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Objectives To determine risks associated with uricosurics in COVID-19 patients. Methods A systematic review and meta-analysis was conducted by systematically searching electronic databases. Key findings The pooled analysis of the included trials revealed that the use of uricosurics was not associated with the risk of mortality (pooled odds ratio [OR] = 1.03, 95% confidence interval [CI]: 0.94–1.12). However, there is a potential mortality benefit associated with the use of ascorbic acid (pooled OR = 0.78, 95% CI: 0.65–0.94). Conclusions The findings confirmed the safety of uricosurics in COVID-19 patients, despite their potential to cause uric acid excretion, which may possess antioxidant properties. [ABSTRACT FROM AUTHOR]

Objectives: The current world witnesses a greatly increased prevalence and incidence of hyperuricemia and gout with unfortunately the comparative efficacy and safety of present available uricosuric agents remaining uncertain. We herein aimed to investigate the most appropriate uricosuric agent for gout or hyperuricemia patients. Method: PubMed, Embase, Cochrane Library databases, and ClinicalTrials.gov from inception to 2 July 2022 were searched to retrieve eligible studies assessing efficacy and safety of uricosuric drugs in hyperuricemia or gout patients. Network meta-analysis was carried out using the Stata 16.0 software. Results: Twelve randomized controlled trials comprising 1851 patients were eventually included. Network meta-analysis showed that dotinurad 4 mg once daily, verinurad, dotinurad 2 mg once daily, dotinurad 1 mg once daily, and benzbromarone were the top 5 effective treatments to achieve target serum uric acid. Furthermore, dotinurad 4 mg once daily was more effective at achieving urate-lowering targets (RR of dotinurad 4 mg once daily vs. probenecid: 1.68, 95% CI [1.13; 2.50]) and safer (RR of probenecid vs. dotinurad 4 mg once daily: 1.77, 95% CI [0.69; 4.56]) than probenecid. Conclusions: This network meta-analysis demonstrated an important absolute benefit of dotinurad 4 mg once daily to achieve target serum uric acid and low risk of adverse events for drug treatment of gout or hyperuricemia patients. Additionally, verinurad might be used as an alternative uricosuric therapeutic option to dotinurad. These findings provided further comprehensive insight into the treatment value of current uricosuric agents for gout or hyperuricemia. Key Points 1. This is the first systematic review and network meta-analysis examining the efficacy and safety of currently available uricosuric agents in gout or hyperuricemia patients. 2. Recommended doses of dotinurad 4mg once daily used for the treatment of gout or hyperuricemia patients can significantly decrease serum uric acid levels. 3. The present findings will provide further comprehensive insight into the treatment value of certain uricosuric agents for gout or hyperuricemia. [ABSTRACT FROM AUTHOR]

Andrographis paniculata (Burm.f.) Nees has been found to have anti-inflammatory and immunostimulatory effects. This study was to investigate antihyperuricemic and anti-inflammatory effects of A. paniculata leaf extracts. Andrographolide, 14-deoxy-11,12-didehydroandrographolide, and neoandrographolide were quantified in 80% ethanol (EtOH80) and water extracts using High Performance Liquid Chromatography (HPLC) analysis. Antihyperuricemic activity was evaluated using a spectrophotometric in vitro inhibitory xanthine oxidase (XO) assay. The most active extract and andrographolide were further investigated in a hyperuricemic rat model induced by potassium oxonate to determine serum uric acid levels, liver XO activity, followed by Western blot analysis for renal urate transporter URAT1, GLUT9, and OAT1 to investigate the excretion of uric acid via kidney. Anti-inflammatory activity was assessed by in vitro interleukin assay for interleukin (IL-1α, IL-1β, IL-6, IL-8), and tumor necrosis factor (TNF-α) in monosodium urate (MSU) crystal-induced human fibroblast-like synoviocyte (HFLS) cells using ELISA-kits, followed by Western blot analysis for the expression of MyD88, NLRP3, NF-κB p65, and caspase-1 proteins to investigate the inflammation pathway. In vivo assay of the most active extract and andrographolide were performed based on the swelling rate and inhibition of pro-inflammatory mediator release from synovial fluid of a rat knee joint induced by MSU crystals. The results showed that the EtOH80 extract had a greater amount of andrographolide (11.34% w/w) than the water extract (1.38% w/w). In the XO inhibitory activity, none of the samples exhibited greater than 50% inhibition. However, in a rat model, EtOH80 extract (200 mg/kg/day) and andrographolide (30 mg/kg/day) decreased serum uric acid levels and reduced liver XO activity, reduced the protein expression levels of URAT1 and GLUT9, and restored the decrease in OAT1 levels. In the in vitro anti-inflammatory study, EtOH80 extract and andrographolide significantly decreased production of IL-1α, IL-1β, IL-6, and TNF-α, as well as inhibited the synthesis of MyD88, NLRP3, NF-κB p65, and caspase-1 in a concentration-dependent manner, almost comparable to dexamethasone. The EtOH80 extract (200 mg/kg/day) and andrographolide (30 mg/kg) significantly decreased swelling rate and IL-1α, IL-1β, IL-6, and TNF-α in the synovial fluid of rat models in a time-dependent manner, comparable to indomethacin (3 mg/kg/day). In conclusion, the findings show that EtOH80 extract has a substantial anti-gout effect by lowering uric acid levels and suppressing pro-inflammatory mediator production due to the andrographolide content, that might be beneficial in the treatment of gouty-inflammation. [ABSTRACT FROM AUTHOR]

