Selective Uric Acid Reabsorption Inhibitor Research Articles

Safety and Efficacy of Dotinurad on Uric Acid in Patients With Chronic Kidney Disease With Estimated Glomerular Filtration Rate Below 25 mL/Min/1.73 m².

Introduction Dotinurad is being developed as a selective uric acid reabsorption inhibitor. However, its effect on lowering serum uric acid (UA) levels in chronic kidney disease (CKD) patients with severe renal dysfunction is unknown. Therefore, the purpose of this study was to determine the effect of dotinurad on renal function in CKD patients with an estimated glomerular filtration rate (eGFR) below 25 mL/min/1.73 m2. Methods Seven patients with CKD who received dotinurad 0.5 mg to 4 mg per day were studied retrospectively. Changes in UA, eGFR, and urine protein-to-creatinine ratio (UPCR) were analyzed. The observation period was 10.9±2.1 months. Results Serum UA levels were decreased and maintained with dotinurad administration. Nevertheless, there were no improvements noted in renal function. Additionally, no serious adverse effects were identified in any of the patients throughout the observation period. Conclusion Although the sample size in this study was small, our findings demonstrate the efficacy of dotinurad in individuals with advanced CKD who have an eGFR lower than 25 mL/min/1.73 m2.

Spectrophotometric quantitative analysis of lesinurad using extractive acid dye reaction based on greener selective computational approach

Computational studies introduce an integral approach for finding greener methods through testing solvents for reactions and extractions. Lesinurad is a novel selective uric acid reabsorption inhibitor prescribed for the treatment of chronic gout. Computational calculations were achieved to choose the best acid dye used for sensitive visible spectrophotometric determination of lesinurad. The calculations were performed using Gaussian 03 software based on density functional theory method with B3LYP/6-31G(d) basis set. The obtained results revealed that bromophenol blue was preferred for lesinurad than other acid dyes based on the higher calculated interaction energy. The described method was based on the reaction of lesinurad with the theoretically selected acid dye bromophenol blue to form a yellow ion-pair complex. The absorption spectra showed maximum sharp peaks at 418 nm. Different factors affecting the reaction were optimized. Beer's law was demonstrated over the concentration range of 2–12 μg/mL lesinurad. The described reaction was utilized for the spectrophotometric determination of lesinurad in pure form and in the pharmaceutical preparation. The greenness of the described method was assessed using four different tools namely, the national environmental method index, the analytical eco-scale, the green analytical procedure index and the novel analytical greenness metric. The proposed method seemed to be superior to the reported HPLC method with respect to the metrics of the greenness characters.

The Effects of Special Patient Population Plasma on Pharmacokinetic Quantifications Using LC-MS/MS.

Clinical development of lesinurad, a selective uric acid reabsorption inhibitor, required analysis of lesinurad in plasma from special patient populations. EMA and FDA bioanalytical method validation guidance have recommended studying matrix effects on quantitation if samples from special patient populations are to be analyzed. In addition to lesinurad (plasma protein binding 98.2%), the matrix effects from special population plasma on the quantitation of verapamil (PPB 89.6%), allopurinol and oxypurinol (PPB negligible) were also investigated. The plasma from special population patients had no matrix effects on the three quantification methods with stable isotope labeled internal standard, protein precipitation extraction, and LC-MS/MS detection. The validated lesinurad plasma quantification method was successfully applied for the pharmacokinetic evaluations to support the clinical studies in renal impaired patients. Special population plasma did not affect quantitation of drugs with a wide range of plasma protein binding levels in human plasma. With the confirmation that there is no impact on quantification from the matrix, the bioanalytical method can be used to support the pharmacokinetic evaluations for clinical studies in special populations.

Multicomponent solid forms of the uric acid reabsorption inhibitor lesinurad and cocrystal polymorphs with urea: DFT simulation and solubility study.

