Several anti-parasitic medications are well know for being antivirals and having other uses. Oxyclozanide is known to fight MRSA, and Niclosamide was once thought to be a breakthrough Zika drug.

We used to know it was common, when in a medical outbreak emergency, that you screen all the FDA approved medications first, as this is the fastest first step that could bring a result. Sometimes, it matters who says something more than what they say, I've learned.