Safety and Immunogenicity of a DNA Vaccine With Subtype C gp120 Protein Adjuvanted With MF59 or AS01B: A Phase 1/2a HIV-1 Vaccine Trial.

BACKGROUND: An effective vaccine is required to end the HIV pandemic. We evaluated the safety and immunogenicity of a DNA (DNA-HIV-PT123) vaccine with low- or high-dose bivalent (TV1.C and 1086.C glycoprotein 120) subtype C envelope protein combinations, adjuvanted with MF59 or AS01B. METHODS: HIV Vaccine Trials Network (HVTN)108 was a randomized, placebo-controlled, double-blind, phase 1/2a trial conducted in the United States and South Africa. HIV-negative adults were randomly assigned to 1 of 7 intervention arms or placebo to assess DNA prime with DNA/protein/adjuvant boosts, DNA/protein/adjuvant co-administration, and low-dose protein/adjuvant regimens. HVTN111 trial participants who received an identical regimen were also included. Outcomes included safety and immunogenicity 2 weeks and 6 months after final vaccination. RESULTS: From June 2016 to July 2018, 400 participants were enrolled (N = 334 HVTN108, N = 66 HVTN111); 370 received vaccine and 30 received placebo. There were 48 grade 3 and 3 grade 4 reactogenicity events among 39/400 (9.8%) participants, and 32 mild/moderate-related adverse events in 23/400 (5.8%) participants. All intervention groups demonstrated high IgG response rates (>89%) and high magnitudes to HIV-1 Env gp120 and gp140 proteins; response rates for AS01B-adjuvanted groups approached 100%. V1V2 IgG magnitude, Fc-mediated functions, IgG3 Env response rates, and CD4+ T-cell response magnitudes and rates were higher in the AS01B-adjuvanted groups. The AS01B-adjuvanted low-dose protein elicited greater IgG responses than the higher protein dose. CONCLUSIONS: The vaccine regimens were generally well tolerated. Co-administration of DNA with AS01B-adjuvanted bivalent Env gp120 elicited the strongest humoral responses; AS01B-adjuvanted regimens elicited stronger CD4+ T-cell responses, justifying further evaluation.ClinicalTrials.gov registration: NCT02915016, registered 26 September 2016.

Safety and immunogenicity of a subtype C ALVAC-HIV (vCP2438) vaccine prime plus bivalent subtype C gp120 vaccine boost adjuvanted with MF59 or alum in healthy adults without HIV (HVTN 107): A phase 1/2a randomized trial.

BACKGROUND: Adjuvants are widely used to enhance and/or direct vaccine-induced immune responses yet rarely evaluated head-to-head. Our trial directly compared immune responses elicited by MF59 versus alum adjuvants in the RV144-like HIV vaccine regimen modified for the Southern African region. The RV144 trial of a recombinant canarypox vaccine vector expressing HIV env subtype B (ALVAC-HIV) prime followed by ALVAC-HIV plus a bivalent gp120 protein vaccine boost adjuvanted with alum is the only trial to have shown modest HIV vaccine efficacy. Data generated after RV144 suggested that use of MF59 adjuvant might allow lower protein doses to be used while maintaining robust immune responses. We evaluated safety and immunogenicity of an HIV recombinant canarypox vaccine vector expressing HIV env subtype C (ALVAC-HIV) prime followed by ALVAC-HIV plus a bivalent gp120 protein vaccine boost (gp120) adjuvanted with alum (ALVAC-HIV+gp120/alum) or MF59 (ALVAC-HIV+gp120/MF59) or unadjuvanted (ALVAC-HIV+gp120/no-adjuvant) and a regimen where ALVAC-HIV+gp120 adjuvanted with MF59 was used for the prime and boost (ALVAC-HIV+gp120/MF59 coadministration). METHODS AND FINDINGS: Between June 19, 2017 and June 14, 2018, 132 healthy adults without HIV in South Africa, Zimbabwe, and Mozambique were randomized to receive intramuscularly: (1) 2 priming doses of ALVAC-HIV (months 0 and 1) followed by 3 booster doses of ALVAC-HIV+gp120/MF59 (months 3, 6, and 12), n = 36; (2) 2 priming doses of ALVAC-HIV (months 0 and 1) followed by 3 booster doses of ALVAC-HIV+gp120/alum (months 3, 6, and 12), n = 36; (3) 4 doses of ALVAC-HIV+gp120/MF59 coadministered (months 0, 1, 6, and 12), n = 36; or (4) 2 priming doses of ALVAC-HIV (months 0 and 1) followed by 3 booster doses of ALVAC-HIV+gp120/no adjuvant (months 3, 6, and 12), n = 24. Primary outcomes were safety and occurrence and mean fluorescence intensity (MFI) of vaccine-induced gp120-specific IgG and IgA binding antibodies at month 6.5. All vaccinations were safe and well-tolerated; increased alanine aminotransferase was the most frequent related adverse event, occurring in 2 (1.5%) participants (1 severe, 1 mild). At month 6.5, vaccine-specific gp120 IgG binding antibodies were detected in 100% of vaccinees for all 4 vaccine groups. No significant differences were seen in the occurrence and net MFI of vaccine-specific IgA responses between the ALVAC-HIV+gp120/MF59-prime-boost and ALVAC-HIV+gp120/alum-prime-boost groups or between the ALVAC-HIV+gp120/MF59-prime-boost and ALVAC-HIV+gp120/MF59 coadministration groups. Limitations were the relatively small sample size per group and lack of evaluation of higher gp120 doses. CONCLUSIONS: Although MF59 was expected to enhance immune responses, alum induced similar responses to MF59, suggesting that the choice between these adjuvants may not be critical for the ALVAC+gp120 regimen. TRIAL REGISTRATION: HVTN 107 was registered with the South African National Clinical Trials Registry (DOH-27-0715-4894) and ClinicalTrials.gov (NCT03284710).

