A multi-criteria decision making approach to identify a vaccine formulation.

This article illustrates the use of a multi-criteria decision making approach, based on desirability functions, to identify an appropriate adjuvant composition for an influenza vaccine to be used in elderly. The proposed adjuvant system contained two main elements: monophosphoryl lipid and α-tocopherol with squalene in an oil/water emulsion. The objective was to elicit a stronger immune response while maintaining an acceptable reactogenicity and safety profile. The study design, the statistical models, the choice of the desirability functions, the computation of the overall desirability index, and the assessment of the robustness of the ranking are all detailed in this manuscript.

Immunogenicity and safety of different formulations of an adjuvanted glycoprotein D genital herpes vaccine in healthy adults: a double-blind randomized trial.

Herpes simplex virus (HSV) type 2 (HSV-2) is the main cause of genital and neonatal herpes and is highly prevalent worldwide. Previous phase I and II studies showed the immunogenicity and safety of the candidate prophylactic HSV-2 glycoprotein D-based subunit vaccine (gD2-AS04), containing aluminum hydroxide and 3-O-deacylated monophosphoryl lipid A (MPL) as adjuvant (AS04), in healthy adults. The primary objective of the study presented here was to compare the immunogenicity and safety of five different vaccine formulations: 3 different antigen doses [20, 40 or 80 µg of truncated glycoprotein D from HSV-2 strain (gD-2t)], different aluminum salts [AlPO4 or Al(OH)3], different preservatives or different volumes of vaccine (0.5 or 1 ml). One hundred and fifty healthy men and women aged 18-45 years, with negative serological markers for HSV-1 and HSV-2 infection, were vaccinated with one of 5 formulations of the gD2-AS04 candidate vaccine according to a 0-, 1-, 6-month schedule. No statistically significant difference was observed in humoral or cellular immune responses between different antigen doses or the different aluminum salts, preservatives or volumes of vaccine. The gD2-AS04 vaccine was well tolerated by study participants for the duration of the study period. Local symptoms were more frequently reported than general symptoms, with muscle stiffness and/or injection site redness being the most frequently reported. Overall, the incidence of adverse events was comparable in all groups. Based on these results the gD2-AS04 formulation, containing 20 µg of gD-2t, was selected for evaluation of prophylactic efficacy in further clinical trials.

Immunologic non-inferiority of a newly licensed inactivated trivalent influenza vaccine versus an established vaccine: a randomized study in US adults.

A trivalent inactivated influenza vaccine (Fluarix (™) , GlaxoSmithKline Biologicals) was licensed under US accelerated approval regulations. We performed a randomized, observer-blind, post-approval study to demonstrate its immunological non-inferiority versus an established US-licensed vaccine (primary endpoint). Adult (including elderly) subjects received a single injection of newly-licensed vaccine (n = 923) or established vaccine (n = 922). Serum hemagglutination-inhibition titers were determined pre-vaccination and 21-28 days after vaccination. Non-inferiority was assessed by post-vaccination geometric mean titer (GMT) ratio (upper 95% confidence interval [CI] ≤ 1.5) and difference in seroconversion rate (upper 95% CI ≤ 0.1) for all three vaccine strains. Safety was monitored for 6 months. The newly-licensed vaccine was non-inferior to the established vaccine in all subjects (≥ 18 years) and in elderly subjects (≥ 65 years). Adjusted GMT ratios (established/newly-licensed) against the H1N1, H3N2 and B strains were 0.65 (95% CI: 0.58, 0.73), 0.93 (0.83, 1.04) and 1.13 (1.03, 1.25) for all subjects and 0.75 (0.67, 0.85), 0.95 (0.82, 1.09) and 1.13 (1.00, 1.27) for elderly subjects. Corresponding values for the differences in seroconversion rate (established minus newly-licensed) were -0.12 (-0.16, -0.07), -0.02 (-0.06, 0.03) and 0.01 (-0.04, 0.06) for all subjects and -0.11 (-0.16, -0.05), -0.02 (-0.07, 0.04) and 0.02 (-0.04, 0.08) for elderly subjects. The most common adverse events with both vaccines were injection site pain, fatigue and headache, and no serious adverse events or deaths were considered related; there were no clinically relevant differences between the vaccines. In conclusion, the newly-licensed vaccine was well tolerated and immunologically non-inferior to the established vaccine for all three vaccine strains in the whole population and the elderly.

Immunogenicity and reactogenicity of a trivalent influenza split vaccine in previously unvaccinated children aged 6-9 and 10-13 years.

