A Phase 2 Trial of Dotinurad in Xanthine Oxidase Inhibitor (XOI) Intolerant/Uricase Failure Gout Participants

A Phase 2, Randomized, Double-blind, Placebo-controlled, Multicenter Study to Evaluate the Efficacy and Safety of Dotinurad in Adult Participants With Gout Who Are Intolerant to Xanthine Oxidase Inhibitors or Failed Uricase Treatment

The primary objective of this trial is to evaluate the efficacy of dotinurad in lowering serum uric acid (sUA) at Week 24 in participants with gout who are XOI intolerant or have failed uricase treatment.

Study Overview

• Status: Recruiting
• Conditions: Gout
• Intervention / Treatment: Drug: Dotinurad; Other: Placebo

• Study Type: Interventional
• Enrollment (Estimated): 90
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Clinical Trial Lead; Phone Number: (858) 356-4740; Email: ClinicalTrials@crystalystx.com

Study Locations

• United States
  • California
    • Granada Hills, California, United States, 91344
      • Recruiting
      • Amicis Research Center
      • Contact: Pascal Dabel, MD
    • Thousand Oaks, California, United States, 91360
      • Recruiting
      • Cohen Medical Center
      • Contact: Shariar Cohen-Gadol, MD
  • Florida
    • DeBary, Florida, United States, 32713
      • Recruiting
      • Omega Research Group
      • Contact: Kwabena Ayesu, MD
    • Lakeland, Florida, United States, 33805
      • Recruiting
      • Clinical Research of Central Florida
      • Contact: Michael Gimness, MD
    • Miami, Florida, United States, 33014
      • Recruiting
      • Panax Clinical Research
      • Contact: Robert Perry, MD
    • Miami, Florida, United States, 33176
      • Recruiting
      • Anchor Medical Research
      • Contact: Juvenal Martinez, MD
  • Maryland
    • Oxon Hill, Maryland, United States, 20745
      • Recruiting
      • MD Medical Research
      • Contact: Stephen Ong, MD
  • Michigan
    • Saint Clair Shores, Michigan, United States, 48081
      • Recruiting
      • Clinical Research Institute of Michigan
      • Contact: Amar Majjhoo, MD
    • Sterling Heights, Michigan, United States, 48313
      • Recruiting
      • Revival Research Institute
      • Contact: Syed Husain, MD
  • Nevada
    • Las Vegas, Nevada, United States, 89030
      • Recruiting
      • Las Vegas Clinical Trials
      • Contact: Alton Walters, MD
  • New York
    • Brooklyn, New York, United States, 11215
      • Recruiting
      • Ellipsis Research Group
      • Contact: Jorge Serje, MD
    • Hartsdale, New York, United States, 10530
      • Recruiting
      • Drug Trials America
      • Contact: Michael Gerdis, MD
  • North Carolina
    • Shelby, North Carolina, United States, 28150
      • Recruiting
      • Shelby Clinical Research
      • Contact: Christian Martin, MD
  • Texas
    • Dallas, Texas, United States, 75230
      • Recruiting
      • Zenos Clinical Research
      • Contact: Bachar Elsaadi, MD
    • DeSoto, Texas, United States, 75115
      • Recruiting
      • Epic Medical Research
      • Contact: Haresh Boghara, MD
    • Houston, Texas, United States, 77479
      • Recruiting
      • Pioneer Research Solutions
      • Contact: Francisco Velazquez, MD
    • Tomball, Texas, United States, 77375
      • Recruiting
      • DM Clinical Research
      • Contact: Shaikh Ali, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Between 18 and 75 years of age (inclusive) at the time of signing informed consent.

2. Diagnosis of gout based on 2015 American College of Rheumatology (ACR)-European Union League Against Rheumatism (EULAR) criteria for at least 1 year and has at least 1 of the following:

   • History (either by medical record or participant interview) of intolerance or a contraindication to either allopurinol or febuxostat.
   • Failed uricase treatment (eg, an sUA level >6.0 mg/dL at least 2 weeks after last infusion; intolerant or contraindicated to uricase treatment).
3. sUA level >6.0 and <10.5 mg/dL at both Screening Visit 1 (Day -28 Visit) and Screening Visit 2 (Day -7 Visit).
4. Female participants of childbearing potential must have a negative serum pregnancy test at Screening Visit 1 (Day -28 Visit), a negative urine pregnancy test on Day 1, and must not be breastfeeding.
5. Fertile male participants and female participants of childbearing potential must be willing to completely abstain from heterosexual sex or agree to use acceptable contraception from the time of signing informed consent through 30 days after the last dose of trial drug.

