Combination Treatment Study in Subjects With Tophaceous Gout With Lesinurad and Febuxostat (CRYSTAL)
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ClinicalTrials.gov Identifier: NCT01510769 |
Recruitment Status :
Completed
First Posted : January 16, 2012
Results First Posted : May 26, 2016
Last Update Posted : May 26, 2016
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Tophaceous Gout | Drug: Lesinurad Drug: Placebo Drug: Febuxostat | Phase 3 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 330 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Triple (Participant, Care Provider, Investigator) |
Primary Purpose: | Treatment |
Official Title: | A Phase 3 Randomized, Double-Blind, Multicenter, Placebo- Controlled, Combination Study to Evaluate the Efficacy and Safety of Lesinurad and Febuxostat Compared to Febuxostat Alone at Lowering Serum Uric Acid and Resolving Tophi in Subjects With Tophaceous Gout |
Study Start Date : | January 2012 |
Actual Primary Completion Date : | June 2014 |
Actual Study Completion Date : | June 2014 |

Arm | Intervention/treatment |
---|---|
Experimental: lesinurad 400 mg + febuxostat 80 mg |
Drug: Lesinurad
Tablets, 400 mg once daily (QD) Drug: Febuxostat 80 mg |
Experimental: lesinurad 200 mg + febuxostat 80 mg |
Drug: Lesinurad
Tablets, 200 mg QD Drug: Febuxostat 80 mg |
Placebo Comparator: placebo + febuxostat 80 mg |
Drug: Placebo
Tablets, Placebo QD Drug: Febuxostat 80 mg |
- Subjects With a Serum Urate (sUA) Level That is < 5.0 mg/dL by Month 6 [ Time Frame: 6 months, analysis after all subjects complete 12 months ]Proportion of subjects with an sUA level that is < 5.0 mg/dL by Month 6
- Complete Resolution of at Least One Target Tophus [ Time Frame: 12 Months ]Proportion of subjects who experience complete resolution of at least 1 target tophus by Month 12
- Complete or Partial Response of at Least One Tophus [ Time Frame: 12 Months ]Proportion of subjects with a best tophus response on at least 1 target tophus of complete (disappearance of at least 1 target tophus) or partial (≥ 50% decrease in the area of at least 1 target tophus) resolution by Month 12
- Quality of Life [ Time Frame: 12 Months ]Proportion of subjects with an improvement from Baseline in Health Assessment Questionnaire - Disability Index (HAQ-DI) of at least 0.25 at Month 12. The HAQ-DI assesses a patient's level of functional ability with items scores ranging from 0-3 with 0 being the least disability.

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Ages Eligible for Study: | 18 Years to 85 Years (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Subject is able to understand the study procedures, the risks involved and willing to provide written informed consent before the first study related activity.
- Subject is willing to adhere to the visit/protocol schedules.
- Subject meets the diagnosis of gout as per the American Rheumatism Association
- Criteria for the Classification of Acute Arthritis of Primary Gout.
- Subject meets one of the following criteria:
- Subjects who are not currently taking an approved ULT must have an sUA value of ≥ 8 mg/dL (476 µmol/L).
- Subjects entering the study on a medically appropriate dose of febuxostat or allopurinol must have an sUA value of ≥ 6.0 mg/dL (357 µmol/L).
- Subject must be able to take gout flare prophylaxis with colchicine or non-steroidal anti-inflammatory drug (NSAID) (including Cox-2 selective NSAID) ± PPI.
- Subject with at least 1 measurable tophus on the hands/wrists and/or feet/ankles ≥ 5 mm and ≤ 20 mm in the longest diameter.
- Body mass index (BMI) < 45 kg/m2
Exclusion Criteria:
- Subject with known hypersensitivity or allergy to febuxostat.
- Subject who is taking any approved urate-lowering medication other than allopurinol or febuxostat that is indicated for the treatment of gout within 8 weeks of the Screening Visit.
- Subject who previously received pegloticase.
- Subject who consumes more than 14 drinks of alcohol per week (eg, 1 drink = 5 oz [150 mL] of wine, 12 oz [360 mL] of beer, or 1.5 oz [45 mL] of hard liquor).
- Subject with a history or suspicion of drug abuse within the past 5 years.
- Subject with a history of myositis/myopathy or rhabdomyolysis.
- Subject that requires or may require systemic immunosuppressive or immunomodulatory treatment.
- Subject with known or suspected human immunodeficiency virus (HIV) infection.
- Subject with a positive test for active hepatitis B or hepatitis C infection.
- Subject with a history of malignancy within the previous 5 years with the exception of non-melanoma skin cancer that has been treated with no evidence of recurrence, treated cervical dysplasia or treated in situ Grade 1 cervical cancer.
- Subject within the last 12 months with: unstable angina, New York Heart Association thrombosis; or subjects currently receiving anticoagulants.
- Subject with uncontrolled hypertension.
- Subject with an estimated creatinine clearance < 30 mL/min.
- Subjects with a creatine kinase > 2.5 x ULN at any time during the Screening Period.
- Subject with active peptic ulcer disease requiring treatment.
- Subject with a history of xanthinuria, active liver disease, or hepatic dysfunction.
- Subject receiving chronic treatment with more than 325 mg of salicylates per day.
- Subject taking valpromide, progabide, or valproic acid.
- Subject who has received an investigational therapy within 8 weeks or 5 half-lives (whichever is longer) prior to the Screening Visit.
- Subject with any other medical or psychological condition, which in the opinion of the Investigator and/or Medical Monitor, might create undue risk to the subject or interfere with the subject's ability to comply with the protocol requirements, or to complete the study.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01510769

Study Director: | Chris Storgard, MD | Ardea Biosciences, Inc. |
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Ardea Biosciences, Inc. |
ClinicalTrials.gov Identifier: | NCT01510769 |
Other Study ID Numbers: |
RDEA594-304 2011-003768-55 ( EudraCT Number ) |
First Posted: | January 16, 2012 Key Record Dates |
Results First Posted: | May 26, 2016 |
Last Update Posted: | May 26, 2016 |
Last Verified: | April 2016 |
Gout Arthritis Joint Diseases Musculoskeletal Diseases Crystal Arthropathies Rheumatic Diseases Purine-Pyrimidine Metabolism, Inborn Errors Metabolism, Inborn Errors |
Genetic Diseases, Inborn Metabolic Diseases Febuxostat Lesinurad Gout Suppressants Antirheumatic Agents Uricosuric Agents Renal Agents |