Safety, Tolerability and Immune Response to LC002, an Experimental Therapeutic Vaccine, in Adults Receiving HAART

National Institute of Allergy and Infectious Diseases (NIAID)28 enrolled

Overview

LC002 is an experimental therapeutic vaccine designed to boost the immune response of people infected with HIV. The purpose of this study was to determine the safety and tolerability of and immune response to LC002 in HIV-1-infected adults who are currently receiving anti-HIV treatment.

The use of highly active antiretroviral therapy (HAART) has dramatically improved the rates of survival, morbidity, and mortality among HIV-infected people throughout the world. However, the costs, long-term toxicity, and problems with adherence associated with HAART regimens make such treatment plans less than optimal for individuals seeking treatment for HIV infection. Also, because viral reservoirs cannot be eradicated, HIV-infected people must usually be on HAART indefinitely in order to keep their infection under control. While the mechanism is still unclear, the immune system weakens as HIV disease progresses. A therapeutic HIV vaccine given to HIV infected people may help to promote better immune responses. LC002 is a novel HIV therapeutic vaccine containing a DNA plasmid that codes for most of HIV-1's proteins. LC002 is a unique vaccine in that it is given through topical administration; this allows for Langerhans cells (immune cells located under the surface of the skin) to pick up the vaccine and deliver it to the lymph nodes, causing an immune reaction. This study evaluated the safety, tolerability, and immunogenicity of LC002 in HIV-infected adults currently receiving HAART. There were three cohorts in this study which were enrolled sequentially. Participants in a given cohort were randomly assigned to receive either LC002 (6 participants) or placebo (2 participants). * In Cohort 1, participants received three separate low-dose vaccinations of LC002 (Arm A: 0.1 mg DNA/participant, 0.8 ml total, administered over two skin sites of 80 cm\^2 each, 0.4 ml/site) or 3 separate vaccinations of placebo (Arm B: 0.8 ml total, administered over two skin sites of 80 cm\^2 each, 0.4 ml/site). Vaccinations were given over two skin sites on the left and right upper back. Participants received vaccinations at weeks 1, 7, and 13. * In Cohort 2, participants received three separate high-dose vaccinations of LC002 (Arm C: 0.4 mg DNA/participant, 3.2 ml total, administered over four skin sites of 80 cm\^2 each, 0.8 ml/site) or three separate vaccinations of placebo (Arm D: 3.2 ml total, administered over four skin sites of 80 cm\^2 each, 0.8 ml/site). Vaccinations were given over four skin sites on the left and right upper back and left and right upper ventral thigh. Participants received vaccinations at weeks 1, 7, and 13. * In Cohort 3, participants received six separate high-dose vaccinations of LC002 (Arm E: 0.4 mg DNA/participant, 3.2 ml total, administered over four skin sites of 80 cm\^2 each, 0.8 ml/site) or six vaccinations of placebo (Arm F: 3.2 ml total, administered over four skin sites of 80 cm\^2 each, 0.8 ml/site). Vaccinations were given over four skin sites on the left and right upper back and left and right upper ventral thigh. Participants received vaccinations at study entry and weeks 1, 6, 7, 12, and 13. The decision to open the next cohort was made when all participants in the current cohort have remained on study for \>=14 days after the second vaccination or prematurely discontinued from study or had a primary safety endpoint (see primary outcome measure definition). Dose escalation required no primary safety endpoint and on-study follow-up for \>=6 participants in the previous cohort(s). Prior to receiving the vaccine, the chosen vaccine administration site on the back or thigh was disinfected and exfoliated. A skin patch was applied to the site, and the vaccine solution was placed on the skin underneath the patch with a needleless syringe. Participants were allowed to remove the skin patch 3 hours post vaccination. For the first and second vaccinations, participants were required to remain at the clinic for 3 hours post-vaccination so study staff can assess for side effects. If no side effects occurred after the first two vaccinations, participants were required to stay at the clinic for only 30 minutes after receiving later vaccinations. At the start of the study, participants were asked to keep a diary and record daily any side effects or skin irritation they may have experienced following vaccination. Participants were required to bring their diaries with them to their next clinic visit. Two days after vaccination, participants were followed-up by phone and were asked about any side effects they may have experienced. Participants who experienced side effects were asked to return to the clinic for examination. There were 13 study visits; they occurred at study entry and Weeks 1, 3, 6, 7, 9, 12, 13, 15, 17, 24, 37, and 61. Study visits included medication history, a physical exam, and collection of diaries. Blood and urine collection occurred at selected visits. HAART was not be provided by the study.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Enrollment

