I mean, that's pretty routine. But I don't believe that, at least from the U.S. side, I don't believe there was any grant written, that I'm on, where we proposed to do experiments of furin cleavage sites. Yet, the reason why I became less interested in it was we discovered that if you add trypsin exogenously to the cultures, viruses that you couldn't culture could now be cultured. And that's because cleavage of S1/S2 boundary, cleavage of the spike, is essential for the virus to get into the cell. And if it can't be cleaved, the virus replicates exceptionally poorly, if at all. But if you add trypsin, which is a protease, into the media, you could take viruses that you couldn't culture and now you could culture them. So to some extent I was more interested in being able to have a range of coronaviruses. So, for example, remdisivir was tested in about 12 or 13 coronaviruses, including many different sarbecos, from Clade 1 and Clade 2. So we had a really good idea that it would work against an unknown, and it turned out to be effective against SARS21 coronavirus-2 when used appropriately.