You can check MIMS. (http://mims.com/) It's a book that lists all the drug products per pharmacological category and usually they're registered with FDA. A section is dedicated to listing of new molecules or new drug products. Hope this helps.

You may also check the list of FDA approved drugs via the following link:

https://www.centerwatch.com/drug-information/fda-approved-drugs/therapeutic-areas

FDA also publishes an yearly data of approved drugs on "fda.gov" (i.e. the official website) but that will be year oriented and so mixed therapeutic categories will be found.

Thanks so much!

So there is no way to get the list of approved drugs categorised according to pharmacological action?

You can also check the "Orange Book" published by USFDA, which lists approved drug products. This allows search by active ingredients, proprietary names, dosage form, applicant etc.

All above answers are helpful even if you find it unresolved better to Visit the FDA official web site for updated information