Children previously unvaccinated against influenza are recommended to receive two doses of trivalent inactivated influenza vaccine (TIV). This study assessed the age limit for a second dose of TIV in previously unvaccinated children. Two hundred and twenty-four children were immunized with TIV (Influsplit SSW/Fluarix; GlaxoSmithKline Biologicals). Subjects aged 6-9 years (n=110) received two doses of TIV 4 weeks apart; those aged 10-13 years (n=114) received a single dose. Serum haemagglutination inhibiting (HI) antibody titers were evaluated before and after each vaccination. CHMP criteria for HI antibody response were met for all three vaccine strains after one vaccine dose in children 10-13 years and after two doses in children 6-9 years. A marked benefit was observed in 8-year-old children after a second dose even though one dose would be sufficient against all strains. Our results provide additional evidence that Influsplit SSW/Fluarix is well tolerated and highly immunogenic in children and support recommendations that previously unvaccinated children aged <9 years should receive two doses of influenza vaccine.

Safety and efficacy of a recombinant hepatitis E vaccine.

BACKGROUND: Hepatitis E virus (HEV) is an important cause of viral hepatitis. We evaluated the safety and efficacy of an HEV recombinant protein (rHEV) vaccine in a phase 2, randomized, double-blind, placebo-controlled trial. METHODS: In Nepal, we studied 2000 healthy adults susceptible to HEV infection who were randomly assigned to receive three doses of either the rHEV vaccine or placebo at months 0, 1, and 6. Active (including hospital) surveillance was used to identify acute hepatitis and adverse events. The primary end point was the development of hepatitis E after three vaccine doses. RESULTS: A total of 1794 subjects (898 in the vaccine group and 896 in the placebo group) received three vaccine doses; the total vaccinated cohort was followed for a median of 804 days. After three vaccine doses, hepatitis E developed in 69 subjects, of whom 66 were in the placebo group. The vaccine efficacy was 95.5% (95% confidence interval [CI], 85.6 to 98.6). In an intention-to-treat analysis that included all 87 subjects in whom hepatitis E developed after the first vaccine dose, 9 subjects were in the vaccine group, with a vaccine efficacy of 88.5% (95% CI, 77.1 to 94.2). Among subjects in a subgroup randomly selected for analysis of injection-site findings and general symptoms (reactogenicity subgroup) during the 8-day period after the administration of any dose, the proportion of subjects with adverse events was similar in the two study groups, except that injection-site pain was increased in the vaccine group (P=0.03). CONCLUSIONS: In a high-risk population, the rHEV vaccine was effective in the prevention of hepatitis E. (ClinicalTrials.gov number, NCT00287469 [ClinicalTrials.gov].).

Enhanced humoral and memory B cellular immunity using HPV16/18 L1 VLP vaccine formulated with the MPL/aluminium salt combination (AS04) compared to aluminium salt only.

An effective virus-like particle (VLP) based prophylactic vaccine designed to protect against persistent infection with human papillomavirus (HPV) types 16 and 18 and subsequent lesion development will need to induce a strong humoral and cellular immune response capable of providing long-term protection. Our objective was to evaluate the ability of an HPV16/18 L1 VLP vaccine formulated with the AS04 adjuvant system (3-O-desacyl-4'-monophosphoryl lipid A (MPL) and aluminium salt) to induce an immune response of higher magnitude and persistence compared to a vaccine formulated with aluminium salt only. We demonstrated that MPL adsorbed onto aluminium salt retains its capacity to activate an innate immune response as assessed by the production of TNFalpha by human monocytes (U937). In addition, vaccination of mice, monkeys or human subjects with AS04 formulations induced higher total anti-L1 VLP16 and L1 VLP18 antibody responses (1.6-8.5-fold) than the aluminium salt only formulations. The enhanced antibody response induced by the AS04 vaccine formulation (1.6-4.1-fold) in monkeys and humans was shown to be targeted to functional neutralising L1 VLP16 and L1 VLP18 epitopes as assessed by V5/J4 specific ELISAs or HPV16 and HPV18 pseudo-neutralization assays. The enhanced immune profile observed with the AS04 formulation in terms of both total, V5/J4 specific and neutralizing antibodies was shown to persist for at least 3.5-year post-vaccination in human subjects. Finally, using the newly developed B cell ELISPOT assay we also demonstrated that the AS04 formulation elicited an increased frequency (2.2-5.2-fold) of HPV L1 VLP specific memory B cells when compared with the aluminium salt only formulations. These data strongly support the role of the AS04 adjuvant, which includes the immunostimulant MPL, in triggering a persistent vaccine-induced immune response of high quality.

Primary and booster vaccination with DTPw-HB/Hib pentavalent vaccine in Costa Rican children who had received a birth dose of hepatitis B vaccine.

