The Inflation Reduction Act (IRA) will have a significant effect on Medicare Part D, both in terms of beneficiaries’ out-of-pocket (OOP) costs and stakeholder liability within the Part D benefit.

Patient OOP Costs

The IRA Part D redesign provision will lower prescription drug cost-sharing for pharmacy benefit drugs in two phases. First, beginning in 2024, beneficiaries will no longer pay any cost-sharing in the “catastrophic” phase (currently, beneficiaries pay 5 percent cost-sharing). Then, effective January 1, 2025, OOP costs will be capped at $2,000 annually for all Part D beneficiaries, providing the greatest benefit to the 1.5 million enrollees whose OOP costs currently exceed this maximum. 

The IRA also requires Part D sponsors to allow beneficiaries to spread their OOP costs out over the year, known as copay smoothing, by opting into the Medicare Prescription Payment Plan. Once enrolled, beneficiaries will pay $0 at the pharmacy counter and their plans will bill them separately each month.

Part D beneficiaries may also experience lower OOP costs for negotiated drugs if plans were to place these drugs in formulary tiers with lower cost-sharing amounts. However, it is possible that for new drugs, OOP costs could increase. The IRA may incentivize manufacturers to launch new products at higher prices to account for eventual Medicare negotiation and inflationary rebates.

Part D Liability

As Medicare beneficiaries’ cost-sharing in the catastrophic phase goes away, plans will absorb that 5 percent in 2024. In 2025, plans and manufacturers will be responsible for 60 percent and 20 percent respectively of catastrophic spending in Part D, while the amount for which CMS is liable reduces from 80 percent to 20 percent. This increased liability for plans may result in greater utilization management, formulary exclusions, and efforts to extract larger rebates from manufacturers. Plans may also increase premiums as increases to patients’ portion of premiums will be capped at 6 percent per year with taxpayers subsidizing the remainder.

Ready to Learn More? 

Get in touch to schedule a consultation with ADVI Health policy experts for tailored guidance on how Part D redesign may affect your business.


Brenna Raines, MHA
Vice President, Market Access and Policy Strategy

CEO insights

Real analysis from people who’ve been there

Cell and Gene Precision Medicine State Policy

The 2026 Rare Disease Reality

Orphan drugs now represent approximately 20 percent of total prescription spend, and over 52 percent of the cell and gene …

Marc Samuels, JD, MPH
February 26, 2026

AI in the Patient Care Paradigm: Examining Regulatory Challenges to Clinical Adoption  

Artificial intelligence could transform clinical care, but regulatory hurdles slow adoption. Ensuring healthcare AI has adequate policy safeguards is paramount …

Marc Samuels, JD, MPH
December 30, 2025

Precision Medicine

2026 Life Sciences Forecast: AI, Next-Gen Cell & Gene Therapy, and Policy Disruption

In 2026, we expect the healthcare landscape to be defined by technology breakthroughs, market access disruption, and profound policy changes. …

Marc Samuels, JD, MPH
December 16, 2025

Inflation Reduction Act

What HEOR Information Does CMS Need for Drug Price Negotiations Under the IRA?

As the Inflation Reduction Act (IRA) reshapes drug pricing policy in the United States, the Centers for Medicare and Medicaid (CMS) …

December 1, 2025

Cell and Gene

Delivering on CAR T-cell Therapy’s Promise: Policy Solutions for the Next Era of Cancer Care

CAR T-cell therapy offers a groundbreaking treatment option for patients with relapsed or refractory hematologic malignancies, yet access remains severely …

Alicia Silver, MPP
November 21, 2025

Inflation Reduction Act

Real-World Effectiveness vs Clinical Trial Efficacy in Medicare

The Inflation Reduction Act (IRA) has ushered in a new era of drug pricing negotiations in the US. For the …

October 1, 2025

Inflation Reduction Act Pharmaceuticals and Biotech

Why is Medicare Data Central to IRA Negotiations?

The Inflation Reduction Act (IRA), passed in 2022, has transformed the way drug pricing will be managed in the United …

September 10, 2025

Rare Disease

The Unintended Consequences of Drug Pricing Policies on Orphan Drug Development

Rare diseases impact nearly 1 in 10 people in the US and are largely untreated, with 95 percent lacking FDA-approved …

June 23, 2025

Reach out

Own your edge

We don’t just guide the market. We shape it. Map your market access moves with #ADVIIntelligence. Proven advantage. Unmatched partnership.