Roughly speaking, yes, in the sense that the World Health Organization manages what it calls the model essential medicines list for the world. That's the list it believes constitutes the drugs that every human being on earth has a fundamental right to access. That's the starting point.
Clinicians in Toronto, led by Dr. Nav Persaud and his colleagues at St. Michael's Hospital, have Canadianized that list by getting rid of drugs that just aren't needed by wealthy countries like Canada. They've added drugs to that list that we are lucky enough to be able to afford. It still comes up to just about 120 or 130 medicines on the list. It's a reasonable definition of essential medicines for the routine needs of Canadians. It includes things for HIV, rheumatoid arthritis, and some more serious conditions, but most of the medicines in there are the kinds of things that most Canadians might use: drugs to manage cardiovascular care, etc.
Those lists do exist, and Canada could fairly readily try to adapt one of those to whatever budget need we would have, or the budget level we would have if we were to move forward on a program to cover all Canadians.