Olivier Godeaux

Efficacy of an Adjuvanted Herpes Zoster Subunit Vaccine in Older Adults

BACKGROUND In previous phase 1-2 clinical trials involving older adults, a subunit vaccine containing varicella-zoster virus glycoprotein E and the AS01B adjuvant system (called HZ/su) had a clinically acceptable safety profile and elicited a robust immune response. METHODS We conducted a randomized, placebo-controlled, phase 3 study in 18 countries to evaluate the efficacy and safety of HZ/su in older adults (≥50 years of age), stratified according to age group (50 to 59, 60 to 69, and ≥70 years). Participants received two intramuscular doses of the vaccine or placebo 2 months apart. The primary objective was to assess the efficacy of the vaccine, as compared with placebo, in reducing the risk of herpes zoster in older adults. RESULTS A total of 15,411 participants who could be evaluated received either the vaccine (7698 participants) or placebo (7713 participants). During a mean follow-up of 3.2 years, herpes zoster was confirmed in 6 participants in the vaccine group and in 210 participants in the placebo group (incidence rate, 0.3 vs. 9.1 per 1000 person-years) in the modified vaccinated cohort. Overall vaccine efficacy against herpes zoster was 97.2% (95% confidence interval [CI], 93.7 to 99.0; P<0.001). Vaccine efficacy was between 96.6% and 97.9% for all age groups. Solicited reports of injection-site and systemic reactions within 7 days after vaccination were more frequent in the vaccine group. There were solicited or unsolicited reports of grade 3 symptoms in 17.0% of vaccine recipients and 3.2% of placebo recipients. The proportions of participants who had serious adverse events or potential immune-mediated diseases or who died were similar in the two groups. CONCLUSIONS The HZ/su vaccine significantly reduced the risk of herpes zoster in adults who were 50 years of age or older. Vaccine efficacy in adults who were 70 years of age or older was similar to that in the other two age groups. (Funded by GlaxoSmithKline Biologicals; ZOE-50 ClinicalTrials.gov number, NCT01165177.).

A Field Trial to Assess a Blood-Stage Malaria Vaccine

BACKGROUND Blood-stage malaria vaccines are intended to prevent clinical disease. The malaria vaccine FMP2.1/AS02(A), a recombinant protein based on apical membrane antigen 1 (AMA1) from the 3D7 strain of Plasmodium falciparum, has previously been shown to have immunogenicity and acceptable safety in Malian adults and children. METHODS In a double-blind, randomized trial, we immunized 400 Malian children with either the malaria vaccine or a control (rabies) vaccine and followed them for 6 months. The primary end point was clinical malaria, defined as fever and at least 2500 parasites per cubic millimeter of blood. A secondary end point was clinical malaria caused by parasites with the AMA1 DNA sequence found in the vaccine strain. RESULTS The cumulative incidence of the primary end point was 48.4% in the malaria-vaccine group and 54.4% in the control group; efficacy against the primary end point was 17.4% (hazard ratio for the primary end point, 0.83; 95% confidence interval [CI], 0.63 to 1.09; P=0.18). Efficacy against the first and subsequent episodes of clinical malaria, as defined on the basis of various parasite-density thresholds, was approximately 20%. Efficacy against clinical malaria caused by parasites with AMA1 corresponding to that of the vaccine strain was 64.3% (hazard ratio, 0.36; 95% CI, 0.08 to 0.86; P=0.03). Local reactions and fever after vaccination were more frequent with the malaria vaccine. CONCLUSIONS On the basis of the primary end point, the malaria vaccine did not provide significant protection against clinical malaria, but on the basis of secondary results, it may have strain-specific efficacy. If this finding is confirmed, AMA1 might be useful in a multicomponent malaria vaccine. (Funded by the National Institute of Allergy and Infectious Diseases and others; ClinicalTrials.gov number, NCT00460525.).

Immunogenicity and Safety of Human Papillomavirus (HPV)-16/18 AS04-Adjuvanted Vaccine in Healthy Boys Aged 10–18 Years

