FDA: New Guidelines for Peptide Generics

United States: On July 28, 2026, the U.S. Food and Drug Administration (FDA) published 17 revised draft Product-Specific Guidances (PSGs) for peptide products and simultaneously withdrew the 2021 guidance on synthetic peptides. For anyone interested in peptides, this is an important signal: the market for generic peptides such as semaglutide and tirzepatide is becoming clearer from a regulatory standpoint - and this also affects the quality and safety standards that can be used as a reference.

The key points at a glance

• On July 28, 2026, the FDA published 17 revised draft guidances for generic peptide products, intended to facilitate the development of therapeutically equivalent generics.
• The 2021 guidance on synthetic peptides was withdrawn because it no longer reflects the current state of science; a revision is planned for 2026.
• Injectable peptides for obesity, type 2 diabetes, osteoporosis, and macular degeneration are primarily affected - including GLP-1 agents such as semaglutide and tirzepatide.
• The new guidances specify how manufacturers must identify peptide impurities at levels of 0.10% or higher - an important quality benchmark.

What are Product-Specific Guidances and why are they important?

Product-Specific Guidances are FDA guidances that show manufacturers how to develop and test generic versions of a specific drug in order to obtain approval. They describe the requirements for quality, bioequivalence, and therapeutic equivalence. According to the FDA (2026), the revised PSGs are intended to reflect the agency's current thinking and recommendations on the development of therapeutically equivalent generic peptide drug products.^[2]

This is relevant for peptide users because these guidances indirectly influence the quality standards for generic peptides. If you are interested in generic GLP-1 products, you can assume that the FDA is imposing stricter requirements for purity and identity - this is a safeguard against low-quality products.

Which peptides are affected?

The FDA does not name the specific active ingredients in the announcement, but the therapeutic areas include obesity, type 2 diabetes, osteoporosis, and macular degeneration.^[3] From the context, it is clear that GLP-1 receptor agonists such as semaglutide (31 amino acids) and tirzepatide (39 amino acids) are among the affected peptides.^[1] Since these active ingredients have fewer than 40 amino acids, they are not considered biologics and can be approved as generics via the ANDA pathway.^[4]

GLP-1 is a peptide hormone that regulates blood sugar levels and promotes satiety. Semaglutide and tirzepatide are synthetic copies of this hormone, used as medications for type 2 diabetes and obesity. The new guidances therefore concern exactly the active ingredients that also play a major role in the gray market.

What changes compared to the 2021 guidance?

The FDA has withdrawn the 2021 guidance "ANDAs for Certain Highly Purified Synthetic Peptide Drug Products That Refer to Listed Drugs of rDNA Origin" because it no longer reflects the current state of science.^[2] The 2021 guidance addressed the assessment of the "sameness" of the higher-order structure of peptides - that is, the three-dimensional folding that is crucial for their effect.^[6]

The exact substantive changes are not evident in detail from the available sources, but the FDA emphasizes that the new PSGs reflect the current state of science. This means: stricter requirements for analytics, particularly in the identification of peptide impurities. According to an FDA guidance, ANDA applicants must identify any peptide impurity at 0.10% or more of the active ingredient.^[9]

What does this mean for the market and for you?

The new guidances come against the backdrop of an expected sharp increase in peptide therapeutics, led by GLP-1 receptor agonists.^[6] Two generic liraglutide products have already been approved (December 2024 and August 2025), showing that the approval pathway for peptides works.^[5] The new PSGs could facilitate the development of more generics, which could lead to lower prices and better availability in the long term.

For users, this means: if you are interested in generic peptides, look for products manufactured according to these stricter standards. The FDA has also clarified that compounded semaglutide and tirzepatide products are no longer available as of May 22, 2025, as the shortage situation has ended.^[7] This closes an important source for cheaper alternatives.

This is a positive signal for greater regulatory clarity - but also a warning: the market for peptide generics is becoming more tightly controlled, and products from the gray market could increasingly come under scrutiny from authorities. More on this can be found in the article on the EMA guidance for synthetic peptides and on the FDA strategy against unregulated peptides.

For more on quality criteria for peptides, see the Peptide Library or use the Injection Calculator for correct application. If you are unsure how to vet providers, the page Protection when ordering can help.

Not medical advice: This article is for informational purposes only and does not replace professional medical advice.