Clover, Dynavax COVID vaccine shows efficacy against Omicron subvariant BA.5 in trial
Clover Biopharmaceuticals said its COVID-19 vaccine SCB-2019 (CpG 1018/Alum) elicited a robust immune response to Omicron BA.5 subvariant in a phase 2/3 trial, building upon previous results for neutralization against Omicron BA.2.
The Chinese company added that results come from two groups of the global phase 2/3 trial called SPECTRA. In one group 3,755 people were enrolled in Brazil, Colombia, and the Philippines who received SCB-2019 (CpG 1018/Alum) as a homologous third dose in individuals who previously received two doses of SCB-2019. Meanwhile in another group, 14,692 people were enrolled in Belgium, Brazil, Colombia, the Philippines, and South Africa who had prior SARS-CoV-2 infection.
A booster dose of SCB-2019 in people who had received two doses of SCB-2019 previously, showed a robust 12-fold increase against the Omicron BA.5 subvariant, with geometric mean titers (GMTs) of neutralizing antibodies increasing from 35 (pre-booster) to 408 (14 days post-booster), the company said in an Aug. 29 press release.
Clover noted that previously reported results showed that relative to pre-booster levels, a third dose of SCB-2019 exhibited a 19-fold boost in neutralizing antibodies against the Omicron BA.2 subvariant and a 12-fold boost in neutralizing antibodies against Omicron BA.1.
Meanwhile in people with prior COVID infection, two doses of SCB-2019 given three weeks apart, elicited a 61-fold increase in neutralizing antibodies against BA.5, with GMTs increasing from 16 (baseline) to 984 (14 days after second dose). The vaccine also exhibited a 37-fold boost in neutralizing antibodies against the Omicron BA.2 subvariant and a 20-fold boost in neutralizing antibodies against Omicron BA.1 after second dose.
"It builds upon the full breadth of our development of SCB-2019 (CpG 1018/Alum) as a universal booster demonstrating broad neutralization against the most current Omicron lineages and all Variants of Concern to date," said Nicholas Jackson, president of Global Research and Development of Clover.
Earlier in August, the company noted that the vaccine showed efficacy in adolescents in a phase 2/3 trial.
Clover said it was focused on completing regulatory submissions in China, EU and to the World Health Organization for SCB-2019 in H2 2022, while concurrently preparing for its commercialization.
Clover created the COVID vaccine by combining SCB-2019 with Dynavax's (NASDAQ:DVAX) CpG 1018 advanced adjuvant and aluminum hydroxide (alum).
The vaccine development has been funded by the Coalition for Epidemic Preparedness Innovations (CEPI), which has awarded Clover up to $397.4M to enable equitable access to the vaccine candidate.