Medicaid formularies cover extended-release buprenorphine more than others, study finds

Fewer than half of commercial and one-fifth of Medicare Advantage formularies covered extended-release buprenorphine in 2021, a new study found.

The study, published in the latest issue of Health Affairs, examined Medicaid, Medicare Advantage and commercial payer formulary files. It aimed to track insurance-imposed utilization restrictions and other requirements for covering the medication for opioid use disorder (OUD) from 2017 to 2021. 

Despite a general trend of decreasing prior authorization requirements and quantity limits over time, prior authorization was still much more common for extended- than immediate-release buprenorphine, the study found. Almost all formularies across payers covered at least one immediate-release buprenorphine product during the time period studied.

Unlike immediate-release buprenorphine, extended-release is a once-monthly injection administered by a clinician, which could help address medication adherence and misuse concerns, the study authors wrote. 

A higher share of Medicaid formularies (83%) covered extended-release buprenorphine than Medicare Advantage (19%) and commercial (46%), though more than a third still required prior authorization. Though people with OUD primarily use Medicaid, rates of OUD have risen across many populations.

“Medicare beneficiaries’ access to OUD treatment is critical, as rates of older Americans with OUD have risen in recent years,” the study’s authors wrote.

In the U.S., 2021 was a record-breaking year for opioid overdose deaths. Buprenorphine, which is widely seen as one of the gold standards for OUD treatment and is associated with a 50% decrease in mortality among those with OUD, is underutilized in the U.S., the study noted. Insurance restrictions are frequently cited as barriers to prescribing the medication. 

While quantity limits for immediate-release were rare among Medicaid and commercial payers, about half of Medicare Advantage formularies placed limits on the tablets. Unlike immediate-release buprenorphine, no generic version of extended-release exists, so payers may have a stronger incentive to impose utilization restrictions to save on costs, the study suggested. 

Reducing access barriers to extended-release is important because it carries no misuse risk, and evidence suggests most patients prefer extended-release, the study concluded. Expanding access to extended-release buprenorphine could also help address issues around low pharmacy stock at independent and rural pharmacies.

State regulators could require payers to cover extended-release, and researchers and policymakers should monitor coverage and utilization barriers across all payer types, the authors suggested.