Protein dose-sparing effect of AS01B adjuvant in a randomized preventive HIV vaccine trial of ALVAC-HIV (vCP2438) and adjuvanted bivalent subtype C gp120.

BACKGROUND: HVTN 120 is a phase 1/2a randomized double-blind placebo-controlled HIV vaccine trial that evaluated the safety and immunogenicity of ALVAC-HIV (vCP2438) and MF59- or AS01B-adjuvanted bivalent subtype C gp120 Env protein at two dose levels in healthy HIV-uninfected adults. Trial registration URL https://clinicaltrials.gov/ct2/show/NCT03122223 and registration number NCT03122223. METHODS: Participants received ALVAC-HIV (vCP2438) alone or placebo at months 0 and 1. At months 3 and 6, participants received either placebo, ALVAC-HIV (vCP2438) with 200µg of bivalent subtype C gp120 adjuvanted with MF59 or AS01B, or ALVAC-HIV (vCP2438) with 40µg of bivalent subtype C gp120 adjuvanted with AS01B. Primary outcomes were safety and immune responses. RESULTS: We enrolled 160 participants, 55% females, 18-40 years old (median age 24 years) of whom 150 received vaccine and 10 placebo. Vaccines were generally safe and well tolerated. At months 6.5 and 12, CD4+ T-cell response rates and magnitudes were higher in the AS01B-adjuvanted groups than in the MF59-adjuvanted group. At month 12, HIV-specific Env-gp120 binding antibody response magnitudes in the 40µg gp120/AS01B group were higher than in either of the 200µg gp120 groups. CONCLUSIONS: The 40µg dose gp120/AS01B regimen elicited the highest CD4+ T-cell and binding antibody responses.

Phase 1 Human Immunodeficiency Virus (HIV) Vaccine Trial to Evaluate the Safety and Immunogenicity of HIV Subtype C DNA and MF59-Adjuvanted Subtype C Envelope Protein.

BACKGROUND: The Pox-Protein Public-Private Partnership is performing a suite of trials to evaluate the bivalent subtype C envelope protein (TV1.C and 1086.C glycoprotein 120) vaccine in the context of different adjuvants and priming agents for human immunodeficiency virus (HIV) type 1 (HIV-1) prevention. METHODS: In the HIV Vaccine Trials Network 111 trial, we compared the safety and immunogenicity of DNA prime followed by DNA/protein boost with DNA/protein coadministration injected intramuscularly via either needle/syringe or a needle-free injection device (Biojector). One hundred thirty-two healthy, HIV-1-uninfected adults were enrolled from Zambia, South Africa, and Tanzania and were randomized to 1 of 6 arms: DNA prime, protein boost by needle/syringe; DNA and protein coadministration by needle/syringe; placebo by needle/syringe; DNA prime, protein boost with DNA given by Biojector; DNA and protein coadministration with DNA given by Biojector; and placebo by Biojector. RESULTS: All vaccinations were safe and well tolerated. DNA and protein coadministration was associated with increased HIV-1 V1/V2 antibody response rate, a known correlate of decreased HIV-1 infection risk. DNA administration by Biojector elicited significantly higher CD4+ T-cell response rates to HIV envelope protein than administration by needle/syringe in the prime/boost regimen (85.7% vs 55.6%; P = .02), but not in the coadministration regimen (43.3% vs 48.3%; P = .61). CONCLUSIONS: Both the prime/boost and coadministration regimens are safe and may be promising for advancement into efficacy trials depending on whether cellular or humoral responses are desired. CLINICAL TRIALS REGISTRATION: South African National Clinical Trials Registry (application 3947; Department of Health [DoH] no. DOH-27-0715-4917) and ClinicalTrials.gov (NCT02997969).

Safety and immune responses after a 12-month booster in healthy HIV-uninfected adults in HVTN 100 in South Africa: A randomized double-blind placebo-controlled trial of ALVAC-HIV (vCP2438) and bivalent subtype C gp120/MF59 vaccines.

