By demanding transparency, rejecting rebate-first contracts, and making biosimilars the default choice, advisors and employers can rewrite the rules of the system.

"Retirement savers remain committed to their financial futures by staying the course with their retirement savings," said Sharon Brovelli, president of Workplace Investing at Fidelity Investments.

However, the site is lagging far behind Ro.com — a telehealth services and anti-obesity drug provider — but crushing the Mark Cuban Cost Plus Drug Company's CostPlusDrugs.com site.