Hyperuricemia research progress in model construction and traditional Chinese medicine interventions

Hyperuricemia (HUA), a severe metabolic disease derived from purine metabolism disorder, will lead to abnormally increased serum uric acid (SUA) levels in the body. Studies have shown that HUA is highly related to gout, hypertension, diabetes, coronary heart disease, chronic kidney diseases, and so on. Traditional Chinese medicine (TCM) shows excellent results in treating HUA because of its unique advantages of multi-metabolites and multi-targets. This article reports on the use of TCM components for uric acid (UA)-lowering activity with excellent efficacy and low side effects based on established HUA models. This work summarizes the advantages and limitations of various HUA disease models for efficacy evaluation. Applications of TCM in HUA treatment have also been discussed in detail. This paper reveals recent research progress on HUA in constructing evaluation models and systematic TCM interventions. It will provide a scientific reference for establishing the HUA model and suggest future TCM-related HUA studies.

Advances in pharmacotherapies for hyperuricemia

INTRODUCTION

Hyperuricemia is an overlooked cardiovascular and renal risk factor. Epidemiological and genetic studies have shown an independent role of uric acid in the risk of coronary artery disease, heart failure, chronic kidney disease, and cardiovascular mortality. Treatment options include xanthine oxidase inhibitors, uricosuric medications, and the recombinant uricases. Whether to treat asymptomatic hyperuricemia, and to which target, remains debated. However, the results of recent trials and meta-analysis seem to support this therapeutic strategy.

AREAS COVERED

In the present review, we summarized current therapeutic indications and options for the treatment of symptomatic and asymptomatic hyperuricemia. Furthermore, we searched the recent literature (last 5 years: 2018 to 2022) to report the results of randomized controlled trials and meta-analysis on cardiovascular and nephroprotective effects of hypouricemic agents.

EXPERT OPINION

Future large well-designed clinical trials on the role of hypouricemic agents in nephroprotection and cardiovascular prevention and treatment are warranted and may extend their indications and use, with a direct impact on morbidity and mortality. Differentiating between hyperproducing and hypoexcreting phenotypes may help designing future trials improving the consistency of results. Finally, medications with cardio and nephroprotective properties have shown to reduce serum uric acid levels and may be used in patients with hyperuricemia and other cardiovascular complications.

Effect of Intensive Urate Lowering With Combined Verinurad and Febuxostat on Albuminuria in Patients With Type 2 Diabetes: A Randomized Trial

RATIONALE & OBJECTIVE

Hyperuricemia has been implicated in the development and progression of chronic kidney disease. Verinurad is a novel, potent, specific urate reabsorption inhibitor. We evaluated the effects on albuminuria of intensive urate-lowering therapy with verinurad combined with the xanthine oxidase inhibitor febuxostat in patients with hyperuricemia and type 2 diabetes mellitus (T2DM).

STUDY DESIGN

Phase 2, multicenter, prospective, randomized, double-blind, parallel-group, placebo-controlled trial.

SETTING & PARTICIPANTS

Patients 18 years or older with hyperuricemia, albuminuria, and T2DM.

INTERVENTION

Patients randomly assigned 1:1 to verinurad (9mg) plus febuxostat (80mg) or matched placebo once daily for 24 weeks.

OUTCOMES

The primary end point was change in urinary albumin-creatinine ratio (UACR) from baseline after 12 weeks' treatment. Secondary end points included safety and tolerability and effect on glomerular filtration.

RESULTS

60 patients were enrolled (n=32, verinurad and febuxostat; n=28, placebo). UACRs after treatment with verinurad plus febuxostat were lower than after placebo at 1, 12, and 24 weeks: -38.6% (90% CI, -60.9% to-3.6%), -39.4% (90% CI, -61.8% to-3.8%), and-49.3% (90% CI, -68.2% to-19.0%), respectively. Serum urate levels after treatment with verinurad plus febuxostat were 59.6% and 63.7% lower than after placebo at 12 and 24 weeks, respectively. No clinically meaningful changes were observed in estimated glomerular filtration rate or serum creatinine or serum cystatin C concentrations. Verinurad plus febuxostat was well tolerated.

LIMITATIONS

Sample size and study duration were insufficient to evaluate definitive effects of verinurad plus febuxostat on UACR and glomerular filtration. Generalizability was limited by exclusion of patients with stages 4 and 5 chronic kidney disease.

CONCLUSIONS

Verinurad plus febuxostat reduced albuminuria and lowered serum urate concentrations in patients with T2DM, albuminuria, and hyperuricemia. Definitive assessment of their combined impact on preservation of kidney function awaits larger clinical studies.

