152. Protective Antibody Levels 7.5 Years after Primary Vaccination in Adolescence with a Recombinant, 4-Component, Meningococcal Serogroup B Vaccine (4CMenB) and Response to a Booster Dose in Adolescents and Young Adults: Phase IIIb Clinical Findings
Session: Oral Abstract Session: Adult and Adolescent Vaccines
Thursday, October 4, 2018: 11:15 AM
Room: S 158

Background: 4CMenB has been shown to be immunogenic with an acceptable safety profile in infants and young adolescents. However, no data on long-term persistence after primary vaccination in adolescents are available. This is the first study to assess antibody persistence, booster response, and safety of 4CMenB in adolescents and young adults up to 7.5 years (y) following the primary vaccination in adolescence.

Methods: This phase 3b, open-label, extension study (NCT02446743) assessed the antibody persistence and booster response at 4y (Canada and Australia, NCT01423084) or 7.5y (Chile, NCT00661713) after primary vaccination with 4CMenB (following 0+1-, 0+2-, or 0+6-month [m] schedules), compared with vaccine-naïve (VN), healthy controls. Chilean follow-on (FO) and VN participants aged 18–24y received either a booster dose of 4CMenB 7.5y post-primary series (Group FO, N=131) or 2 primary doses, 1m apart (Group VN, N=150). Immunogenicity was measured using human serum bactericidal antibody assay (hSBA) against antigen-specific strains. Immune response was evaluated 1m post-booster vaccination and compared to VN controls at 1m post-first dose. Kinetics of antibody responses were measured at 3, 7, and 30 days (d) post-vaccination. Safety was assessed.

Results: Antibody levels waned at 7.5y post-primary vaccination in Group FO, but were higher than in Group VN at baseline, for all antigens except NHBA (Table). At 1m post-booster/post-first dose, 93–100% (Group FO) and 62–93% (Group VN) of participants had hSBA titres ≥4; GMTs ranged between 41–1951 (Group FO) and 9.43–46 (Group VN) (Table). The percentages of FO participants with hSBA titres ≥4 remained similar to pre-booster for all 4 antigens at 3d, increased at 7d, and remained unchanged or increased further 30d post-booster. The reactogenicity of 4CMenB was consistent with previous observations in this age group; no safety concerns were identified during the study.

Conclusion: Antibody levels in adolescents and young adults declined at 7.5y after a 2-dose primary series of 4CMenB, but were higher than baseline levels in VN controls. An additional dose of 4CMenB elicited strong anamnestic responses – substantially higher than 1 dose in VN controls.

Funding: GlaxoSmithKline Biologicals SA

Terry Nolan, MBBS PhD1, Miguel O'Ryan, MD2, María Elena Santolaya, MD3, Ferdinandus De Looze, MBBS FRACGP MSc4, Helen Marshall, MD MBBS MPH5, Peter Richmond, MBBS FRACP6, Sam Henein, MD7, Paul Rheault, MD, CCFP8, Ken Heaton, MD9, Kirsten Perrett, MBBS FRACP PhD10, Hartley Garfield, MD11, Anil Gupta, MD CCFP FCFP11, Murdo Ferguson, Mb.ChB, CCFP(EM) FCFp Dip Sport Med(Can)12, Diego D'Agostino, MSc13 and Daniela Toneatto, MD14, (1)University of Melbourne and Murdoch Children's Research Institute, Melbourne, Victoria, Australia, (2)Microbiology and Immunology Program/Institute of Biomedical Sciences, University Of Chile, Santiago, Chile, (3)Hospital Dr Luis Calvo Mackenna, Faculty of Medicine, Universidad de Chile, Santiago, Chile, (4)AusTrials Pty Ltd and University of Queensland, Brisbane, Australia, (5)University of Adelaide and Women’s and Children’s Hospital, Adelaide, South Australia, Australia, (6)University of Western Australia School of Paediatrics and Child Health and Vaccine Trials Group, Telethon Kids Institute, Princess Margaret Hospital for Children, Perth, Australia, (7)SKDS Research Inc Newmarket, Newmarket, ON, Canada, (8)Medicor Research Inc., Sudbury, ON, Canada, (9)Devonshire Clinical Research Inc, Woodstock, ON, Canada, (10)Murdoch Children's Research Institute, University of Melbourne and Royal Children's Hospital, Melbourne, Australia, (11)The Hospital for Sick Children, University of Toronto, Toronto, ON, Canada, (12)Colchester Research Group, Truro, NS, Canada, (13)GSK, Amsterdam, Netherlands, (14)GSK, Siena, Italy

Disclosures:

T. Nolan, GSK: Research Contractor and Scientific Advisor , Research grant . Pfizer: Research Contractor , Research grant .

M. O'Ryan, GSK: Investigator , Research support .

M. E. Santolaya, None

F. De Looze, GSK: Investigator and Research Contractor , Research grant and Research support .

H. Marshall, Pfizer: Grant Investigator and Investigator , Research grant . GSK: Grant Investigator and Investigator , Research grant .

P. Richmond, GSK: Grant Investigator and Scientific Advisor , Grant recipient .

S. Henein, SKDS Research Inc: Investigator , Research payment .

P. Rheault, None

K. Heaton, Devonshire Clinical Research Inc: Investigator , Research payment .

K. Perrett, None

H. Garfield, None

A. Gupta, None

M. Ferguson, GSK: Investigator , Salary from independent research clinic,CRG .

D. D'Agostino, GSK: Employee , Salary .

D. Toneatto, GSK: Employee and Shareholder , Salary .

Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 3rd with the exception of research findings presented at the IDWeek press conferences.