Immunogenicity and Safety of 2 Doses of Avian Influenza A (H5N1) Vaccine Administered 3 vs. 8 Weeks Apart - A Multi-Center Non-Inferiority Placebo-Controlled Observer-Blinded Phase 2 Randomized Controlled Trial
Given the recent circulation of avian influenza A(H5N1) clade 2.3.4.4b strains in birds and mammals in North America, Canada procured a supply of Arepanrix™ H5N1 for potential use in persons at high risk of highly pathogenic avian influenza exposure. This vaccine received regulatory approval in 2013, to be given in two doses at least 3 weeks apart. There is limited data on the effect of various intervals between the two doses on immunogenicity and tolerability. In this study two intervals between doses will be compared (3 vs. 8 weeks apart).
⁃ Individuals in stable health (defined as no new onset or exacerbation of pre-existing chronic disease three months prior to vaccination) 18-59 years of age.
⁃ Able to comply with the trial procedures.
⁃ Informed consent signed prior to trial-specific procedures.
⁃ If a person is at risk of becoming pregnant, has practiced adequate contraception for 28 days prior to visit 1, and has a negative pregnancy test on the day of vaccination and has agreed to continue adequate contraception until 60 days after the final vaccination.
∙ Risk of pregnancy is defined as any cis woman and/or gender divergent individual assigned female at birth or with reproductive capacity who is sexually active with individuals with sperm-producing capabilities.
∙ Individual who are post-menopausal or permanently sterile (hysterectomy, bilateral salpingectomy) are not considered at risk of pregnancy. A post-menopausal state is defined as a no menses for 12 months.
∙ Effective contraception methods are:
• Combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation:
‣ Oral
⁃ Intravaginal
⁃ Transdermal
• Progestogen-only hormonal contraception associated with inhibition of ovulation:
‣ Oral
⁃ Injectable
⁃ Implantable
• Intra-uterine device (IUD) with or without hormonal release.
• Vasectomised partner, provided that this partner is your sole sexual partner and that the vasectomised partner has received a medical assessment of the surgical success.
• Credible self-reported history of heterosexual abstinence prior to and for at least 28 days after the vaccine.
∙ Effective contraception methods are:
• Combined (estrogen and progestogen containing) hormonal contraception associated with inhibition of ovulation:
‣ Oral
⁃ Intravaginal
⁃ Transdermal
• Progestogen-only hormonal contraception associated with inhibition of ovulation:
‣ Oral
⁃ Injectable
⁃ Implantable
• Intra-uterine device (IUD) with or without hormonal release.
• Vasectomised partner, provided that this partner is your sole sexual partner and that the vasectomised partner has received a medical assessment of the surgical success.
• Credible self-reported history of heterosexual abstinence prior to and for at least 28 days after the vaccine.