The efficacy and safety of citrate mixture vs sodium bicarbonate on urine alkalization in Chinese primary gout patients with benzbromarone: a prospective, randomized controlled study.

OBJECTIVES: To compare the efficacy and safety of citrate mixture and sodium bicarbonate on urine alkalization in gout patients under benzbromarone treatment. METHODS: A prospective, randomized, parallel controlled trial was conducted among 200 gout patients in the dedicated gout clinic of the Affiliated Hospital of Qingdao University. The participants were randomly divided into two groups (1:1), sodium bicarbonate group (3 g/day) and citrate mixture group (7 g/day). All patients were prescribed with 25 mg/day benzbromarone at initiation and maintained at a dose of 50 mg/day. Clinical and biochemical data were collected at each follow-up time point (baseline, weeks 2, 4, 8 and 12). RESULTS: A total of 182 patients completed the 12-week urine alkalization study. The urine pH value of both groups increased significantly from the baseline to the final follow-up time point (sodium bicarbonate group, 5.50-6.00, P < 0.05; citrate mixture group, 5.53-5.93, P < 0.05). While the comparisons regarding urine pH between treatment groups showed no significant differences for each time point. The estimated glomerular filtration rate (eGFR) dropped significantly after 12 weeks' trial in the sodium bicarbonate group (P < 0.01), while it was comparable between baseline and the last follow-up (P > 0.05) in the citrate mixture group. Results of urine analysis showed that the incident rate of occult blood in the sodium bicarbonate group was higher than that in the citrate mixture group (38 vs 24%, P < 0.05), accompanied by a similar occurrence of kidney stones. After 12-week follow-up, the frequency of twice gout flare in the citrate mixture group was significantly lower than that in sodium bicarbonate group (4 vs 12%, P = 0.037). No treatment-emergent adverse events occurred. CONCLUSION: The efficacy of citrate mixture on urine alkalization is comparable to sodium bicarbonate under benzbromarone treatment without significant adverse events. Citrate mixture is superior to sodium bicarbonate in lowering the incidence of urine occult blood and the frequency of gout attacks. TRIAL REGISTRATION: Registered with ChiCTR (http://www.chictr.org.cn), No. ChiCTR1800018518.

Dapagliflozin Added to Verinurad Plus Febuxostat Further Reduces Serum Uric Acid in Hyperuricemia: The QUARTZ Study.

CONTEXT: Combining a sodium-glucose cotransporter 2 inhibitor with a xanthine oxidase inhibitor (XOI) and a urate transporter 1 (URAT1) inhibitor may enhance serum uric acid (sUA) lowering. However, concerns exist regarding high urinary UA (uUA) excretion rates and subsequent crystallization in renal tubules. OBJECTIVE: To assess whether dapagliflozin added to verinurad, a selective URAT1 inhibitor, and febuxostat, an XOI, increases uUA excretion. DESIGN: Randomized, placebo-controlled, 2-way crossover study (NCT03316131). PATIENTS: Adults with asymptomatic hyperuricemia. INTERVENTIONS: Subjects (N = 36) were randomized to oral once-daily 9 mg verinurad plus 80 mg febuxostat plus 10 mg dapagliflozin for 7 days and 7 days of oral once-daily 9 mg verinurad plus 80 mg febuxostat plus placebo with an intervening 7- to 21-day washout period. MAIN OUTCOME MEASURE: Difference in peak uUA excretion between groups from baseline to day 7. Secondary outcomes included changes in sUA levels and 24-h uUA excretion. RESULTS: Both regimens lowered mean peak uUA excretion (least squares mean changes from baseline: -12.9 mg/h [95% confidence interval (CI): -21.0 to -4.7], dapagliflozin; -13.2 mg/h [95% CI -21.3 to -5.0], placebo). sUA concentrations were lower with dapagliflozin (mean treatment difference -62.3 µmol/L [95% CI -82.8 to -41.8]). Dapagliflozin did not impact verinurad pharmacokinetics, its main metabolites, or febuxostat or fasting plasma glucose levels vs verinurad plus febuxostat. There were no clinically relevant changes in safety parameters. CONCLUSIONS: Dapagliflozin further reduced sUA without influencing uUA excretion, suggesting that its combination with verinurad and febuxostat at the doses tested does not adversely affect kidney function. CLINICAL TRIAL REGISTRATION NUMBER: NCT03316131.