Lesinurad (systematic name: 2-{[5-bromo-4-(4-cyclopropylnaphthalen-1-yl)-4H-1,2,4-triazol-3-yl]sulfanyl}acetic acid, C17H14BrN3O2S) is a selective uric acid reabsorption inhibitor related to gout, which exhibits poor aqueous solubility. High-throughput solid-form screening was performed to screen for new solid forms with improved pharmaceutically relevant properties. During polymorph screening, we obtained two solvates with methanol (CH3OH) and ethanol (C2H5OH). Binary systems with caffeine (systematic name: 3,7-dihydro-1,3,7-trimethyl-1H-purine-2,6-dione, C8H10N4O2) and nicotinamide (C6H6N2O), polymorphs with urea (CH4N2O) and eutectics with similar drugs, like allopurinol and febuxostat, were prepared using the crystal engineering approach. All these novel solid forms were confirmed by XRD, DSC and FT-IR. The crystal structures were solved by single-crystal and powder X-ray diffraction. The crystal structures indicate that the lesinurad molecule is highly flexible and the triazole moiety, along with the rotatable thioacetic acid (side chain) and cyclopropane ring, is almost perpendicular to the planar naphthalene moiety. The carboxylic acid-triazole heterosynthon in the drug is interrupted by the presence of methanol and ethanol molecules in their crystal structures and forms intermolecular macrocyclic rings. The caffeine cocrystal maintains the consistency of the acid-triazole heterosynthons as in the drug and, in addition, they are bound by several auxiliary interactions. In the binary system of nicotinamide and urea, the acid-triazole heterosynthon is replaced by an acid-amide synthon. Among the urea cocrystal polymorphs, Form I (P-1, 1:1) consists of an acid-amide (urea) heterodimer, whereas in Form II (P21/c, 2:2), both acid-amide heterosynthons and urea-urea dimers co-exist. Density functional theory (DFT) calculations further support the experimentally observed synthon hierarchies in the cocrystals. Aqueous solubility experiments of lesinurad and its binary solids in pH 5 acetate buffer medium indicate the apparent solubility order lesinurad-urea Form I (43-fold) > lesinurad-caffeine (20-fold) > lesinurad-allopurinol (12-fold) ≃ lesinurad-nicotinamide (11-fold) > lesinurad, and this order is correlated with the crystal structures.

Effects of Food and Antacids on Pharmacokinetics and Pharmacodynamics of Lesinurad, a Selective Urate Reabsorption Inhibitor.

Two clinical studies were performed in healthy volunteers to investigate food and antacid effects on lesinurad, a novel selective uric acid reabsorption inhibitor approved for treatment of hyperuricemia associated with gout in combination with xanthine oxidase inhibitors. Study 1 evaluated a high-fat, high-calorie meal or high doses of antacids (3000mg calcium carbonate or 1600mg magnesium hydroxide/1600mg aluminum hydroxide) on the pharmacokinetics (PK) and pharmacodynamics (PD) of 400mg oral lesinurad. Study 2 evaluated low doses of antacids (1250mg calcium carbonate or 800mg magnesium hydroxide/800mg aluminum hydroxide) on the PK and PD of 400mg lesinurad. Food did not alter the plasma AUC of lesinurad and only reduced its Cmax by 18%. In the fasted conditions, high-dose calcium carbonate reduced the Cmax and AUC of lesinurad by 54% and 38%, respectively, whereas high-dose magnesium hydroxide/aluminum hydroxide reduced Cmax and AUC by 36% and 31%, respectively. Food enhanced the maximum serum urate (sUA)-lowering effect of lesinurad by approximately 20% despite reducing the Cmax of lesinurad. High-dose calcium carbonate decreased the urate-lowering effect approximately 20% in the first 6hours, whereas high-dose magnesium hydroxide/aluminum hydroxide reduced the effect by 26%. Low-dose calcium carbonate or magnesium hydroxide/aluminum hydroxide in the presence of food did not significantly affect plasma lesinurad Cmax and AUC or the sUA lowering and renal handling of uric acid. In summary, study results suggest food did not meaningfully alter lesinurad PK and PD. High doses of antacids reduced lesinurad AUC up to 40% and reduced the lesinurad uric acid-lowering effect.

