Buprenorphine Coverage in the Medicare Part D Program for 2007 to 2018

Abstract

This study uses Medicare Part D prescription drug plan formulary files to characterize changes in coverage of buprenorphine and buprenorphine-naloxone for opioid use disorder in 2007, 2012, and 2018.

Buprenorphine is critical for expanding treatment availability to individuals with an opioid use disorder (OUD) because it can be prescribed by primary care clinicians.¹ However, buprenorphine is underused, and a contributing factor may be insurance company cost-control measures, such as prior authorization or step therapy. These policies, which require prescribers to obtain insurance approval prior to dispensing, may delay or disrupt treatment for patients with OUD vulnerable to relapse.

For the more than 300 000 Medicare beneficiaries with OUD in 2013 (approximately 14% of 2.1 million US individuals with OUD),^1,2 access to buprenorphine is important because methadone maintenance has historically not been a covered benefit.³ We evaluated trends in buprenorphine coverage in the Medicare Part D program.

Methods

We analyzed Medicare Part D prescription drug plan formulary files from January 2007, 2012, and 2018 to characterize changes in coverage of buprenorphine products for OUD. Formulary files contain coverage details, including prior authorization and step therapy requirements, for both stand-alone and Medicare Advantage Part D plans. Using plan enrollment as weights, we estimated coverage and restrictions for each buprenorphine product using Stata version 15.1 (StataCorp). We used the Cochrane-Armitage trend test to evaluate changes in weighted proportions over time with 2-tailed P < .05 indicating statistical significance.

We excluded plans with fewer than 11 enrollees because their data are suppressed. In 2016, 98% of Medicare Part D buprenorphine use was brand-name buprenorphine-naloxone sublingual films (70%), generic buprenorphine-naloxone sublingual tablets (16%), or generic buprenorphine sublingual tablets (12%).⁴ Therefore, we focused on brand-name and generic versions of these products. We also estimated the number of plans covering any buprenorphine product without restrictions. For context, we calculated the cost for a 30-day supply of the 8-mg strength (target dose, 16 mg/d) using the wholesale acquisition cost for each year.⁵ Also, we evaluated the same policies for the most frequently prescribed long-acting (extended-release morphine sulfate) and short-acting (hydrocodone or acetaminophen) opioids in the Medicare program.⁴

Results

The proportion of plans covering brand-name buprenorphine-naloxone sublingual tablets or films declined from all plans offering coverage to 74% (95% CI, 70%-77%) of plans in 2018 (Table; P < .001). Generic buprenorphine-naloxone tablets, which were approved in 2013, were covered by 73% (95% CI, 69%-77%) of plans in 2018. Brand-name buprenorphine tablets, which were discontinued in 2011, were covered by 94% (95% CI, 92%-96%) of plans in 2007. Generic buprenorphine tablets, which were first available in 2010, were covered by all plans in 2018.

Table. Medicare Part D Plans Covering Buprenorphine Products, Extended-Release Morphine Sulfate, and Hydrocodone or Acetaminophen, 2007-2018.

