Good question. The toxicity study would be used to test the toxicity of the combination of the already approved FDA drugs. I do not exactly know. I would expect they run the rodent study for the length of the therapy, then maybe a week or 2 longer to response after the drug moves through the animal and to test accordingly.
But because it's the same drug being ingested consistently every day, they could shorten it. We know the protocol lasts 42-45 days to achieve the optimal results. But those in control of the study may not require nearly that long to test for toxicity of the drug therapy. So, it's hard to know. I would venture to say the length of the protocol or close to it. 4-8 weeks. Just my guess.