"This study provides the first in vivo evidence that zinc sulfate in combination with hydroxychloroquine may play a role in therapeutic management for COVID-19."

https://www.sciencedirect.com/science/article/pii/S030698772...

"we hypothesize that CQ/HCQ plus zinc supplementation may be more effective in reducing COVID-19 morbidity and mortality than CQ or HCQ in monotherapy."

https://www.researchgate.net/profile/Mujeeb_Shittu4/publicat... roquine-against-SARS-CoV-2-may-require-Zinc-additives-A-better-synergy-for-future-COVID-19-clinical-trials.pdf

"We seek to draw the attention of the scientific community to the possibility of drastically reducing the effects of the vi-rus on the affected patients and improving clinical tri-als outcome through the synergistic action of zinc and chloroquine"

https://www.researchgate.net/profile/Rishad_Ahmed2/publicati...

"Thirdly, hydroxychloroquine acts as an ionophoric agent for Zinc ions and thus increases the influx of Zinc ions into the cytoplasm of host target cells regardless whether the host target cells are infected or not [10]. Zinc ions adhere to the RNA dependent RNA polymerase enzyme of the virus and stops COVID-19 polymerization intracellularly."

We do need follow up and repeated clinical trials.