Title

Cardiovascular Safety of Febuxostat and Allopurinol in Participants With Gout and Cardiovascular Comorbidities (CARES)
A Multicenter, Randomized, Active-Control, Phase 3B Study to Evaluate the Cardiovascular Safety of Febuxostat and Allopurinol in Subjects With Gout and Cardiovascular Comorbidities
  • Phase

    Phase 3
  • Study Type

    Interventional
  • Study Participants

    6198
The purpose of this study is to see whether subjects with gout who receive febuxostat or allopurinol for up to 9 years have a higher rate of serious heart and blood vessel complications (major cardiovascular events).
The drug tested in this study was called Febuxostat (TMX-67). Febuxostat compared with allopurinol was evaluated for the cardiovascular (CV) safety in people with gout and significant CV comorbidities.

The study enrolled 6198 patients. Participants with a diagnosis of gout were enrolled in a 1:1 ratio to receive either:

Febuxostat
Allopurinol

Participants received febuxostat 40 mg or 80 mg for the study depending on their serum uric acid levels were either <6.0 mg/dL or ≥6.0 mg/dL during specified visits. Allopurinol 200 mg to 400 mg (for moderate renal impairment),or 300 mg to 600 mg (for normal and mild renal impairment), increased in 100 mg increments each month until serum uric acid was <6.0 mg/dL was received.

This multi-center trial was conducted in Canada, Mexico and United States. The overall time to participate in this study was approximately 7 years (84 months). Participants made multiple visits to the clinic and were also contacted through the telephone.
Study Started
Apr 23
2010
Primary Completion
May 15
2017
Study Completion
Jul 18
2017
Results Posted
Jun 14
2018
Last Update
Jun 14
2018

Drug Febuxostat

Febuxostat tablets

  • Other names: Uloric, TMX-67

Drug Allopurinol

Allopurinol tablets

  • Other names: Zyloprim, Allohexal, Allosig, Milurit, Alloril, Progout, Zyloric, Puricos, Zyrik 300, Aluron

Febuxostat Experimental

Febuxostat 40 mg (or 80 mg beginning on week 4 if serum uric acid level was ≥6.0 mg/dL), tablets, orally, once daily for up to approximately 82 months.

Allopurinol Active Comparator

Allopurinol 300 mg to 600 mg (increased in 100 mg increments each month until serum uric acid was <6.0 mg/dL), tablets, orally, once daily for up to approximately 83 months to participants with mildly impaired renal function or normal renal function (estimated creatinine clearance [eCLcr] ≥60 mL/min) or allopurinol 200 mg to 400 mg (increased in 100 mg increments each month until serum uric acid was <6.0 mg/dL), tablets, orally, once daily for up to approximately 83 months to participants with moderately impaired renal function (eCLcr ≥30 but <60 mL/min).

Criteria

Inclusion Criteria:

The participant or the participant's legally acceptable representative signs and dates a written, informed consent form/Health Insurance Portability and Accountability Act (HIPAA) Authorization prior to the initiation of any study procedures.
The participant is male ≥50 years of age or female ≥55 years of age and at least 2-years post-menopausal.

The participant has a history of major CV or cerebrovascular disease including at least one of the following:

Myocardial infarction (MI).
Hospitalized unstable angina.
Cardiac or cerebrovascular revascularization procedure.
Stroke.
Hospitalized transient ischemic attack (TIA).
Peripheral vascular disease (ankle brachial index ≤0.6, revascularization and/or well-documented history of claudication).
History of diabetes mellitus with evidence of micro- or macrovascular disease (retinopathy, neuropathy, nephropathy, small vessel vascular diseases).

The participant has a history or presence of gout defined as having one or more of the American Rheumatism Association criteria for the diagnosis of gout:

A tophus proven to contain urate crystals by chemical or polarized light microscopic means, and/or
Characteristic urate crystals in the joint fluid, and/or

History of at least 6 of the following clinical, laboratory, and X-ray phenomena:

More than 1 attack of acute arthritis.
Maximum inflammation developed within 1 day.
Monoarticular arthritis.
Redness observed over joints.
First metatarsophalangeal joint painful or swollen.
Unilateral first metatarsophalangeal joint attack.
Unilateral tarsal joint attack.
Tophus (proven or suspected).
Hyperuricemia.
Asymmetric swelling within a joint on x-ray.
Subcortical cysts without erosions on x-ray.
Joint fluid culture negative for organisms during attack.

