Safety and immunogenicity of an MF59®-adjuvanted A/H1N1 pandemic influenza vaccine in children from three to seventeen years of age. Issue 1 (1st January 2015)

• Record Type: Journal Article
• Authors: Knuf, Markus; Leroux-Roels, Geert; Rümke, Hans. C.; Abarca, Katia; Rivera, Luis; Lattanzi, Maria; Pedotti, Paola; Arora, Ashwani; Kieninger-Baum, Dorothee; Della Cioppa, Giovanni
• Is Part Of: Vaccine. Volume 33:Issue 1(2015)
• Page Start: 174
• Page End: 181
• Publication Date: 2015-01-01
• Subjects: www.clinicaltrials.gov (NCT00971542); Pandemic influenza -- A/H1N1 -- Vaccine -- MF59 -- Paediatric; Vaccines -- Periodicals; 615.372
• DOI: 10.1016/j.vaccine.2014.10.085
• Languages: English
• ISSNs: 0264-410X

Abstract

Highlights: Immunogenicity and safety of MF59-adjuvanted monovalent A/H1N1 pandemic influenza vaccine were assessed in children 3–17 years old. Long-term antibody persistence after priming and a robust antibody response to booster immunization in all vaccination groups. A high proportion reached the stringent HI cut-off titre ≥1:330 postvaccination. MF59-adjuvanted monovalent influenza vaccine was generally well tolerated; no serious AEs in the study. Abstract: Objectives: This study was designed to identify the optimal dose of an MF59 ® -adjuvanted, monovalent, A/H1N1 influenza vaccine in healthy paediatric subjects. Methods: Subjects aged 3–8 years ( n = 194) and 9–17 years ( n = 160) were randomized to receive two primary doses of A/H1N1 vaccine containing either 3.75 μg antigen with half a standard dose of MF59 adjuvant, 7.5 μg antigen with a full dose of MF59, or (children 3–8 years only), a non-adjuvanted 15 μg formulation. A booster dose of MF59-adjuvanted seasonal influenza vaccine including homologous A/H1N1 strain was given one year after priming. Immunogenicity was assessed by haemagglutination inhibition (HI) and microneutralization assays. Vaccine safety was assessed throughout the study (up to 18 months). Results: A single priming dose of either MF59-adjuvanted formulation was sufficient to meet the European licensure criteria for pandemic influenza vaccines (HI titres ≥1:40 > 70%; seroconversion > 40%; and GMR > 2.5). Two non-adjuvanted vaccine doses were required to meet the same licensure criteria. After first and second doses, percentage of subjects with HI titres ≥1:40 were between 97% and 100% in the adjuvanted vaccine groups compared with 68% and 91% in the non-adjuvanted group, respectively. Postvaccination seroconversion rates ranged from 91% to 98% in adjuvanted groups and were 68% (first dose) and 98% (second dose) in the non-adjuvanted group. HI titres ≥1:330 after primary doses were achieved in 69% to 90% in adjuvanted groups compared with 41% in the non-adjuvanted group. Long-term antibody persistence after priming and a robust antibody response to booster immunization were observed in all vaccination groups. All A/H1N1 vaccine formulations were generally well tolerated. No vaccine-related serious adverse events occurred, and no subjects were withdrawn from the study due to an adverse event. Conclusions: An MF59-adjuvanted influenza vaccine containing 3.75 μg of A/H1N1 antigen was well tolerated and sufficiently immunogenic to meet all the European licensure criteria after a single dose in healthy children 3–17 years old.