FDA gives the public until July 30, 2026 to comment on 503B compounding of semaglutide and tirzepatide

Federal health regulators have added 30 days to the public's chance to weigh in on a proposal that would keep semaglutide, tirzepatide and liraglutide off the list of bulk ingredients that large compounding facilities are allowed to use. The new deadline is July 30, 2026, according to a notice published June 26, 2026 ^[1][2].

The proposal itself appeared May 1, 2026 with a 60-day comment window. It asks whether the three active pharmaceutical ingredients have a clinical need for outsourcing facilities to use in compounding — the 503B Bulks List ^[2].

FDA received a request for 60 additional days. The requester said the first window did not leave enough time for a meaningful response, and that more time would let interested parties produce "rigorous and comprehensive comments" on "complex clinical, public health, and legal issues," including patient safety and access to high-quality medications ^[2]. The agency granted half of what was asked. It wrote that a 30-day extension "appropriately balances allowing adequate time for interested persons to submit comments with avoiding significant delay of Agency action on these important issues" ^[2].

Electronic comments go through regulations.gov and must arrive by 11:59 p.m. Eastern Time on July 30, 2026. Comments sent by mail, hand delivery or courier count as timely if they arrive by that date, and FDA said late filings "will not be considered" ^[1][2]. The docket number is FDA-2018-N-3240, and the notice runs at 91 FR 38719 ^[1][2]. According to the agency, the comments "will inform FDA's final determination whether to include these substances on the 503B Bulks List" ^[2].

Federal law splits compounding into two categories. A 503A pharmacy prepares a drug for one patient against one prescription. A 503B outsourcing facility produces in bulk without patient-specific prescriptions and distributes at scale — the setup behind many compounded GLP-1 subscription services ^[3].

Why it matters for patients

July 30 is a filing deadline, not a date when the rules change. What FDA has issued so far is a proposal, and it carries no legal weight unless the agency finalizes it ^[2][3].

If a final rule mirrors the proposal, 503B facilities would have to stop making these three ingredients in bulk, which would tighten supply through that channel ^[3]. The notice does not spell out what would happen to 503A pharmacies that compound for individual patients ^[2].

FDA-approved versions of the two main molecules are already on the market. Semaglutide is sold as Ozempic and Wegovy; tirzepatide as Mounjaro and Zepbound. Both are approved for weight management ^[3]. A pill form of Wegovy cleared the agency on December 22, 2025 and costs $149 a month without insurance, according to the clinic Med Matrix, which follows the compounded GLP-1 market ^[3].

The same clinic's review cites FDA data showing more than 455 adverse event reports tied to compounded semaglutide and more than 320 tied to compounded tirzepatide as of early 2025, many of them dosing errors made when patients measured doses from multidose vials ^[3]. It also counts three rounds of FDA warning letters to telehealth sellers since September 2025 — about 80 that month, roughly 30 in March 2026, and 25 during the week of June 15, 2026 — over claims that a compounded product is the "same" as the approved drug and over marketing that leaves out the pharmacy that made it ^[3].

What happens next

FDA reviews the comments after July 30, 2026, then issues a final determination on whether the three substances belong on the 503B Bulks List. No date for that decision has been published ^[2][3]. Until it comes, the legal footing for 503B compounding of semaglutide, tirzepatide and liraglutide is unchanged ^[3].