Immune Response to a Therapeutic HIV Vaccine Followed by Treatment Interruption in Patients With Acute or Recent HIV Infection

A Randomized Phase II Study of Therapeutic Immunization and Treatment Interruption Among Subjects Who Began Potent Antiretroviral Therapy Within 30 Days of Diagnosis of Acute or Recent HIV Infection

The purpose of this study is to determine whether the HIV vaccine MRKAd5 HIV-1 gag/pol/nef followed by treatment interruption can increase immune system function in adults with acute or recent HIV infection who have started taking anti-HIV drugs.

Study Overview

Detailed Description

While the advent of highly active antiretroviral therapy (HAART) has contributed to the increasing control of HIV infection and viral replication, ultimate control of HIV infection will require the development of effective HIV-specific immunity in HIV infected individuals. Therapeutic vaccination within the earliest weeks following acute or recent HIV infection may increase the immune system's response to HIV. This study will determine whether MRKAd5 HIV-1 gag/pol/nef vaccine followed by treatment interruption can maintain viral suppression in patients with acute or recent HIV infection.

The interventional part of the study will last 102 weeks. Participants will be randomly assigned to receive either MRKAd5 HIV-1 gag/pol/nef or placebo vaccine at baseline and Weeks 4 and 26. Participants must remain on HAART from study entry until Week 38. Participants whose HIV viral load rebounds two times or more above 500 copies/ml by Weeks 39 to 41 will not enter Step 2 of the study. Participants whose viral load drops to 500 copies/ml or less by Weeks 39 to 41 will enter Step 2, where they will discontinue HAART for 24 weeks. Participants in Step 2 will have plasma HIV viral loads measured every 2 weeks for the first 4 weeks and weekly for the next 3 weeks. Study participants will continue in Step 2 until they experience virologic and immunologic failure or they need to restart HAART for another reason; they will then enter Step 3, where they will reinitiate HAART. Step 3 participants will continue on HAART until Week 102. A long-term safety follow-up period will occur from Weeks 103 to 240.

Timing of the study visits will be determined by which steps a participant enters. A physical exam and blood and urine collection will occur at most study visits throughout the study until Week 102. Follow-up phone calls to study participants will occur every 6 months from Week 102 until Week 240 to collect long-term safety data, including clinical status, CD4 count, and medication history. During the long-term safety follow-up, participants will also have study visits every 6 months. Visits will include medical and medication history.

Study Type

Interventional

Enrollment (Actual)

25

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Surry Hills, American Samoa, 2010
        • 407 Doctors CRS
      • Sydney, Australia, 2010
        • 407 Doctors (Australia) AIEDRP
      • Sydney, Australia, 2010
        • AIDS Research Initiative (Australia) AIEDRP
      • Sydney, Australia, 2010
        • St. Vincent's Hosp. (Australia) AIEDRP
      • Sydney, Australia, 2010
        • Taylor Square Private Clinic (Australia) AIEDRP
      • Sydney, Australia
        • Holdsworth House Gen. Practice (Australia) AIEDRP
    • New South Wales
      • Darlinghurst, New South Wales, Australia, 2010
        • Holdsworth House Medical Practice CRS
      • Darlinghurst, New South Wales, Australia, 2010
        • St. Vincent's Hospital CRS
      • Darlinghurst, New South Wales, Australia, 2010
        • Taylor Square Private Clinic CRS
      • Darlinghurst, New South Wales, Australia
        • AIDS Research Initiative, Darlinghurst CRS
    • California
      • San Diego, California, United States, 92103
        • Ucsd Aiedrp
      • San Francisco, California, United States, 94110
        • Ucsf Aiedrp
      • Torrance, California, United States
        • LA Biomedical Research Institute at Harbor-UCLA AIEDRP
    • Colorado
      • Denver, Colorado, United States, 80220
        • Univ. of Colorado Health Sciences Ctr. AIEDRP
    • Massachusetts
      • Boston, Massachusetts, United States, 02115
        • Fenway Community Health Ctr. CRS
    • Missouri
      • Saint Louis, Missouri, United States, 63110
        • Washington U CRS
    • New York
      • New York, New York, United States, 10003
        • Beth Israel Med. Ctr., ACTU
      • New York, New York, United States, 10016
        • Aaron Diamond AIDS Research Ctr. AIEDRP
    • North Carolina
      • Chapel Hill, North Carolina, United States, 27514
        • Unc Aids Crs
      • Chapel Hill, North Carolina, United States, 27599
        • UNC, Chapel Hill AIEDRP
      • Durham, North Carolina, United States, 27710
        • Duke Univ. Med. Ctr. Adult CRS
      • Durham, North Carolina, United States
        • Dumc Aiedrp
    • Rhode Island
      • Providence, Rhode Island, United States, 02906
        • The Miriam Hosp. ACTG CRS

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 55 years (ADULT)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Initiated HAART within 30 days of an acute or recent HIV-1 infection diagnosis. More information on this criterion can be found in the protocol.
  • Initiated HAART within 30 days of documented acute or recent HIV-1 infection without interruption for more than 7 days
  • Sustained viral suppression, defined as a viral load of 500 copies/mL or less 12 months prior to baseline with an undetectable HIV-1 RNA viral load between 60 to 7 days prior to baseline
  • CD4 count of 450 cells/mm3 or more OR 35% or more between 60 to 14 days prior to baseline
  • Ad5 neutralizing antibody titer of 200 or less at screening
  • Willing to follow all study procedures and schedules
  • Willing to interrupt HAART for at least 24 weeks following completion of the vaccination stage
  • Negative for hepatitis B surface antigen (HBsAg) at screening
  • Willing to use acceptable forms of contraception
  • Infected with HIV-1 subtype B, if this information is available

