Patient demand for peptide therapy is growing faster than most operators realize. Google searches for “Sermorelin” increased over 230 percent in a single year. Thousands of patients are actively looking for accessible peptide programs, and the businesses positioned to meet that demand compliantly are building some of the most durable recurring revenue streams in cash-pay medicine.
The challenge for most operators is regulatory clarity. The FDA’s category system for bulk drug substances determines which peptides can be legally offered today, and the landscape has shifted enough in the past two years that a lot of information online is outdated or incomplete.
This guide covers the basics: what FDA Category 1 means, which peptides fall under it, what compliance actually requires, and how to build a program around the substances that are clearly available today.
Important: This article is for informational purposes only and does not constitute legal or medical advice. Classifications are subject to change. Confirm current status with your pharmacy partner and legal counsel before launching any program.
What the FDA Category System Actually Means
The FDA evaluates bulk drug substances (the active pharmaceutical ingredients used by compounding pharmacies) and assigns them to categories that determine whether they can legally be compounded. Understanding this framework is the starting point for any serious peptide program.
Category 1: Eligible for Compounding
Category 1 substances have sufficient supporting safety information on file for the FDA to permit compounding while its evaluation continues. This is the operative status for building a compliant peptide program today.
When a substance holds Category 1 status:
- A licensed 503A compounding pharmacy can prepare it with a valid, patient-specific prescription
- Licensed prescribers can write prescriptions for compounded formulations
- Compounding pharmacies can include these substances in their active formularies
Category 1 does not mean the substance has cleared full FDA drug approval, which requires clinical trials and a formal New Drug Application. It means the pathway for compliant compounding is open, with appropriate clinical oversight in place.
Category 2: Not Eligible
Category 2 substances are under active FDA evaluation and cannot be legally compounded during the evaluation period. Prescribers cannot obtain compounded Category 2 substances through compliant channels, and compounding pharmacies cannot prepare them.
In recent years, the FDA moved 19 peptides into Category 2, effectively removing them from the market. In February 2026, HHS Secretary Robert F. Kennedy Jr. announced plans to move approximately 14 of those peptides back to Category 1, but the formal rule change had not been published as of the time of this writing. Until it is, Category 2 peptides remain off-limits.
For the full context on the expected reclassification, see our guide to FDA peptide reclassification 2026.
Category 3: Rejected
Category 3 substances have been evaluated and the FDA has determined they should not be used in compounding. This is a final determination and these substances are not available through any compliant compounding pathway.
The Summary
| Category | Status | Can It Be Compounded? |
|---|---|---|
| Category 1 | Eligible, sufficient safety data | Yes, with a valid patient-specific prescription |
| Category 2 | Under evaluation, not currently eligible | No |
| Category 3 | Evaluated and rejected | No |
Source: FDA Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A.
The Category 1 Peptides Most In Demand Today
For operators building programs, the relevant question is not the full regulatory catalog but rather which Category 1 peptides have the strongest patient demand and the clearest clinical use cases. These are the ones showing up in compliant programs consistently.
Sermorelin
Sermorelin is a synthetic peptide that signals the pituitary gland to produce and release growth hormone naturally rather than introducing exogenous growth hormone directly. The FDA originally approved it in 1997 for growth hormone deficiency in children. The manufacturer voluntarily discontinued commercial production in 2008, and the FDA confirmed this was for business reasons rather than safety or efficacy concerns. Sermorelin holds Category 1 status and remains one of the most prescribed peptides in cash-pay medicine.
Common program applications:
- Hormone optimization and men’s health
- Body composition and metabolic support
- Sleep quality and recovery
- Longevity and healthy aging
Patient interest has grown significantly. Searches for Sermorelin increased more than 230 percent from August 2024 to August 2025 according to Google Ads Keyword Planner data, a signal of where consumer demand is heading.
Gonadorelin
Gonadorelin is a synthetic hormone that supports the body’s natural hormonal production cycle. In men’s health programs it is most commonly paired with testosterone replacement therapy to help maintain the body’s own hormonal function during treatment, addressing one of the most common patient concerns about TRT.
Gonadorelin was initially approved for diagnostic testing and fertility applications in the 1980s. Commercial production was discontinued for business and commercial reasons, not safety concerns. It is available for compounding under FDA guidelines for clinical use when prepared according to current USP standards.
Common program applications:
- TRT companion therapy for preserving natural hormonal function
- Men’s health and hormone optimization
- Women’s reproductive health protocols
GHK-Cu (Copper Peptide)
GHK-Cu is a naturally occurring copper peptide with a well-documented role in cellular repair, collagen synthesis, and skin health. It has been studied extensively and holds strong interest from the aesthetics and anti-aging market alongside its clinical uses.
