomide on Pegloticase Response Rate in Patients with Uncontrolled Gout: A Retrospective Study

Intensive urate-lowering with pegloticase plus methotrexate co-therapy in uncontrolled gout patients with and without chronic kidney disease: A retrospective case series

Chronic kidney disease (CKD) and gout commonly co-occur. Pegloticase lowers serum urate (SU) in uncontrolled gout patients but antidrug antibodies limit urate-lowering response and increase infusion reaction (IR) risk. Methotrexate (MTX) co-administration increases pegloticase response rate and mitigates IR risk but CKD limits MTX use. This pooled case series examined pegloticase + MTX co-therapy in uncontrolled gout patients with and without CKD. Cases of pegloticase + MTX co-therapy in existing datasets were retrospectively examined. Baseline eGFR classified patients as CKD (eGFR < 60 mL/min/1.73 m2) or non-CKD (eGFR ≥ 60 mL/min/1.73 m2). Patient characteristics, treatment parameters, laboratory values, urate-lowering response rate (≥12 pegloticase infusions received and SU < 6 mg/dL just before infusion 12), and AEs were examined. Fifteen CKD (eGFR: 43.2 ± 11.3 mL/min/1.73 m2; SU: 8.6 ± 2.2 mg/dL), 27 non-CKD (eGFR: 82.9 ± 19.0 mL/min/1.73 m2; SU: 9.5 ± 1.7 mg/dL) patients were included. Comorbidity profiles were similar, but CKD patients were older (72.0 ± 9.9 vs 52.3 ± 14.3 years) and more often female (33.3% vs 7.4%). Treatment parameters were similar with 4-week MTX Run-in followed by mean of 14.7 ± 8.1 [CKD] vs 14.1 ± 7.1 [non-CKD] pegloticase infusions. However, CKD patients had lower MTX dose (14.8 ± 5.8 vs 19.3 ± 4.9 mg/week). Urate-lowering response was similar (92% vs 86%). eGFR increased during treatment in 60% of CKD (+11.5 ± 20.9 mL/min/1.73 m2, 87% stable/improved CKD-stage) and 44% of non-CKD (+4.2 ± 15.0 mL/min/1.73 m2) patients. AEs were similar (≥1 AE CKD: 53%, non-CKD: 67%; gout flare most-reported). One case each of pancytopenia and IR (mild) occurred in non-CKD patients. These real-world data show similar pegloticase + MTX efficacy in CKD and non-CKD patients. No new safety signals were identified, with most CKD patients showing renal function stability or improvement during therapy.

Pipeline Therapies for Gout

PURPOSE OF REVIEW

Despite effective available treatments, gout management is often unsuccessful in getting patients to target serum urate goal and in managing flares in the setting of comorbidities. Studies addressing future treatment options for short- and long-term management are reviewed.

RECENT FINDINGS

URAT-1 blocking agents have been helpful but have had limitations related to effects on renal function, lack of efficacy with renal impairment, and potential to increase renal stones. Dotinurad may function in the setting of decreased renal function. Arhalofenate has anti-URAT-1 activity and may also blunt gout flares. A new xanthine oxidase inhibitor (XOI), tigulixostat, is under study. New uricase treatments manufactured in combination with agents that can reduce immunogenicity may make uricase treatment simpler. A unique strategy of inhibiting gut uricase may offer the benefits of avoiding systemic absorption. For gout flares, IL-1β inhibitor studies in progress include different dosing schedules. Dapansutrile, an oral agent under investigation, inhibits activation of the NLRP3 inflammasome and may be an effective anti-inflammatory. New treatments for gout that are under study may work in the setting of comorbidities, simplify management, utilize new mechanisms, or have reduced side effects.

Emerging Urate-Lowering Drugs and Pharmacologic Treatment Strategies for Gout: A Narrative Review

Hyperuricemia with consequent monosodium urate crystal deposition leads to gout, characterized by painful, incapacitating inflammatory arthritis flares that are also associated with increased cardiovascular event and related mortality risk. This narrative review focuses on emerging pharmacologic urate-lowering treatment (ULT) and management strategies in gout. Undertreated, gout can progress to palpable tophi and joint damage. In oral ULT clinical trials, target serum urate of < 6.0 mg/dL can be achieved in ~ 80-90% of subjects, with flare burden reduction by 1-2 years. However, real-world ULT results are far less successful, due to both singular patient nonadherence and prescriber undertreatment, particularly in primary care, where most patients are managed. Multiple dose titrations commonly needed to optimize first-line allopurinol ULT monotherapy, and substantial potential toxicities and other limitations of approved, marketed oral monotherapy ULT drugs, promote hyperuricemia undertreatment. Common gout comorbidities with associated increased mortality (e.g., moderate-severe chronic kidney disease [CKD], type 2 diabetes, hypertension, atherosclerosis, heart failure) heighten ULT treatment complexity and emphasize unmet needs for better and more rapid clinically significant outcomes, including attenuated gout flare burden. The gout drug armamentarium will be expanded by integrating sodium-glucose cotransporter-2 (SGLT2) inhibitors with uricosuric and anti-inflammatory properties as well as clinically indicated antidiabetic, nephroprotective, and/or cardioprotective effects. The broad ULT developmental pipeline is loaded with multiple uricosurics that selectively target uric acid transporter 1 (URAT1). Evolving ULT approaches include administering selected gut anaerobic purine degrading bacteria (PDB), modulating intestinal urate transport, and employing liver-targeted xanthine oxidoreductase mRNA knockdown. Last, emerging measures to decrease the immunogenicity of systemically administered recombinant uricases should simplify treatment regimens and further improve outcomes in managing the most severe gout phenotypes.