Conditions

HIV Infections

Interventions

LC002 standard vaccinationBIOLOGICAL

0.1 mg DNA/participant, 0.8 ml total administered subcutaneously

LC002 high-dose vaccinationBIOLOGICAL

0.4 mg DNA/participant, 3.2 ml total administered subcutaneously

LC002 placebo vaccinationBIOLOGICAL

Placebo vaccination administered subcutaneously

Eligibility

Sex: ALLMin age: 18 YearsMax age: 50 Years

Medical Language ↔ Plain English

Inclusion Criteria: * HIV-1-infected * On a stable HAART regimen without changes or interruptions for more than 4 consecutive days for at least 12 weeks prior to study entry. Patients must be currently taking regimens containing drugs of at least two different classes. * Two readings of plasma HIV-1 viral load of less than 50 copies/ml within 30 days prior to study entry. More information on this criterion can be found in the protocol. * CD4 count greater than 350 cells/mm\^3 within 12 weeks prior to study entry * Lowest CD4 count greater than 250 cells/mm\^3 at any time prior to study entry * Willing to use acceptable forms of contraception * Karnofsky performance score 90 or higher obtained within 30 days prior to study entry Exclusion Criteria: * HIV-1 viral load greater than 500 copies/ml within the 24 weeks prior to study entry * History of or current active skin disease (e.g., atopic dermatitis, psoriasis) or any chronic autoimmune disease (e.g., Graves' disease). Participants with minor, localized skin conditions that, in the opinion of the investigator, do not represent a safety concern, are not excluded. * Treatment with topical corticosteroids at the proposed vaccination sites (Cohort 1: left and right upper back; Cohorts 2 and 3: left and right upper back and left and right upper ventral thigh) within 2 weeks of study entry * Excessive exposure to the sun (e.g., sunbathing, tanning bed) within 2 weeks prior to study entry * Laser hair removal within 2 weeks prior to study entry * Use of any local skin treatments (e.g., topical/chemical hair removal, ointments, possible irritants) to the targeted vaccination sites within 7 days prior to study entry * History of diabetes or bleeding disorders * Previous CDC Category C event. More information on this criterion can be found in the protocol. * Use of immunomodulating therapy, including cyclosporine, IgG-containing products, interleukins, interferons, or systemic glucocorticosteroids (including those inhaled) within 6 months prior to study entry * Exposure to an experimental HIV vaccine within 6 months prior to study entry * Any vaccine within 30 days prior to study entry * Investigational products within 12 weeks prior to study entry * Allergy or sensitivity to study vaccine products, adhesives, or polyester * Current drug or alcohol use or dependence that, in the opinion of the investigator, would interfere with the study * Serious illness requiring systemic treatment and/or hospitalization. Participants who complete therapy or are clinically stable on therapy for at least 14 days prior to study entry are not excluded. * Positive hepatitis B surface antigen or positive anti-hepatitis C antibody at screening * History of treatment with HAART during primary infection * History of lymph node irradiation * Pregnant or breastfeeding * Certain abnormal laboratory results. More information on this criterion can be found in the protocol

Locations (5)

Univ. of California Davis Med. Ctr., ACTU

Sacramento, California, United States

Chicago Children's CRS

Chicago, Illinois, United States

Case CRS

Cleveland, Ohio, United States

MetroHealth CRS

Cleveland, Ohio, United States

Outcomes

Primary Outcomes

Percent of Participants With Primary Safety Endpoint

Primary safety endpoint is defined as occurrence of at least one grade 3 or higher adverse event, including signs/symptoms, lab toxicities, and/or clinical events that is possibly or definitely related to study treatment. Event's relationship to the study treatment was determined by the protocol core team, including site clinicians on the team, blinded to the treatment arm. Adverse events solely attributed to an allergic reaction to the adhesive of the tape used to adhere the vaccination patch to the skin and not the vaccine itself were not used in determination of the primary safety endpoint.

