Immunogenicity and safety of subunit influenza vaccines in pregnant women

Abstract

Pregnancy is a condition of modulated immune suppression, so this group of patients has increased risk of infectious diseases.Trivalent subunit vaccines, unadjusted Agrippal S1 (group I) and immunoadjuvant Grippol Plus (group II), containing 5 μg of actual influenza virus strains, were administered respectively to 37 and 42 women in the second and third trimester of physiological pregnancy.The administration of subunit influenza vaccines was accompanied by the development of local reactions in no more than 10% of patients, compared with 4.9% of the 41 pregnant women in the placebo group (group III). Systemic reactions were of a general somatic nature, did not differ between vaccinated and placebo groups, and were not associated with vaccination. Physiological births in groups I, II and III were 94.6%, 92.9% and 85.4%, respectively, and the birth rates of children without pathologies were 91.9%, 90.5% and 80.5%, respectively, and were comparable between groups. Vaccination stimulated the production of protective antibodies against influenza virus strains in 64.8–94.5% of patients after immunisation with an unadjusted vaccine and in 72.5–90.0% of patients after the administration of an immunoadjuvant vaccine. After 9 months, antibody levels were recorded in 51.3–72.9% in group I and 54.2–74.2% in group II. Immunisation against influenza in pregnant women provided a high level of seroprotection and seroconversion. Nevertheless, the level of seroprotection against the influenza strain A(H3N2, Victoria) was slightly lower in the group immunised with an unadjusted vaccine compared to those vaccinated with the immunoadjuvant vaccine.

Analysis of the safety and immunogenicity profile of an azoximer bromide polymer-adjuvanted subunit influenza vaccine.

“…A symptomatic complex of systemic reactions following vaccination during pregnancy has been described, which was most often associated with psychological state and anxiety of the development of AEs in response to vaccination. 33 The intrinsic reactogenicity of AZB could not be determined directly, in the absence of randomised clinical trials comparing SU vaccines with identical amounts of HA, but with or without AZB. However, meta-regression analysis of the available data detected no difference in reaction rates after adjustment for mean age and the amount of HA administered, and predicted that AZB was not associated with intrinsic reactogenicity.…”

Advances in Development and Application of Influenza Vaccines

“…For instance, the Influvac ® (Solvay Pharmaceuticals BV, Weesp, The Netherlands) and Agrippal ® (Chiron SRL, now Novartis Vaccines, Viaflorentina, Italy) vaccines have shown good immunogenicity, safety, and tolerability in healthy children, adults, and elderlies. As pregnant women are highly susceptible to influenza virus infection, trivalent influenza subunit vaccines Agrippal S1 and Grippol Plus are specifically designed to prevent influenza in pregnant women, which meet the Committee for Proprietary Medicinal Products (CPMP) standards and have been shown to provide high-titer antibodies for pregnant women and immune-protective effects for infants for as long as 6 months ( 85 , 86 ). Besides human use, subunit influenza vaccines for swine and poultry have also been widely studied.…”

The Effect of Influenza Vaccines on Maturation of Dendritic Cells Generated from Bone Marrow

“…Due to Polyoxidonium, all Grippol family vaccines contain 3-times lower antigen content in one immunizing dose -5 mcg per strain, in comparison to 15mcg per strain in other subunit and split influenza vaccines. This provides Grippol family vaccines with higher safety profile [15][16][17][18][19][20][21][22][23][24][25][26][27]. These recommendations were made based on relevant clinical trials results followed by many years practical mass vaccine application experience [28][29].…”