BACKGROUND: HVTN 100 evaluated the safety and immunogenicity of an HIV subtype C pox-protein vaccine regimen, investigating a 12-month booster to extend vaccine-induced immune responses. METHODS AND FINDINGS: A phase 1-2 randomized double-blind placebo-controlled trial enrolled 252 participants (210 vaccine/42 placebo; median age 23 years; 43% female) between 9 February 2015 and 26 May 2015. Vaccine recipients received ALVAC-HIV (vCP2438) alone at months 0 and 1 and with bivalent subtype C gp120/MF59 at months 3, 6, and 12. Antibody (IgG, IgG3 binding, and neutralizing) and CD4+ T-cell (expressing interferon-gamma, interleukin-2, and CD40 ligand) responses were evaluated at month 6.5 for all participants and at months 12, 12.5, and 18 for a randomly selected subset. The primary analysis compared IgG binding antibody (bAb) responses and CD4+ T-cell responses to 3 vaccine-matched antigens at peak (month 6.5 versus 12.5) and durability (month 12 versus 18) timepoints; IgG responses to CaseA2_gp70_V1V2.B, a primary correlate of risk in RV144, were also compared at these same timepoints. Secondary and exploratory analyses compared IgG3 bAb responses, IgG bAb breadth scores, neutralizing antibody (nAb) responses, antibody-dependent cellular phagocytosis, CD4+ polyfunctionality responses, and CD4+ memory sub-population responses at the same timepoints. Vaccines were generally safe and well tolerated. During the study, there were 2 deaths (both in the vaccine group and both unrelated to study products). Ten participants became HIV-infected during the trial, 7% (3/42) of placebo recipients and 3% (7/210) of vaccine recipients. All 8 serious adverse events were unrelated to study products. Less waning of immune responses was seen after the fifth vaccination than after the fourth, with higher antibody and cellular response rates at month 18 than at month 12: IgG bAb response rates to 1086.C V1V2, 21.0% versus 9.7% (difference = 11.3%, 95% CI = 0.6%-22.0%, P = 0.039), and ZM96.C V1V2, 21.0% versus 6.5% (difference = 14.5%, 95% CI = 4.1%-24.9%, P = 0.004). IgG bAb response rates to all 4 primary V1V2 antigens were higher 2 weeks after the fifth vaccination than 2 weeks after the fourth vaccination: 87.7% versus 75.4% (difference = 12.3%, 95% CI = 1.7%-22.9%, P = 0.022) for 1086.C V1V2, 86.0% versus 63.2% (difference = 22.8%, 95% CI = 9.1%-36.5%, P = 0.001) for TV1c8.2.C V1V2, 67.7% versus 44.6% (difference = 23.1%, 95% CI = 10.4%-35.7%, P < 0.001) for ZM96.C V1V2, and 81.5% versus 60.0% (difference = 21.5%, 95% CI = 7.6%-35.5%, P = 0.002) for CaseA2_gp70_V1V2.B. IgG bAb response rates to the 3 primary vaccine-matched gp120 antigens were all above 90% at both peak timepoints, with no significant differences seen, except a higher response rate to ZM96.C gp120 at month 18 versus month 12: 64.5% versus 1.6% (difference = 62.9%, 95% CI = 49.3%-76.5%, P < 0.001). CD4+ T-cell response rates were higher at month 18 than month 12 for all 3 primary vaccine-matched antigens: 47.3% versus 29.1% (difference = 18.2%, 95% CI = 2.9%-33.4%, P = 0.021) for 1086.C, 61.8% versus 38.2% (difference = 23.6%, 95% CI = 9.5%-37.8%, P = 0.001) for TV1.C, and 63.6% versus 41.8% (difference = 21.8%, 95% CI = 5.1%-38.5%, P = 0.007) for ZM96.C, with no significant differences seen at the peak timepoints. Limitations were that higher doses of gp120 were not evaluated, this study was not designed to investigate HIV prevention efficacy, and the clinical significance of the observed immunological effects is uncertain. CONCLUSIONS: In this study, a 12-month booster of subtype C pox-protein vaccines restored immune responses, and slowed response decay compared to the 6-month vaccination. TRIAL REGISTRATION: ClinicalTrials.gov NCT02404311. South African National Clinical Trials Registry (SANCTR number: DOH--27-0215-4796).

Persistence of vaccine-elicited immune response up to 14 years post-HIV gp120-NefTat/AS01B vaccination.

BACKGROUND: Vaccines eliciting protective and persistent immune responses against multiple human immunodeficiency virus type 1 (HIV-1) clades are needed. This study evaluated the persistence of immune responses induced by an investigational, AS01-adjuvanted HIV-1 vaccine as long as 14 years after vaccination. METHODS: This phase I, open-label, descriptive, mono-centric, extension study with a single group (NCT03368053) was conducted in adults who received ≥3 doses of the clade B gp120-NefTat/AS01B vaccine candidate 14 years earlier in a previous clinical trial (NCT00434512). Binding responses of serum antibodies targeting a panel of envelope glycoproteins, including gp120, gp140 and V1V2-scaffold antigens and representative of the antigenic diversity of HIV-1, were measured by binding antibody multiplex assay (BAMA). The gp120-specific CD4+/CD8+ T-cell responses were assessed by intracellular cytokine staining assay. RESULTS: At Year 14, positive IgG binding antibody responses were detected in 15 out of the 16 antigens from the BAMA V1V2 breadth panel, with positive response rates ranging from 7.1% to 60.7%. The highest response rates were observed for clade B strain V1V2 antigens, with some level of binding antibodies against clade C strains. Anti-V1V2 IgG3 response magnitude breadth, which correlated with decreased risk of infection in a previous efficacy trial, was of limited amplitude. Response rates to the antigens from the gp120 and gp140 breadth panels ranged from 7.7% to 94.1% and from 15.4% to 96.2% at Year 14, respectively. Following stimulation with gp120 peptide pool, highly polyfunctional gp120-specific CD4+ T-cells persisted up to Year 14, with high frequencies of CD40L tumor necrosis factor alpha (TNF-α), CD40L interleukin-2 (IL-2), CD40L TNF-α IL-2 and CD40L interferon gamma (IFN-γ) TNF-α IL-2 CD4+ T-cells, but no CD8+ T-cells detected. CONCLUSIONS: Persistent antibodies binding to HIV-1 envelope glycoproteins, including the V1V2-scaffold, and gp120-specific cellular immunity were observed in volunteers vaccinated 14 years earlier with the gp120-NefTat/AS01B vaccine candidate.

