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Pivotal Phase 2b/3 ALVAC/Bivalent gp120/MF59 HIV Vaccine Prevention Safety and Efficacy Study in South Africa

Phase 2
Completed
Conditions
HIV Infections
Interventions
Biological: ALVAC-HIV (vCP2438)
Biological: Placebo
Biological: Bivalent Subtype C gp120/MF59
Registration Number
NCT02968849
Lead Sponsor
National Institute of Allergy and Infectious Diseases (NIAID)
Brief Summary

This study will evaluate the preventive vaccine efficacy, safety, and tolerability of ALVAC-HIV (vCP2438) + Bivalent Subtype C gp120/MF59 in HIV-seronegative South African adults over 24 months and potentially up to 36 months from enrollment.

Detailed Description

This study will evaluate the preventive vaccine efficacy, safety, and tolerability of the ALVAC-HIV vaccine + Bivalent Subtype C gp120 protein adjuvanted with MF59 in HIV-seronegative South African adults over 24 months from enrollment.

Participants will be randomized to receive ALVAC-HIV (vCP2438), or placebo, by intramuscular injection at weeks 0 and 4; they will receive ALVAC-HIV (vCP2438) + Bivalent Subtype C gp120/MF59, or placebo, by IM injection at weeks 12, 24, and 52.

In addition to the vaccination visits, participants will attend study visits at weeks 26, 39, 54, 65, 78, 91, 104, 117, 130, 142, and 156. All study visits, including vaccination visits, will include HIV risk reduction counseling, a physical exam, and an interview/questionnaire. and pregnancy testing for participants capable of becoming pregnant. Select study visits will include a medical history review, physical exam, blood collection, urine collection, HIV testing, and pregnancy testing for participants capable of becoming pregnant.

As of February 3, 2020, vaccinations for this study were suspended. Participants have been asked to continue attending follow-up visits for 12 months after the last vaccination they received. Participants who become HIV infected will be followed for 6 months after diagnosis.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
5404
Inclusion Criteria

Not provided

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Exclusion Criteria

Not provided

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Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
ALVAC-HIV + subtype C gp120/MF59Bivalent Subtype C gp120/MF592700 participants will receive an IM injection of ALVAC-HIV (vCP2438) at months 0 and 1, and an IM injection of ALVAC-HIV (vCP2438) + Bivalent Subtype C gp120/MF59 at months 3, 6, and 12.
ALVAC-HIV + subtype C gp120/MF59ALVAC-HIV (vCP2438)2700 participants will receive an IM injection of ALVAC-HIV (vCP2438) at months 0 and 1, and an IM injection of ALVAC-HIV (vCP2438) + Bivalent Subtype C gp120/MF59 at months 3, 6, and 12.
PlaceboPlacebo2700 participants will receive Sodium Chloride for injection, 0.9% at months 0, 1, 3, 6, and 12.
Primary Outcome Measures
NameTimeMethod
Number of Participants Reporting Local Reactogenicity Signs and Symptoms: Pain and/or TendernessMeasured through 3 full days following each vaccination

Graded according to the Division of AIDS (DAIDS) Table for Grading the Severity of Adult and Pediatric Adverse Events, Version 2.1 \[July 2017\]. The maximum grade observed for each symptom over the time frame is presented.

Number of Participants Reporting Systemic Reactogenicity Signs and SymptomsMeasured through 3 full days following each vaccination

Graded according to the Division of AIDS (DAIDS) Table for Grading the Severity of Adult and Pediatric Adverse Events, Version 2.1 \[July 2017\]. The maximum grade observed for each symptom over the time frame is presented.

Number of Participants Reporting Adverse Events (AEs), by Relationship to Study ProductMeasured through 30 days after each vaccination

For participants reporting multiple AEs over the time frame, the maximum relationship is counted.

Number of Participants With Early Study Termination Associated With an AE or ReactogenicityMeasured through study completion (through 6 months after confirmation of HIV-1 diagnosis for participants who acquired HIV and through 12 months after last vaccination for the rest)

From the termination form, early study termination associated with an AE or reactogenicity reasons are tabulated by treatment group.