Different Mathematical Spectrophotometric Methods for Determination of Lesinurad in the Presence of its Oxidative Degradation Product

Lesinurad is a novel selective uric acid reabsorption inhibitor which has been recently approved for the treatment of the chronic gout. Four simple mathematical spectrophotometric methods have been developed for the quantitative and selective determination of lesinurad in the presence of its oxidative degradation product. Complete oxidative degradation of lesinurad to its degradation product has been done. The developed methods namely, ratio difference spectrophotometric, first derivative of the ratio spectra, mean centering of the ratio spectra and continuous wavelet transform spectrophotometric methods. These methods have been developed and optimized to resolve the existed overlapping between the zero order UV absorption spectra of lesinurad and its oxidative degradation product. The described spectrophotometric methods have achieved selective determination of lesinurad without any interference from the oxidative degradation product. Also, they have been validated and applied for quantitative analysis of the studied drug in its new pharmaceutical preparation.

Lesinurad in hyperuricaemia of gout: a profile of its use in the EU

Up to 90% of gout patients experience low uric acid (UA) excretion rather than high UA production. The selective UA reabsorption inhibitor lesinurad (Zurampic®) is an effective and generally well tolerated option for the adjunctive treatment of hyperuricaemia in patients with gout who have not achieved target serum uric acid (sUA) levels with monotherapy with an adequate dosage of a xanthine oxidase inhibitor, a class of drugs that acts on UA production. In phase 3 trials of lesinurad + allopurinol in adults with gout inadequately responsive to allopurinol, and lesinurad + febuxostat in adults with tophaceous gout, the addition of once-daily oral lesinurad enabled many patients to achieve target sUA levels, and improved clinical parameters (e.g. tophus number/size) in the long term.

Pharmacokinetics, Pharmacodynamics, and Tolerability of Concomitant Multiple Dose Administration of Verinurad (RDEA3170) and Allopurinol in Adult Male Subjects With Gout.

Verinurad (RDEA3170) is a selective uric acid reabsorption inhibitor in clinical development for treatment of hyperuricemia and gout. This phase 1b, multiple‐dose, drug‐drug interaction study evaluated the pharmacokinetics, pharmacodynamics, and tolerability of verinurad in combination with allopurinol. Adult males with gout were randomized to receive once‐daily oral doses of allopurinol 300 mg or verinurad 10 mg alone for 7 days, allopurinol 300 mg + verinurad 10 mg on days 8 to 14, and the alternative single agent on days 15 to 21. Colchicine 0.6 mg was taken prophylactically for gout flares. Plasma/serum and urine samples were assayed for verinurad, allopurinol, oxypurinol (allopurinol active metabolite), colchicine (plasma only), and uric acid. Safety was assessed by adverse events (AEs) and laboratory tests. Verinurad plasma exposure was unaffected by allopurinol. Verinurad increased the maximum observed plasma concentration (Cmax) for allopurinol by 33%; the area under the plasma concentration‐time curve (AUC) was unaffected. Oxypurinol Cmax and AUC were reduced 32% and 38%, respectively, by verinurad. Colchicine plasma exposure was unaltered by verinurad. The maximum decrease in serum urate was greater with verinurad + allopurinol (65%) than with verinurad (51%) or allopurinol (43%) alone. Compared with the baseline rate, the maximum rate of uric acid excreted in urine was +56% with verinurad, −46% with allopurinol, and unchanged with verinurad + allopurinol. No serious AEs, discontinuations due to AEs, or clinically significant laboratory abnormalities were noted. Despite decreased systemic exposure of allopurinol and oxypurinol in the presence of verinurad, the combination resulted in greater serum urate reduction compared with either drug alone and was well tolerated at the studied doses.

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.

Validated Stability Indicating High Performance Liquid Chromatographic Determination of Lesinurad.

Lesinurad is a novel selective uric acid reabsorption inhibitor which has been newly approved for the treatment of the chronic gout. The behavior of lesinurad under various stress conditions (hydrolysis, oxidation, thermal and photolysis) has been investigated as per ICH guidelines. The drug has been found to be labile to acidic hydrolysis, basic hydrolysis and oxidation but stable in neutral, thermal and photolytic conditions. A high performance liquid chromatographic method has been developed for selective determination of the studied drug in the presence of its related degradation products. Good chromatographic resolution has been achieved using a reversed phase BDS Hypersil C18 stationary phase with an isocratic elution of a mobile phase consists of acetonitrile:water (65:35, v/v) at a flow rate of 1 mL/min and UV detection at 290 nm. Two degradation products have been identified by IR and mass spectral scans. The method was validated according to ICH guidelines. The linearity range has been found to be acceptable over the concentration range of 1-20 μg/mL. The developed method has been successfully applied for the estimation of lesinurad in its pharmaceutical dosage form and could be used for the routine analysis of the studied drug in the quality control laboratories.