Final Analysis of a Trial of M72/AS01E Vaccine to Prevent Tuberculosis.

BACKGROUND: Results of an earlier analysis of a trial of the M72/AS01E candidate vaccine against Mycobacterium tuberculosis showed that in infected adults, the vaccine provided 54.0% protection against active pulmonary tuberculosis disease, without evident safety concerns. We now report the results of the 3-year final analysis of efficacy, safety, and immunogenicity. METHODS: From August 2014 through November 2015, we enrolled adults 18 to 50 years of age with M. tuberculosis infection (defined by positive results on interferon-γ release assay) without evidence of active tuberculosis disease at centers in Kenya, South Africa, and Zambia. Participants were randomly assigned in a 1:1 ratio to receive two doses of either M72/AS01E or placebo, administered 1 month apart. The primary objective was to evaluate the efficacy of M72/AS01E to prevent active pulmonary tuberculosis disease according to the first case definition (bacteriologically confirmed pulmonary tuberculosis not associated with human immunodeficiency virus infection). Participants were followed for 3 years after the second dose. Participants with clinical suspicion of tuberculosis provided sputum samples for polymerase-chain-reaction assay, mycobacterial culture, or both. Humoral and cell-mediated immune responses were evaluated until month 36 in a subgroup of 300 participants. Safety was assessed in all participants who received at least one dose of M72/AS01E or placebo. RESULTS: A total of 3575 participants underwent randomization, of whom 3573 received at least one dose of M72/AS01E or placebo, and 3330 received both planned doses. Among the 3289 participants in the according-to-protocol efficacy cohort, 13 of the 1626 participants in the M72/AS01E group, as compared with 26 of the 1663 participants in the placebo group, had cases of tuberculosis that met the first case definition (incidence, 0.3 vs. 0.6 cases per 100 person-years). The vaccine efficacy at month 36 was 49.7% (90% confidence interval [CI], 12.1 to 71.2; 95% CI, 2.1 to 74.2). Among participants in the M72/AS01E group, the concentrations of M72-specific antibodies and the frequencies of M72-specific CD4+ T cells increased after the first dose and were sustained throughout the follow-up period. Serious adverse events, potential immune-mediated diseases, and deaths occurred with similar frequencies in the two groups. CONCLUSIONS: Among adults infected with M. tuberculosis, vaccination with M72/AS01E elicited an immune response and provided protection against progression to pulmonary tuberculosis disease for at least 3 years. (Funded by GlaxoSmithKline Biologicals and Aeras; ClinicalTrials.gov number, NCT01755598.).

Persistence of HBsAg-specific antibodies and immune memory two to three decades after hepatitis B vaccination in adults.

The duration of protection after hepatitis B vaccination is not exactly known. This phase IV study evaluated antibody persistence and immune memory 20-30 years after adult immunization with recombinant hepatitis B vaccine (HBsAg vaccine, Engerix-B) in routine clinical practice. Men and women 40-60 years old, with documented evidence of vaccination with three or four HBsAg vaccine doses 20-30 years earlier and without subsequent booster, were enrolled and received HBsAg vaccine as challenge dose. HBsAg-specific antibodies (anti-HBs) and frequencies of HBsAg-specific circulating memory B cells and CD4+ T cells expressing combinations of activation markers (CD40L, IL2, IFNγ, TNFα) were measured prechallenge, 7 and 30 days postchallenge. Of 101 participants in the according-to-protocol cohort for immunogenicity, 90.1% had anti-HBs concentrations ≥ 10 mIU/mL prechallenge administration; 84.2% and 100% mounted an anamnestic response 7 and 30 days postchallenge, respectively. HBsAg-specific memory B and CD4+ T cells expressing at least two activation markers were low prechallenge and increased markedly postchallenge. These results suggest sustained immune memory and long-term protection 20-30 years after a complete primary HBsAg vaccination course during adulthood, in line with current recommendations that a booster is not needed in fully vaccinated immunocompetent adults.

Long-term safety and immunogenicity of the M72/AS01E candidate tuberculosis vaccine in HIV-positive and -negative Indian adults: Results from a phase II randomized controlled trial.

