A dose-ranging study of a subunit Respiratory Syncytial Virus subtype A vaccine with and without aluminum phosphate adjuvantation in adults > or =65 years of age.
We studied the safety and immunogenicity of a Respiratory Syncytial Virus (RSV)-A vaccine containing subunit antigens F, G and M in older persons, and its effect on influenza vaccine immunogenicity. In a dose-ranging, placebo-controlled, blinded trial 561 adults > or =65 years of age at five Canadian sites were randomized to one intramuscular injection of either 100, 50 or 25 microg RSV-A-alum vaccine or 100 microg non-adjuvanted RSV-A vaccine, or alum-placebo. All participants were offered inactivated influenza vaccine on day 32. Immunization was well tolerated and reactogenicity was similar between the RSV and influenza vaccines and the alum-placebo. Only the 100 microg non-adjuvanted RSV vaccine achieved the primary immunogenicity outcome of eliciting a > or =4-fold rise in neutralizing antibody (NA) titres against RSV-A in > or =50% of participants at day 32. Geometric mean titres against RSV-A and -B at all points were comparable in 100 microg adjuvanted and non-adjuvanted groups. At day 32, a > or =4-fold haemagluttinin inhibition (HI) antibody response or HI > or =40 to Influenza (A-H3N2) was seen in >74% of participants; no difference was seen between groups. A subunit non-alum-containing RSV-A vaccine was well tolerated in a large population > or =65 years and did not interfere with influenza vaccine immunogenicity. This RSV-A-based vaccine demonstrated NA rise which could provide seasonal protection against severe RSV illnesses from RSV-A or -B and warrants further testing to determine its efficacy in the prevention of clinical illness in elderly persons.
Langley
Joanne M
JM
Canadian Center for Vaccinology, Dalhousie University and IWK Health Centre, Halifax, NS, Canada. jmlangle@dal.ca
Sales
Valerie
V
McGeer
Allison
A
Guasparini
Roland
R
Predy
Gerald
G
Meekison
William
W
Li
Minran
M
Capellan
Jose
J
Wang
Elaine
E
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000368:Aged; D000369:Aged, 80 and over; D017607:Aluminum Compounds / Q000276:immunology*; D000914:Antibodies, Viral / Q000276:immunology; D000917:Antibody Formation; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D008297:Male; D009500:Neutralization Tests; D010710:Phosphates / Q000276:immunology*; D018357:Respiratory Syncytial Virus Infections / Q000276:immunology / Q000517:prevention & control*; D022261:Respiratory Syncytial Virus Vaccines / Q000276:immunology*; D012136:Respiratory Syncytial Viruses / Q000276:immunology; D022223:Vaccines, Subunit / Q000276:immunology
D000276:Adjuvants, Immunologic; D017607:Aluminum Compounds; D000914:Antibodies, Viral; D010710:Phosphates; D022261:Respiratory Syncytial Virus Vaccines; D022223:Vaccines, Subunit; C012714:aluminum phosphate