Both the vaccine and control were stored at 2-8 C, and were provided as a sterile liquid that was injected intramuscularly (deltoid) at a volume of 0.5 mL/dose in a two-dose regimen on day 0 (day of randomisation) and day 14.
No onsite dose preparation was required. Each glass vial contained a single dose of either vaccine or control formulation that required no additional dilution steps. No prophylactic medication (ibuprofen or acetaminophen) was prescribed either before or after vaccination.
Follow-up visits were scheduled on days 7, 28, 42, 104, and 194 after vaccination. The first 50 participants (who received either 3 mcg Algel-IMDG with antigen [the lowest antigen concentration] or control) were monitored for 7 days after completing vaccination for safety. The independent data safety monitoring board reviewed masked safety data and decided to allow the trial to continue with enrolment of remaining participants into all groups.
The number and proportion of participants with solicited local and systemic reactogenicity events at 2 hours and 7 days after vaccination and throughout full study duration, including serious adverse events.
Immunogenicity in terms of geometric mean titres (GMTs) and four-fold seroconversion rate of neutralising antibodies, from baseline to days 14, 28, 42, 104, and 194.