Every test on a human being requires FDA approval beforehand. I can easily see why they would put company resources on existing clinical trial right now on diseases that can be shown to improve (or not) quickly, rather than those that take a long time until results are known (like cancer).

If resources are unlimited and you have a ton of employes, sure, go ahead and run a bunch of clinical trials all at the same time, at various phases. If you're trying to use resources to get the best result for a partnership, you don't change horses in midstream -- you continue pushing with the clinical trials that are closer to Phase 3.