PURPOSE The human papillomavirus (HPV)-16/18 AS04-adjuvanted vaccine (Cervarix) has been shown to be well-tolerated and immunogenic in females aged 10 to 55 years, and up to 100% effective for the prevention of HPV-16/18 infection and associated precancerous cervical lesions in females aged 15 to 25 years. This study is the first to evaluate the immunogenicity and safety of the vaccine in males. METHODS Healthy males aged 10 to 18 years were randomized (2:1 ratio) to receive HPV-16/18 AS04-adjuvanted vaccine (n = 181) or hepatitis B virus (HBV) control vaccine (n = 89) at 0, 1, and 6 months, and were followed for 7 months. RESULTS All initially seronegative subjects in the HPV-16/18 group seroconverted for HPV-16 and 18 (ELISA) at month 2. At month 7, all subjects were seropositive, and the HPV-16 and -18 antibody levels were, respectively, four- and twofold higher than at month 2. The anti-HPV-16 and -18 antibody responses for males aged 10 to 18 years and 10 to 14 years, respectively, were higher than those reported for females aged 15 to 25 years and 10 to 14 years, respectively, in a previous study. The reactogenicity profiles of the HPV-16/18 AS04 and HBV vaccines were similar, except that pain and swelling at the injection site were more common in the HPV-16/18 group. However, vaccine-related symptoms did not affect compliance with the three-dose course, which was equally high (97%) in both groups. CONCLUSIONS The HPV-16/18 AS04-adjuvanted vaccine is immunogenic and well tolerated in boys aged 10 to 18 years. However, further data on the potential public health benefits of vaccination of boys are required before any recommendations can be made.

Safety and Long-term Humoral Immune Response in Adults After Vaccination With an H1N1 2009 Pandemic Influenza Vaccine With or Without AS03 Adjuvant

BACKGROUND In this study (NCT00985088) we evaluated different formulations of an H1N1 2009 pandemic influenza vaccine that deliver various viral hemagglutinin (HA) doses with or without AS03 (a tocopherol-based oil-in-water adjuvant system). METHODS A total of 1340 healthy subjects aged ≥18 years were randomized to receive 1 or 2 doses of an adjuvanted (3.75-μg HA/AS03(A) or 1.9-μg HA/AS03(B)) or nonadjuvanted vaccine formulation. Safety and immunogenicity (by hemagglutination-inhibition [HI] assay) after each dose and 6 months after dose 1 are reported here. RESULTS A single dose of AS03(A)-adjuvanted 3.75-μg HA H1N1 2009 induced the strongest immune responses in subjects aged 18-64 years (seroprotection rate [SPR], 97.2%; seroconversion rate [SCR], 90.1%) as well as in subjects aged >64 years (SPR, 91.1%; SCR, 78.2%) 21 days after vaccination. Six months after dose 1, subjects who received 2 doses of either the adjuvanted formulation or 1 dose of the adjuvanted 3.75-μg HA formulation continued to meet all Center for Biologics Evaluation and Research and Committee for Medicinal Products for Human Use criteria. All formulations had clinically acceptable safety profiles. CONCLUSION A single dose of the 3.75-μg HA AS03(A)-adjuvanted H1N1 2009 influenza vaccine was highly immunogenic in both age strata (18-64 and >64 years), inducing long-term persistence of the immune response until at least 6 months after dose 1.

Results from tandem Phase 1 studies evaluating the safety, reactogenicity and immunogenicity of the vaccine candidate antigen Plasmodium falciparum FVO merozoite surface protein-1 (MSP142) administered intramuscularly with adjuvant system AS01

BackgroundThe development of an asexual blood stage vaccine against Plasmodium falciparum malaria based on the major merozoite surface protein-1 (MSP1) antigen is founded on the protective efficacy observed in preclinical studies and induction of invasion and growth inhibitory antibody responses. The 42 kDa C-terminus of MSP1 has been developed as the recombinant protein vaccine antigen, and the 3D7 allotype, formulated with the Adjuvant System AS02A, has been evaluated extensively in human clinical trials. In preclinical rabbit studies, the FVO allele of MSP142 has been shown to have improved immunogenicity over the 3D7 allele, in terms of antibody titres as well as growth inhibitory activity of antibodies against both the heterologous 3D7 and homologous FVO parasites.MethodsTwo Phase 1 clinical studies were conducted to examine the safety, reactogenicity and immunogenicity of the FVO allele of MSP142 in the adjuvant system AS01 administered intramuscularly at 0-, 1-, and 2-months: one in the USA and, after evaluation of safety data results, one in Western Kenya. The US study was an open-label, dose escalation study of 10 and 50 μg doses of MSP142 in 26 adults, while the Kenya study, evaluating 30 volunteers, was a double-blind, randomized study of only the 50 μg dose with a rabies vaccine comparator.ResultsIn these studies it was demonstrated that this vaccine formulation has an acceptable safety profile and is immunogenic in malaria-naïve and malaria-experienced populations. High titres of anti-MSP1 antibodies were induced in both study populations, although there was a limited number of volunteers whose serum demonstrated significant inhibition of blood-stage parasites as measured by growth inhibition assay. In the US volunteers, the antibodies generated exhibited better cross-reactivity to heterologous MSP1 alleles than a MSP1-based vaccine (3D7 allele) previously tested at both study sites.ConclusionsGiven that the primary effector mechanism for blood stage vaccine targets is humoral, the antibody responses demonstrated to this vaccine candidate, both quantitative (total antibody titres) and qualitative (functional antibodies inhibiting parasite growth) warrant further consideration of its application in endemic settings.Trial registrationsClinical Trials NCT00666380

