Utilization management in Medicare Part D has become more restrictive over the last decade, even when compared to Medicare Advantage prescription drug plans, according to a new study.
The study, conducted by researchers at the University of Southern California and Blaylock Health Economics and published this week in Health Affairs, found an increase across multiple types of utilization management, including prior authorization, step therapy and formulary exclusions, between 2011 and 2020.
On average, 31.9% of drugs were restricted in some fashion in 2011, which grew to 44.4% by 2020, according to the study. By the end of the study window, 44.7% of formularies restricted brand-name-only drugs.
"Increasing reliance on formulary exclusions, a particularly blunt tool for restricting patients’ access to therapies, is especially striking, as it prevents all but the few who successfully appeal or can afford to pay out of pocket from getting a restricted medication if it is prescribed by their physician," the researchers wrote.
The researchers note that at the same time formularies have grown more restrictive, enrollment in Part D has grown significantly. Membership in these plans grew by 56% between 2011 and 2020, from 33.2 million enrollees to 52 million.
The study found just how restrictive access to a certain drug was varied based on the cost and the availability of generic options. For example, in 2020, just 16.7% of generic-available drugs with a price of $100 or less were excluded from formularies or subject to prior auth or step therapy. By comparison, 59.5% of generic-available drugs with a price of $1,000 or more were restricted.
For brand-name-only products, 15.8% of those with prices of $100 or less were restricted, while that jumped to 83.7% for drugs costing $1,000 or more.
The researchers said the trend merits further study, as they did not uncover whether the ultimate goal is to manage costs or to boost returns.
"Our analysis could not clearly determine whether these practices are used to ensure that care is delivered cost-effectively or whether these restrictions benefit pharmacy benefit managers’ bottom lines while harming patients," they wrote.