A biopharmaceutical company owned by Reynolds American Inc. has gained Food and Drug Administration approval to begin a Phase 1 clinical trial stage in humans for a potential coronavirus vaccine. Kentucky BioProcessing LLC, based on Owensboro, Ky., has been infecting fast-growing tobacco plants this year with a genetically modified coronavirus to see if the plants can produce antibodies for a possible vaccine. A pre-clinical trial testing began in April and was expected to take two months. British American Tobacco Plc, the parent company of Reynolds, said Wednesday the vaccine candidate was approved for its Investigational New Drug application. Enrollment of about 180 adults is expected to begin shortly.