Incidence Rate of HIV-1 Infection Diagnosed After Enrollment (Concurrent With First Vaccination) Through 24 Months After EnrollmentMeasured through 24 months after first vaccination

Vaccine efficacy was calculated as 1 minus the hazard ratio for HIV-1 infection, which was estimated using a sex-stratified Cox proportional-hazards (Cox PH) model and tested using a sex-stratified log-rank test. Vaccine efficacy was also measured using a ratio of cumulative incidences (CIR) of HIV-1 infection in the vaccine group as compared with the placebo group, which was calculated using Nelson-Aalen cumulative hazard estimates and tested using a Wald test.

Number of Participants Reporting Local Reactogenicity Signs and Symptoms: Erythema and/or IndurationMeasured through 3 full days following each vaccination

Graded according to the Division of AIDS (DAIDS) Table for Grading the Severity of Adult and Pediatric Adverse Events, Version 2.1 \[July 2017\]. The maximum grade observed for each symptom over the time frame is presented.

Number of Participants Reporting New Chronic Medical ConditionsMeasured through 12 months after last vaccination

A new chronic medical condition is defined as a new onset or exacerbation of medical condition requiring 2 or more visits to a medical provider during a period of at least 30 days.

Number of Participants With Study Product Discontinuation Associated With an AE or ReactogenicityMeasured through study completion (through 6 months after confirmation of HIV-1 diagnosis for participants who acquired HIV and through 12 months after last vaccination for the rest)

From the study product discontinuation form, study product discontinuation reasons are tabulated by treatment group.

Number of Participants Reporting Adverse Events (AEs), by Severity GradeMeasured through 30 days after each vaccination

For participants reporting multiple AEs over the time frame, the maximum severity grade is counted.

Number of Participants Reporting Serious Adverse Events (SAEs)Measured through 12 months after last vaccination

Measured as outlined in Version 2.0 (January 2010) of the Manual for Expedited Reporting of Adverse Events to DAIDS (DAIDS EAE Manual).

Number of Participants Reporting Adverse Events of Special Interest (AESIs)Measured through 12 months after last vaccination

Adverse events of special interest (AESI) were described in Appendix J of the protocol. AESI for this protocol include but are not limited to potential immune-mediated diseases.

Incidence Rate of HIV-1 Infections Diagnosed Following Enrollment and Throughout All Participant Follow-UpMeasured through 36 months after first vaccination

Per the 23 January 2020 DSMB finding that monitoring boundaries for non-efficacy have been met, Primary outcome 1 has been superseded by this primary outcome. Vaccine efficacy was calculated as 1 minus the hazard ratio for HIV-1 infection, which was estimated using a sex-stratified Cox proportional-hazards (Cox PH) model and tested using a sex-stratified log-rank test. Vaccine efficacy was also measured using a ratio of cumulative incidences (CIR) of HIV-1 infection in the vaccine group as compared with the placebo group, which was calculated using Nelson-Aalen cumulative hazard estimates and tested using a Wald test.

Secondary Outcome Measures
NameTimeMethod
Number of Participants With Occurrence of Vaccine-induced IgG3 Binding Antibodies to HIV Proteins at Month 6.5Measured at Month 6.5

Serum IgG3 responses were measured on a Bio-Plex instrument using a standardized custom Luminex assay,run at 1:40 dilution.The readout is background-subtracted mean fluorescent intensity(MFI), with background adjustment for an antigen-specific plate level control.For each sample, response magnitude is net MFI,defined as experimental antigen MFI minus reference antigen MFI.Net MFI lt 1 is set to 1, and net MFI \> 22,000 is set to 22,000.Data are excluded if blood draw date was outside the allowable window,a participant was HIV-infected,reference antigen \> 5,000 MFI or baseline net MFI \> 6,500.Samples from post-enrollment visits have positive responses if they meet three criteria:(1) net MFI greater than or equal to an antigen-specific response threshold (defined as the maximum of 100 and the 95th percentile of baseline net MFI), (2) net MFI values are greater than 3 times baseline net MFI, and (3) experimental antigen MFI values are greater than 3 times baseline M

Level of Vaccine-induced IgG Binding Antibodies to HIV Proteins at Month 6.5Measured at Month 6.5

Serum IgG responses were measured on a Bio-Plex instrument using a standardized custom Luminex assay, run at 1:50 and 1:100 dilutions. The readout is background-subtracted mean fluorescent intensity (MFI), with background adjustment for an antigen-specific plate level control. For each sample, response magnitude is net MFI, defined as experimental antigen MFI minus reference antigen MFI. Net MFI lt 1 is set to 1, and net MFI \> 22,000 is set to 22,000. Data are excluded if blood draw date was outside the allowable window, a participant was HIV-infected, reference antigen \> 5,000 MFI or baseline net MFI \> 6,500. Summary was calculated among positive responders only. The immune response data were also studied for their ability to predict HIV-1 infection through Month 24 (correlates of risk analysis). The comprehensive analysis results are available in Moodie et al 2022 (PubMed ID: 35758878).