Association between hyperuricemia, gout, urate lowering therapy, and osteoarthritis: A protocol for a systematic review and meta-analysis.

INTRODUCTION: Osteoarthritis (OA), a chronic and degenerative joint disease characterized by articular cartilage degeneration, sclerosis of subchondral bone, and osteophyte formation, is deemed a leading cause of activity limitation and disability among the elderly people. Serum uric acid (UA) is a terminal metabolite of purine compound, while hyperuricemia (HU) and UA crystals are recognized causes of gout. Several studies have investigated the correlations between HU, gout and OA, but the findings are inconclusive. We are also concerned whether the urate lowering therapy (ULT) can become a potential treatment for OA and intend to undertake this meta-analysis to clarify the related hypotheses. METHODS: Systematic literature search will be conducted on PubMed, Embase, and Web of Science to identify relevant studies up to February 2020 using appropriate search strategies. All citations and abstracts retrieved from literature search will be assessed by two reviewers independently. The Newcastle-Ottawa Scale or the Cochrane risk of bias assessment tool will be used as appropriate to assess the quality and the risk of bias of the included studies. The heterogeneity and the publication bias of the studies will be investigated accordingly. RESULTS: We propose to undertake this meta-analysis as a feasible approach to clarify the associations between HU, gout or ULT, and OA. DISCUSSIONS: This meta-analysis will help to strengthen our knowledge of the pathogenesis of OA and promote the development of preventive or treatment strategies. REGISTRATION: PROSPERO registration number CRD42020168769.

2020 American College of Rheumatology Guideline for the Management of Gout.

OBJECTIVE: To provide guidance for the management of gout, including indications for and optimal use of urate-lowering therapy (ULT), treatment of gout flares, and lifestyle and other medication recommendations. METHODS: Fifty-seven population, intervention, comparator, and outcomes questions were developed, followed by a systematic literature review, including network meta-analyses with ratings of the available evidence according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology, and patient input. A group consensus process was used to compose the final recommendations and grade their strength as strong or conditional. RESULTS: Forty-two recommendations (including 16 strong recommendations) were generated. Strong recommendations included initiation of ULT for all patients with tophaceous gout, radiographic damage due to gout, or frequent gout flares; allopurinol as the preferred first-line ULT, including for those with moderate-to-severe chronic kidney disease (CKD; stage >3); using a low starting dose of allopurinol (≤100 mg/day, and lower in CKD) or febuxostat (<40 mg/day); and a treat-to-target management strategy with ULT dose titration guided by serial serum urate (SU) measurements, with an SU target of <6 mg/dl. When initiating ULT, concomitant antiinflammatory prophylaxis therapy for a duration of at least 3-6 months was strongly recommended. For management of gout flares, colchicine, nonsteroidal antiinflammatory drugs, or glucocorticoids (oral, intraarticular, or intramuscular) were strongly recommended. CONCLUSION: Using GRADE methodology and informed by a consensus process based on evidence from the current literature and patient preferences, this guideline provides direction for clinicians and patients making decisions on the management of gout.

A drug-drug interaction study of a novel, selective urate reabsorption inhibitor dotinurad and the non-steroidal anti-inflammatory drug oxaprozin in healthy adult males.

BACKGROUND: Dotinurad is a novel, selective urate reabsorption inhibitor, which reduces serum uric acid levels by inhibiting the urate transporter 1. The results of nonclinical studies indicated the possibility that the concomitant use of the non-steroidal anti-inflammatory drug oxaprozin affects the pharmacokinetics of dotinurad. We evaluated drug-drug interactions with respect to the pharmacokinetics and safety of dotinurad when co-administered with oxaprozin. METHODS: This was an open-label, two-period, add-on study in healthy adult males. For a single dose of 4 mg of dotinurad with and without oxaprozin, we compared its pharmacokinetic parameters and evaluated safety. RESULTS: This study enrolled 12 subjects, 11 of whom completed the study. The geometric mean ratio (90% confidence interval [CI]) of the urinary excretion rate of glucuronate conjugates of dotinurad after co-administration with oxaprozin compared to administration of dotinurad alone was 0.657 (0.624-0.692), while the geometric mean ratios (90% CIs) of the maximum plasma concentration and area under the plasma concentration-time curve from time zero to infinity (AUC0-inf) were 0.982 (0.945-1.021) and 1.165 (1.114-1.219), respectively. During the study, two adverse events occurred after administration of dotinurad alone and one occurred after administration of oxaprozin alone. CONCLUSIONS: In comparison with administration of dotinurad alone, co-administration with oxaprozin was associated with a 34.3% decrease in the urinary excretion rate of the glucuronate conjugates of dotinurad, and a 16.5% increase in AUC0-inf of dotinurad. However, no clinically meaningful drug-drug interactions were observed. Administration of dotinurad alone was similar safety to co-administration with oxaprozin. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03350386.