OBJECTIVE: The DTPw-HB/Hib pentavalent combination vaccine has been developed following recommendations of the World Health Organization for the introduction of hepatitis B (HB) and Haemophilus influenzae type b (Hib) vaccines into routine childhood vaccination programs. The objectives of this study were to: 1) analyze the immunogenicity and the reactogenicity of the DTPw-HB/Hib pentavalent combination vaccine in comparison to separate injections of DTPw-HB and Hib vaccines as primary vaccination in a group of children who had received a dose of HB vaccine at birth and 2) in the second year of life to assess the antibody persistence as well as the response to a DTPw-HB/Hib or DTPw/Hib booster. METHODS: In the first part of the study (primary-vaccination stage), conducted in 1998-1999, we analyzed the immunogenicity and reactogenicity of the DTPw-HB/Hib combination vaccine in comparison to separate injections of DTPw-HB and Hib vaccines as primary vaccination at 2, 4, and 6 months of age in 207 Costa Rican children who had received a dose of HB vaccine at birth. Later, in the booster-vaccination stage of the study, in 1999-2000, in a subset of the children (69 toddlers, now 15-18 months old), antibody persistence was measured, and response to a DTPw-HB/Hib or DTPw/Hib booster was also assessed. RESULTS: In both primary-vaccination groups, at least 97.5% of the infants reached protective levels of antibodies (seropositivity) against the antigens employed in the vaccines. The DTPw-HB/Hib pentavalent combination vaccine did not result in more local reactions than did the DTPw-HB vaccine alone, and, in terms of general reactions, there was no clinically significant difference between the combination or separate injections, and with the pentavalent vaccine having the benefit of needing one less injection. Nine months after the third dose of the primary-vaccination course, antibody persistence was similar in both groups, with over 93% of children still having protective/seropositive titers for Hib, HB, and tetanus and about 50% for diphtheria and Bordetella pertussis. At 15 months of age, virtually all the toddlers responded with a strong boost response to all the vaccine antigens, whether they received the DTPw-HB/Hib pentavalent vaccine or the DTPw/Hib vaccine as a booster. Both booster regimens were equally well tolerated, indicating that up to five doses of the HB vaccine can be given without impact on safety. CONCLUSIONS: Our study confirms that the DTPw-HB/Hib pentavalent vaccine is highly immunogenic as a primary vaccination in children who received an HB vaccine at birth, with the pentavalent combination inducing both persisting immunity and boostable memory. The pentavalent vaccine was safe both for primary and booster vaccinations. Thus, this study in Costa Rican infants supports the routine use of the pentavalent DTPw-HB/Hib vaccine as part of childhood vaccination programs in Latin America and the Caribbean.

Primary and booster vaccination with DTPw-HB/Hib pentavalent vaccine in Costa Rican children who had received a birth dose of hepatitis B vaccine / Vacunación primaria y de refuerzo con la vacuna pentavalente DTPw-HB/Hib en niños costarricenses vacunados al nacer contra la hepatitis B

Objective. The DTPw-HB/Hib pentavalent combination vaccine has been developed following recommendations of the World Health Organization for the introduction of hepatitis B (HB) and Haemophilus influenzae type b (Hib) vaccines into routine childhood vaccination programs. The objectives of this study were to: 1) analyze the immunogenicity and the reactogenicity of the DTPw-HB/Hib pentavalent combination vaccine in comparison to separate injections of DTPw-HB and Hib vaccines as primary vaccination in a group of children who had received a dose of HB vaccine at birth and 2) in the second year of life to assess the antibody persistence as well as the response to a DTPw-HB/Hib or DTPw/Hib booster. Methods. In the first part of the study (primary-vaccination stage), conducted in 1998-1999, we analyzed the immunogenicity and reactogenicity of the DTPw-HB/Hib combination vaccine in comparison to separate injections of DTPw-HB and Hib vaccines as primary vaccination at 2, 4, and 6 months of age in 207 Costa Rican children who had received a dose of HB vaccine at birth. Later, in the booster-vaccination stage of the study, in 1999-2000, in a subset of the children (69 toddlers, now 15-18 months old), antibody persistence was measured, and response to a DTPw-HB/Hib or DTPw/Hib booster was also assessed. Results. In both primary-vaccination groups, at least 97.5 percent of the infants reached protective levels of antibodies (seropositivity) against the antigens employed in the vaccines. The DTPw-HB/Hib pentavalent combination vaccine did not result in more local reactions than did the DTPw-HB vaccine alone, and, in terms of general reactions, there was no clinically significant difference between the combination or separate injections, and with the pentavalent vaccine having the benefit of needing one less injection. Nine months after the third dose of the primary-vaccination course, antibody persistence was similar in both groups, with over 93 percent of children still having protective/seropositive titers for Hib, HB, and tetanus and about 50 percent for diphtheria and Bordetella pertussis. At 15 months of age, virtually all the toddlers responded with a strong boost response to all the vaccine antigens, whether they received the DTPw-HB/Hib pentavalent vaccine or the DTPw/Hib vaccine as a booster. Both booster regimens were equally well tolerated, indicating that up to five...