Level of Vaccine-induced IgG3 Binding Antibodies to HIV Proteins at Month 6.5Measured at Month 6.5

Serum IgG3 responses were measured on a Bio-Plex instrument using a standardized custom Luminex assay, run at 1:40 dilution. The readout is background-subtracted mean fluorescent intensity (MFI), with background adjustment for an antigen-specific plate level control. For each sample, response magnitude is net MFI, defined as experimental antigen MFI minus reference antigen MFI. Net MFI lt 1 is set to 1, and net MFI \> 22,000 is set to 22,000. Data are excluded if blood draw date was outside the allowable window, a participant was HIV-infected, reference antigen \> 5,000 MFI or baseline net MFI \> 6,500. Summary was calculated among positive responders only. The immune response data were also studied for their ability to predict HIV-1 infection through Month 24 (correlates of risk analysis). The comprehensive analysis results are available in Moodie et al 2022 (PubMed ID: 35758878).

Level of Vaccine-induced IgA Binding Antibodies to HIV Proteins at Month 6.5Measured at Month 6.5

Serum IgA responses were measured on a Bio-Plex instrument using a standardized custom Luminex assay, run at 1:10 dilution. The readout is background-subtracted mean fluorescent intensity (MFI), with background adjustment for an antigen-specific plate level control. For each sample, response magnitude is net MFI, defined as experimental antigen MFI minus reference antigen MFI. Net MFI lt 1 is set to 1, and net MFI \> 22,000 is set to 22,000. Data are excluded if blood draw date was outside the allowable window, a participant was HIV-infected, reference antigen \> 5,000 MFI or baseline net MFI \> 6,500. Summary was calculated among positive responders only. The immune response data were also studied for their ability to predict HIV-1 infection through Month 24 (correlates of risk analysis). The comprehensive analysis results are available in Moodie et al 2022 (PubMed ID: 35758878).

Number of Participants With Viral Sequences at HIV-1 DiagnosisMeasured through 24 months after first vaccination

Number of participants in the female mITT cohort with viral sequences were reported. Viral sequencing was conducted on the earliest available plasma specimens with positive HIV-1 RNA PCR tests from study participants who are diagnosed with HIV-1 infection.

Level of CD4+ and CD8+ T-Cells Expressing IFN-g and/or IL-2 and/or CD40L in Response to HIV Proteins Included in the Vaccine at Month 6.5Measured at Month 6.5

PBMC samples are stimulated with synthetic peptide pools or left unstimulated as negative control. Response magnitude is % cells expressing IFN-g and/or IL-2 after stimulation minus % cells expressing markers after no stimulation. Data are excluded if blood draw date was outside visit window, participant was HIV-infected (post-infection samples), PBMC viability/T-cell count were low or negative control was high. Any Env is the maximum of ZM96 gp120, 1086 gp120, and TV1 gp120. Any HIV is the sum of Any Env and LAI Gag. Negative magnitudes are censored at 0 before calculating sum; if the sum is lt 0.01, it is set to 0.01%. Summary was calculated among positive responders only.

Number of Participants With Occurrence of Vaccine-induced IgA Binding Antibodies to HIV Proteins at Month 6.5Measured at Month 6.5

Serum IgA responses were measured on a Bio-Plex instrument using a standardized custom Luminex assay,run at 1:10 dilution.The readout is background-subtracted mean fluorescent intensity (MFI),with background adjustment for an antigen-specific plate level control.For each sample,response magnitude is net MFI,defined as experimental antigen MFI minus reference antigen MFI.Net MFI lt 1 is set to 1, and net MFI \> 22,000 is set to 22,000.Data are excluded if blood draw date was outside the allowable window,a participant was HIV-infected,reference antigen \> 5,000 MFI or baseline net MFI \> 6,500.Samples from post-enrollment visits have positive responses if they meet three criteria:(1) net MFI greater than or equal to an antigen-specific response threshold (defined as the maximum of 100 and the 95th percentile of baseline net MFI),(2) net MFI values are greater than 3 times baseline net MFI, and (3) experimental antigen MFI values are greater than 3 times baseline MFI.