Dotinurad versus benzbromarone in Japanese hyperuricemic patient with or without gout: a randomized, double-blind, parallel-group, phase 3 study.

BACKGROUND: Dotinurad is a novel selective urate reabsorption inhibitor that reduces serum urate levels in hyperuricemic patients with or without gout by selectively inhibiting urate transporter 1. This study was conducted to compare the efficacy and safety of dotinurad with those of benzbromarone. METHODS: In this 14-week, randomized, multicenter, double-blind, parallel-group, dose escalation, benzbromarone-controlled, phase 3 study, hyperuricemic patients with or without gout were randomized to two groups that received either dotinurad 2 mg or benzbromarone 50 mg. Dotinurad or benzbromarone was administered once a day for 14 weeks. The primary endpoint was the percent change in serum uric acid level from the baseline to the final visit. RESULTS: A total of 201 Japanese hyperuricemic patients with or without gout (dotinurad: 102, benzbromarone: 99) received at least one dose of the study drug. The mean percent change in serum uric acid level from the baseline to the final visit in the dotinurad and benzbromarone groups was 45.9% and 43.8%, respectively. Non-inferiority of dotinurad 2 mg to benzbromarone 50 mg in lowering serum uric acid was verified by the predefined non-inferiority margin (95% CI - 1.27 to 5.37%). The incidence of adverse events and adverse drug reactions was comparable between the two groups. CONCLUSION: Dotinurad 2 mg was verified to have a non-inferior serum uric acid lowering effect compared with benzbromarone 50 mg, in Japanese hyperuricemic patients with or without gout. CLINICALTRIALS. GOV IDENTIFIER: NCT03100318.

Soluble Uric Acid Promotes Atherosclerosis via AMPK (AMP-Activated Protein Kinase)-Mediated Inflammation.

OBJECTIVE: Uric acid is supposed but not yet determined to be associated with atherosclerosis. Uric acid is released from damaged cells to form urate crystal, which is recognized by the immune system to produce IL (interleukin)-1. Danger signals and IL-1 have been shown to play an important role in atherosclerosis. We determined whether the physiological level of soluble uric acid promotes inflammation and develops atherosclerosis. Approach and Results: The secretion of IL-1ß from human peripheral blood mononuclear cells mediated by NLRP3 (NACHT, LRR, and PYD domain-containing protein 3) inflammasome was promoted by physiological levels in serum uric acid. This augmentation of inflammation was mediated by the regulation of the AMPK (AMP-activated protein kinase)-mTOR (mammalian target of rapamycin) mitochondrial reactive oxygen species and HIF-1α (hypoxia-inducible factor-1α) pathway. In both of uricase transgenic and xanthine oxidase inhibitor-treated mice, decreased levels of uric acid resulted in the activation of AMPK and attenuation of the development of atherosclerotic plaques. Further, acute uric acid reduction by the administration of benzbromarone in healthy humans for 2 weeks significantly decreased plasma IL-18-an inflammasome-dependent cytokine. CONCLUSIONS: The data indicate that the development of atherosclerosis and inflammation is promoted by uric acid in vivo. Moreover, the lowering of uric acid levels attenuated inflammation via the activation of the AMPK pathway. This study provides mechanistic evidence of uric acid-lowering therapies for atherosclerosis.

Clinical pharmacological study of dotinurad administered to male and female elderly or young subjects.