Second derivative spectrophotometric and synchronous spectrofluorometric determination of lesinurad in the presence of its oxidative degradation product

Lesinurad is a novel selective uric acid reabsorption inhibitor which has been recently approved for the treatment of chronic gout.

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

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. 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. 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. 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. ClinicalTrials.gov (http://clinincaltrials.gov), NCT01508702.

Evaluation of Pharmacokinetic Interactions Between Lesinurad, a New Selective Urate Reabsorption Inhibitor, and Commonly Used Drugs for Gout Treatment.

Lesinurad is a novel selective uric acid reabsorption inhibitor approved for treatment of hyperuricemia associated with gout in combination with xanthine oxidase inhibitors (XOIs). Open-label pharmacokinetic studies were performed in volunteers or subjects with hyperuricemia (serum uric acid ≥ 8 mg/dL) to investigate interactions of lesinurad (with and without concurrent XOIs) with colchicine and 2 nonsteroidal anti-inflammatory drugs: naproxen and indomethacin. Colchicine studies included consecutive 7-day treatment periods of (1) allopurinol 300 mg, allopurinol 300 mg plus lesinurad 400 or 600 mg, and continued lesinurad 400 or 600 mg; or (2) febuxostat 40 or 80 mg, febuxostat 40 or 80 mg plus lesinurad 400 mg, and continued febuxostat 40 or 80 mg plus lesinurad 600 mg. Naproxen and indomethacin studies included lesinurad 400 mg on day 1, naproxen 250 mg twice daily or indomethacin 25 mg twice daily on days 2-6, and lesinurad 400 mg plus continued naproxen or indomethacin on days 7-13 and the morning of day 14. Lesinurad did not alter the pharmacokinetics of naproxen and modestly altered exposure to colchicine (AUC decrease of ≤ 25%) and indomethacin (AUC increase of ∼35%). Indomethacin did not alter the pharmacokinetics of lesinurad, whereas naproxen modestly decreased the Cmax of lesinurad by ∼27%.

Evaluation of Pharmacokinetic Interactions Between Lesinurad, a New Selective Urate Reabsorption Inhibitor, and CYP Enzyme Substrates Sildenafil, Amlodipine, Tolbutamide, and Repaglinide.

Lesinurad is a selective uric acid reabsorption inhibitor approved for the treatment of hyperuricemia associated with gout in combination with xanthine oxidase inhibitors. In vitro assays indicate that lesinurad is an inducer of CYPs in the order CYP3A > CYP2C8 > CYP2C9 > CYP2C19 > CYP2B6 and an inhibitor of CYP2C8 and CYP2C9. To investigate the drug interaction potential of lesinurad, clinical drug interaction studies were conducted. Open-label studies in volunteers investigated the effects of single-/multiple-dose lesinurad on the pharmacokinetics of sildenafil and amlodipine (CYP3A4 induction), tolbutamide (CYP2C9 inhibition/induction), and repaglinide (CYP2C8 inhibition/induction). There was no apparent induction of CYP2C8 and CYP2C9 following repeated lesinurad administration, although no inhibition of CYP2C9 and modest inhibition of CYP2C8 were observed following single-dose lesinurad. Consistent with in vitro observations, lesinurad (200 mg once daily) was an inducer of CYP3A based on the effects on sildenafil exposure. Sildenafil exposure decreased by approximately 34% for Cmax and AUC when administered with multiple-dose lesinurad 200 mg and allopurinol 300 mg, relative to sildenafil alone. During lesinurad therapy, the possibility of reduced efficacy of concomitant drugs that are CYP3A substrates should be considered and their efficacy monitored because of induction of CYP3A by lesinurad.

