Corinne Desaint

Immunological efficacy of a three-dose schedule of hepatitis A vaccine in HIV-infected adults: HEPAVAC study.

Background:The immunogenicity of vaccines, including vaccine against hepatitis A virus (HAV), is impaired in patients with HIV infection, requiring revised immunization regimens. Methods:We evaluated the immunological efficacy and safety of a 3-dose schedule of hepatitis A vaccine in HIV-infected adults. HAV-seronegative HIV-infected adults were randomized to receive either 3 doses of 1440 UI of hepatitis A vaccine (HAVRIX; GlaxoSmithKline, Marly le Roi, France) at weeks 0, 4, and 24 (46 patients) or 2 doses 24 weeks apart (49 patients). Results:At week 28, seroconversion, defined as an anti-HAV antibody ≥20 mIU/mL, occurred in 82.6% and 69.4% of patients in the 3-dose and the 2-dose group, respectively (P = 0.13, intent-to-treat analysis, missing data = nonresponder), and in 88.4% and 72.3% of patients in the 3-dose and the 2-dose group, respectively (P = 0.06, observed analysis). Only 37.9% of patients experienced seroconversion after 1 vaccine dose (intent-to-treat analysis). Anti-HAV antibody geometric mean titers were 323 and 132 mIU/mL in the 3-dose group and 138 and 67 mIU/mL in the 2-dose group, respectively, 28 (P = 0.03) and 72 weeks (P = 0.05) after the first vaccine dose. There were no serious adverse events associated with the vaccine. Multivariate analysis showed no treatment group effect but indicated that absence of tobacco smoking (odds ratio = 2.92, 95% confidence interval: 1.07 to 7.97; P = 0.04) was an independent predictor of response to HAV vaccine. Conclusions:In HIV-infected adults, immunogenicity of hepatitis A vaccine is poor. Three doses of vaccine were safe and increased antibody titers.

Immunogenicity and safety of an HIV-1 lipopeptide vaccine in healthy adults: a phase 2 placebo-controlled ANRS trial

Background:French National Agency for Research on AIDS and Viral Hepatitiss HIV-LIPO-5 vaccine includes five HIV-1 peptides, containing multiple CD8+ and CD4+ T-cell epitopes and coupled to a palmitoyl tail. Whether HIV-LIPO-5 immunogenicity varies with the dose is unknown. Methods:HIV-negative volunteers were randomized to receive HIV-LIPO-5 vaccine at 50 μg/lipopeptide (N = 32), 150 μg/lipopeptide (N = 32), 500 μg/lipopeptide (N = 33) or placebo (N = 34) at weeks 0, 4, 12 and 24. HIV-1-specific CD8+ (interferon-γ ELISpot on peripheral blood mononuclear cells cultured for 12 days) and CD4+ responses (peripheral blood mononuclear cell lymphoproliferation) were assessed at baseline, after each injection and at week 48. Results:Local reactions were dose-dependent but no differences in systemic reactions appeared between groups. Sustained (at least on two separate occasions) CD8+ response rates to at least one given HIV-1 pool were obtained in 22 of 32 (69%), 21 of 33 (64%) and 21 of 34 (62%) individuals for LIPO-5 50, 150 and 500 groups, respectively (P ≤ 0.0001 for all comparisons to the placebo). Cumulative CD4+ response rates were obtained in 15 of 32 (47%), 18 of 33 (55%) and 15 of 34 (44%) individuals (P < 0.0001 for all comparisons to placebo). At week 48, CD8+ responses persisted in 47 of 91 (52%) HIV-LIPO-5 recipients. Conclusion:Doses of 50, 150 and 500 μg of French National Agency for Research on AIDS and Viral Hepatitiss HIV-LIPO-5 vaccine were able to elicit HIV-specific sustained CD8+ and CD4+ T-cell responses in healthy adults. Safety is good and all doses appear appropriate in further ‘prime-boost’ trials.