Part D Plansa	2007 (n = 3281)			2012 (n = 2633)			2018 (n = 2873)			P Valuee
	Cost, $b	No. of Plansc	Weighted % (95% CI)d	Cost, $b	No. of Plansc	Weighted % (95% CI)d	Cost, $b	No. of Plansc	Weighted % (95% CI)d
Brand-Name Buprenorphine-Naloxone Sublingual Tablet or Film
Coverage	267 (tablet)	3212	100 (100-100)	481 (tablet)	1656	65 (61-70)	489 (film)	2119	74 (70-77)	<.001
Prior authorizationf		921	16 (13-19)		955	71 (66-76)		1147	58 (53-63)	<.001
Step therapyg		0	0		0	0		0	0
Covered and available without restrictions		2291	84 (81-86)		701	19 (16-22)		972	31 (27-35)	<.001
Generic Buprenorphine-Naloxone Sublingual Tablet (Approved in 2013)
Coverage							406	2162	73 (69-77)
Prior authorizationf								1121	57 (52-62)
Step therapyg								19	1 (0-1)
Covered and available without restrictions								1022	31 (27-35)
Brand-Name Buprenorphine Sublingual Tablet (Discontinued in 2011)
Coverage	337	3101	94 (92-96)
Prior authorizationf		839	13 (11-16)
Step therapyg		0	0
Covered and available without restrictions		2262	82 (78-85)
Generic Buprenorphine Sublingual Tablet (Approved in 2010)
Coverage				279	2218	83 (79-87)	80	2871	100 (100-100)	<.001
Prior authorizationf					1454	76 (72-80)		1724	66 (62-70)	<.001
Step therapyg					0	0		0	0
Covered and available without restrictions					764	20 (17-23)		1147	34 (30-38)	<.001
≥1 Buprenorphine Productsh
Covered without prior authorization or step therapy		2497	89 (87-91)		810	20 (17-24)		1235	35 (31-39)	<.001
Generic Extended-Release Morphine Sulfate
Coverage		3058	94 (92-96)		2632	100 (99-100)		2871	100 (100-100)	<.001
Prior authorizationf		0	0		0	0		325	7 (6-9)	<.001
Step therapyg		0	0		2	0		0	0	<.001
Covered and available without restrictions		3058	94 (92-96)		2630	100 (99-100)		2546	93 (91-94)	<.001
Generic Hydrocodone or Acetaminophen
Coverage		3193	99 (98-99)		2627	100 (99-100)		2871	100 (100-100)	<.001
Prior authorizationf		0	0		0	0		180	3 (2-5)	<.001
Step therapyg		0	0		0	0		0	0
Covered and available without restrictions		3193	99 (98-99)		2627	100 (99-100)		2691	97 (95-97)	<.001

^aIncludes stand-alone prescription drug plans and Medicare Advantage plans that had more than 10 enrollees (the data from plans with ≤10 enrollees are suppressed).

^bWholesale acquisition cost (eg, for 60 units of 8-mg buprenorphine).

^cUnweighted number of plans with more than 10 enrollees.

^dWeighted by plan enrollment.

^eCalculated using the Cochrane-Armitage trend test for weighted proportions.

^fRequires prior approval for reimbursement.

^gRequires treatment failure or intolerance to preferred product for reimbursement.

^hIncludes all buprenorphine products indicated for opioid use disorder.

Among plans offering coverage, prior authorization requirements for brand-name buprenorphine-naloxone tablets or films increased from 16% (95% CI, 13%-19%) of plans in 2007 to 58% (95% CI, 53%-63%) in 2018 (P < .001). Prior authorization was required by 57% (95% CI, 52%-62%) of plans in 2018 covering generic buprenorphine-naloxone tablets. Prior authorization was required by 13% (95% CI, 11%-16%) of plans in 2007 covering brand-name buprenorphine sublingual tablets. Although generic buprenorphine had the lowest cost ($80) in 2018, 66% (95% CI, 62%-70%) of plans required prior authorization. Step therapy was required in 0% to 1% of plans.

The proportion of plans covering any buprenorphine product without restriction declined from 89% (95% CI, 87%-91%) in 2007 to 35% (95% CI, 31%-39%) in 2018 (P < .001). By comparison, 93% to 100% of plans covered the most frequently used prescription opioid analgesics without coverage restrictions during the study period.

Discussion

Although buprenorphine coverage in Medicare Part D plans was high throughout the study period, prior authorization requirements increased. In 2018, 65% of plans restricted coverage for all forms of buprenorphine. The reasons for restrictions on buprenorphine might reflect inaccurate perceptions of drug risk, societal norms related to the stigma of addiction, or financial considerations.

Historically, payers use prior authorization and step therapy policies to control costs; however, two-thirds of plans had prior authorization policies on lower-cost generic buprenorphine in 2018. Limitations of this study include a lack of data on approval criteria for restrictions and rebates paid to plans.

Effective in 2020, the Substance Use-Disorder Prevention That Promotes Opioid Recovery and Treatment (SUPPORT) for Patients and Communities Act will expand Medicare coverage to include methadone treatment through opioid treatment programs.³ However, access to OUD treatment for Medicare beneficiaries could immediately be improved by requiring Part D plans to remove coverage-related barriers.

Section Editor: Jody W. Zylke, MD, Deputy Editor.