Pegloticase in Uncontrolled Gout: The Infusion Nurse Perspective

Infused biologics, such as pegloticase, are a core component of managing uncontrolled gout, which is increasing in prevalence. Pegloticase is often the last line of therapy for patients with uncontrolled gout; therefore, achieving a successful course of treatment is critical. The infusion nurse's role in patient education, serum uric acid monitoring, and patient medication compliance is essential for ensuring patient safety and maximizing the number of patients who benefit from a full treatment course of pegloticase. Infusion nurses are on the front lines with patients and need to be educated on potential negative effects associated with the medications they infuse, such as infusion reactions, as well as risk management methods like patient screening and monitoring. Further, patient education provided by the infusion nurse plays a large role in empowering the patient to become their own advocate during pegloticase treatment. This educational overview includes a model patient case for pegloticase monotherapy, as well as one for pegloticase with immunomodulation and a step-by-step checklist for infusion nurses to refer to throughout the pegloticase infusion process. A video abstract is available for this article at http://links.lww.com/JIN/A105.

Uric acid en route to gout

Gout and hyperuricemia (HU) have generated immense attention due to increased prevalence. Gout is a multifactorial metabolic and inflammatory disease that occurs when increased uric acid (UA) induce HU resulting in monosodium urate (MSU) crystal deposition in joints. However, gout pathogenesis does not always involve these events and HU does not always cause a gout flare. Treatment with UA-lowering therapeutics may not prevent or reduce the incidence of gout flare or gout-associated comorbidities. UA exhibits both pro- and anti-inflammation functions in gout pathogenesis. HU and gout share mechanistic and metabolic connections at a systematic level, as shown by studies on associated comorbidities. Recent studies on the interplay between UA, HU, MSU and gout as well as the development of HU and gout in association with metabolic syndromes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular, renal and cerebrovascular diseases are discussed. This review examines current and potential therapeutic regimens and illuminates the journey from disrupted UA to gout.

A Randomized, Placebo-Controlled Study of Methotrexate to Increase Response Rates in Patients with Uncontrolled Gout Receiving Pegloticase: Primary Efficacy and Safety Findings

OBJECTIVE

To assess efficacy, safety, pharmacokinetics, and immunogenicity of pegloticase plus methotrexate (MTX) versus pegloticase plus placebo cotreatment for uncontrolled gout in a randomized, placebo-controlled, double-blind trial.

METHODS

This study included adults with uncontrolled gout, defined as serum urate ≥7 mg/dl, oral urate-lowering therapy failure or intolerance, and presence of ongoing gout symptoms including ≥1 tophus, ≥2 flares in the past 12 months, or gouty arthritis. Key exclusion criteria included MTX contraindication, current immunosuppressant use, G6PDH deficiency, and estimated glomerular filtration rate <40 ml/minute/1.73 m² . Patients were randomized 2:1 to 52 weeks of pegloticase (8 mg biweekly) with either oral MTX (15 mg/week) or placebo. The primary end point was the proportion of treatment responders during month 6 (defined as serum urate <6 mg/dl for ≥80% of visits during weeks 20-24). Efficacy was evaluated in all randomized patients (intent-to-treat population), and safety was evaluated in all patients receiving ≥1 blinded MTX or placebo dose.

RESULTS

A total of 152 patients were randomized, 100 to receive pegloticase plus MTX, 52 to receive pegloticase plus placebo. Significantly higher treatment response occurred during month 6 in the MTX group versus the placebo group (71.0% [71 of 100 patients] versus 38.5% [20 of 52 patients], respectively; between-group difference 32.3% [95% confidence interval 16.3%, 48.3%]) (P < 0.0001 for between-group difference). During the first 6 months of pegloticase plus MTX or pegloticase plus placebo treatment, 78 (81.3%) of 96 MTX patients versus 47 (95.9%) of 49 placebo patients experienced ≥1 adverse event (AE), most commonly gout flare (64 [66.7%] of 96 MTX patients and 34 [69.4%] of 49 placebo patients). Reports of AEs and serious AEs were comparable between groups, but the infusion reaction rate was considerably lower with MTX cotherapy (4.2% [4 of 96 MTX patients, including 1 patient who had anaphylaxis]) than with placebo cotherapy (30.6% [15 of 49 placebo patients, 0 who had anaphylaxis]) (P < 0.001). Antidrug antibody positivity was also lower in the MTX group.