Incidence Rate of HIV-1 Infection Diagnosed After Enrollment Through 24 Months Among Female ParticipantsMeasured through 24 months after first vaccination

Vaccine efficacy was calculated as 1 minus the hazard ratio for HIV-1 infection, which was estimated using a Cox proportional-hazards (Cox PH) model and tested using a log-rank test.

Incidence Rate of HIV-1 Infection Diagnosed After Enrollment Through 36 Months Post EnrollmentMeasured through 36 months after first vaccination

This outcome measure is the same as Primary Outcome 12, which was added after pre-established criteria for vaccine non-efficacy had been met. Analysis was not repeated but the outcome is listed for completeness.

Number of Participants With Occurrence of CD4+ and CD8+ T-Cells Expressing IFN-g and/or IL-2 in Response to HIV Proteins Included in the Vaccine at Month 6.5Measured at Month 6.5

PBMC samples are stimulated with synthetic peptide pools or left unstimulated as negative control. Response magnitude is % cells expressing IFN-g and/or IL-2 after stimulation minus % cells expressing markers after no stimulation. Contingency table is constructed to assess response: stimulation (peptide/none) vs. marker expression (yes/no). One-sided Fisher's exact test is applied, testing if number of cells positive for the marker is equal in stimulated vs. unstimulated cells. Bonferroni-Holm adjustment is made over peptide pools. Response is positive if adjusted p-value le 0.00001. Data are excluded if blood draw date was outside visit window, participant was HIV-infected (post-infection samples), PBMC viability/T-cell count were low or negative control was high. Any Env is the maximum of ZM96 gp120, 1086 gp120, and TV1 gp120. Any HIV is the sum of Any Env and LAI Gag. Negative magnitudes are censored at 0 before calculating sum; if the sum is lt 0.01, it is set to 0.01%.

Number of Participants With Occurrence of CD4+ and CD8+ T-Cells Expressing IFN-g and/or IL-2 and/or CD40L in Response to HIV Proteins Included in the Vaccine at Month 6.5Measured at Month 6.5

PBMC samples are stimulated with synthetic peptide pools or left unstimulated as negative control. Response magnitude is % cells expressing IFN-g and/or IL-2 after stimulation minus % cells expressing markers after no stimulation. Contingency table is constructed to assess response: stimulation (peptide/none) vs. marker expression (yes/no). One-sided Fisher's exact test is applied, testing if number of cells positive for the marker is equal in stimulated vs. unstimulated cells. Bonferroni-Holm adjustment is made over peptide pools. Response is positive if adjusted p-value le 0.00001. Data are excluded if blood draw date was outside visit window, participant was HIV-infected (post-infection samples), PBMC viability/T-cell count were low or negative control was high. Any Env is the maximum of ZM96 gp120, 1086 gp120, and TV1 gp120. Any HIV is the sum of Any Env and LAI Gag. Negative magnitudes are censored at 0 before calculating sum; if the sum is lt 0.01, it is set to 0.01%.

Level of CD4+ and CD8+ T-Cells Expressing IFN-g and/or IL-2 in Response to HIV Proteins Included in the Vaccine at Month 6.5Measured at Month 6.5

PBMC samples are stimulated with synthetic peptide pools or left unstimulated as negative control. Response magnitude is % cells expressing IFN-g and/or IL-2 after stimulation minus % cells expressing markers after no stimulation. Data are excluded if blood draw date was outside visit window, participant was HIV-infected (post-infection samples), PBMC viability/T-cell count were low or negative control was high. Any Env is the maximum of ZM96 gp120, 1086 gp120, and TV1 gp120. Any HIV is the sum of Any Env and LAI Gag. Negative magnitudes are censored at 0 before calculating sum; if the sum is lt 0.01, it is set to 0.01%. Summary was calculated among positive responders only.

Incidence Rate of HIV-1 Infection Diagnosed After Enrollment Through 24 Months Among Female Participants Aged 25 or YoungerMeasured through 24 months after first vaccination

Vaccine efficacy was calculated as 1 minus the hazard ratio for HIV-1 infection, which was estimated using a Cox proportional-hazards (Cox PH) model and tested using a log-rank test.