Time frame: From start of study vaccination to 28 days after the last study vaccination

Secondary Outcomes

Time-averaged Area Under the Curve (AUC) of CD4+ T-cell Count in PBMCs

Area under the curve (AUC) using linear trapezoidal method, of CD4+ T-cell count responses was used to characterize each participant's overall CD4+ count response. Each AUC was divided by 61 weeks to have the same unit as the raw data.

Time frame: From start of study vaccination to week 61

Time-averaged AUC of CD8+ T-cell Count in PBMCs

Area under the curve (AUC) using linear trapezoidal method, of CD8+ T-cell count responses was used to characterize each participant's overall CD8+ count response. Each AUC was divided by 61 weeks to have the same unit as the raw data.

Time frame: From start of study vaccination to week 61

Time-averaged AUC of the Magnitude of HIV-specific Immune Response, as Determined by Taking the Mean of the Number of Spot-forming Cells/10^6 PBMCs Observed in Each PHPC Assay for IFN-gamma Production for Gag p17, Gag p24, Gag p15 and Tat/Rev.

At each week, the mean spot-forming cells/10\^6 PBMCs detected by the PHPC (precursors with high proliferative capacity) assay across gag p17, gag p24, gag p15 and tat/rev was obtained per participant. Area under the curve (AUC) using linear trapezoidal method was used to characterize each participant's overall response. Each AUC was divided by 37 weeks to have the same unit of measure as the raw data.

Data from ClinicalTrials.gov

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University of Pittsburgh CRS

Pittsburgh, Pennsylvania, United States

Time frame: From start of study vaccination to week 37

Time-averaged AUC of the Magnitude of HIV-specific Immune Response, as Determined by the Number of Spot-forming Cells/10^6 PBMCs Observed in Each PHPC Assay for IFN-gamma Production for Gag p17, Gag p24, Gag p15 and Tat/Rev.

Area under the curve (AUC) using linear trapezoidal method for each antigen was used to characterize each participant's overall response to the antigen as detected by the PHPC assay. Each AUC was divided by 37 weeks to have the same unit of measure as the raw data.

Time frame: From start of study vaccination to week 37

Time-averaged AUC of the Magnitude of HIV-specific Immune Response, as Determined by Taking the Mean of the Number of Spot-forming Cells/10^6 PBMCs Observed in Each ELISPOT Assay for IFN-gamma Production for Gag p17, Gag p24, Gag p15 and Tat/Rev.

At each week, the mean spot-forming cells/10\^6 PBMCs across gag p17, gag p24, gag 15 and tat/rev was obtained per participant. Area under the curve (AUC) using linear trapezoidal method was used to characterize each participant's overall response. Each AUC was divided by 37 weeks to have the same unit of measure as the raw data.

Time frame: From start of study vaccination to week 37

Time-averaged AUC of the Magnitude of HIV-specific Immune Response, as Determined by the Number of Spot-forming Cells/10^6 PBMCs Observed in Each ELISPOT Assay for IFN-gamma Production for Gag p17, Gag p24, Gag p15 and Tat/Rev.

Area under the curve (AUC) using linear trapezoidal method for each antigen was used to characterize each participant's overall response to the antigen. Each AUC was divided by 37 weeks to have the same unit of measure as the raw data.

Time frame: From start of study vaccination to week 37

Anti-dsDNA Antibody Response

Results report the number of participants who had negative anti-dsDNA antibody result at baseline and at week 17 or 61.

Time frame: From start of study vaccination to week 61

Time-averaged AUC of T-cell Count of HIV-1-specific CD4+ T-cell Subsets, Based on Flow Cytometry With CFSE Staining to Detect Antigen-specific Lymphocyte Proliferation Responding to p24 Protein, Gag/Pol/Env and Tat/Rev

Area under the curve (AUC) using linear trapezoidal method was used to characterize each participant's overall response. Each AUC was divided by 24 weeks to have the same unit of measure as the raw data.