BACKGROUND: Dotinurad is a novel selective urate reabsorption inhibitor (SURI) that selectively inhibits the reabsorption of uric acid in renal tubules and promotes the excretion of uric acid into urine. In this study, the effects of age and gender on the pharmacokinetics (PK), pharmacodynamics (PD), and safety of dotinurad were evaluated in healthy subjects. METHODS: An open-label study of a single oral administration of dotinurad 1 mg was conducted in elderly (≥ 65 years) Japanese males and females, and young (20-35 years) males and females (six patients each). RESULTS: Following a single-dose administration of dotinurad, the change in dotinurad plasma concentration showed a similar profile across groups. Regarding the PK parameters, there was no significant difference between elderly and young subjects. On comparing males and females, significant differences were observed in some parameters in elderly subjects. However, these differences in some parameters could not be detected by adjust for body weight. When PD parameters in elderly and young subjects were compared, significant differences were observed in some parameters in male subjects. On comparing males and females, significant differences were observed in some parameters in young subjects; however, the percent change in serum uric acid concentration decreased over time was relatively close for both groups. There were no clinically relevant safety problems. CONCLUSION: Age and gender had no clinically meaningful effect on the PK, PD, and safety of dotinurad. CLINICAL TRIALS: ClinicalTrials.gov identifier: NCT02344875.

Open-label study of long-term administration of dotinurad in Japanese hyperuricemic patients with or without gout.

BACKGROUND: Dotinurad is a novel selective urate reabsorption inhibitor (SURI) which reduces serum uric acid levels by selectively inhibiting urate transporter 1 (URAT1). This study was intended to verify the efficacy and safety of dotinurad following treatment for 34 or 58 weeks in hyperuricemic patients with or without gout. METHODS: This long-term study had an open-label design with dose escalation. The dose of dotinurad started at 0.5 mg/day and was increased progressively to 2 mg/day. If the serum uric acid level of patients did not reach ≤ 6 mg/dL at week 14, the dose was increased to 4 mg/day. The primary endpoint was the percent change in serum uric acid level from the baseline to each visit. RESULTS: At a dose of 2 mg, serum uric acid levels at week 34 and 58 were reduced from the baseline by 46.73% and 47.17%, respectively; at 4 mg, the respective values were 54.92% and 57.35%. At week 34 and 58, the percentages of patients achieving a serum uric acid levels ≤ 6.0 mg/dL with 2-mg dose were 89.11% and 91.30%, respectively; with 4 mg, the respective rates were 97.50% and 100.00%. In addition, the incidences of adverse events and adverse drug reactions were 65.2% and 21.8%, respectively. CONCLUSION: Dotinurad at doses of 2-4-mg sufficiently reduced serum uric acid levels in hyperuricemic patients with or without gout, and its efficacy and safety were verified for long-term administration. ClinicalTrials.gov Identifier: NCT03006445.

Baseline urate level and renal function predict outcomes of urate-lowering therapy using low doses of febuxostat and benzbromarone: a prospective, randomized controlled study in a Chinese primary gout cohort.

BACKGROUND: Low doses of febuxostat or benzbromarone are widely used in Asian countries, but lacking studies to compare the efficacy and safety of the two urate-lowering drugs. METHODS: To compare the efficacy and safety of low-dose febuxostat with low-dose benzbromarone in patients with primary gout, a randomized controlled, open-label trial was performed among male patients with primary gout for urate-lowering therapy (ULT) in a dedicated gout clinic in China. Randomization was carried out by a third-party institution according to random number table. Patients were randomly assigned 1:1 to febuxostat group (Feb group) (20 mg daily) or benzbromarone group (Ben group) (25 mg daily) and treated for 12 weeks. General information and biochemical data were collected at baseline and at every visit monthly. Clinical characteristics before and after the ULT were analyzed in the two groups by SPSS and EmpowerStats software. RESULTS: Two hundred forty patients were enrolled and randomized in the two groups, with 214 patients completing 12 weeks' ULT (105 in the Feb group and 109 in the Ben group). After 12 weeks, substantial percentages of patients in both Feb and Ben group achieved the target serum uric acid (sUA) (< 360 µmol/L) and serum urate levels were reduced significantly for both groups (Feb 39.5% and 156.83 µmol/L vs. Ben 35.7% and 163.99 µmol/L). Multivariate analysis suggests baseline sUA level and renal function were associated with the outcome of the rate of achieving target sUA (RAT). Sub-group analysis suggests low doses of febuxostat and benzbromarone rendered better RAT for patients with sUA < 540 µmol/L and creatinine clearance rate (Ccr) ≤ 110 mL min-1 1.73 m-2 at baseline. The drugs were well tolerated, and the incidence of gout flares in Feb group was similar with that in Ben group (22.85% vs. 33.94%). CONCLUSION: Overall, febuxostat 20 mg daily and benzbromarone 25 mg daily reduced sUA, and gout patients with sUA level < 540 µmol/L or Ccr ≤ 110 mL min-1 1.73 m-2 at baseline had better chance to achieve target uric acid levels. The current study suggests sUA level and renal function are key factors to consider when recommending low doses of febuxostat and benzbromarone to gout patients. TRIAL REGISTRATION: Registered with ChiCTR, No. ChiCTR1800019352 (retrospectively registered).

