The world production capacity of influenza vaccines is a concern in face of the potential influenza pandemic. The use of adjuvants could increase several fold the current installed production capacity. Bordetella pertussis monophosphyl lipid A (MPLA) was produced by acid hydrolysis of LPS, obtained as a by-product of its removal from cellular pertussis vaccine, generating a product with 4 side chains. We have investigated different formulations including MPLA alone or combined with Al(OH)(3) as adjuvants for an inactivated split virion influenza vaccine. Our results demonstrate that MPLA at concentrations as low as 0.01 microg per dose of vaccine is effective, even with a 4-fold reduction of the regular vaccine dose, as measured by the induction of protective hemagglutination inhibition (HAI) titers. Al(OH)(3) can be combined with 0.01-10 microg MPLA, inducing even higher immune responses. Al(OH)(3) caused a drift of the immune response induced by the vaccine towards a Th2 profile, as evaluated by an increase in the IgG1:IgG2a ratio, while MPLA showed a more balanced response. Moreover, the use of MPLA and Al(OH)(3) combination led to the induction of the highest IgG levels together with the secretion of both IFN-gamma and IL-4. Although cell-mediated immune responses have not been usually taken into account for influenza vaccine formulations, they may be relevant for the induction of cross-protection as well as immunological memory for both inter-pandemic and pandemic influenza vaccines. Our results indicate that a more favorable profile of both humoral and cell-mediated immune responses may be obtained using the MPLA/Al(OH)(3) formulation.
Recombinant yeast-derived hepatitis B vaccine manufactured by Instituto Butantan was administered in two groups of adult volunteers (I, II) following two different schedules of immunization. In the first trial (10 &mgr;g doses and 0, 1, 3 months vaccination schedule) 106 individuals completed the full immunization program. The results of seroconversion by age group varied from 70 to 100% and the GMT from 46.5 to 124.9 mIU mL-1. In the second trial with 68 individuals (for dosage comparison and 0, 1, 6 months vaccination schedule) indicated that the vaccine formulated in 20 &mgr;g was more effective than in 10 &mgr;g. The adverse reactions observed in the vaccinees were less frequent than the ones previously found since the introduction of similar vaccines.
Technology transfer is a promising approach to increase vaccine production at an affordable price in developing countries. In the case of influenza, it is imperative that developing countries acquire the technology to produce pandemic vaccines through the transfer of know-how, as this will be the only way for the majority of these countries to face the huge demand for vaccine created by influenza pandemics. Access to domestically produced influenza vaccine in such health crises is thus an important national defence strategy. However, technology transfer is not a simple undertaking. It requires a committed provider who is willing to transfer a complete production process, and not just the formulation and fill-finish parts of the process. It requires a recipient with established experience in vaccine production for human use and the ability to conduct research into new developments. In addition, the country of the recipient should preferably have sufficient financial resources to support the undertaking, and an internal market for the new vaccine. Technology transfer should create a solid partnership that results in the joint development of new competency, improvements to the product, and to further innovation. The Instituto Butantan-sanofi pasteur partnership can be seen as a model for successful technology transfer and has led to the technological independence of the Instituto Butantan in the use a strategic public health tool.
Consecutive lots of H5N1 (A/Vietnam/1194/2004 - NIBRG-14) split virion and whole virus vaccines were produced in a pilot-scale laboratory. The average yields of vaccine doses (15 microg HA) per egg were 0.57 doses for H5N1 split virion vaccine and 1.12 for H5N1 whole virus vaccine, compared to 2.09 doses for the seasonal H3N2 split virion vaccine. H5N1 split virion vaccine lots complied with WHO protein content criteria, while some lots of the H5N1 whole virus vaccine showed protein content per dose higher than the limit established. All lots of both vaccines showed ovalbumin (OVA) concentration below the recommended limit. Dose sparing strategies using adjuvant formulations using aluminum hydroxide (Al(OH)(3)) and monophosphoryl lipid A (MPLA) from Bordetella pertussis were tested in mice. Both 3.75 microg HA and 7.5 microg HA of H5N1 split virion vaccine with Al(OH)(3) or Al(OH)(3) plus MPLA in aqueous suspension showed higher hemagglutination-inhibition (HAI) titers when compared to the same vaccine dose without any adjuvant. Immunization with the H5N1 inactivated whole virus vaccine was also performed using 3.75 microg HA and HAI titers were higher than those induced by the split virion vaccine. Moreover, the use of Al(OH)(3) with MPLA as an emulsion induced a further increase in HAI titers.
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