MedPath

Zidovudine and Lamivudine Given Once Versus Twice Daily

Phase 1
Completed
Conditions
HIV Infections
Registration Number
NCT00014014
Lead Sponsor
National Institute of Allergy and Infectious Diseases (NIAID)
Brief Summary

The purpose of this study is to see if the full daily dose of Combivir (zidovudine \[ZDV\]/lamivudine \[3TC\]) taken once a day is as effective as the usual recommended twice-a-day dose.

Studies have shown that the antiviral activity of ZDV can continue in the body even after there does not appear to be any ZDV left in the blood. This occurs because the body breaks down the drug into substances that remain active against HIV. The body also breaks down 3TC, a drug that is combined with ZDV in the Combivir product, in a similar way. Since antiviral activity may continue after Combivir is removed from the body, it may not be necessary to take the drug as often as once thought. This study carefully measures levels of the active substances in order to find out whether the same amount of antiviral activity occurs with less-frequent dosing.

Detailed Description

Initial dosing regimens of ZDV were based on the plasma half-life of the drug. However, recent studies of the intracellular metabolism of ZDV have demonstrated that the active anabolite, ZDV-TP, is present within the cell for an extended period of time relative to the drug in the plasma. This suggests that antiviral activity may be present for a sufficient time frame with less-frequent dosing of the drug. Careful comparison of the rate and extent of intracellular phosphorylated ZDV metabolites as a function of schedule will determine whether less-frequent dosing has a sound pharmacological basis. Also, the intracellular metabolism of 3TC is via different enzymes than that of ZDV and there are quantitative differences in the amount of triphosphate formed from both drugs. This study will provide information about intracellular metabolites when both ZDV and 3TC are concurrently administered.

This is a study of 2 schedules of Combivir therapy. At study entry or Part I, all patients take Combivir twice daily for the 7-day adherence assessment. Patients who have demonstrated 70 percent or greater adherence \[AS PER AMENDMENT 7/20/01: 70 percent compliance with the study regimen for Combivir. This corresponds to taking at least 10 of the prescribed 14 Combivir tablets during the 7 days prior to an adherence assessment, including all scheduled doses in the 24-hour period prior to that assessment.\], and have taken all scheduled Combivir doses in the previous 24 hours, have pharmacokinetic samples obtained and are randomized to Group A or Group B in Part II. Group A patients take 2 Combivir tablets once daily; Group B patients take 1 Combivir tablet twice daily. After patients have completed the targeted duration of Part II (7 days for Group A and 7-14 days for Group B), they are assessed for adherence. Patients who have demonstrated 70 percent or greater adherence, and have taken all scheduled Combivir doses in the previous 24 hours, have pharmacokinetic samples obtained and then change to the alternate dosing schedule. Group A patients take 1 Combivir tablet twice daily; Group B patients take 2 Combivir tablets once daily. After patients have completed the targeted duration of Part III (7-14 days for Group A and 7 days for Group B), they are assessed for adherence. All patients who meet the adherence criteria have pharmacokinetic samples obtained. After completion of Part III pharmacokinetic studies, patients have completed the study. (Note: Combivir will not be provided in this study.)

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
20
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Primary Outcome Measures
NameTimeMethod
Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (20)

State Univ of New York at Stony Brook

🇺🇸

Stony Brook, New York, United States

Temple University School of Medicine

🇺🇸

Philadelphia, Pennsylvania, United States

Univ of Mississippi Med Ctr

🇺🇸

Jackson, Mississippi, United States

Univ of Medicine & Dentistry of New Jersey / Univ Hosp

🇺🇸

Newark, New Jersey, United States

Tulane Univ / Charity Hosp of New Orleans

🇺🇸

New Orleans, Louisiana, United States

Univ of Puerto Rico / Univ Children's Hosp AIDS

🇵🇷

San Juan, Puerto Rico

Saint Jude Children's Research Hosp of Memphis

🇺🇸

Memphis, Tennessee, United States

Texas Children's Hosp / Baylor Univ

🇺🇸

Houston, Texas, United States

Univ of California, San Diego

🇺🇸

San Diego, California, United States

Children's Hosp of Boston

🇺🇸

Boston, Massachusetts, United States

Los Angeles County - USC Med Ctr

🇺🇸

Los Angeles, California, United States

Emory Univ Hosp / Pediatrics

🇺🇸

Atlanta, Georgia, United States

Univ of Florida Health Science Ctr / Pediatrics

🇺🇸

Jacksonville, Florida, United States

Mt Sinai Hosp Med Ctr / Dept of Pediatrics

🇺🇸

Chicago, Illinois, United States

Metropolitan Hosp Ctr

🇺🇸

New York, New York, United States

Chicago Children's Memorial Hosp

🇺🇸

Chicago, Illinois, United States

Children's Hosp of Philadelphia

🇺🇸

Philadelphia, Pennsylvania, United States

Cook County Hosp

🇺🇸

Chicago, Illinois, United States

SUNY Health Sciences Ctr at Syracuse / Pediatrics

🇺🇸

Syracuse, New York, United States

St Joseph's Hosp & Med Center

🇺🇸

Paterson, New Jersey, United States

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