The participants must have either:

a serum urate or serum uric acid (sUA) level ≥7.0 mg/dL (≥416 μmol/L) at the Day -7 Visit OR
a sUA level ≥6.0 mg/dL (≥354 μmol/L) at the Day -7 Visit AND inadequately controlled gout (≥1 flare in the 12 months prior to screening and/or the presence of tophi).
The participant is capable of understanding and complying with protocol requirements

Exclusion Criteria:

Participants who meet any of the following criteria will not qualify for entry into this study:

The participant has secondary hyperuricemia (eg, due to myeloproliferative disorder, or organ transplant).
The participant has a history of xanthinuria.
The participant has received urate-lowering therapy (i.e., febuxostat, allopurinol, probenecid, etc.) or excluded medication during the screening period (beginning with Day -7).
The participant has a known hypersensitivity to febuxostat or allopurinol or any components of their formulation.
The participant has active peptic ulcer disease.
The participant has a history of cancer (other than basal cell carcinoma of the skin) within 5 years prior to the first dose of study medication.
The participant had MI or stroke within 60 days prior to the Screening Visit.
The participant has alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) values greater than 2 times the upper limit of normal (×ULN) during the Screening period.
The participant has a significant medical condition and/or conditions that would interfere with the treatment, safety, or compliance with the protocol.
The participant has a history of drug abuse (defined as any illicit drug use) or a history of alcohol abuse within 5 years prior to the Screening Visit or the participant consumes >14 alcoholic beverages per week.
The participant has received any investigational medicinal product within the 30 days prior to the Screening Visit and throughout the study.
The participant's estimated creatinine clearance (CLcr) is <30 mL/min, where CLcr is calculated using the Cockcroft and Gault formula based on ideal body weight (IBW),
The participant is an immediate family member, study site employee, or is in a dependant relationship with a study site employee who is involved in conduct of this study (eg, spouse, parent, child, sibling) or may consent under duress.
The participant is required to take excluded medications
The participant has a known history of infection with hepatitis B, hepatitis C, or human immunodeficiency virus.

Summary

Febuxostat

Allopurinol

All Events

Event Type Organ System Event Term Febuxostat Allopurinol

Percentage of Participants With Primary Major Adverse Cardiovascular Events (MACE) Composite (75% Interim Analysis)

Major adverse cardiovascular events (MACE) were defined as a composite of cardiovascular (CV) death, non-fatal myocardial infarction (MI), nonfatal stroke and unstable angina with urgent coronary revascularization; these events were adjudicated by an independent cardiovascular endpoints committee.

Febuxostat

8.0
percentage of participants

Allopurinol

8.0
percentage of participants

Percentage of Participants With Primary MACE Composite (Final Analysis)

Major adverse cardiovascular events (MACE) were defined as a composite of cardiovascular (CV) death, non-fatal myocardial infarction (MI), nonfatal stroke and unstable angina with urgent coronary revascularization; these events were adjudicated by an independent cardiovascular endpoints committee.

Febuxostat

10.8
percentage of participants

Allopurinol

10.4
percentage of participants

Percentage of Participants With Cardiovascular (CV) Death

Events were adjudicated by an independent cardiovascular endpoints committee as CV death.

Febuxostat

4.3
percentage of participants

Allopurinol

3.2
percentage of participants

Percentage of Participants With Non-fatal Stroke

Events were adjudicated by an independent cardiovascular endpoints committee as non-fatal stroke.

Febuxostat

2.3
percentage of participants

Allopurinol

2.3
percentage of participants

Percentage of Participants With Unstable Angina With Urgent Coronary Revascularization

Events were adjudicated by an independent cardiovascular endpoints committee as unstable angina with urgent coronary revascularization.

Febuxostat

1.6
percentage of participants

Allopurinol

1.8
percentage of participants

Percentage of Participants With Non-fatal Myocardial Infarction (MI)

Events were adjudicated by an independent cardiovascular endpoints committee as non-fatal MI.

Febuxostat

3.6
percentage of participants

Allopurinol

3.8
percentage of participants

Percentage of Participants With Antiplatelet Trialists' Collaborative (APTC) Event

APTC events were defined as a composite of cardiovascular death, nonfatal myocardial infarction, and nonfatal stroke; these events were adjudicated by an independent cardiovascular endpoints committee.

Febuxostat

9.6
percentage of participants

Allopurinol

8.8
percentage of participants

Total

6190
Participants

Age, Continuous

64.8
years (Mean)
Standard Deviation: 8.53

Body Mass Index (BMI)

32.3
kg/m^2 (Median)
Full Range: 17.0 to 75.0

Height

173.0
cm (Mean)
Standard Deviation: 9.65

Weight

100.4
kg (Mean)
Standard Deviation: 22.68

Age, Customized

Alcohol History

BMI Categorical

History of Kidney Stone

Race/Ethnicity, Customized

Region of Enrollment

Renal Function

Sex: Female, Male

Smoking History

Use of any Dose of Aspirin

Use of Clopidogrel and Other Antiplatelet Drugs

Use of Low Dose Aspirin

Use of Nonsteroidal Anti-Inflammatory Drug (NSAIDs)

Overall Study

Febuxostat

Allopurinol

Drop/Withdrawal Reasons

Febuxostat

Allopurinol