Gout is an auto-inflammatory disease driven by urate deposits with a second co-stimulatory factor evoking an (peri)arthritic fulminant inflammation often with a debute at night; inflammatory signals are enhanced via a NLRP3 pathway. In gout patients, urate metabolism has had a positive balance for a time period of weeks to years before the arthritic syndrome or tophaecous disease becomes manifest. This may be due to katabolism or weight loss, enhanced dietary affluence, and overweight resulting in increased serum urate levels. Also, a decreased urate excretion results in proneness to hyperuricaemia and clinical gout. Pharmacotherapeutically, a negative urate balance should be the aim of clinicians and then the rational choice of treatment with uricosurics seems quite logical and promising, but has not had a thorough attention of pharma, researchers nor of clinicians, though most gout patients were and still are low excretors. Here, an overview on the 70-year-old journey mankind has made in a search for uricosurics resulting so far in only 1 registered uricosuric per continent. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Invention of many of the new synthetic drugs is based on the knowledge of traditional system of medicine. Trachyspermum ammi L. (Apiaceae) is traditionally used to treat gout and rheumatism. The study was comprised of in vitro determination of total polyphenolic and flavonoid content, xanthine oxidase inhibition assay and in vivo hypouricemic activity of T. ammi in oxonate induced hyperuricemic rat model. In vivo activity consisted of 11 groups of rats each having 6 animals. All the groups except normal control were treated with potassium oxonate. Allopurinol, T. ammi 250 and 500 mg/kg were administered for one, three and seven days (single dose/day) in different study groups (3x3=9 groups). T. ammi has total phenolic content of 145.17 ± 1.70 gallic acid equivalents/g, and the total flavonoid content of 35 ± 2.20 rutin equivalents/g. T. ammi significantly inhibited xanthine oxidase in vitro (IC50= 68.6±0.2 µg/mL). Oral administration of T. ammi significantly reduced serum and hepatic urate levels in hyperuricemic rats in a time-dependent manner. Furthermore, fractional excretion of uric acid was increased. The results suggested that hypouricemic effects of T. ammi could be explained, at least partly, by inhibiting xanthine oxidase in vitro and due to presence of phenolic and flavonoid contents. [ABSTRACT FROM AUTHOR]

Over the last 70 years, pharmacotherapy in gout with urate-lowering drugs has consisted of four drugs only: In 1952, a mild uricosuric probenecid became available, the xanthine oxidase inhibitor Allopurinol in 1964, and the latter became the most frequently used urate-lowering drug worldwide; in the Eurozone, the uricosuric benzbromarone was welcomed in 1977. Only in 2002, the potent non-purine xanthine oxidase inhibitor febuxostat was introduced. In many countries, uricosurics such as probenecid and benzbromarone have not been available up to now, and these days, the new uricosuric lesinurad is the first uricosuric that may be introduced in these countries, which is the reason for describing the position this novel uricosuric deserves in treating gout. Recent literature will be shortly reviewed, and the current proposed position for lesinurad will be given as an aid for clinicians. [ABSTRACT FROM AUTHOR]