URC102, a potent and selective inhibitor of hURAT1, reduced serum uric acid in healthy volunteers.

OBJECTIVE: URC102, a novel and potent inhibitor of human uric acid transporter 1 (hURAT1), is currently under clinical development to treat patients with gout. We performed a randomized, double-blind, placebo-controlled, phase I study to evaluate the safety, tolerability, pharmacodynamic, and pharmacokinetic profiles of URC102 after single and multiple oral administration in healthy male subjects. METHODS: Thirty-one Koreans and 23 Caucasians received a single dose of URC102 at 1-30 mg and 1-10 mg, respectively, while 44 Koreans received URC102 once-daily for 7 days at 1-20 mg. We evaluated safety and tolerability throughout the study, and serially determined serum uric acid, the fractional excretion of uric acid and URC102 concentrations. RESULTS: URC102 was well tolerated over the dose range of 1-10 mg after single and multiple administration. URC102 rapidly reduced serum uric acid, which was maintained over the entire treatment period. Furthermore, URC102 increased the area-under-the-effect curve over 168 h for fractional excretion of uric acid in a dose-dependent manner. The maximum plasma concentration and the area under the plasma concentration-time curve of URC102 increased dose-proportionally. The pharmacokinetic and pharmacodynamics characteristics of URC102 were similar in Koreans and Caucasians. CONCLUSION: URC102 was safe and effectively lowered serum uric acid, which should be tested and confirmed in patients with hyperuricaemia and/or gout through further studies. TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT01953497 and NCT02524678.

Efficacy and safety during extended treatment of lesinurad in combination with febuxostat in patients with tophaceous gout: CRYSTAL extension study.

BACKGROUND: In gout, long-term urate-lowering therapy (ULT) promotes dissolution of tissue urate crystal deposits. However, no studies using combined xanthine oxidase inhibition and uricosuric ULT have focused on clinical outcomes or adverse events (AEs) beyond 12 months of therapy. Our objective in the present study was to examine efficacy and long-term safety in patients with tophaceous gout receiving febuxostat plus lesinurad as combination therapy. METHODS: Patients receiving combined lesinurad and febuxostat in the 12-month core CRYSTAL study continued at the same doses in the extension study ("200CONT", "400CONT"), whereas those receiving only febuxostat 80 mg were randomized to lesinurad 200 or 400 mg with febuxostat ("200CROSS", "400CROSS"). The primary endpoint was the proportion of patients experiencing complete resolution (CR) of at least one target tophus by extension month (EM) 12. The key secondary endpoint was mean rate of gout flares requiring treatment from the end of EM 2 to the end of EM 12. Secondary endpoints included reduction in the sum of areas for all target tophi. Safety assessments included AEs and laboratory data for the entire extension study (median length of lesinurad exposure, 800 days). RESULTS: Of 235 patients completing the core study, 196 (83.4%) enrolled in the extension: 200CONT (n = 64), 200CROSS (n = 33), 400CONT (n = 65), and 400CROSS (n = 34). At EM 12, 59.6%, 43.5%, 66.7%, and 50.0% of patients, respectively, had CR of at least one target tophus. The sum of areas for all target tophi was reduced by 76.4%, 58.1%, 77.5%, and 62.8%, respectively. The adjusted mean (SE) rates of gout flares requiring treatment from the end of EM 2 to the end of EM 12 were 0.6 (0.19), 1.3 (0.48), 0.2 (0.08), and 1.9 (0.93), respectively. Target sUA < 5.0 mg/dl was achieved by 77.1%, 79.2%, 88.5%, and 71.4% of patients, respectively. Exposure-adjusted incidence rates of treatment-emergent adverse events (TEAEs) and renal-related TEAEs in the core study were not increased with prolonged lesinurad exposure in the extension study. CONCLUSIONS: Patients receiving lesinurad plus febuxostat therapy for 2 years continued to be at sUA target. Patients exhibited a progressive increase in CR of at least one target tophus, progressive reduction in tophus size, and reduction of gout flares requiring treatment over the second year, with AEs consistent with those observed in the core study. TRIAL REGISTRATION: ClinicalTrials.gov , NCT01510769 . Registered on 13 January 2012.