Long-term immunogenicity of an AS03-adjuvanted influenza A(H1N1)pdm09 vaccine in young and elderly adults: An observer-blind, randomized trial

Abstract Background This study (NCT00979602) evaluated the immunogenicity and relative protective efficacy of one dose of influenza A(H1N1)pdm09 vaccine with or without AS03 (an α-tocopherol oil-in-water emulsion based Adjuvant System). Methods Four thousands and forty-eight healthy adults aged ≥18 years were randomized (1:1) to receive one dose of either the adjuvanted split virion (3.75μg hemagglutinin antigen [HA]/AS03) or non-adjuvanted (15μg HA) vaccine. Hemagglutination inhibition [HI] antibody response was evaluated before vaccination and at Days 21, 42 and 182 (Month 6). Safety of the study vaccines was evaluated during the entire study duration. Results At Day 21, both study vaccines induced HI immune responses meeting the US regulatory criteria in subjects 18–64 years (seroprotection rate [SPR]: 98.0% [97.1–98.6]; seroconversion rate [SCR]: 89.7% [88.0–91.2] in the AS03-adjuvanted group; SPR: 91.4% [89.9–92.8]; SCR: 74.6% [72.3–76.9] in the non-adjuvanted group) and >64 years of age (SPR: 86.0% [82.5–89.0]; SCR: 75.3% [71.1–79.2] in the AS03-adjuvanted group; SPR: 69.1% [64.6–73.3]; SCR: 56.7% [52.0–61.3] in the non-adjuvanted group). The AS03-adjuvanted vaccine induced higher HI geometric mean titers than the non-adjuvanted vaccine at all time points. At Month 6, only subjects 18–64 years of age from both vaccine groups still met the US regulatory criteria (SPR: 82.1% [80.0–84.1]; SCR: 62.3% [59.6–64.8] in the AS03-adjuvanted group; SPR: 75.3% [72.9–77.5]; SCR: 53.7% [51.0–56.4] in the non-adjuvanted group). Protective efficacy was not evaluated due to low number of RT-qPCR-confirmed A(H1N1)pdm09 influenza cases. Through Month 12, 216 serious adverse events (in 157 subjects: 84 in the AS03-adjuvanted and 73 in the non-adjuvanted group) and 12 potentially immune mediated diseases (5 in the AS03-adjuvanted and 7 in the non-adjuvanted group) were reported. Conclusion A single dose of either adjuvanted or non-adjuvanted influenza A(H1N1)pdm09 vaccine induced protective HI antibody levels against the A/California/7/2009 strain that persisted through Month 6 in the 18–64 years population.

Extended Safety, Immunogenicity and Efficacy of a Blood-Stage Malaria Vaccine in Malian Children: 24-Month Follow-Up of a Randomized, Double-Blinded Phase 2 Trial

Background The FMP2.1/AS02A candidate malaria vaccine was tested in a Phase 2 study in Mali. Based on results from the first eight months of follow-up, the vaccine appeared well-tolerated and immunogenic. It had no significant efficacy based on the primary endpoint, clinical malaria, but marginal efficacy against clinical malaria in secondary analyses, and high allele-specific efficacy. Extended follow-up was conducted to evaluate extended safety, immunogenicity and efficacy. Methods A randomized, double-blinded trial of safety, immunogenicity and efficacy of the candidate Plasmodium falciparum apical membrane antigen 1 (AMA1) vaccine FMP2.1/AS02A was conducted in Bandiagara, Mali. Children aged 1–6 years were randomized in a 1∶1 ratio to receive FMP2.1/AS02A or control rabies vaccine on days 0, 30 and 60. Using active and passive surveillance, clinical malaria and adverse events as well as antibodies against P. falciparum AMA1 were monitored for 24 months after the first vaccination, spanning two malaria seasons. Findings 400 children were enrolled. Serious adverse events occurred in nine participants in the FMP2.1/AS02A group and three in the control group; none was considered related to study vaccination. After two years, anti-AMA1 immune responses remained significantly higher in the FMP2.1/AS02A group than in the control group. For the entire 24-month follow-up period, vaccine efficacy was 7.6% (p = 0.51) against first clinical malaria episodes and 9.9% (p = 0.19) against all malaria episodes. For the final 16-month follow-up period, vaccine efficacy was 0.9% (p = 0.98) against all malaria episodes. Allele-specific efficacy seen in the first malaria season did not extend into the second season of follow-up. Interpretation Allele-specific vaccine efficacy was not sustained in the second malaria season, despite continued high levels of anti-AMA1 antibodies. This study presents an opportunity to evaluate correlates of partial protection against clinical malaria that waned during the second malaria season. Trial Registration Clinicaltrials.gov NCT00460525 NCT00460525

