In addition to biology, pharmacology, and organic chemistry coursework at university level, since computers are used so much in the pharmacological fields -- with Dr Paul Janssen of piritramide, loperamide, dextromoramide, fentanyl & haloperidol fame being one of the early adopters -- I would propose going a little beyond the mathematics requirement and at least 18 credit-hours of programming and computer science courses as well. Note also that the international languages of chemical and other engineering are English, German, and Japanese, and there is a lot of literature in the latter two which has not yet been translated into English.
Some people have a knack for this kind of thing and turns out to not be such an extreme slog. For example, Dr Vincent Dole of Nyswander & Dole fame crammed seven semesters of biology and chemistry into one summer and got into medical school that September.
Drugs testing would vary from place to place depending on custom and local privacy laws -- I am not sure if there is anywhere on earth that drugs testing is as big a thing as it is in the US .. .
And/or, if capital can be obtained and you have at least six or eight like-minded individuals to help, starting one's own pharmaceutical company may be a possibility -- and you can eat the mistakes.
If one is a pharmacology student at university and/or inventor, I gather that, to cite one example, if you have a 350 kilo safe in a laboratory of some type, one could apply for a licence to handle controlled substances -- DEA Form 223 I think it is called in the states, and then there are local permits and licences required too. That licence is for Schedules II to V and I think that Schedule I authorisation is in the licences that laboratories and manufacturers have.