Efficacy and Safety of Lesinurad in Patients with Hyperuricemia Associated with Gout: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

OBJECTIVE: To evaluate the efficacy and safety of lesinurad for the treatment of hyperuricemia in patients with gout. DESIGN: Systematic review and meta-analysis of randomized controlled trials (RCTs). PATIENTS OR PARTICIPANTS: Five RCTs, which included 1959 patients, compared the efficacy and safety of lesinurad in patients with hyperuricemia associated with gout. MEASUREMENTS AND RESULTS: Relevant studies were identified from PubMed, EMBASE, Cochrane Library databases, and the ClinicalTrials.gov registry. Two reviewers independently assessed the studies. Individual effect sizes were standardized, and a meta-analysis was conducted to calculate the pooled effect size by using a random-effect model. The primary outcomes were the proportion of patients achieving target serum uric acid (sUA) levels by month 6 and the mean sUA levels at month 6 and month 12. Gout-related outcomes were also assessed. The secondary outcome was the number of treatment-emergent adverse events (TEAEs). Compared with xanthine oxidase inhibitor (XOI) monotherapy, lesinurad 200 mg or 400 mg in combination with allopurinol or febuxostat exhibited a higher proportion of patients achieving target sUA levels of < 6.0 mg/dl or < 5.0 mg/dl, respectively, by month 6. Lesinurad-plus-XOI groups also significantly sustained lower mean sUA levels at month 6 and month 12 compared to XOI alone group. In gout-related outcomes, no significant treatment group differences favored lesinurad. The number of TEAEs was comparable between the lesinurad 200 mg-plus-XOI group and the XOI-monotherapy group. Although lesinurad 400 mg monotherapy demonstrated superior efficacy compared with placebo, significantly more TEAEs occurred. CONCLUSIONS: Although the combination of lesinurad 200 mg and XOI is effective and well tolerated for treating patients with gout who have not achieved an adequate response to XOI monotherapy, clinical gout-related outcomes were not improved. Therefore, additional studies investigating the long-term clinical implication of lesinurad are warranted.

Pharmacokinetics, pharmacodynamics, and tolerability of verinurad, a selective uric acid reabsorption inhibitor, in healthy Japanese and non-Asian male subjects.

PURPOSE: Verinurad (RDEA3170) is a selective uric acid reabsorption inhibitor in clinical development for treatment of gout and asymptomatic hyperuricemia. This study evaluated verinurad pharmacokinetics, pharmacodynamics, and tolerability in healthy Japanese and non-Asian adult male subjects. METHODS: This was a Phase I, randomized, single-blind, placebo-controlled study. Panels of 8 Japanese subjects were randomized to receive oral verinurad (2.5-15 mg) or placebo administered as a single dose in a fasted and fed state and as once-daily doses for 7 days in a fed state. Eight non-Asian subjects received verinurad 10 mg as a single dose (fasted and fed) and multiple doses in the fed state. Serial plasma/serum and urine samples were assayed for verinurad and uric acid. Safety was assessed by adverse events and laboratory data. RESULTS: Of 48 randomized subjects, 46 (Japanese, 39; non-Asian, 7) completed the study. Following single or multiple doses in Japanese subjects, maximum plasma concentration (Cmax) and area under the plasma concentration-time curve (AUC) increased in a near dose-proportional manner. Time to Cmax (Tmax) was ~1.25-2.0 hours with fasting. A moderate-fat meal delayed Tmax (range 3.0-5.0 hours) and had a variable effect on AUC (0%-97% increase) and Cmax (0%-26% increase) across the dose groups. Following multiple verinurad 10 mg doses, Cmax and AUC were 38% and 23% higher, respectively, in Japanese vs non-Asian subjects, largely due to body weight differences. Mean reduction of serum urate following multiple verinurad 10 mg doses was 46% and 44% after 24 hours in Japanese and non-Asian subjects, respectively. Verinurad was well tolerated at all doses. CONCLUSION: Verinurad monotherapy lowered serum urate and was well tolerated in both healthy Japanese and non-Asian males, while small differences in plasma pharmacokinetics were observed. These data support further evaluation of once-daily verinurad as a treatment for gout and asymptomatic hyperuricemia.