Short Communication: Long-Term Persistence of Vaccine-Induced HIV Seropositivity among Healthy Volunteers

Long-term persistence of HIV vaccine-induced seropositivity in uninfected HIV vaccine recipients remains unknown. The duration of HIV humoral-induced responses was assessed in 72 volunteers who had received rgp160 and/or HIV recombinant canarypox virus constructs able to induce immune responses detectable using standard serological tests. Among the 43 rgp160 recipients, 94% and 83% remained HIV seropositive after 5 and 8 years of follow-up, respectively, while all the 29 volunteers who had received canarypox constructs alone were seronegative after 5 years. Because rgp160 induces long-term persistence (>8 years) of vaccine-induced HIV seropositivity, volunteers should be offered long-term follow-up to monitor their serological evolution.

Long-term CD4(+) and CD8(+) T-cell responses induced in HIV-uninfected volunteers following intradermal or intramuscular administration of an HIV-lipopeptide vaccine (ANRS VAC16).

BACKGROUND We have shown that the intradermal (ID) administration of an HIV-1 lipopeptide candidate vaccine (LIPO-4) is well tolerated in healthy volunteers, with one fifth the IM dose delivered by this route inducing HIV-1-specific CD8(+) T-cell responses of a magnitude and quality similar to those achieved by IM administration. In this long-term follow-up, we aimed to investigate the sustainability and epitopic breadth of the immune responses induced. METHODS In a prospective multicentre trial, 68 healthy volunteers were randomised to receive, at weeks 0, 4 and 12, either a 0.5 ml IM (500 μg of each lipopeptide; 35 volunteers) dose or a 0.1 ml ID (100 μg of each lipopeptide; 33 volunteers) dose of the LIPO-4 vaccine, in the deltoid region of the non-dominant arm. All 68 volunteers received the first two vaccinations, and 44 volunteers in the ID group and 22 in the IM group received the third. We describe here the long-term CD8(+) and CD4(+) T-cell immune responses, up to 48 weeks after the first immunisation. RESULTS Response frequency was highest at week 14 for CD4(+) T cells, at 85% (28/33) for the IM group and 61% (20/33) for the ID group (p=0.027), and at week 48 for CD8(+) T cells, at 36% (12/33) for the ID group and 31% (11/35) for the IM group (p=0.67). Response rates tended to be lower for volunteers receiving the third vaccination boost, whether IM or ID. Finally, we also observed a striking change in the specificity of the CD8(+) T-cell responses induced shortly (2 weeks) or several months (48 weeks) after LIPO-4 vaccination. CONCLUSION Lipopeptide vaccines elicited sustainable CD4(+) and CD8(+) T-cell responses, following IM or ID administration. CD8(+) T-cell responses had shifted and expanded to different epitopes after one year of follow-up. These results should facilitate the design of the next generation of prime-boost trials with repeated doses of lipopeptide vaccines.

Long-term immunogenicity of two doses of 2009 A/H1N1v vaccine with and without AS03(A) adjuvant in HIV-1-infected adults.

Objective:In immunocompromised patients, alternative schedules more immunogenic than the standard influenza vaccine regimen are necessary to enhance and prolong vaccine efficacy. We previously reported that the AS03A-adjuvanted 2009 A/H1N1v vaccine yielded a higher short-term immune response than the nonadjuvanted one in HIV-1-infected adults. This study reports the long-term persistence of the immune response. Design and methods:In a prospective, multicenter, randomized, patient-blinded trial, two doses of AS03A-adjuvanted H1N1v vaccine containing 3.75 &mgr;g haemagglutinin (n = 155; group A) or nonadjuvanted H1N1v vaccine containing 15 &mgr;g haemagglutinin (n = 151; group B), were administered 21 days apart. Haemagglutination inhibition and neutralizing antibodies were assessed 6 and 12 months after vaccination. Results:In group A and B, the seroprotection rates were 83.7 and 59.4% at month 6, and 70.4 and 49.3 at month 12, respectively. In a multivariate analysis, persistence of seroprotection 12 months after vaccination was negatively associated with current smoking (odds ratio = 0.6, P = 0.03) and positively related with the AS03A-adjuvanted H1N1v vaccine (odds ratio = 2.7, P = 0.0002). Conclusion:In HIV-1-infected adults, two doses of adjuvanted influenza vaccine induce long-term persistence of immune response up to 1 year after vaccination.