Immunogenicity and safety of an adjuvanted herpes zoster subunit candidate vaccine in adults ≥ 50 years of age with a prior history of herpes zoster: A phase III, non-randomized, open-label clinical trial

ABSTRACT This phase III, non-randomized, open-label, multi-center study (NCT01827839) evaluated the immunogenicity and safety of an adjuvanted recombinant subunit herpes zoster (HZ) vaccine (HZ/su) in adults aged ≥ 50 y with prior physician-documented history of HZ. Participants (stratified by age: 50–59, 60–69 and ≥ 70 y) received 2 doses of HZ/su 2 months apart and were followed-up for another 12 months. Anti-glycoprotein E (gE) antibodies were measured by enzyme-linked immunosorbent assay before vaccination and 1 month after the second dose (Month 3). Solicited local and general adverse events (AEs) were recorded for 7 d and unsolicited AEs for 30 d after each vaccination. Serious AEs were recorded until study end. The primary immunogenicity objective was met if the lower limit of the 95% confidence interval (CI) of the vaccine response rate (VRR), defined as a 4-fold increase in anti-gE over baseline, at Month 3 was ≥ 60%. 96 participants (32/age group) were enrolled. The primary immunogenicity objective was met, as the VRR at Month 3 was 90.2% (95% CI: 81.7–95.7). Geometric mean anti-gE antibody concentrations at Month 3 were similar across age groups. 77.9% and 71.6% of participants reported local and general solicited AEs, respectively. The most frequent solicited AEs were pain at injection site, fatigue, headache, myalgia and shivering. The HZ/su vaccine was immunogenic in adults aged ≥ 50 y with a physician-documented history of HZ, and no safety concerns were identified.

AS03B-Adjuvanted H5N1 Influenza Vaccine in Children 6 Months Through 17 Years of Age: A Phase 2/3 Randomized, Placebo-Controlled, Observer-Blinded Trial

Abstract Background. This phase 2/3, randomized, placebo-controlled, observer-blinded study assessed the immunogenicity, reactogenicity, and safety of an inactivated, split-virion H5N1 influenza vaccine (A/Indonesia/5/2005) in children aged 6 months through 17 years. Methods. Children received 2 influenza vaccine doses 21 days apart, each containing 1.9 µg of hemagglutinin and AS03B adjuvant (5.93 mg of α-tocopherol). The randomization ratio was 8:3 for vaccine to placebo, with equal allocation between 3 age strata (6–35 months, 3–8 years, and 9–17 years). Immunogenicity against the vaccine strain was assessed 21 days after the first and second vaccine doses for all vaccinees, at day 182 for half, and at day 385 for the remaining half. Reactogenicity after each dose and safety up to 1 year after vaccination were evaluated. Results. Within each age stratum, the lower limit of the 98.3% confidence interval for the day 42 seroprotection rate was ≥70%, thus fulfilling the US and European licensure criteria. The immune responses elicited by vaccine persisted well above baseline levels for 1 year. The vaccine was more reactogenic than placebo, but no major safety concerns were identified. Conclusions. AS03B-adjuvanted H5N1 influenza vaccine was immunogenic and showed an acceptable safety profile in all age groups studied. Clinical Trials Registration. NCT01310413.

Immune Responses to a Recombinant Glycoprotein E Herpes Zoster Vaccine in Adults Aged 50 Years or Older

Abstract Background The herpes zoster subunit vaccine (HZ/su), consisting of varicella-zoster virus glycoprotein E (gE) and AS01B Adjuvant System, was highly efficacious in preventing herpes zoster in the ZOE-50 and ZOE-70 trials. We present immunogenicity results from those trials. Methods Participants (ZOE-50: ≥50; ZOE-70: ≥70 years of age) received 2 doses of HZ/su or placebo, 2 months apart. Serum anti-gE antibodies and CD4 T cells expressing ≥2 of 4 activation markers assessed (CD42+) after stimulation with gE-peptides were measured in subcohorts for humoral (n = 3293) and cell-mediated (n = 466) immunogenicity. Results After vaccination, 97.8% of HZ/su and 2.0% of placebo recipients showed a humoral response. Geometric mean anti-gE antibody concentrations increased 39.1-fold and 8.3-fold over baseline in HZ/su recipients at 1 and 36 months post-dose 2, respectively. A gE-specific CD42+ T-cell response was shown in 93.3% of HZ/su and 0% of placebo recipients. Median CD42+ T-cell frequencies increased 24.6-fold (1 month) and 7.9-fold (36 months) over baseline in HZ/su recipients and remained ≥5.6-fold above baseline in all age groups at 36 months. The proportion of CD4 T cells expressing all 4 activation markers increased over time in all age groups. Conclusions Most HZ/su recipients developed robust immune responses persisting for 3 years following vaccination. Clinical Trials Registration NCT01165177; NCT01165229.