1.
Efficacy of the adjuvanted subunit protein COVID-19 vaccine, SCB-2019: a phase 2 and 3 multicentre, double-blind, randomised, placebo-controlled trial.
Bravo, L, Smolenov, I, Han, HH, Li, P, Hosain, R, Rockhold, F, Clemens, SAC, Roa, C, Borja-Tabora, C, Quinsaat, A, et al
Lancet (London, England). 2022;(10323):461-472
-
-
Free full text
-
Abstract
BACKGROUND A range of safe and effective vaccines against SARS CoV 2 are needed to address the COVID 19 pandemic. We aimed to assess the safety and efficacy of the COVID-19 vaccine SCB-2019. METHODS This ongoing phase 2 and 3 double-blind, placebo-controlled trial was done in adults aged 18 years and older who were in good health or with a stable chronic health condition, at 31 sites in five countries (Belgium, Brazil, Colombia, Philippines, and South Africa). The participants were randomly assigned 1:1 using a centralised internet randomisation system to receive two 0·5 mL intramuscular doses of SCB-2019 (30 μg, adjuvanted with 1·50 mg CpG-1018 and 0·75 mg alum) or placebo (0·9% sodium chloride for injection supplied in 10 mL ampoules) 21 days apart. All study staff and participants were masked, but vaccine administrators were not. Primary endpoints were vaccine efficacy, measured by RT-PCR-confirmed COVID-19 of any severity with onset from 14 days after the second dose in baseline SARS-CoV-2 seronegative participants (the per-protocol population), and the safety and solicited local and systemic adverse events in the phase 2 subset. This study is registered on EudraCT (2020-004272-17) and ClinicalTrials.gov (NCT04672395). FINDINGS 30 174 participants were enrolled from March 24, 2021, until the cutoff date of Aug 10, 2021, of whom 30 128 received their first assigned vaccine (n=15 064) or a placebo injection (n=15 064). The per-protocol population consisted of 12 355 baseline SARS-CoV-2-naive participants (6251 vaccinees and 6104 placebo recipients). Most exclusions (13 389 [44·4%]) were because of seropositivity at baseline. There were 207 confirmed per-protocol cases of COVID-19 at 14 days after the second dose, 52 vaccinees versus 155 placebo recipients, and an overall vaccine efficacy against any severity COVID-19 of 67·2% (95·72% CI 54·3-76·8), 83·7% (97·86% CI 55·9-95·4) against moderate-to-severe COVID-19, and 100% (97·86% CI 25·3-100·0) against severe COVID-19. All COVID-19 cases were due to virus variants; vaccine efficacy against any severity COVID-19 due to the three predominant variants was 78·7% (95% CI 57·3-90·4) for delta, 91·8% (44·9-99·8) for gamma, and 58·6% (13·3-81·5) for mu. No safety issues emerged in the follow-up period for the efficacy analysis (median of 82 days [IQR 63-103]). The vaccine elicited higher rates of mainly mild-to-moderate injection site pain than the placebo after the first (35·7% [287 of 803] vs 10·3% [81 of 786]) and second (26·9% [189 of 702] vs 7·4% [52 of 699]) doses, but the rates of other solicited local and systemic adverse events were similar between the groups. INTERPRETATION Two doses of SCB-2019 vaccine plus CpG and alum provides notable protection against the entire severity spectrum of COVID-19 caused by circulating SAR-CoV-2 viruses, including the predominating delta variant. FUNDING Clover Biopharmaceuticals and the Coalition for Epidemic Preparedness Innovations.
2.
Immunogenicity and safety of an adjuvanted inactivated polio vaccine, IPV-Al, compared to standard IPV: A phase 3 observer-blinded, randomised, controlled trial in infants vaccinated at 6, 10, 14 weeks and 9 months of age.
Bravo, LC, Carlos, JC, Gatchalian, SR, Montellano, MEB, Tabora, CFCB, Thierry-Carstensen, B, Tingskov, PN, Sørensen, C, Wachmann, H, Bandyopadhyay, AS, et al
Vaccine. 2020;(3):530-538
Abstract
BACKGROUND A dose-sparing inactivated polio vaccine (IPV-Al), obtained by adsorption of inactivated virus to an aluminium hydroxide adjuvant, can help mitigate global supply and the cost constraints of IPV. The objective of this trial was to demonstrate the non-inferiority of IPV-Al to standard IPV. METHODS This phase 3, observer-blinded, randomised, controlled trial was conducted at 5 investigational sites in the Philippines. Infants not previously vaccinated with any polio vaccines were randomised to receive three IPV-Al (n = 502) or IPV vaccinations (n = 500) at 6, 10 and 14 weeks of age plus a booster vaccination at 9 months. The primary endpoint was type-specific seroconversion, defined as an antibody titre ≥4-fold higher than the estimated maternal antibody titre and a titre ≥8, one month after the primary vaccination series. RESULTS Seroconversion rates following primary vaccination with IPV-Al (483 infants in the per-protocol analysis set) or IPV (478 infants) were: polio type 1, 97.1% versus 99.0%; type 2, 94.2% versus 99.0%; and type 3, 98.3% versus 99.6%. IPV-Al was non-inferior to IPV, as the lower 95% confidence limits of the treatment differences were above the predefined -10%-point limit: type 1, -1.85% (-3.85; -0.05); type 2, -4.75% (-7.28; -2.52); type 3, -1.24 (-2.84; 0.13). The booster effect (geometric mean titre (GMT) post-booster / GMT pre-booster) was: type 1, 63 versus 43; type 2, 54 versus 47; type 3, 112 versus 80. IPV-Al was well tolerated with a safety profile comparable to that of IPV. Serious adverse events were recorded for 29 infants (5.8%, 37 events) in the IPV-Al group compared to 28 (5.6%, 48 events) in the IPV group. CONCLUSION Non-inferiority of IPV-Al to IPV with respect to seroconversion was confirmed and a robust booster response was demonstrated. Both vaccines had a similar safety profile. ClinicalTrials.gov identifier: NCT03032419.