Lesinurad and Febuxostat Combination Extension Study in Gout

Study Overview
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Brief Summary
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This study will assess the serum uric acid lowering effects and safety of lesinurad in combination with febuxostat over a long-term timeframe.

Detailed Description
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This is a Phase 3 extension study to assess the long-term efficacy and safety of lesinurad in combination with febuxostat in subjects who completed the double-blind treatment period in Study RDEA594-304.

Official Title
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A Long-Term Extension Study of Lesinurad in Combination With Febuxostat for Subjects With Gout Completing an Efficacy and Safety Study of Lesinurad and Febuxostat

Conditions
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Gout

Intervention / Treatment
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* Drug: lesinurad
* Drug: lesinurad
* Drug: febuxostat


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Subject is able to understand the study procedures and the risks involved and is willing to provide written informed consent before the first study related activity. Subject completed the double-blind treatment period in Study RDEA594-304 and was actively receiving and tolerating study medication (lesinurad or placebo) and febuxostat 80 mg at the Month 12 visit. Subject is male or female; female subjects of childbearing potential must agree to use an effective non-hormonal method of birth control during the study and for at least 14 days after the last dose of study medication. Exclusion Criteria: Subject has any medical or psychological condition, which in the opinion of the Investigator and/or the 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.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: lesinurad 400 mg + febuxostat 80 mg<br>Patients on lesinurad 400 mg had their dose changed to lesinurad 200 mg after implementation of protocol amendment 3, dated 07 October 2015. | Drug: lesinurad<br>* Tablets, 400 mg once daily (QD)<br>Drug: febuxostat<br>* Tabletsm 80 mg QD<br>|
| Experimental: lesinurad 200 mg + febuxostat 80 mg<br> | Drug: lesinurad<br>* Tablets, 200 mg QD<br>Drug: febuxostat<br>* Tabletsm 80 mg QD<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants With an sUA Level That is < 5.0 mg/dL | Percentage of participants in Study 307 With sUA < 5.0 mg/dL from the Core Studies 304 and Extension Study 307 - Observed Cases | Up to approximately 2.5 years (at Extension Month 12) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants (With at Least One Target Tophus at Baseline) Who Experience Complete Resolution of at Least One Target Tophus | Percentage of participants (With at Least One Target Tophus at Baseline) Who Experience Complete Resolution of at Least One Target Tophus During the Core and Extension Studies at Extension Month 12 (Observed Cases) | Up to approximatley 2.5 years (at Extension Month 12) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Gout