They would be like therapeutic equivalents to treat the same thing. There are probably about six categories of medications to treat uncomplicated hypertension, so I would put the one that is the most cost-effective in the value basket and put the others in a copay basket. You can actually make a conditional listing on top of that, as suggested here, where the conditional listing is that “you show me that this person has that or has failed this kind of treatment before and therefore I'm going to pay for it”.
That has administrative overhead on it in terms of someone having to manage that program. Payers in the U.S., for example, have a lot of those kinds of programs, and they change them practically weekly.
It's really to say this: can we at least get our value out of a system by giving free medication for absolutely essential diseases and the most cost-effective drug to treat that condition in that category? Yes, we agree that others could equally work, but we have something that will work and we want to pay and negotiate the best price for it.