Your fellow islander Alan Cassels from UVic has written on the topic of hypertension drugs. His book with Ray Moynihan refers to UBC's "Therapeutic Initiative". You'll find a paper on hypertension here: http://ti.ubc.ca/en/TherapeuticsLetters (I think it's the second link...).

There might be details about that specific drug there, but I have not checked out the details.