Patient case (clinical description): A 39-year-old man comes to the emergency department with an acute onset of severe left toe pain.  The toe is red and exhibits swelling. The patient is not febrile, and does not remember any recent trauma. Medical history is not significant except for the similar attacks and the diagnosis of gouty arthritis. His medication history includes Allopurinol to prevent gouty attacks. His father has the same medical condition. However, his older brother who is 41 years old is healthy with no history of gouty arthritis. Physical examination shows a swollen, tender first metatarsophalangeal joint.  Aspiration of the joint showed high leukocyte count, negative Gram stain, and numerous needle-shaped crystals, which is compatible with gouty arthritis.

Patient's own account: I'm a 39-year-old man and got admitted to the ER after an unbearable pain in my left toe. My toe was red and terribly swollen. I was still standing on my feet, not febrile and I don't remember hitting my head or anything. I don't have any special medical history, but I had been diagnosed with gout before. I take Lopurin to prevent my gouty attacks. My dad had the same problem, but my 41-year-old brother is healthy and does not have gouty attacks. The doctor did a physical exam and found that the joints between my toes and the rest of my foot were swollen and tender. The doctor renewed his diagnosis of gouty arthritis.

Clinical trial: Efficacy and Safety of Extended Release and Immediate Release Febuxostat in Participants With Gout

Eligibility criteria:
Inclusion Criteria:

          1. In the opinion of the investigator, the participant is capable of understanding and
             complying with protocol requirements.

          2. The participant or, when applicable, the participant's legally acceptable
             representative signs and dates a written, informed consent form and any required
             privacy authorization prior to the initiation of any study procedure.

          3. Has a history or presence of gout defined as having one or more of the American
             Rheumatism Association (ARA) criteria for the diagnosis of gout:

               1. A tophus proven to contain urate crystals by chemical or polarized light
                  microscopic means, AND/OR;

               2. Characteristic urate crystals in the joint fluid, AND/OR;

               3. History of at least 6 of the following clinical, laboratory, and x-ray phenomena:

             i. more than one attack of acute arthritis, ii. maximum inflammation developed within
             1 day, iii. monoarticular arthritis, iv. redness observed over joints, v. first
             metatarsophalangeal joint painful or swollen, vi. unilateral first metatarsophalangeal
             joint attack, vii. unilateral tarsal joint attack, viii. tophus (proven or suspected),
             ix. Hyperuricemia, x. asymmetric swelling within a joint on x-ray, xi. subcortical
             cysts without erosions on x-ray; xii. joint fluid culture negative for organisms
             during attack.

          4. Is male or female at least 18 years of age, inclusive.

          5. A female participant of childbearing potential who is sexually active with a
             nonsterilized male partner agrees to use routinely adequate contraception from signing
             of informed consent throughout the duration of the study.

          6. Have a serum urate (sUA) level ≥8.0 mg/dL at the Day -4 Visit or at the retest visit.

          7. Has an estimated Glomerular Filtration Rate (eGRF) ≥15 mL/min using the Modification
             of Diet in Renal Disease (MDRD) formula at the Screening visit (Day -21 for
             participants on urate lowering therapy (ULT) and Day -4 for participants not on ULT)
             or at the retest visit.

          8. Has at least one gout flare within 12 months prior to Screening visit.

        Exclusion Criteria:

          1. Has received any investigational compound within 30 days prior to Screening.

          2. Is an immediate family member, study site employee, or is in a dependent relationship
             with a study site employee who is involved in conduct of this study (eg, spouse,
             parent, child, sibling) or may consent under duress.

          3. Is breastfeeding or pregnant.

          4. Has secondary hyperuricemia (eg, due to myeloproliferative disorder).

          5. Has a history of xanthinuria.

          6. Has received ULT (ie, allopurinol, probenecid, etc.) within 20 days prior to Day
             1/Randomization Visit.

          7. Has a known hypersensitivity to febuxostat or any components of their formulation; has
             a known hypersensitivity to naproxen, any other nonsteroidal anti-inflammatory drug
             (NSAID), aspirin, lansoprazole, colchicine or any components in their formulation.

          8. Has active peptic ulcer disease.

          9. Has a history of cancer (other than basal cell carcinoma of the skin) within 5 years
             prior to the Screening Visit.

         10. Has alanine aminotransferase (ALT) and aspartate aminotransferase (AST) values >2 x
             the upper limit of normal (ULN).

         11. Has rheumatoid arthritis which requires treatment.

         12. Has a significant medical condition and/or conditions that would interfere with the
             treatment, safety, or compliance with the protocol.

         13. Has experienced a myocardial infarction (MI), stroke, hospitalized unstable angina,
             cardiac or cerebrovascular revascularization procedure or hospitalized transient
             ischemic attack (TIA) - except in participants who have severe renal impairment.

         14. Participants with severe renal impairment had a MI or stroke within 90 days prior to
             initial screening visit or has a MI or stroke during the screening period prior to Day
             1/Randomization Visit.

         15. Participant consumes >14 alcoholic beverages/week. Has a history of alcoholism or
             illicit drug abuse within 5 years.

         16. Has participated in another investigational study within the 30 days prior to the
             Screening Visit.

         17. Has a known history of infection with hepatitis B, hepatitis C, or human
             immunodeficiency virus.

         18. Is required to take excluded medications.
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 18 Years old.


Eligibility (NLI label): Entailment