OBJECTIVES: To assess the long-term safety and immunogenicity of the M72/ Adjuvant System (AS01E) candidate tuberculosis (TB) vaccine up to 3 years post-dose 2 (Y3) in human immunodeficiency virus (HIV)-positive (HIV+) and HIV-negative (HIV-) Indian adults. METHODS: This phase II, double-blind, randomised, controlled clinical trial (NCT01262976) was conducted at YRG CARE Medical Centre, in Chennai, India, between January 2011 and June 2015.Three cohorts (HIV+ participants stable on antiretroviral therapy [ART; HIV+ART+], HIV+ ART-naïve [HIV+ART-], and HIV- participants) were randomised (1:1) to receive 2 doses of M72/AS01E (M72/AS01E groups) or saline (control groups) 1 month apart and were followed up toY3. Latent TB infection was assessed at screening using an interferon-gamma (IFN-γ) release assay (IGRA). Safety and immunogenicity results up to Y1 post-vaccination were reported elsewhere. Here, we report serious adverse events (SAEs), humoral and cell-mediated immune (CMI) responses to M72 recorded at Y2 and Y3. RESULTS: Of 240 enrolled and vaccinated participants, 214 completed the long-term follow-up part of the study.In addition to SAEs previously described, between Y1 and Y2 1 M72/AS01E recipient in the HIV+ART+ cohort reported 2 SAEs (sinus cavernous thrombosis and gastroenteritis) that were not considered as causally related to the study vaccine.Vaccination elicited persistent humoral immune responses against M72. At Y3, seropositivity rates were 97.1%, 66.7%, and 97.3% and geometric mean concentrations (GMCs) were 22.0  ELISA units (EU)/mL, 4.9 EU/mL, and 24.3 EU/mL in the HIV+ART+, HIV+ART-, and HIV- cohorts, respectively. Humoral immune response was lowest in the HIV+ART- cohort.In M72/AS01E recipients, no notable decrease in the frequency of M72-specific CD4 T-cells expressing ≥2 immune markers among interleukin-2 (IL-2), IFN-γ, tumour necrosis factor alpha (TNF-α) and CD40 ligand (CD40L) was observed at Y3 post-vaccination. Median values (interquartile range) of 0.35% (0.13-0.49), 0.05% (0.01-0.10), and 0.15% (0.09-0.22) were recorded in the HIV+ART+, HIV+ART- and HIV- cohorts, respectively. CD4 T-cell response was lowest in the HIV+ART- cohort.No CD8 T-cell response was observed. CONCLUSION: The cellular and humoral immune responses induced by M72/AS01E in HIV+ and HIV- adults persisted up to Y3 post-vaccination. No safety concerns were raised regarding administration of M72/AS01E to HIV+ adults. CLINICAL TRIAL REGISTRATION: NCT01262976 (www.clinicaltrials.gov).

Phase 2b Controlled Trial of M72/AS01E Vaccine to Prevent Tuberculosis.

BACKGROUND: A vaccine to interrupt the transmission of tuberculosis is needed. METHODS: We conducted a randomized, double-blind, placebo-controlled, phase 2b trial of the M72/AS01E tuberculosis vaccine in Kenya, South Africa, and Zambia. Human immunodeficiency virus (HIV)-negative adults 18 to 50 years of age with latent M. tuberculosis infection (by interferon-γ release assay) were randomly assigned (in a 1:1 ratio) to receive two doses of either M72/AS01E or placebo intramuscularly 1 month apart. Most participants had previously received the bacille Calmette-Guérin vaccine. We assessed the safety of M72/AS01E and its efficacy against progression to bacteriologically confirmed active pulmonary tuberculosis disease. Clinical suspicion of tuberculosis was confirmed with sputum by means of a polymerase-chain-reaction test, mycobacterial culture, or both. RESULTS: We report the primary analysis (conducted after a mean of 2.3 years of follow-up) of the ongoing trial. A total of 1786 participants received M72/AS01E and 1787 received placebo, and 1623 and 1660 participants in the respective groups were included in the according-to-protocol efficacy cohort. A total of 10 participants in the M72/AS01E group met the primary case definition (bacteriologically confirmed active pulmonary tuberculosis, with confirmation before treatment), as compared with 22 participants in the placebo group (incidence, 0.3 cases vs. 0.6 cases per 100 person-years). The vaccine efficacy was 54.0% (90% confidence interval [CI], 13.9 to 75.4; 95% CI, 2.9 to 78.2; P=0.04). Results for the total vaccinated efficacy cohort were similar (vaccine efficacy, 57.0%; 90% CI, 19.9 to 76.9; 95% CI, 9.7 to 79.5; P=0.03). There were more unsolicited reports of adverse events in the M72/AS01E group (67.4%) than in the placebo group (45.4%) within 30 days after injection, with the difference attributed mainly to injection-site reactions and influenza-like symptoms. Serious adverse events, potential immune-mediated diseases, and deaths occurred with similar frequencies in the two groups. CONCLUSIONS: M72/AS01E provided 54.0% protection for M. tuberculosis-infected adults against active pulmonary tuberculosis disease, without evident safety concerns. (Funded by GlaxoSmithKline Biologicals and Aeras; ClinicalTrials.gov number, NCT01755598 .).

Persistence of antibodies 20 y after vaccination with a combined hepatitis A and B vaccine.

Vaccination is the most effective and well-tolerated method of conferring long-term protection against hepatitis A and B viruses (HAV; HBV). Long-term studies are required to characterize the duration of protection and need for boosters. Following primary immunization of 150 and 157 healthy adults with 3-doses of combined hepatitis A/hepatitis B vaccine (HAB; Twinrix™, GSK Vaccines, Belgium) at 0-1-6 months in 2 separate studies, we measured vaccine-induced antibody persistence against HAV and HBV annually for 20 y (Study A: NCT01000324; Study B: NCT01037114). Subjects with circulating anti-HAV antibodies < 15 mIU/mL or with anti-hepatitis B surface antigen < 10 mIU/mL were offered an additional monovalent hepatitis A and/or B vaccine dose (Havrix™/Engerix™-B, GSK Vaccines, Belgium). Applying the immunogenicity results from these studies, mathematical modeling predicted long-term persistence. After 20 y, 18 and 25 subjects in studies A and B, respectively, comprised the long-term according-to-protocol cohort for immunogenicity; 100% and 96.0% retained anti-HAV antibodies ≥ 15 mIU/mL, respectively; 94.4% and 92.0% had anti-HBs antibodies ≥ 10 mIU/mL, respectively. Between Years 16-20, 4 subjects who received a challenge dose of monovalent hepatitis A vaccine (N = 2) or hepatitis B vaccine (N = 2), all mounted a strong anamnestic response suggestive of immune memory despite low antibody levels. Mathematical modeling predicts that 40 y after vaccination ≥ 97% vaccinees will maintain anti-HAV ≥ 15 mIU/mL and ≥ 50% vaccinees will retain anti-HBs ≥ 10 mIU/mL. Immunogenicity data confirm that primary immunization with 3-doses of HAB induces persisting anti-HAV and anti-HBs specific antibodies in most adults for up to 20 y; mathematical modeling predicts even longer-term protection.