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. Coadministration 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. [ABSTRACT FROM AUTHOR]

Objective. According to recent guidelines, the mainstay of urate-lowering therapies remains xanthine oxidase inhibition. However, some patients with gout show failure to achieve the predefined target of 5-6 mg/dl with xanthine oxidase inhibitors alone, so alternative drugs are needed. The aim of this study was to review studies of novel drugs targeting uric acid transporter 1 (URAT1) and/or other urate transporters for the management of gout. Methods. MeSH terms were used to identify phase 2/3 trials assessing the efficacy of novel uricosurics. A narrative review of novel drugs targeting URAT1 and/or other urate transporters for the management of gout is provided. Results. Lesinurad is a recently approved uricosuric that inhibits URAT1 and the organic ion transporter organic anion transporter 4 (OAT4). Phase 3 trials showed that lesinurad, combined with allopurinol or febuxostat, is a potent urate-lowering therapeutic with an acceptable safety profile. Arhalofenate, another emerging uricosuric, also interacts with URAT1 and organic anion transporter 4. Phase 2 trials suggested that it can both lower serum UA levels and reduce the risk of flares. Conclusions. New drugs inhibiting URAT1 should cover the unmet need for patients with failure to respond or with contraindications to xanthine oxidase inhibitors. [ABSTRACT FROM AUTHOR]

Introduction: The present research work involves the development of a simple, economic, accurate, quick and reproducible UV spectrophotometric method for the estimation of Febuxostat in bulk as well as its pharmaceutical formulation i.e. tablets. Materials and Methods: Phosphate buffer pH 6.8 was used for the preparation of stock solution. Different solutions of drug were prepared by diluting the stock solution with the same buffer. Results: Febuxostat was estimated at UV maxima of 312 nm in pH 6.8 phosphate buffer using UV-Visible double beam spectrophotometer. The drug concentration was found to obey Beer's law over a concentration range of 1-10 μg/ml with line equation y = 0.078x+0.062 and correlation coefficient of 0.999. Results obtained were validated statistically and by recovery study method. Conclusion: The result of analysis was validated according to ICH guidelines and found that the proposed method can be used for quality control of pharmaceutical formulations and routine laboratory analysis. [ABSTRACT FROM AUTHOR]

Lesinurad is an oral inhibitor of the monocarboxylic/urate transporter URAT1 encoded by the SLC22A12 gene. Market authorization was granted in February 2016 in Europe and December 2015 in the USA. As a potentially nephrotoxic uricosuric drug acting on the kidney, nephrologists should become familiar with its indications and safety profile. The approved indication is treatment of gout in combination with a xanthine oxidase (XO) inhibitor in adult patients who have not achieved target serum uric acid levels with an XO inhibitor alone. It is not indicated for asymptomatic hyperuricaemia or for patients with estimated creatinine clearance <45 mL/min. The only authorized daily dose is 200mg and cannot be exceeded because of the nephrotoxicity risk. Nephrotoxicity is thought to be related to uricosuria. At the 200 mg/day dose, serum creatinine more than doubled in 1.8% of lesinurad patients (versus 0% in placebo) and in 11% of these it was not reversible. In addition, it is subject to a risk management plan given the potential association with cardiovascular events. In randomized clinical trials, the association of lesinurad with either allopurinol or febuxostat achieved a greater reduction in serum uric acid (~1 mg/dL lower) than the XO inhibitors alone, and this allowed the serum uric acid target to be met in a higher proportion of patients, which was the primary endpoint. However, no clinical differences were observed in gout flares or tophi, although these were not the primary endpoints. [ABSTRACT FROM AUTHOR]

This position paper aims to clarify the presumed place of febuxostat in the management of gout patients. Since this novel xanthine oxidase inhibitor is now available, an international group of gout experts decided to formulate an international consensus statement. This statement presents the place for this new xanthine oxidase inhibitor in the treatment of gout which may contribute to optimize treatment of gout patients in Europe and worldwide. [ABSTRACT FROM AUTHOR]

