Some studies said chloroquine works in vitro against influenza viruses, and that is promising. But they could not replicate it in vivo yet: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4941887 Maybe a study with HCQ instead of just chloroquine and with zinc supplements will show success. The problem is that nobody can earn money with HCQ, so there is no incentive for expensive studies.