Immunogenicity and safety of 3-dose primary vaccination with combined DTPa-HBV-IPV/Hib in Indian infants.

Multivalent combination vaccines have reduced the number of injections and therefore improved vaccine acceptance, timeliness of administration and global coverage. The hexavalent diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliovirus/Haemophilus influenzae type b (DTPa-HBV-IPV/Hib; Infanrix hexa™) vaccine, administered according to various schedules, is widely used for the primary vaccination of infants worldwide. In the current publication, we are presenting the immunogenicity and safety of 3 doses of DTPa-HBV-IPV/Hib vaccine when administered to Indian infants. 224 healthy infants (mean age 6.8 weeks) were vaccinated at 6-10-14 weeks (W) of age (n = 112) or 2-4-6 months (M) of age (n = 112). One month after the third vaccine dose, the seroprotection/seropositivity status against diphtheria, pertussis, tetanus, polio, hepatitis B and Hib antigens ranged from 98.6% to 100% in both groups. The vaccine response rate to the pertussis antigens ranged from 97% to 100%. Pain (6-10-14W group: 25.2%; 2-4-6M group: 13.4%) and fever (15.3% and; 15.2%, respectively) were the most frequently reported solicited local and general symptoms. Unsolicited adverse events were reported for 35.7% (6-10-14W group) and 22.3% (2-4-6M group) of subjects. No vaccine related serious adverse events were reported. In conclusion, the hexavalent DTPa-HBV-IPV/Hib vaccine was immunogenic and well tolerated, irrespective of the dosing schedule.

Safety, immunogenicity and persistence of immune response to the combined diphtheria, tetanus, acellular pertussis, poliovirus and Haemophilus influenzae type b conjugate vaccine (DTPa-IPV/Hib) administered in Chinese infants.

We conducted 3 phase III, randomized, open-label, clinical trials assessing the safety, reactogenicity (all studies), immunogenicity (Primary vaccination study) and persistence of immune responses (Booster study) to the combined diphtheria, tetanus, pertussis, poliomyelitis, and Haemophilus influenzae type b vaccine (DTPa-IPV/Hib) in Chinese infants and toddlers. In the Pilot study (NCT00964028), 50 infants (randomized 1:1) received 3 doses of DTPa-IPV/Hib at 2-3-4 (Group A) or 3-4-5 months of age (Group B). In the Primary study (NCT01086423), 984 healthy infants (randomized 1:1:1) received 3 doses of DTPa-IPV/Hib at 2-3-4 (Group A) or 3-4-5 (Group B) months of age, or concomitant DTPa/Hib and poliomyelitis (IPV) vaccination at 2-3-4 months of age (Control group); 825 infants received a booster dose of DTPa/Hib and IPV at 18-24 months of age (Booster study; NCT01449812). In the Pilot study, unsolicited symptoms were more frequent in Group A (16 versus 1 infant; mostly upper respiratory tract infection and pyrexia); this observation was attributed to an epidemic outbreak of viral infections. Non-inferiority of 3-dose primary vaccination with DTPa-IPV/Hib over separately administered DTPa/Hib and IPV was demonstrated for Group A (primary objective). Similar antibody concentrations were observed in all groups, except for anti-polyribosyl-ribitol phosphate and anti-poliovirus types 1-3 which were higher in DTPa-IPV/Hib recipients. Protective antibody levels against all vaccine antigens remained high until booster vaccination. Three-dose vaccination with DTPa-IPV/Hib had a clinically acceptable safety profile.

Lasting immune memory against hepatitis B in 12-13-year-old adolescents previously vaccinated with 4 doses of hexavalent DTPa-HBV-IPV/Hib vaccine in infancy.