Lesinurad Combined With Allopurinol: A Randomized, Double-Blind, Placebo-Controlled Study in Gout Patients With an Inadequate Response to Standard-of-Care Allopurinol (a US-Based Study).

Lesinurad is a selective uric acid reabsorption inhibitor used for the treatment of gout in combination with a xanthine oxidase inhibitor. The Combining Lesinurad with Allopurinol Standard of Care in Inadequate Responders (CLEAR 1) study, a 12-month, multicenter, randomized, double-blind, placebo-controlled phase III trial, was conducted to investigate daily lesinurad (200 mg or 400 mg orally) added to allopurinol versus placebo plus allopurinol in patients with serum urate (UA) levels above a target of <6.0 mg/dl. Patients receiving ≥300 mg of allopurinol (≥200 mg in those with moderate renal impairment) who had serum UA levels ≥6.5 mg/dl at screening and ≥2 gout flares during the previous year were studied. The primary end point was the proportion of patients achieving a serum UA level of <6.0 mg/dl at month 6. Key secondary end points were the mean gout flare rate requiring treatment (months 7-12) and the proportions of patients with complete resolution of ≥1 target tophus (month 12). Safety assessments included adverse events and laboratory data. The study patients (n = 603) were predominantly male and had a mean ± SD age of 51.9 ± 11.3 years, a gout duration of 11.8 ± 9.4 years, a baseline serum UA level of 6.94 ± 1.27 mg/dl, and were receiving an allopurinol dosage of 306.6 ± 59.58 mg/day. Lesinurad at doses of 200 mg or 400 mg added to allopurinol therapy significantly increased the proportions of patients who achieved serum UA target levels by month 6 as compared with those receiving allopurinol alone (54.2%, 59.2%, and 27.9%, respectively, P < 0.0001). Lesinurad was not significantly superior to allopurinol alone in terms of the secondary end points: rates of gout flares and complete resolution of tophi. Lesinurad was generally well-tolerated; the safety profile of the 200-mg dose was comparable to that of allopurinol alone, except for higher incidences of predominantly reversible elevations of serum creatinine levels. Lesinurad added to allopurinol provided benefit as compared with allopurinol alone in reducing serum UA levels and represents a new treatment option for patients needing additional urate-lowering therapy.

Supratherapeutic dose evaluation and effect of lesinurad on cardiac repolarization: a thorough QT/QTc study.

IntroductionLesinurad is a selective uric acid reabsorption inhibitor approved in the United States and Europe for treatment of gout in combination with a xanthine oxidase inhibitor. A maximum tolerated dose study was conducted to determine the lesinurad supratherapeutic dose, followed by a thorough QTc study to characterize the effect of lesinurad on cardiac repolarization.MethodsThe maximum tolerated dose study was a randomized, double-blind, placebo-controlled, single-ascending dose study that enrolled 35 healthy men and women. Lesinurad plasma exposure (maximum observed plasma concentration and area under the plasma concentration versus time curve) was determined at doses of 800 mg, 1,200 mg, and 1,600 mg. The thorough QTc study was a double-blind, four-period, placebo-controlled crossover study with 54 healthy men and women who received single doses of lesinurad 1,600 mg (supratherapeutic dose), lesinurad 400 mg, moxifloxacin 400 mg, and placebo in randomized sequence. Digital 12-lead electrocardiograms were recorded at eleven time points over 24 hours in each treatment period. QT intervals were corrected for heart rate using an individual-specific correction factor (QTcI).ResultsThe upper bound of the one-sided 95% confidence interval for time-matched, placebo-subtracted, baseline-adjusted QTcI intervals (ΔΔQTcI) was <10 ms for both the lesinurad 400 mg and 1,600 mg doses. ΔΔQTcI was independent of lesinurad concentrations. No QTcI thresholds >480 ms or QTcI increases >30 ms were observed. Moxifloxacin mean QTcI intervals were >5 ms, and the lower bounds of the 90% confidence interval were >5 ms at 2 hours, 3 hours, and 4 hours, confirming assay sensitivity.ConclusionLesinurad, at supratherapeutic doses, does not have a significant effect on the QT interval in healthy male or female subjects.