Verinurad combined with febuxostat in Japanese adults with gout or asymptomatic hyperuricaemia: a phase 2a, open-label study.

Objectives: Verinurad (RDEA3170) is a high-affinity inhibitor of the URAT1 transporter in clinical development for treating gout and asymptomatic hyperuricaemia. The aim of this Phase 2a, randomized, open-label study was to investigate the multiple-dose pharmacodynamics, pharmacokinetics and safety of oral verinurad combined with febuxostat vs febuxostat alone and verinurad alone. Methods: Japanese male subjects aged 21-65 years with gout (n = 37) or asymptomatic hyperuricaemia (n = 35) and serum urate (sUA) ⩾8 mg/dl were randomized to febuxostat (10, 20, 40 mg) in combination with verinurad (2.5-10 mg), verinurad alone (2.5-15 mg), febuxostat alone (10, 20, 40 mg) or benzbromarone alone (50 mg). There were four treatment periods per cohort and each treatment period was 7 days. Study drugs were administered once-daily after breakfast. Plasma, serum and urine samples were measured at pre-set intervals on days -1, 7, 14, 21 and 28. Results: Verinurad combined with febuxostat decreased sUA in dose-dependent manner, providing greater sUA lowering than febuxostat alone at the same dose (P < 0.001). Urinary uric acid excretion rate was increased by verinurad, reduced by febuxostat and comparable to baseline for verinurad combined with febuxostat. Verinurad from 2.5 mg to 15 mg was well tolerated, with no withdrawals due to adverse events. Laboratory assessments showed no clinically meaningful changes during combination treatment. Conclusion: Verinurad combined with febuxostat decreased sUA dose-dependently while maintaining uric acid excretion similar to baseline. All dose combinations of verinurad and febuxostat were generally well tolerated. These data support continued investigation of oral verinurad in patients with gout. Trial registration: ClinicalTrials.gov, https://clinicaltrials.gov, NCT02317861.

Investigational drugs for hyperuricemia, an update on recent developments.

INTRODUCTION: The significant proportion of gout patients not reaching serum urate levels below 6.0 mg/dL and the debated pathogenicity of hyperuricemia (HU) itself motivate investigators to develop new drugs to decrease uricemia. AREAS COVERED: This review discusses the drugs considered to be in active development from pre-clinical to phase III studies. This review covers 11 drugs in development, including a xanthine oxidase inhibitor (topiroxostat), uricosurics (verinurad, arhalofenate, UR-1102, tranilast), dual inhibitors (RLBN1001, KUX-1151), a uricase (pergsiticase), an inhibitor of hypoxanthine production (ulodesine), and drugs with yet-to-explain mechanisms of action (levotofisopam, tuna extracts). EXPERT OPINION: Drugs well advanced in their development - particularly arhalofenate, verinurad and topiroxostat - open the prospect of patient-comorbidity-tailored HU management. Development of novel therapies provides new insight into our understanding of gout and HU, particularly potential pathogenicity. Apart from potency to decrease serum urate levels and good tolerance profiles, novel therapies will need to focus on administration modalities facilitating treatment adherence.

Decreased incidence of diabetes in patients with gout using benzbromarone.