BACKGROUND: Vaccinating infants against hepatitis B virus (HBV) is the most effective way of preventing the disease. However, since HBV exposure can increase during adolescence, it is essential that antibody persistence is maintained. We evaluated the antibody persistence and immune memory against hepatitis B, in 12-13 y olds who had received complete primary + booster vaccination with diphtheria-tetanus-acellular pertussis-hepatitis B-inactivated poliovirus/Haemophilus influenza type b (DTPa-HBV-IPV/Hib) vaccine in infancy. METHODS: Open phase-IV study conducted at 12 centers in Germany [NCT02052661]. Adolescents aged 12-13 y, vaccinated with 4 doses of DTPa-HBV-IPV/Hib (Infanrix hexa™, GSK Vaccines) in infancy, received a single challenge dose of monovalent pediatric hepatitis B vaccine (Engerix™-B Kinder; GSK Vaccines). Blood samples were taken before and 1-month post-challenge to measure anti-hepatitis B (anti-HBs) antibodies using a chemiluminescence immunoassay (seroprotection cut-off: ≥10 mIU/ml). Post-challenge adverse events (AEs) were monitored. RESULTS: 300 subjects were vaccinated; of 293 subjects in the ATP immunogenicity cohort, 60.5% had pre-challenge anti-HBs antibodies ≥10 mIU/ml, which rose to 97.6% post-challenge (≥100 mIU/ml in 94.1%). An anamnestic response was seen in 96.5% subjects. A 150-fold increase in antibody geometric mean concentrations was observed (22.4 to 3502.6 mIU/ml). Pain (44%) and fatigue (24.3%) were the most frequent solicited local and general AEs, respectively; 14.7% subjects reported unsolicited symptoms during the 31-day post-vaccination period. Two vaccine-unrelated serious AEs occurred. CONCLUSION: Vaccination with DTPa-HBV-IPV/Hib in infancy induces sustained seroprotection and immune memory against HBV, as shown by the strong anamnestic response to the hepatitis B vaccine challenge in 12-13 year-old adolescents.

Prospective clinical trial of hepatitis B vaccination in adults with and without type-2 diabetes mellitus.

Objective: Patients with diabetes mellitus are at increased risk for hepatitis B virus (HBV) infection and its complications. HBV vaccination is recommended for adults with diabetes in the United States and other countries. However, few studies have assessed safety and immunogenicity of hepatitis B vaccine in such patients. We assessed the safety and immunogenicity of recombinant hepatitis B vaccine in subjects with and without diabetes mellitus. METHODS: Prospective, multi-country controlled study in 21 centers ( www.clinicaltrials.gov NCT01627340). Four hundred and sixteen participants with Type-2 diabetes and 258 controls matched for age and body mass index (BMI) (2:1 ratio) received 3-doses of HBV vaccine (Engerix-B™, GSK Vaccines, Belgium) according to a 0, 1, 6 months schedule. Antibodies were measured against HBV surface antigen and expressed as seroprotection rates (anti-HBs ≥10mIU/mL) and geometric mean concentration (GMC). RESULTS: The median age and BMI in patients with diabetes and controls (according-to-protocol cohort) were 54 y and 32.1 kg/m2, and 53 y and 30.8 kg/m2, respectively. Seroprotection rates (GMCs) one month post-dose-3 were 75.4% (147.6 mIU/mL) and 82.0% (384.2 mIU/mL) in patients with diabetes and controls, respectively. Age-stratified seroprotection rates for patients with diabetes were 88.5% (20-39 years), 81.2% (40-49 years), 83.2% (50-59 years), and 58.2% (≥60 years). The overall safety profile of hepatitis B vaccine was similar between groups. CONCLUSIONS: Hepatitis B vaccine is immunogenic in patients with diabetes and has a similar safety profile to vaccination in healthy controls. Because increasing age was generally associated with a reduction in seroprotection rates, hepatitis B vaccine should be administered as soon as possible after the diagnosis of diabetes.

Immunity to hepatitis A and B persists for at least 15 years after immunisation of adolescents with a combined hepatitis A and B vaccine.

BACKGROUND: The exact duration of antibody persistence to hepatitis A and B and the need for booster dosing following primary immunisation remains undefined. A long-term study was designed to follow antibody persistence and immune memory on an annual basis for up to 15 years following vaccination during adolescence. METHODS: Subjects received a combined hepatitis A and B vaccine (Twinrix™, GSK Vaccines, Belgium) at 12-15 years of age, either as 2-dose of the adult formulation or 3-dose of the paediatric formulation. Blood samples were taken every year thereafter to assess antibody persistence and immune memory to hepatitis A and B. Antibodies to hepatitis A virus (anti-HAV) and hepatitis B surface antigen (anti-HBs) were measured at Years 11-15. At Year 15 immune memory was further assessed by measuring the anamnestic response to a challenge dose of the monovalent vaccine, which was administered to subjects whose antibody concentrations fell below the pre-defined cut-offs (anti-HAV: <15mIU/mL; anti-HBs: <10mIU/mL). RESULTS: 209 subjects returned for follow-up at Year 15 of whom 162 were included in the long-term according-to-protocol immunogenicity cohort. All subjects remained seropositive for anti-HAV antibodies, while 81.1% and 81.8% still had anti-HBs antibodies ≥10mIU/mL in the 2- and 3-dose groups, respectively. Following hepatitis B vaccine challenge dose administration to 19 subjects, all except one in the 3-dose group, mounted a robust anamnestic response. The safety and reactogenicity profile of the hepatitis B challenge was consistent with previous experience. CONCLUSION: Immunity to hepatitis A and B persists 15 years after adolescent vaccination with a combined hepatitis A and B vaccine. Highly effective anamnestic response indicates that a booster dose should not be required for 15 years after primary vaccination. TRIAL REGISTRATION: http://www.clinicaltrials.govNCT00875485.

Immunity to hepatitis B persists in adolescents 15-16 years of age vaccinated in infancy with three doses of hepatitis B vaccine.

