I think the IV route is more likely as the first a

I think the IV route is more likely as the first attempt at treatment, until there's time to do extensive clinical trials to make sure that direct inhalation wouldn't harm patients with already compromised lung function. We've already got an idea from the Phase 1 ABSSSI trial about what a safe dosage is.

Think about how supposedly-safe vaping has injured people, some irreparably (and including some deaths).
That's a cautionary tale.