Trial Population:

• 25 received 25ug doses of rSARS-CoV-2
• 29 received 5ug doses of rSARS-CoV-2 + Matrix M1
• 28 received 25ug doses of rSARS-CoV-2 + Matrix M1
• 26 received 25ug doses of rSARS-CoV-2 + Matrix M1 with second vaccination as a single dose placebo
• 23 received a placebo

Safety Outcomes:

• no serious adverse events were reported
• reactogenicity: absent of mild
• only one person had a fever that lasted 1 day

Immunogenicity:

• Day 0: anti-spike IgG GMEUs ranged from 105-116
• Day 21: induced without adjuvant by a factor of at least 10
• Day 28: with adjuvant GMEUs increased by a factor of 8
• Day 35: responses had more than doubled again
• achieved GMFRs that were approx 100x greater than observed with rSARS-CoV-2 alone
• responses in 5ug and 25ug adjuvanted vaccines were similar

Neutralizing antibodies:

• Undetectable before vaccination
• Day 21: GMFRs were approx 5x greater with adjuvant
• Day 35: second vaccine with adjuvant increased 100x than single vaccination without adjuvant
• Approached level that would be observed in hospitalized patients with COIVD-19

Conclusion:

• At day 35, ELISE anti-spike IgG GMEUS and neutralizing antibodies induced by 5ug and 25ug adjuvanted vaccines doses were 4-6x greater
• two dose of 5ug and 25ug with Matrix M1 had similar magnitude response
• strong bias toward Th1 phenotype