OBJECTIVE: Vaccination of infants against hepatitis B virus (HBV) using hepatitis B vaccine is effective in preventing the infection during early childhood and there is a growing evidence of long-term protection. So far, no need for a booster dose has been identified in healthy subjects; however further follow-up continues to determine the exact duration of protection. We evaluated antibody persistence and immune response to a hepatitis B vaccine challenge dose in children aged 15-16 years, previously vaccinated with 3-doses of the same vaccine in infancy (third dose received before 18 months of age). METHODS: A single hepatitis B vaccine challenge dose containing 10µg hepatitis B surface (HBs) antigen was administered to adolescents aged 15-16 years. Blood samples were taken before and one month after the challenge dose to measure anti-HBs antibodies using a chemiluminescence immunoassay. Solicited local and general symptoms, as well as unsolicited and serious adverse events were recorded after the challenge dose. RESULTS: 303 subjects were enrolled, of whom 302 and 293 subjects formed the total vaccinated and according-to-protocol cohorts, respectively. Pre-challenge, 65.4% (95% CI: 59.6-70.9) subjects were seroprotected (anti-HBs antibody concentration ≥10mIU/mL). One month post-challenge, 97.9% (95% CI: 95.6-99.2) were seroprotected, while 90.8% (95% CI: 86.8-93.8) had anti-HBs antibody concentrations ≥100mIU/mL. The post-challenge geometric mean concentration (GMC; 4134.9 [95% CI: 3114.2-5490.1]) was 150-fold higher than the pre-challenge GMC. Overall, 96.9% (95% CI: 94.2-98.6) subjects mounted an anamnestic response. The safety and reactogenicity profile of the hepatitis B vaccine challenge dose was consistent with previous experience. CONCLUSIONS: Immunity to hepatitis B persists in 15-16 year old adolescents following primary vaccination in infancy. TRIAL REGISTRATION: http://www.clinicaltrials.govNCT01847430.

Primary and booster vaccination with an inactivated poliovirus vaccine (IPV) is immunogenic and well-tolerated in infants and toddlers in China.

INTRODUCTION: Replacing live-attenuated oral poliovirus vaccines (OPV) with inactivated poliovirus vaccines (IPV) is part of the global strategy to eradicate poliomyelitis. China was declared polio-free in 2000 but continues to record cases of vaccine-associated-poliomyelitis and vaccine-derived-poliovirus outbreaks. Two pilot safety studies and two larger immunogenicity trials evaluated the non-inferiority of IPV (Poliorix™, GSK Vaccines, Belgium) versus OPV in infants and booster vaccination in toddlers primed with either IPV or OPV in China. METHODS: In pilot safety studies, 25 infants received 3-dose IPV primary vaccination (Study A, www.clinicaltrial.gov NCT00937404) and 25 received an IPV booster after priming with three OPV doses (Study B, NCT01021293). In the randomised, controlled immunogenicity and safety trial (Study C, NCT00920439), infants received 3-dose primary vaccination with IPV (N=541) or OPV (N=535) at 2,3,4 months of age, and a booster IPV dose at 18-24 months (N=470, Study D, NCT01323647: extension of study C). Blood samples were collected before and one month post-dose-3 and booster. Reactogenicity was assessed using diary cards. Serious adverse events (SAEs) were captured throughout each study. RESULTS: Study A and B showed that IPV priming and IPV boosting (after OPV) was safe. Study C: One month post-dose-3, all IPV and ≥ 98.3% OPV recipients had seroprotective antibody titres towards each poliovirus type. The immune response elicited by IPV was non-inferior to Chinese OPV. Seroprotective antibody titres persisted in ≥ 94.7% IPV and ≥ 96.1% OPV recipients at 18-24 months (Study D). IPV had a clinically acceptable safety profile in all studies. Grade 3 local and systemic reactions were uncommon. No SAEs were related to IPV administration. CONCLUSION: Trivalent IPV is non-inferior to OPV in terms of seroprotection (in the Chinese vaccination schedule) in infant and toddlers, with a clinically acceptable safety profile.

Pertussis specific cell-mediated immune responses ten years after acellular pertussis booster vaccination in young adults.

BACKGROUND: One of the reasons for pertussis resurgence is waning immunity. Both humoral and cell mediated immunity (CMI) are essential for protection. The aim of this study was to evaluate CMI responses after acellular pertussis vaccination in young adults. METHODS: Fifty-seven young adults were followed for ten years after a diphtheria-tetanus acellular pertussis (dTpa) booster vaccination. A second booster was administrated at year 10. CMI was determined from peripheral blood mononuclear cells (PBMC) stimulated with vaccine antigens pertussis toxin (PT), filamentous hemagglutinin (FHA) and pertactin (PRN) before and one month after the second vaccination, using proliferation and IFN-γ and IL-17 ELISpot. In addition, the response to ten selected cytokines was measured from 14 subjects. RESULTS: Before the booster dose, positive proliferation was recognized in 51%, 53% and 89% of the subjects against PT, PRN and FHA, respectively. One month after, the positivity rate increased to 81%, 81% and 96%. Although the number of IFN-γ and IL-17 secreting cells was increased, the expression of most of the tested cytokines was found to be downregulated. After PT stimulation, only one (7.1%) subject had increased production in all cytokines, whereas six (42.9%) had decreased production of all cytokines. Ten subjects (71.4%) had decreased concentration of IFN-γ, the cytokine important for pertussis protection. CONCLUSIONS: CMI persists even when antibodies have decayed, and acellular pertussis vaccine enhances the CMI response. Further studies are needed to illustrate what factors cause the low production of some important cytokines.