Exclusion Criteria:

  • Virologic relapse, defined as 2 consecutive measurements of viral load of 500 copies/mL or more at least 7 days apart within 12 months of baseline visit
  • Received more than 7 days of continuous HAART other than that received within 16 days of acute or recent HIV-1 infection. Participants who received HAART as part of post-exposure prophylaxis (PEP) more than 6 months prior to the start of initial HAART may be eligible, provided that they did not acquire HIV-1 infection from the event that required PEP.
  • History of anaphylaxis or allergy to vaccine components, including Tris buffer, magnesium chloride, and polysorbate 80 (Tween)
  • History of clinically significant heart, lung, kidney, liver, pancreatic, gastrointestinal, or neurological disease that, in the opinion of the study investigator, may interfere with the study
  • Contraindication to intramuscular (IM) injection, such as anticoagulant therapy or thrombocytopenia
  • Receipt of any immune globulin or blood products within 3 months prior to baseline
  • Receipt of any live vaccine within 30 days prior to baseline or any inactivated vaccine within 14 days prior to baseline
  • Previous receipt of any HIV vaccine. Participants that were documented to have received only placebo are not excluded.
  • History of any AIDS-defining illness. If a participant's sole AIDS-defining illness is Kaposi's sarcoma limited to the skin and is not anticipated to require systemic chemotherapy, that participant is not excluded.
  • Currently receiving drugs or biologics not approved by the Food and Drug Administration (FDA) other than investigational HIV medications
  • Current or past participation in other studies that might alter the participant's response to the study vaccination
  • Use of any immunomodulatory agents, including but not limited to interleukin-2 (IL-2), granulocyte/macrophage-colony stimulating factor (GM-CSF), and systemic corticosteroids, within 30 days prior to baseline
  • Active alcohol or substance use that, in the investigator's opinion, may interfere with the study
  • Any other criteria or condition that, in the investigator's opinion, may interfere with the study
  • Unwilling or unable to contribute to the planned peripheral blood mononuclear cell (PBMC) blood collection
  • Pregnancy or breastfeeding

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: TREATMENT
  • Allocation: RANDOMIZED
  • Interventional Model: PARALLEL
  • Masking: DOUBLE

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
EXPERIMENTAL: 1
Participants will receive the MRKAd5 HIV-1 gag/pol/nef vaccine at study entry and on Weeks 4 and 26
1.5 x 1010 Ad vg/mL, 1.0 mL administered intramuscularly
PLACEBO_COMPARATOR: 2
Participants will receive the MRKAd5 HIV-1 gag/pol/nef vaccine placebo at study entry and on Weeks 4 and 26
1.0 mL administered intramuscularly

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
Average of log10 HIV-1 RNA viral load
Time Frame: At Weeks 58 and 63
At Weeks 58 and 63
Frequency of Grade 3 or 4 systemic adverse events, the occurrence of a severe or life-threatening injection site adverse event, or death
Time Frame: Throughout study
Throughout study

Secondary Outcome Measures

Outcome Measure
Time Frame
Distribution of plasma HIV RNA viral load
Time Frame: At Weeks 63 and 87
At Weeks 63 and 87
Proportion of patients with controlled viremia and their respective distribution of plasma HIV RNA viral load
Time Frame: At Weeks 63 and 87
At Weeks 63 and 87
Mean viral burden, defined as time-averaged area under the log10 HIV-1 RNA viral load curve
Time Frame: At Weeks 63 and 87
At Weeks 63 and 87
HIV DNA levels
Time Frame: At Weeks 30, 38, 63, and 87
At Weeks 30, 38, 63, and 87
HIV-1 DNA levels
Time Frame: At Weeks 30, 38, 46, 50, 63, and 87
At Weeks 30, 38, 46, 50, 63, and 87
Magnitude and absolute change in CD4 and CD8 counts
Time Frame: At Weeks 63 and 87
At Weeks 63 and 87
Percent and absolute change in the number of HIV-1- specific CD8 cells, as measured by interferon (IFN)-gamma Elispot assay and intracellular cytokine staining
Time Frame: Through Week 30
Through Week 30
Percent and absolute change in the cytokine secretion patterns and the proliferative capacity of HIV-1- specific CD4 and CD8 cells, as measured by multiparameter flow cytometry
Time Frame: Through Week 30
Through Week 30
Breadth and magnitude of HIV-1- specific CD4 and CD8 cell responses
Time Frame: Throughout study
Throughout study
Time to reach the specified virologic or immunologic criteria for reinitiating antiretroviral therapy after treatment interruption
Time Frame: Throughout study
Throughout study
Frequency of Grade 3 or 4 systemic adverse events or the occurrence of a severe or life-threatening injection site adverse event, or HIV-related events, AIDS-defining infections, and death from time of vaccination
Time Frame: Throughout study
Throughout study
Cell-associated infectivity in latently infected cells
Time Frame: At Week 63
At Week 63
Cell-associated infectivity at Week 63 and immunologic responses
Time Frame: At Weeks 63 and 87
At Weeks 63 and 87

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Study Chair: Susan Little, MD, University of California, San Diego AIDS Vaccine Research Center
  • Study Chair: Douglas D. Richman, MD, Departments of Pathology and Medicine, University of California, San Diego

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

March 1, 2006

Primary Completion (ACTUAL)

August 1, 2007

Study Completion (ACTUAL)

October 1, 2010

Study Registration Dates

First Submitted

September 13, 2005

First Submitted That Met QC Criteria

September 13, 2005

First Posted (ESTIMATE)

September 16, 2005

Study Record Updates

Last Update Posted (ACTUAL)

November 1, 2021

Last Update Submitted That Met QC Criteria

October 28, 2021

Last Verified

October 1, 2021

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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