Exclusion Criteria:

1. History of or presence of kidney stones within 1 year prior to Screening.
2. History of or presence of malignancy in the last 5 years other than treated cutaneous basal or squamous cell carcinoma.
3. Known or suspected history of drug abuse, a positive drug test at Screening Visit 1, or a recent history of alcohol abuse.
4. Known history of or positive results for human immunodeficiency virus (HIV), Hepatitis B surface antigen (HBsAg), or Hepatitis C virus (HCV) during Screening.
5. Current or historical evidence of any clinically significant disease or condition that, in the opinion of the Investigator, may compromise participant safety or trial compliance or may confound interpretation of trial results.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Dotinurad; The Treatment Period will consist of 2 consecutive parts: a 24-week period where participants will take dotinurad (Treatment Period 1) followed by a 12-week period where participants will continue to take dotinurad (Treatment Period 2).	Drug: Dotinurad; Over-encapsulated tablets containing active drug substance administered orally.
Experimental: Placebo + Placebo to Dotinuard; The Treatment Period will consist of 2 consecutive parts: a 24-week period where participants will take placebo (Treatment Period 1) followed by a 12-week treatment period where participants will take dotinurad (Treatment Period 2).	Drug: Dotinurad; Over-encapsulated tablets containing active drug substance administered orally.; Other: Placebo; Capsules containing microcrystalline cellulose administered orally.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Percentage of Participants With an sUA Level <6.0 mg/dL at Week 24	Week 24

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean Change From Baseline in sUA at Week 24		Baseline and Week 24
Percentage of Participants With an sUA Level <6.0 mg/dL at Weeks 16, 20 and 24		Weeks 16, 20 and 24
Percentage of Participants With an sUA Level <6.0 <5.0, <4.0, and <3.0 mg/dL at Each Visit		Up to Week 40
Absolute Change from Baseline in sUA Levels at Each Visit		Baseline to Week 40
Percent Change from Baseline in sUA Levels at Each Visit		Baseline to Week 40
Number of Participants With Treatment-emergent Adverse Events (TEAEs) and Serious Adverse Events (SAEs) in Treatment Periods 1 and 2	Any clinically significant changes from baseline in safety laboratory values and vital signs will be reported as AEs per investigators discretion.	Screening to Week 36
Number of Participants With TEAEs and SAEs Throughout the Study	Any clinically significant changes from baseline in safety laboratory values and vital signs will be reported as AEs per investigators discretion.	Screening to Week 40

Collaborators and Investigators

• Sponsor: Crystalys Therapeutics

Publications and helpful links

Helpful Links

• Related Info
• Related Info

Study record dates

Study Major Dates

• Study Start (Actual): May 8, 2026
• Primary Completion (Estimated): July 1, 2027
• Study Completion (Estimated): August 1, 2027

Study Registration Dates

• First Submitted: April 10, 2026
• First Submitted That Met QC Criteria: April 10, 2026
• First Posted (Actual): April 16, 2026

Study Record Updates

• Last Update Posted (Actual): June 10, 2026
• Last Update Submitted That Met QC Criteria: June 8, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: Dotinurad; Xanthine Oxidase Inhibitors
• Additional Relevant MeSH Terms: Crystal Arthropathies; Musculoskeletal Diseases; Arthritis; Joint Diseases; Rheumatic Diseases; Purine-Pyrimidine Metabolism, Inborn Errors; Metabolism, Inborn Errors; Genetic Diseases, Inborn; Metabolic Diseases; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Nutritional and Metabolic Diseases; Gout; dotinurad
• Other Study ID Numbers: FYU-981-CRYS-201

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Individual participant data that underlie the results reported for publication, after deidentification.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No