The article doesn't go into it, but the actual paper[1] states that this vaccine has "has previously been reported to be immunogenic and protective against pneu

The article doesn't go into it, but the actual paper[1] states that this vaccine has "has previously been reported to be immunogenic and protective against pneumonia in a rhesus macaque challenge model", and cites to [2]. [1] https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31604-4/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6... [2] https://www.biorxiv.org/content/10.1101/2020.05.13.093195v1 https://www.biorxiv.org/content/10.1101/2020.05.13.093195v1