Objective: Insulin resistance is inversely correlated with the clearance rate of uric acid, which may indicate that improvement in the clearance rate of uric acid could reduce insulin resistance. Considering the increased prevalence of diabetes mellitus (DM) in the gout population, this study evaluated the effects of benzbromarone, a uricosuric agent, on the incidence of DM in the gout population. Methods: We used data from the Taiwan National Health Insurance program. The benzbromarone user cohort included 8678 patients; each patient was age- and sex-matched with one benzbromarone non-user who was randomly selected from the gout population. The Cox proportional hazard regression analysis was conducted to estimate the effects of benzbromarone on the incidence of DM in the gout population. Results: The incidence of DM was significantly lower in benzbromarone users than in benzbromarone non-users [adjusted hazard ratio (HR) = 0.86; 95% CI: 0.79, 0.94]. The HR for the incidence of DM was lower in male benzbromarone users (adjusted HR = 0.77; 95% CI: 0.69, 0.86) than in benzbromarone non-users. An analysis of three age groups (<40, 40-59 and ⩾60 years) indicated that the HRs of the age groups of 40-59 years (adjusted HR = 0.86; 95% CI: 0.76, 0.98) and ⩾60 years (adjusted HR = 0.82; 95% CI: 0.71, 0.94) were significantly lower among benzbromarone users than among benzbromarone non-users. Conclusion: In the gout population, the incidence of DM was lower in benzbromarone users than in benzbromarone non-users.

Individualized treatment strategies for hyperuricemia informed by a semi-mechanistic exposure-response model of uric acid dynamics.

To provide insight into pharmacological treatment of hyperuricemia we developed a semi-mechanistic, dynamical model of uric acid (UA) disposition in human. Our model represents the hyperuricemic state in terms of production of UA (rate, PUA), its renal filtration (glomerular filtration rate, GFR) and proximal tubular reabsorption (fractional excretion coefficient, FE). Model parameters were estimated using data from 9 Phase I studies of xanthine oxidase inhibitors (XOI) allopurinol and febuxostat and a novel uricosuric, the selective UA reabsorption inhibitor lesinurad, approved for use in combination with a XOI. The model was qualified for prediction of the effect of patients' GFR and FE on concentration of UA in serum (sUA) and UA excretion in urine and their response to drug treatment, using data from 2 Phase I and 4 Phase III studies of lesinurad. Percent reduction in sUA from baseline by a XOI is predicted to be independent of GFR, FE or PUA. Uricosurics are more effective in underexcreters of UA or patients with normal GFR. Co-administration of a XOI and an uricosuric agent should be considered for patients with high sUA first in the treatment algorithm of gout before uptitration of XOI. The XOI dose in combination with a uricosuric can be reduced compared to XOI alone for the same target sUA to the degree dependent on patient's GFR and FE. This exposure-response model of UA can be used to rationally select the best drug treatment option to lower elevated sUA in gout patients under differing pathophysiological situations.

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.

Lesinurad monotherapy in gout patients intolerant to a xanthine oxidase inhibitor: a 6 month phase 3 clinical trial and extension study.

Objective: To investigate the efficacy and safety of lesinurad, a selective uric acid reabsorption inhibitor, in a 6 month, phase 3 clinical trial and extension study. Methods: Patients with gout who cannot take a xanthine oxidase inhibitor (XOI) and have serum uric acid (sUA) ⩾6.5 mg/dl were randomized to receive oral lesinurad (400 mg daily) or placebo. The primary endpoint was the proportion of patients with sUA <6.0 mg/dl at month 6. Safety assessments included treatment-emergent adverse events (TEAEs) and laboratory data. Patients who completed the study were eligible for an open-label, uncontrolled extension study of lesinurad 400 mg monotherapy. Results: Patients (n = 214) were primarily white males (mean age 54.4 years; gout duration 11.2 years). Significantly more patients achieved the primary endpoint with lesinurad than placebo (29.9 vs 1.9%; P < 0.0001). Overall TEAE rates were higher with lesinurad (77.6 vs 65.4%); renal-related TEAEs (17.8%), renal-related serious TEAEs (4.7%) and serum creatinine elevations (1.5 times baseline, 24.3%) occurred only with lesinurad. A total of 143 patients (65 lesinurad, 78 placebo) enrolled in the extension study. Treatment with lesinurad 400 mg resulted in rapid and sustained sUA lowering that persisted for up to 18 months before the study was terminated prematurely. No new safety findings were observed in the extension. Conclusion: In patients with gout and intolerance/contraindication to XOIs, lesinurad 400 mg monotherapy demonstrated superior sUA lowering compared with placebo, with sustained effects for up to 18 months. Due to a high incidence of serum creatinine elevations and renal-related adverse events, including serious adverse events with lesinurad 400 mg, lesinurad should not be used as monotherapy. Trial registration: ClinicalTrials.gov (http://clinincaltrials.gov), NCT01508702.