For operators with an aesthetics-adjacent audience, GHK-Cu programs have particularly strong fit. For more detail see our deep dive on GHK-Cu and copper peptide programs.
Common program applications:
- Skin health and aesthetics programs
- Wound healing support
- Collagen and tissue repair
- Anti-aging and longevity protocols
Thymosin Alpha-1
Thymosin Alpha-1 is an immune-modulating peptide with a long history of clinical research. It has been studied as a therapeutic agent in chronic infections, immune deficiencies, and post-viral recovery. Demand for immune optimization programs has remained elevated since the pandemic.
Common program applications:
- Immune support programs
- Chronic infection management support
- Post-viral recovery protocols
- Longevity and immune optimization
See our full guide on Thymosin Alpha-1 programs.
Epitalon
Epitalon is a synthetic tetrapeptide based on the naturally occurring Epithalamin, derived from the pineal gland. It is most commonly associated with anti-aging and longevity research, making it a natural fit for longevity-focused programs and high-end wellness operators.
Common program applications:
- Longevity and anti-aging programs
- Sleep cycle regulation
- Telomere support and cellular health protocols
See our guide on Epitalon longevity programs.
A Note on GLP-1 Receptor Agonists
GLP-1 medications like semaglutide and tirzepatide are frequently grouped with peptide therapy in patient conversations, and many operators offer them alongside peptide programs. However, GLP-1 compounding operates under a separate FDA framework tied to shortage status rather than the Category 1 system. Eligibility requirements for GLP-1 compounding have changed and will continue to evolve.
If you are building a GLP-1 program, confirm current compounding eligibility with your pharmacy partner before launching. Karpa monitors this on an ongoing basis for all platform partners.
Is It Legal? What Compliance Actually Requires
Category 1 designation opens the legal door. What happens inside that door depends on how the program is built.
The Federal Requirements
A compliant Category 1 peptide program requires:
- A valid, patient-specific prescription from a licensed provider in the patient’s state
- A licensed 503A compounding pharmacy meeting USP 797 standards for sterility, potency, and quality
- Human-grade API sourced from FDA-registered manufacturers (not research-grade)
- Documented medical necessity in the patient record
- Informed consent covering the compounded and off-label nature of the therapy
These are federal minimums. State rules add another layer.
State-Level Complexity
Federal Category 1 status does not automatically satisfy every state’s requirements. A few examples of where this matters:
- Some states require synchronous (live video) provider consultations for initial prescriptions rather than asynchronous intake
- Compounding pharmacies must hold licenses in each state where they ship patient-specific medications, meaning not every pharmacy can serve every state
- Prescribing scope varies by provider type and state, so what a nurse practitioner can independently prescribe in one state may require physician oversight in another
For operators building multi-state programs, this is an operational reality that requires a pharmacy partner with broad state licensing and a provider network credentialed appropriately for each state.
Research-Grade vs. Human-Grade API
This distinction matters more than most operators initially realize, and it is where some programs create significant liability.
Research-grade peptide API is not the same as human-grade API. Peptides labeled “for research use only” typically lack the cGMP certification required for human therapeutic use. Using research-grade API in peptide compounding introduces clinical risk to patients and regulatory and legal exposure to the operator and any prescribers involved.
Human-grade API used in compounding must come from FDA-registered facilities following strict current Good Manufacturing Practice guidelines: purity verification, endotoxin testing, detailed certificates of analysis, full material traceability, and rigorous quality control.
When vetting compounding pharmacy partners, one of the most important questions is sourcing. Any legitimate compounding pharmacy should be able to provide documentation of API sourcing from FDA-registered manufacturers.
What This Means for Operators Building Programs
The Category 1 peptides available today represent a clear, compliant opportunity for cash-pay programs. The patient demand is real, it is growing, and the regulatory pathway is established for the right set of substances.
The friction is operational. Building a compliant program from scratch requires:
- Identifying a compounding pharmacy partner with multi-state licensing and verified API sourcing
- Establishing a provider network with credentials appropriate across your patient states
- Creating intake, triage, and informed consent workflows that meet both federal and state requirements
- Monitoring regulatory status ongoing, because classifications and state rules change
Operators who try to piece this together independently spend months on infrastructure before their first patient. Operators who use a platform like Karpa launch in days with the infrastructure already built.
Karpa’s platform provides:
- A 50-state licensed provider network for all prescribing
- Integrations with vetted 503A compounding pharmacies with verified API sourcing
- HIPAA-compliant intake and AI-assisted patient triage
- Pre-built clinical protocols for Category 1 peptide programs
- Ongoing regulatory monitoring so your program stays compliant as the landscape shifts
You build the brand and the patient audience. Karpa handles the clinical and operational infrastructure behind it.
