Carotene and Retinol Efficacy Trial

Lung Cancer Clinical Trial

— CARET  

Official title:

Caret and Retinol Efficacy Trial: The Caret Coordinating Center

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00712647
• Other study ID #: FHCRC IR-4239A
• Secondary ID: UO1 CA636734239A
• Status: Completed
• Phase: Phase 4
• First received: July 8, 2008
• Last updated: September 25, 2012
• Start date: May 1985
• Est. completion date: June 2005

Study information

• Verified date: September 2012
• Source: Fred Hutchinson Cancer Research Center
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Food and Drug AdministrationUnited States: Fred Hutchinson Cancer Research Center IRB
• Study type: Interventional

Clinical Trial Summary

The Carotene and Retinol Efficacy Trial (CARET) was a randomized, double-blind, placebo-controlled trial of the cancer prevention efficacy and safety of a daily combination of 30 mg of beta-carotene and 25,000 IU of retinyl palmitate in 18,314 persons at high risk for lung cancer. CARET began in 1985, and the intervention was halted in January 1996, 21 months ahead of schedule, with the twin conclusions for definitive evidence of no benefit and substantial evidence of a harmful effect of the intervention on both lung cancer incidence and total mortality. CARET continued to follow and collect endpoints on their participants through 2005. During the active intervention phase of CARET, serum, plasma, whole blood, and lung tissue specimens were collected on participants. These biospecimens make up the CARET Biorepository.

The CARET Biorepository is a valuable resource for population-based studies of the major human cancers. During CARET's twenty years of follow-up (1985-2005), we have received reports of 1,445 participants with lung cancer, 901 with prostate cancer, 433 with breast cancer, 334 with bladder cancer, 332 with colon cancer, and 1,429 with other cancers. CARET is one of the few trials that has prospectively collected serum, plasma, whole blood, blood spots (for DNA), and lung cancer tumor specimens, as well as smoking history and serial food frequency questionnaires (in some individuals for up to 12 years) in populations at high risk for lung cancer. This wealth of information in over 18,000 individuals makes the CARET Biorepository a special resource for cancer researchers.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 18314
• Est. completion date: June 2005
• Est. primary completion date: December 2004
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 45 Years to 69 Years

Eligibility

Inclusion Criteria:

• Asbestos-exposed men who were:

• current smokers or quit within 15 years prior to enrollment

• had first exposure to asbestos on the job at least 15 years prior to enrollment

• had chest X-ray positive for changes compatible with asbestos exposure according to ILO criteria; or had been employed in a protocol-defined high-risk trade for at least 5 years, at least 10 years prior to enrollment.

• Heavy Smokers, men and women:

• cigarette smoking history of 20+ pack-years

• either current smokers or had quit within previous 6 years

Exclusion Criteria:

• Pre-menopausal women

• History or cirrhosis or hepatitis within 12 months prior to enrollment

• Taking > 5500 IU daily vitamin A supplement

• Taking any beta-carotene supplement

• History of cancer within 5 years prior to enrollment

• SGOT > than 2.5X upper limit of normal, or alkaline phosphatase > 1.5X upper limit of normal

• taking less than 50% of study vitamins during the enrollment period between the First and Second Visits.

Study Design

Allocation: Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Lung Cancer

Intervention

Drug:
• Beta Carotene and Retinol
Pilot participants (ppts): Asbestos-Exposed--15 mg/day beta-carotene + 25,000 IU/day retinol Heavy Smokers--30 mg/day beta-carotene + 25,000 IU/day retinol Vanguard & Efficacy ppts: Asbestos-exposed AND heavy smokers--30 mg/day beta-carotene + 25,000 IU/day retinol

Other:
• Placebo
Two placebos, one each/day

Locations

Country	Name	City	State
n/a

Sponsors (2)

Lead Sponsor	Collaborator
Fred Hutchinson Cancer Research Center	National Cancer Institute (NCI)

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Lung Cancer Incidence		bi-annual	Yes
Secondary	Other cancers		bi-annual	Yes