Efficacy of the adjuvanted subunit protein COVID-19 vaccine, SCB-2019: A phase 2 and 3 multicenter, double-blind, randomized, placebo-controlled trial

The LancetBravo L, Smolenov I, Han HH, et al. | January 25, 2022


Given the necessity for a range of safe and effective vaccines against SARS CoV 2 to address the COVID 19 pandemic, researchers herein examined the safety and efficacy of the COVID-19 vaccine SCB-2019.

  • In this ongoing phase 2 and 3 double-blind, placebo-controlled trial, adults aged 18 years and older were enrolled at 31 sites in five countries (Belgium, Brazil, Colombia, Philippines, and South Africa) and were assigned 1:1 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.

  • There was enrollment of 30,174 participants; of whom 30,128 were administered their first assigned vaccine (n = 15,064) or a placebo injection (n = 15,064).

  • A total of 207 confirmed per-protocol cases of COVID-19 were recorded 14 days after the second dose, 52 vaccines vs 155 placebo recipients.

  • The overall vaccine efficacy against any severity COVID-19 was 67·2%, 83·7% against moderate-to-severe COVID-19, and 100% against severe COVID-19.

  • Overall findings revealed induction of notable protection by two doses of SCB-2019 vaccine plus CpG and alum against the entire severity spectrum of COVID-19 caused by circulating SAR-CoV-2 viruses, including the predominating delta variant.

Read the full article on The Lancet