TY - JOUR
T1 - Safety and immunogenicity of SpikoGen®, an Advax-CpG55.2-adjuvanted SARS-CoV-2 spike protein vaccine
T2 - a phase 2 randomized placebo-controlled trial in both seropositive and seronegative populations
AU - Tabarsi, Payam
AU - Anjidani, Nassim
AU - Shahpari, Ramin
AU - Mardani, Masoud
AU - Sabzvari, Araz
AU - Yazdani, Babak
AU - Roshanzamir, Khashayar
AU - Bayatani, Behnam
AU - Taheri, Ali
AU - Petrovsky, Nikolai
AU - Li, Lei
AU - Barati, Saghar
PY - 2022/9
Y1 - 2022/9
N2 - Objective: We aimed to investigate the immunogenicity and safety of SpikoGen®, a subunit COVID-19 vaccine composed of a recombinant prefusion-stabilized SARS-CoV-2 spike protein combined with the Advax-CpG55.2™ adjuvant, in seronegative and seropositive populations as primary vaccination. Methods: This randomized, placebo-controlled, double-blind phase 2 trial was conducted on 400 participants randomized 3:1 to receive two doses of 25 μg of SpikoGen® 3 weeks apart or the placebo. The primary safety outcomes were the incidence of solicited adverse events up to 7 days after each dose and unsolicited adverse events up to 28 days after the second dose. The primary immunogenicity outcomes were seroconversion against the S1 protein and the geometric mean concentration of S1 antibodies by days 21 and 35. Results: The SpikoGen® vaccine was well tolerated and no serious adverse events were recorded. The most common solicited adverse events were injection site pain and fatigue, largely graded as mild and transient. By day 35 (2 weeks post second dose), the seroconversion rate against S1 was 63.55 (95% CI: 57.81–69.01) in the SpikoGen® group versus 7.23 (95% CI: 2.7–15.07) in the placebo group. The geometric mean concentration of S1 antibodies was 29.12 (95% CI: 24.32–34.87) in the SpikoGen® group versus 5.53 (95% CI: 4.39–6.97) in the placebo group. Previously infected seropositive volunteers showed a large SARS-CoV-2 humoral response after a single SpikoGen® dose. Discussion: SpikoGen® had an acceptable safety profile and induced promising humoral and cellular immune responses against SARS-CoV-2.
AB - Objective: We aimed to investigate the immunogenicity and safety of SpikoGen®, a subunit COVID-19 vaccine composed of a recombinant prefusion-stabilized SARS-CoV-2 spike protein combined with the Advax-CpG55.2™ adjuvant, in seronegative and seropositive populations as primary vaccination. Methods: This randomized, placebo-controlled, double-blind phase 2 trial was conducted on 400 participants randomized 3:1 to receive two doses of 25 μg of SpikoGen® 3 weeks apart or the placebo. The primary safety outcomes were the incidence of solicited adverse events up to 7 days after each dose and unsolicited adverse events up to 28 days after the second dose. The primary immunogenicity outcomes were seroconversion against the S1 protein and the geometric mean concentration of S1 antibodies by days 21 and 35. Results: The SpikoGen® vaccine was well tolerated and no serious adverse events were recorded. The most common solicited adverse events were injection site pain and fatigue, largely graded as mild and transient. By day 35 (2 weeks post second dose), the seroconversion rate against S1 was 63.55 (95% CI: 57.81–69.01) in the SpikoGen® group versus 7.23 (95% CI: 2.7–15.07) in the placebo group. The geometric mean concentration of S1 antibodies was 29.12 (95% CI: 24.32–34.87) in the SpikoGen® group versus 5.53 (95% CI: 4.39–6.97) in the placebo group. Previously infected seropositive volunteers showed a large SARS-CoV-2 humoral response after a single SpikoGen® dose. Discussion: SpikoGen® had an acceptable safety profile and induced promising humoral and cellular immune responses against SARS-CoV-2.
KW - Advax-CpG
KW - COVID-19
KW - Phase 2
KW - SARS-CoV-2
KW - SpikoGen
KW - Subunit protein vaccine
UR - http://www.scopus.com/inward/record.url?scp=85130544282&partnerID=8YFLogxK
U2 - 10.1016/j.cmi.2022.04.004
DO - 10.1016/j.cmi.2022.04.004
M3 - Article
C2 - 35436611
AN - SCOPUS:85130544282
SN - 1198-743X
VL - 28
SP - 1263
EP - 1271
JO - CLINICAL MICROBIOLOGY AND INFECTION
JF - CLINICAL MICROBIOLOGY AND INFECTION
IS - 9
ER -