In the new study, the scientists investigated 26 of the coronavirus’s 29 genes, which direct production of the viral proteins. The researchers found 332 human proteins targeted by the coronavirus.

Some viral proteins seemed to target just one human protein; other viral proteins are capable of targeting a dozen human cellular proteins.

The researchers sought drugs that also latch onto the human proteins that the coronavirus seems to need to enter and replicate in human cells. The team eventually identified 24 drugs approved by the Food and Drug Administration to treat such seemingly unrelated diseases as cancer, Parkinson’s disease and hypertension.

On the list were such unexpected candidates as haloperidol, used to treat schizophrenia, and metformin, taken by people with Type 2 diabetes.