Medicare Drug Price Rulemaking CMS-4215-P

5:00 p.m. Monday. The clock ran out on the biggest drug pricing fight in years.

Over 11,000 public comments landed in the docket for CMS-4215-P, according to Latham and Watkins’ Drug Pricing Digest. The comment window closed August 17, 2026.

This was not just another regulatory notice. According to PharmaDossier, CMS-4215-P is the agency’s first comprehensive notice-and-comment rulemaking to formally codify the Medicare Drug Price Negotiation Program created by the Inflation Reduction Act of 2022 into binding federal regulations. For the first three negotiated cycles, IPAY 2026, IPAY 2027, and IPAY 2028, CMS ran the entire program through sub-regulatory guidance. No APA rulemaking. No formal public comment. No judicial review under the arbitrary-and-capricious standard.

That era is now over.

🔍 What this rule actually governs:
– Codifies the negotiation framework into 42 CFR Part 429
– Applies to IPAY 2029 and all subsequent cycles
– Targets a final rule in Fall 2026, ahead of the IPAY 2029 selected drug list due February 1, 2027
– Maximum Fair Prices for IPAY 2029 drugs would take effect January 1, 2029

Four major stakeholder coalitions showed up, and they are not aligned.

Industry, led by PhRMA, is fighting hard against CMS’s proposal to aggregate subcutaneous hyaluronidase co-formulations with their reference active moiety under a single drug unit. They argue it chills lifecycle innovation.

Hospitals, led by the AHA, want mandatory point-of-sale Maximum Fair Price effectuation. Their concern is real. A rebate-and-refund model creates cash-flow burdens and, critically, sets a precedent for converting 340B discounts to a rebate model too.

Health economists aligned with Brookings support the aggregation rule, arguing it closes statutory evasion loopholes. They also back trimming the published ranked list of negotiation-eligible drugs from 50 to 30.

Patient advocates want negotiated discounts to flow directly to patient cost-sharing at the dispensing counter, not disappear into a rebate workflow.

💡 Here is what most people are missing.

Now that this is formal regulation under 42 CFR, every policy choice CMS makes in the final rule is subject to direct judicial review under the APA’s arbitrary-and-capricious standard. That is a completely different legal posture than guidance documents. Manufacturers know this. That is exactly why they are litigating, and why the D.C. Circuit’s recent activity on the Teva case matters so much right now.

This rulemaking is the architecture that will govern Medicare drug pricing for years. The fight over IPAY 2029 is really a fight over the permanent legal structure of the entire program.

For anyone building in oncology, cardiology, or any other high-cost specialty area, the cost structure of your patient population just became a formal regulatory question. The final rule lands this fall. Pay attention.

👉 Follow Jonathan Govette, CEO of Oatmeal Health, for daily healthcare insights on LinkedIn. Deeper dives in The Oatmeal Bite on Substack: https://news.oatmealhealth.com