In Vitro and In Vivo Interaction Studies Between Lesinurad, a Selective Urate Reabsorption Inhibitor, and Major Liver or Kidney Transporters.

Background and ObjectivesLesinurad is a selective uric acid reabsorption inhibitor (SURI) under investigation for the treatment of gout. This study elucidated the interaction of lesinurad with major liver and kidney transporters in vitro and evaluated the drug–drug interactions (DDIs) of lesinurad and atorvastatin, metformin, and furosemide in clinical studies.MethodsLesinurad interaction with membrane transporters was evaluated in validated transporter-expressing cell systems and analyzed by liquid scintillation counting. Healthy male subjects (ages 18–65 years; body mass index 18–32 kg/m2) received atorvastatin (40 mg; n = 28) with or without lesinurad 200 or 400 mg, or received metformin (850 mg; n = 12) or furosemide (40 mg; n = 11) with or without lesinurad 400 mg. Plasma concentrations of each concomitant drug were determined by validated liquid chromatography with tandem mass spectrometry methods.ResultsLesinurad interacted in vitro with OATP1B1, OCT1, and OAT1/3 transporters. Co-administration of lesinurad 200 mg did not significantly alter plasma exposure (maximum concentration [Cmax] and area under the concentration–time curve [AUC]) of total atorvastatin (atorvastatin + hydroxyl-metabolites) or atorvastatin, while co-administration of lesinurad 400 mg increased the Cmax of total atorvastatin and atorvastatin by 17–26 %, but had no effect on AUC. Co-administration of lesinurad 400 mg had no effect on the plasma exposure of metformin. Furosemide plasma AUC was reduced by 31 % in the presence of lesinurad 400 mg, but furosemide renal clearance and diuretic activity were unchanged.ConclusionsNo clinically relevant DDIs were observed between lesinurad and substrates of major liver or kidney transporters.

Lesinurad in combination with allopurinol: results of a phase 2, randomised, double-blind study in patients with gout with an inadequate response to allopurinol

ObjectivesTo assess the efficacy and tolerability of lesinurad, an oral selective uric acid reabsorption inhibitor, in combination with allopurinol versus allopurinol alone in patients with gout and an inadequate response...

SAT0521 Lesinurad, an Inhibitor of the Uric Acid Transporter URAT1 and A Potential Therapy for Gout, Requires URAT1 Phenylalanine 365 for High Affinity Inhibition

BackgroundIn most patients, gout is caused by inefficient excretion of uric acid, resulting in hyperuricemia and the formation of crystal deposits of uric acid. The renal uric acid transporter URAT1...

Pharmacodynamic, pharmacokinetic and tolerability evaluation of concomitant administration of lesinurad and febuxostat in gout patients with hyperuricaemia

The aim of this study was to evaluate the pharmacodynamics (PDs), pharmacokinetics (PKs) and safety of lesinurad (selective uric acid reabsorption inhibitor) in combination with febuxostat (xanthine oxidase inhibitor) in patients with gout. This study was a phase IB, multicentre, open-label, multiple-dose study of gout patients with serum uric acid (sUA) >8 mg/dl following washout of urate-lowering therapy with colchicine flare prophylaxis. Febuxostat 40 or 80 mg/day was administered on days 1-21, lesinurad 400 mg/day was added on days 8-14 and then lesinurad was increased to 600 mg/day on days 15-21. sUA, urine uric acid and PK profiles were evaluated at the end of each week. Safety was assessed by adverse events, laboratory tests and physical examinations. Initial treatment with febuxostat 40 or 80 mg/day monotherapy resulted in 67% and 56% of subjects, respectively, achieving a sUA level <6 mg/dl. Febuxostat 40 or 80 mg/day plus lesinurad 400 or 600 mg/day resulted in 100% of subjects achieving sUA <6 mg/dl and up to 100% achieving sUA <5 mg/dl. No clinically relevant changes in the PKs of either drug were noted. The combination was well tolerated. The clinically important targets of sUA <6 mg/dl and <5 mg/dl are achievable in 100% of patients when combining lesinurad and febuxostat.