In a move that promises to reshape the financial landscape of American healthcare, the Centers for Medicare & Medicaid Services (CMS) released a transformative proposed rule on Thursday. The 2027 Hospital Outpatient Prospective Payment System (OPPS) and Ambulatory Surgical Center (ASC) rule targets two of the most contentious pillars of hospital reimbursement: the 340B drug discount program and the practice of site-neutral payments.
Under the leadership of CMS Administrator Dr. Mehmet Oz, the agency is signaling an aggressive push toward what it defines as "clinically appropriate" and "value-based" care. By slashing payments for 340B-acquired drugs and expanding site-neutrality to include specific imaging services, the Trump administration is seeking to curtail what it characterizes as bloated spending, even as industry leaders warn of catastrophic consequences for the nation’s safety-net providers.
The Core Proposals: Aligning Reimbursement with Acquisition Costs
At the heart of the 2027 rule is a fundamental revaluation of how Medicare pays for drugs administered in hospital outpatient departments. For years, the 340B program has allowed hospitals serving vulnerable, low-income populations to purchase outpatient drugs at significant discounts from manufacturers. However, Medicare has historically reimbursed these hospitals based on the average sales price (ASP) plus a 6% margin.
The CMS contends that this spread—where hospitals buy low and are reimbursed at a much higher, standardized rate—has created a "perverse incentive" that inflates costs for both the Medicare program and elderly beneficiaries.
The 340B Pivot
The proposed regulation seeks to shift reimbursement for 340B drugs to the ASP minus 33.4%. CMS officials estimate that this adjustment alone would reduce total Medicare drug spending by $5.7 billion in 2027. Furthermore, the agency projects that beneficiaries would see approximately $1.15 billion in savings on out-of-pocket drug costs in the first year alone.
Because the Medicare outpatient payment system is legally mandated to be budget-neutral, the money saved by cutting 340B payments will be redistributed to increase base rates for non-drug outpatient services. This effectively creates a financial windfall for for-profit health systems and non-340B facilities, which will see their reimbursement rates rise while safety-net hospitals face a direct reduction in revenue.
A Chronology of Conflict: The 340B Legal Battleground
The current proposal is not the first attempt by the executive branch to curb 340B payments, and it arrives with the memory of a significant legal defeat still fresh in the minds of regulators.
- 2017: The CMS attempted to lower 340B reimbursement rates to ASP minus 22.5%. This policy became a flashpoint for years of litigation.
- 2022: The U.S. Supreme Court struck down the 2017 rule, ruling that the Department of Health and Human Services (HHS) acted unlawfully because it had not conducted a formal survey of hospital acquisition costs prior to finalizing the payment cuts.
- 2023-2024: Following the Supreme Court ruling, the government was forced to initiate a massive repayment program to cover the funds withheld from hospitals during the interim years.
- 2025: The Trump administration attempted to introduce a rebate-based model for 340B, which was eventually scrapped following intense industry pushback and concerns over administrative overreach.
- 2026 (Present): Armed with a new, comprehensive survey of hospital drug acquisition costs, the CMS believes it has satisfied the Supreme Court’s legal requirements. By demonstrating that beneficiary cost-sharing sometimes exceeded the actual price hospitals paid for 340B drugs, the agency is attempting to build a bulletproof justification for the new cuts.
Supporting Data and Financial Implications
The 2027 rule is not merely a reduction in drug spending; it is a multifaceted attempt to restructure the outpatient economy.
Expanding Site-Neutrality
The CMS is continuing its push to eliminate the "site-of-service" price gap. Currently, hospital outpatient departments (HOPDs) often receive higher reimbursement rates than freestanding physician offices or ambulatory surgical centers for the exact same procedures. This disparity has been a primary driver of hospital consolidation, as large systems purchase independent clinics to capitalize on the higher reimbursement rates of a hospital-based designation.
The new rule targets imaging services without contrast, proposing to align the payments between hospital outpatient settings and independent physician offices. CMS expects this to reduce Medicare Part B expenditures by roughly $260 million in its first year.
The Inpatient-Only List
In a move that aligns with broader efforts to transition care to lower-cost settings, the CMS is continuing its three-year phase-out of the "inpatient-only" list. In 2027, the agency proposes to remove 638 services from this list, effectively mandating that these procedures be moved to outpatient or ambulatory surgical settings.
Official Responses and Industry Backlash
The reaction from the hospital sector has been swift and uniformly critical. Advocacy groups, particularly those representing safety-net hospitals, argue that the CMS is failing to account for the actual costs of providing care in complex urban and rural environments.
"The proposed OPPS rule from CMS takes an axe to critical funding that supports essential hospitals without concern for how it will affect the patients they serve," stated Jennifer DeCubellis, President and CEO of America’s Essential Hospitals. She and other leaders argue that the 340B discounts are not "windfalls" but are essential subsidies that allow hospitals to provide trauma care, mental health services, and outreach programs in medically underserved areas.
In contrast, CMS Administrator Dr. Mehmet Oz defended the proposal as a necessary correction. "This proposed rule focuses squarely on patient affordability by strengthening our utilization management tools, aligning drug payments with actual acquisition costs, and removing site-of-care disparities that have unnecessarily driven up costs for millions of seniors," Oz said in a statement.
Broader Policy Agendas: Transparency and Oversight
Beyond the high-dollar cuts to drug payments, the 2027 rule introduces several regulatory adjustments aimed at tightening administrative control over the outpatient sector.
The Price Transparency RFI
The Trump administration has maintained a laser focus on hospital price transparency since the inception of the 2021 mandates. Despite these requirements, many hospitals continue to use opaque, algorithmic data displays that are largely unreadable to the average consumer. The 2027 rule includes a Request for Information (RFI) to determine how the agency can standardize reporting, force the use of machine-readable formats, and ensure that patients are presented with "consumer-facing" price displays that provide actual dollar amounts rather than vague estimates.
Prior Authorization: The Botox Crackdown
In a move that caught many by surprise, the CMS is implementing new prior authorization requirements for eight botulinum toxin injection codes. The agency claims that the volume of these injections—used for migraines and cosmetic purposes—has surged without adequate clinical justification. By requiring prior authorization, the CMS intends to curb what it perceives as an epidemic of over-utilization in the outpatient setting.
Strengthening EMTALA Enforcement
Finally, the rule proposes to grant additional inspection authority to hospital accrediting organizations (AOs). Currently, over 80% of U.S. hospitals rely on AOs for their operational standards. By allowing these organizations to assess compliance with the Emergency Medical Treatment and Labor Act (EMTALA)—the law governing emergency screening and stabilization—the CMS hopes to streamline oversight and reduce the burden of duplicative state-level investigations.
Conclusion: The Path Ahead
The release of the 2027 OPPS rule marks a significant escalation in the struggle between the federal government and the hospital industry. While the CMS presents the changes as a victory for beneficiary affordability and clinical efficiency, providers view the rules as a direct threat to their financial viability.
As the industry prepares to submit formal comments during the upcoming notice-and-comment period, legal analysts suggest that the battle over 340B is far from over. With the Supreme Court’s 2022 precedent looming, the ultimate fate of these payment cuts will likely be determined in federal courtrooms rather than in the halls of the CMS. For now, hospitals are left to scramble, modeling the financial impact of a 2.4% outpatient pay increase against the massive, looming reductions in drug reimbursements and the operational shifts required by an ever-expanding site-neutrality mandate.