Humoral immunity of dTap-IPV vaccine (REPEVAX®) administered one month after dT-IPV vaccine (REVAXIS®) in adults with unknown vaccination history

This study was to assess the humoral immune response induced by a vaccination schedule routinely used in France in 18-50 year old adults with unknown vaccination history. In this monocentric, prospective study, subjects received one dose of REVAXIS® (dT-IPV, diphtheria, tetanus and poliomyelitis (inactivated) vaccine (adsorbed, reduced antigen(s) content)) (Visit 1) followed by one dose of REPEVAX® (dTap-IPV, diphtheria, tetanus, pertussis (acellular, component) and poliomyelitis (inactivated) vaccine (adsorbed, reduced antigen(s) content)) one month later (Visit 2). Antibodies against diphtheria, tetanus, poliomyelitis types 1, 2 and 3, and pertussis toxin (PT) were measured one month after the administration of REPEVAX® (Visit 3). A total of 136 subjects were included in the study, but blood samples were available for only 73 subjects. Their mean age at inclusion was 33.2 ± 7.3 years. 49.3% of the 73 subjects originated from the WHO African Region, 6.8% from the WHO Western Pacific Region and 5.5% from the WHO European Region. One month after REPEVAX® administration, all subjects had seroprotective antibody titers against diphtheria and tetanus (≥0.1 IU/mL), poliomyelitis types 2 and 3 (≥ 8 1/dil); one subject (1.4%) did not have antibodies against poliomyelitis type 1. The rate of anti-PT seropositivity (≥8 EU/mL) was 94.4%. One dose of REPEVAX® administered one month after a dose of REVAXIS® in subjects with unknown vaccination history induced a high humoral response. These results validate a vaccination schedule routinely used for years that rapidly elicits effective immunization against diphtheria, tetanus, poliomyelitis and pertussis.

Immune activation, smoking, and vaccine response.

Here, we tested the hypothesis that chronic immune activation might fuel interindividual variability in vaccine response in the model of hepatitis B virus vaccine in HIV-1-infected adults. We observed that the marker of inflammation soluble tumour necrosis factor receptor I (sTNFRI) is predictive for vaccine efficiency. We also established that the link between tobacco smoking and impaired vaccine response might be mediated by inflammation. These data are a step forward in personalized vaccination.

Production of TNF-alpha ex vivo is predictive of an immune response to flu vaccination in a frail elderly population.

ObjectiveTo investigate the relationship between the response to influenza vaccination and the ability to produce proinflamatory cytokines in elderly subjects.MethodsWhole blood samples from 25 elderly subjects collected before influenza vaccination were stimulated with the influenza vaccine in order to evaluate the secretion of five specific cytokines: TNFα, IFNα, IFNγ, IL2 and IL10. The results were correlated with the increased HAI antibody titres two weeks after vaccination.ResultsOnly 30% of elderly individuals seroconverted after vaccination. Although 50 to 70% of the cohort did not produce TNFα, IFNα, IFNγ, IL2 or IL10, all of the individuals who seroconverted were able to produceTNFα. Furthermore production of IFNγ, with or without production of IFNα/β, was not associated with a better response to the vaccine.ConclusionProduction of TNFα appears to be primordial for an efficient vaccine response, and may provide a predictive marker for the humoral response to vaccination. It may also provide the basis for evaluating agents designed to rescue TNFα-producing cells. This study emphasises a need to rescue TNF-producing cell function.