In a letter sent Thursday, Nov. 17th, Sanders and Representative Elijah Cummings (D-Md.) referred to a pattern in which prices for insulin sold by Eli Lilly, Sanofi, and Novo Nordisk often rose in tandem over several years. The lawmakers expressed concern that the drug companies may have been coordinating their pricing and, as a result, driving up the cost for millions of Americans, including both patients and taxpayers.  Their letter cited a recent analysis that found the cost of insulin more than tripled — from $231 to $736 a year per patient — between 2002 and 2013. Meanwhile, since 2009, the lawmakers pointed to 13 instances in which the prices of Sanofi and Novo Nordisk insulin brands rose in lockstep. They said Lilly did the same. The practice is known as shadow pricing.  The original insulin patent expired 75 years ago. Drug makers in general argue that they have to raise prices in order to give substantial rebates to pharmacy benefit managers, who are the middlemen that negotiate with health plans. Each company has stated that they set prices for the life-saving medicines independently.  — Bloomberg News Nov. 2016  (See comments from David Kliff –  Diabetic Investor – Item 4.)