China’s Clover Biopharmaceuticals has announced its COVID-19 S Trimer vaccine candidate delivered a “strong immune response” in 150 adult and elderly phase 1 trial participants, with pre-publication results to be released soon.

The randomized, placebo-controlled study evaluated the vaccine’s safety, reactogenicity and immunogenicity when combined with an adjuvant from either the UK’s GlaxoSmithKline or Emeryville, Calif.-based Dynavax Technologies to boost the vaccine’s efficacy. With the adjuvants tiered at two different vaccine dosages, antibodies were induced in 100 percent of participants, Clover says.

Clover has planned a global phase 2/3 study evaluating the GlaxoSmithKline adjuvant system for this month, while preparing to launch a separate pivotal trial evaluating the vaccine with Dynavax’s adjuvant to begin in the first half of next year.