That $13.1 billion is what the provinces are spending on their public drug plans. They do receive the Canada health transfer. Those transfers are meant for many more health services than just pharmaceuticals. They enter the provinces like general revenues, and they can spend them as they want. Conceivably, a portion of that transfer is paying for some of this drug expenditure, but we can't say how much.
On October 17th, 2017. See this statement in context.