As the price of specialty drugs continue to rise, employers are desperately seeking to rein in their health care costs. 

According to a recent survey of 487 large employers by Towers Watson and the National Business Group on Health, 80 percent of firms said that design changes to health and pharmacy plans represents the most significant strategic priority over the next three years. 

More than half of employers (53 percent), said they have imposed new restrictions on specialty drugs, such as requiring prior authorization for prescriptions or limiting use based on clinical evidence. By 2018, a full 85 percent of employers plan to have such restrictions in place.