Incidence Rate of HIV-1 Infection Diagnosed After Enrollment Through 24 Months Among Female Participants Older Than 25Measured through 24 months after first vaccination

Vaccine efficacy was calculated as 1 minus the hazard ratio for HIV-1 infection, which was estimated using a Cox proportional-hazards (Cox PH) model and tested using a log-rank test.

Incidence Rate of HIV-1 Infection Diagnosed After Enrollment Through Month 24 by Genotypic Characteristics of Viral Sequences From HIV-1 Infected Participants at HIV-1 Diagnosis, Such As Signature Site MutationsMeasured through 24 months after first vaccination

Analysis will only be performed if significant positive evidence of vaccine efficacy from enrollment through 24 months is seen. However, monitoring boundaries for non-efficacy have been met per the 23 January 2020 DSMB finding.

Incidence Rate of HIV-1 Infection Diagnosed After Month 6.5 Through 24 Months Post EnrollmentMeasured after Month 6.5 through 24 months after first vaccination

Vaccine efficacy was calculated as 1 minus the hazard ratio for HIV-1 infection, which was estimated using a sex-stratified Cox proportional-hazards (Cox PH) model and tested using a sex-stratified log-rank test. Vaccine efficacy was also measured using a ratio of cumulative incidences (CIR) of HIV-1 infection in the vaccine group as compared with the placebo group, which was calculated using Nelson-Aalen cumulative hazard estimates and tested using a Wald test.

Number of Participants With Occurrence of Vaccine-induced IgG Binding Antibodies to HIV Proteins at Month 6.5Measured at Month 6.5

Serum IgG responses were measured on a Bio-Plex instrument using a standardized custom Luminex assay, run at 1:50 dilution.The readout is background-subtracted mean fluorescent intensity(MFI),with background adjustment for an antigen-specific plate level control.For each sample,response magnitude is net MFI,defined as experimental antigen MFI minus reference antigen MFI. Net MFI lt 1 is set to 1,and net MFI \> 22,000 is set to 22,000.Data are excluded if blood draw date was outside the allowable window,a participant was HIV-infected,reference antigen \> 5,000 MFI or baseline net MFI \> 6,500.Samples from post-enrollment visits have positive responses if they meet three criteria:(1) net MFI greater than or equal to an antigen-specific response threshold (defined as the maximum of 100 and the 95th percentile of baseline net MFI),(2) net MFI values are greater than 3 times baseline net MFI, and (3) experimental antigen MFI values are greater than 3 times baseline MFI.

Incidence Rate of HIV-1 Infection Diagnosed After Enrollment Through 24 Months Among Male ParticipantsMeasured through 24 months after first vaccination

Vaccine efficacy was calculated as 1 minus the hazard ratio for HIV-1 infection, which was estimated using a Cox proportional-hazards (Cox PH) model and tested using a log-rank test.

Trial Locations

Locations (14)

Emavundleni CRS

🇿🇦

Cape Town, Western Cape, South Africa

Khayelitsha CRS

🇿🇦

Cape Town, Western Cape, South Africa

Kliptown Soweto CRS

🇿🇦

Johannesburg, Gauteng, South Africa

Walter Sisulu University HIV Vaccine Research Unit CRS

🇿🇦

Mthatha, Eastern Cape, South Africa

Aurum Tembisa CRS

🇿🇦

Johannesburg, Gauteng, South Africa

Soweto HVTN CRS

🇿🇦

Johannesburg, Gauteng, South Africa

MeCRU CRS

🇿🇦

Pretoria, Gauteng, South Africa

Setshaba Research Centre CRS

🇿🇦

Soshanguve, Gauteng, South Africa

eThekwini CRS

🇿🇦

Durban, Kwa Zulu Natal, South Africa

Isipingo CRS

🇿🇦

Isipingo, Kwa Zulu Natal, South Africa

Qhakaza Mbokodo Research Clinic CRS

🇿🇦

Ladysmith, Kwa Zulu Natal, South Africa

Verulam CRS

🇿🇦

Verulam, Kwa Zulu Natal, South Africa

Aurum Institute Klerksdorp CRS

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Klerksdorp, North West Province, South Africa

Rustenburg CRS

🇿🇦

Rustenburg, North West Province, South Africa

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