CONCLUSION

MTX cotherapy markedly increased pegloticase response rate over placebo (71.0% versus 38.5%) during month 6 with no new safety signals. These findings verify higher treatment response rate, lower infusion reaction incidence, and lower immunogenicity when pegloticase is coadministered with MTX.

Community Practice Experiences with a Variety of Immunomodulatory Agents Co-Administered with Pegloticase for the Treatment of Uncontrolled Gout

Objective

Patients with uncontrolled/refractory gout have heavy disease burden, but few treatment options. Pegloticase lowers serum urate (SU), but anti-drug antibodies can limit treatment efficacy. Evidence supports immunomodulator-pegloticase co-administration to increase sustained urate-lowering rates, but published cases are limited. This study investigated experience with pegloticase-immunomodulation co-therapy at two community rheumatology practices.

Methods

Patients initiating pegloticase with immunomodulation in 2017 or later were included. Patient/treatment characteristics and proportion of responders (≥ 12 pegloticase infusions, SU < 6 mg/dl at infusion-12) were examined. Patients on therapy at data collection with < 12 infusions were excluded from response analyses. eGFR before and after therapy was examined.

Results

Thirty-four patients (79% male, 62.4 ± 16.3 years) with uncontrolled gout (SU = 9.1 ± 2.0 mg/dl, 91% tophaceous) were included. Most-reported comorbidities were hypertension (76%), obesity (71%), osteoarthritis (68%), and CKD (47%). Pre-therapy eGFR was 65.4 ± 25.2 ml/min/1.73 m² (41% eGFR < 60 ml/min/1.73 m²). All patients initiated immunomodulation before (5.3 ± 3.0 weeks, n = 32) or at (n = 2) first pegloticase infusion. Subcutaneous methotrexate (15.4 ± 4.9 mg/week, n = 20), oral methotrexate (15.3 ± 3.6 mg/week, n = 9), mycophenolate mofetil (1000 mg/day, n = 3), and azathioprine (100 mg/day, n = 2) were administered. Patients received 14.6 ± 7.1 infusions over 28.5 ± 14.9 weeks. Overall response rate was 89%, ranging among immunomodulators (subcutaneous methotrexate: 93%, oral methotrexate: 89%, mycophenolate mofetil: 100%, azathioprine: 50%). On average, eGFR increased during therapy (+ 10.3 ± 16.9 ml/min/1.73 m²), with CKD stability/improvement in 85%. Nineteen patients (56%) experienced gout flares. No infusion reactions or infections were noted. No new safety concerns were identified.

Conclusions

These real-world findings provide further support for increased pegloticase response rates when co-treatment with immunomodulating therapy is used.

Patients with gout that does not respond to oral urate-lowering therapies have heavy disease burden and few treatment options. Pegloticase lowers serum urate levels (SU) and resolves tophi, but anti-drug antibodies can limit urate-lowering efficacy duration. Evidence increasingly supports co-administering an immunomodulator with pegloticase to increase the proportion of patients with sustained urate-lowering response. However, there are few published cases from real-world clinical practice. This study examined treatment with pegloticase + immunomodulation at two community rheumatology practices. Patients who began treatment with pegloticase and an immunomodulator in 2017 or later were included. The proportion of patients with sustained urate-lowering response (≥ 12 infusions received, SU < 6 mg/dl at infusion 12) was investigated. Renal function before and after therapy was also examined. Thirty-four patients were included. Before treatment, SU averaged 9.1 mg/dl and most-reported comorbidities were hypertension (76%), obesity (71%), osteoarthritis (68%), and chronic kidney disease (47%). All patients began using an immunomodulator before or at first pegloticase infusion (subcutaneous methotrexate [20 patients], oral methotrexate [9 patients], mycophenolate mofetil [3 patients], and azathioprine [2 patients]). On average, 14.6 infusions were administered over 28.5 weeks and overall response rate was 89%. Response rate varied among different immunomodulators: subcutaneous methotrexate: 93%, oral methotrexate: 89%, mycophenolate mofetil: 100%, azathioprine: 50%. On average, kidney function improved, with chronic kidney disease stage stability/improvement in 85% of patients. Nineteen patients (56%) experienced gout flares. No infusion reactions or infections were noted and no new safety concerns were identified. These real-world findings provide further support for administering immunomodulation as co-therapy to pegloticase.