Unfortunately there is not a clear segmentation here between what NIH funds and what ultimately becomes the product available on the market. NIH often fund basic research, while others pick that up and attempt to make a drug out of it. This is super simplifying it, but it's a complex process with lots of organizations and many funding sources.

In addition to public funding of NIH research, it takes a commercial company (pharma) well beyond $1 billion to get one successful drug on the market.

https://en.wikipedia.org/wiki/Cost_of_drug_development