China's Clover says its COVID booster shot candidate lifts antibody against Omicron

Clover Biopharmaceuticals

27/06/2022 11:44

BEIJING, June 27 (Reuters) - China's Clover
Biopharmaceuticals  2197.HK  said on Monday a booster shot of
its COVID-19 vaccine candidate significantly increased antibody
response against the Omicron coronavirus variant from levels
seen after two primary shots. 
    A third dose of its vaccine candidate SCB-2019 resulted in a
19-fold increase in neutralising antibody levels against the
Omicron BA.2 subvariant from pre-booster levels, Clover said in
a filing to the Hong Kong stock exchange. 
    The booster shot also elicited a 12-fold rise in the
neutralising antibody level against the BA.1 subvariant, the
company said, citing preliminary analysis without providing
detailed readings. 
    The results came from a cohort of participants, who had no
natural infection of the coronavirus and showed waning
antibodies before the booster, in a clinical trial that has
enrolled 3,755 participants in Brazil, the Philippines and
Columbia, Clover said. 
    SCB-2019, which is backed by the Coalition for Epidemic
Preparedness Innovation (CEPI), has yet to be approved for
commercial use. 
    Antibody-based readings differ from a vaccine's efficacy, a
rate that reflects how well it could lower the risk of COVID
disease or death.
    Data from a large clinical trial conducted before the spread
of Omicron showed SCB-2019 was 67% effective against symptomatic
COVID-19 of any degree of severity and 79% against the Delta
variant.  urn:newsml:reuters.com:*:nL1N2QO0TI
    Clover did not discuss cell-based responses elicited by the
booster, another important part of human immune system different
from antibody-based responses.  
    Clover is also testing a separate candidate SCB-2020S in an
early stage trial and working on a bivalent vaccine candidate
targeting variants of concern including Omicron.

 (Reporting by Roxanne Liu and Ryan Woo; Editing by Miyoung Kim,
Robert Birsel)
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