FUNDING

This study was supported by AstraZeneca.

TRIAL REGISTRATION

Registered at ClinicalTrials.gov with study number NCT03118739.

Efficacy and safety of lesinurad for the treatment of hyperuricemia in gout

The aim of this review is to present current evidence about the efficacy and safety of lesinurad in combination with xanthine oxidase inhibitors (XOIs) in the treatment of hyperuricemia in patients with gout. Gout is the most common inflammatory form of arthritis. It is caused by an elevated concentration of serum uric acid (UA) that leads to the formation of monosodium urate crystals in joints and different tissues. The goal of therapy is to maintain serum UA levels at <6 mg/dL (0.36 mmol/L), to prevent the formation and deposition of monosodium urate crystals, and to dissolve existing crystals. Lesinurad, a new uricosuric, increases renal urate excretion by selectively inhibiting the renal uric acid transporter 1 (URAT1). Lesinurad is indicated in adults, in combination with a XOI, for the adjunctive treatment of hyperuricemia in patients with gout (with or without tophi) who have not achieved target serum UA levels with an adequate dose of a XOI alone. With the combination strategy, serum UA targets could be reached with the consequence of inhibiting formation of new crystals and promoting dissolution of existing crystals and, therefore, inducing improvement of outcomes such as flares and tophi. The approval of lesinurad was based on data from three pivotal phase III studies (CLEAR 1, CLEAR 2, and CRYSTAL). These clinical studies assessed lesinurad 200 and 400 mg doses. As only lesinurad 200 mg/day dose was finally approved and commercialized, it will be the focus of this paper. In the pivotal clinical trials, the target serum UA level was achieved by significantly more patients in lesinurad 200 mg plus allopurinol group (CLEAR 1 and CLEAR 2 trials) or lesinurad 200 mg plus febuxostat group (CRYSTAL study) compared with patients who received either XOI alone. In these trials, the safety profile of lesinurad 200 mg plus a XOI was comparable to allopurinol or febuxostat alone. Lesinurad, in combination with a XOI, is an effective and safe treatment that covers unmet needs in adults with gout who have not achieved target serum UA levels with a XOI alone.

Guideline development for the management of gout: role of combination therapy with a focus on lesinurad

The aim of this review was to summarize the evidence for combination therapy to achieve serum urate (SUA) target levels in gout. Within this overarching aim, a second aim was to evaluate the evidence for a new uricosuric agent lesinurad, which inhibits urate transport in the kidney. In summary, this review indicates that there are a number of ways to approach patients who do not achieve a target serum urate with allopurinol (APL) monotherapy. These include higher doses of APL up to 600–800 mg/d, switching to febuxostat, or adding in a uricosuric. For the latter option, controlled supporting evidence is available for benzbromarone, probenecid, and lesinurad. All options appear similar in terms of success rates, so the choice of option comes down to physician and patient choice, cost, experience, and strength of the evidence base. Increasing the dose of APL is the cheapest option, while febuxostat is consistently superior to standard doses of APL. The strongest evidence for the uricosuric option is available for lesinurad as trials of other agents are either nonexistent or based on small single-centre trials. It is suggested that guidelines should be expanded to consider all of these evidence-based options in the not-uncommon occurrence of APL inadequate response.

Pharmacokinetics, pharmacodynamics, and safety of lesinurad, a selective uric acid reabsorption inhibitor, in healthy adult males

Lesinurad is a selective uric acid reabsorption inhibitor under investigation for the treatment of gout. Single and multiple ascending dose studies were conducted to evaluate pharmacokinetics, pharmacodynamics, and safety of lesinurad in healthy males. Lesinurad was administered as an oral solution between 5 mg and 600 mg (single ascending dose; N=34) and as an oral solution or immediate-release capsules once daily (qday) between 100 mg and 400 mg for 10 days under fasted or fed condition (multiple ascending dose; N=32). Following single doses of lesinurad solution, absorption was rapid and exposure (maximum observed plasma concentration and area under the plasma concentration–time curve) increased in a dose-proportional manner. Following multiple qday doses, there was no apparent accumulation of lesinurad. Urinary excretion of unchanged lesinurad was generally between 30% and 40% of dose. Increases in urinary excretion of uric acid and reductions in serum uric acid correlated with dose. Following 400 mg qday dosing, serum uric acid reduction was 35% at 24 hours post-dose, supporting qday dosing. A relative bioavailability study in healthy males (N=8) indicated a nearly identical pharmacokinetic profile following dosing of tablets or capsules. Lesinurad was generally safe and well tolerated.