Background and Purpose: The xanthine oxidase inhibitors allopurinol and oxypurinol are used to treat hyperuricaemia, whereas loop and thiazide diuretics can cause iatrogenic hyperuricaemia. Some uricosuric drugs and salicylate have a bimodal action on urate renal excretion. The mechanisms of action of these hypo- and hyperuricaemic drugs on the handling of urate in renal tubules have not been fully elucidated. Recently, we identified the multidrug resistance protein (MRP) 4 as a luminal efflux transporter for urate in the proximal tubule.Experimental Approach: Here, we studied the effect of these drugs on [(14)C]urate transport using human embryonic kidney 293 cells overexpressing human MRP4 and in membrane vesicles isolated from these cells.Key Results: Allopurinol stimulated MRP4-mediated cellular urate efflux and allopurinol and oxypurinol both markedly stimulated urate transport by MRP4 in membrane vesicles. Bumetanide and torasemide had no effect, whereas furosemide, chlorothiazide, hydrochlorothiazide, salicylate, benzbromarone and sulfinpyrazone inhibited urate transport, at concentrations ranging from nanomolar up to millimolar. Probenecid stimulated urate transport at 0.1 microM and inhibited transport at higher concentrations.Conclusions and Implications: These data suggest that inhibition of MRP4-mediated urate efflux by furosemide and thiazide diuretics could have an important function in their hyperuricaemic mechanisms. Furthermore, stimulation of MRP4-mediated renal urate efflux could be a new mechanism in the hypouricaemic action of allopurinol and oxypurinol. In conclusion, MRP4 may provide a potential target for drugs affecting urate homoeostasis, which needs to be further evaluated in vivo. [ABSTRACT FROM AUTHOR]

Uric acid (UA) is synthesized mainly in the liver, intestines, and vascular endothelium as the end product of an exogenous purine from food and endogenously from damaged, dying, and dead cells. The kidney plays a dominant role in UA excretion, and the kidney excretes approximately 70% of daily produced UA; the remaining 30% of UA is excreted from the intestine. When UA production exceeds UA excretion, hyperuricemia occurs. Hyperuricemia is significantly associated with the development and severity of the metabolic syndrome. The increased urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) expression, and glycolytic disturbances due to insulin resistance may be associated with the development of hyperuricemia in metabolic syndrome. Hyperuricemia was previously thought to be simply the cause of gout and gouty arthritis. Further, the hyperuricemia observed in patients with renal diseases was considered to be caused by UA underexcretion due to renal failure, and was not considered as an aggressive treatment target. The evidences obtained by basic science suggests a pathogenic role of hyperuricemia in the development of chronic kidney disease (CKD) and cardiovascular diseases (CVD), by inducing inflammation, endothelial dysfunction, proliferation of vascular smooth muscle cells, and activation of the renin-angiotensin system. Further, clinical evidences suggest that hyperuricemia is associated with the development of CVD and CKD. Further, accumulated data suggested that the UA-lowering treatments slower the progression of such diseases. [ABSTRACT FROM AUTHOR]

In rural areas of Latin America, Hyptis infusions are very popular. Hyptis obtusiflora extends from Mexico throughout Central America to Bolivia and Peru. It has added value in Ecuador where it has been used by different ethnic groups. We aimed to learn about the traditional knowledge of ancient Kichwa cultures about this plant, and to contrast this knowledge with the published information organized in occidental databases. We proposed to use traditional knowledge as a source of innovation for social development. Our specific objectives were to catalogue the uses of H. obtusiflora in the community, to prospect on the bibliography on a possible chemical justification for its medicinal use, to propose new products for development, and to give arguments for biodiversity conservation. An ethnobotanical survey was made and a Prisma 2009 Flow Diagram was then followed for scientific validation. We rescued data that are novel contributions for the ethnobotany at the national level. The catalogued main activity of anti-inflammation can be related to the terpene composition and the inhibition of xanthine oxidase. This opens the possibility of researching the extract of this plant as an alternative to allopurinol or uricosuric drugs. This is a concrete example of an argument for biodiversity conservation. [ABSTRACT FROM AUTHOR]