The drug industry is riddled with rebates to hide the actual cost. PBMs use the rebates in exchange for access on their formulary. Other rebates or charge backs administered through the wholesaler reduce the cost for a particular contract to a particular customer. The actual cost for the VA is a mystery as this article demonstrates.

Read more in this article from StatNews.com https://www.statnews.com/2017/10/19/drug-costs-ohio-issue-2/