17 Peptides. Category 2. Compounding Over.
Between October 2023 and February 2024, the FDA classified 17 popular wellness peptides as Category 2 bulk drug substances, a designation meaning they present "significant safety concerns" and cannot be compounded by licensed pharmacies for human use. The list included the two most widely used peptides in the longevity and regenerative medicine space: BPC-157 (Body Protection Compound-157) and TB-500 (Thymosin Beta-4). Also hit: CJC-1295, Ipamorelin, AOD-9604, and MK-677, among others.1,2
The reaction from the wellness community was volcanic. Practitioners who had built entire clinic revenue streams around peptide therapies lost their product supply overnight. Patients who swore by BPC-157 for injury recovery, gut healing, and chronic pain found themselves cut off from what they believed was a life-changing treatment. The narrative that emerged, almost immediately, was pharmaceutical conspiracy: big pharma wanted these compounds for itself and used the FDA to eliminate the competition.1
The Department of Justice then made things worse. Tailor Made Compounding LLC, one of the largest peptide compounding pharmacies in the country, pleaded guilty to distributing unapproved drugs including BPC-157 and forfeited $1.79 million. This was a criminal prosecution, not a regulatory slap. The message was unmistakable: the era of compounded wellness peptides was over.3
FDA's stated rationale: Insufficient human safety data. Immunogenicity risks (the body may mount immune responses against injected peptides). Characterization and impurity concerns in compounded formulations. Lack of documented historical use in compounding prior to commercial marketing.1,2
What Category 2 means: 503A pharmacies (traditional compounding) cannot use these bulk substances. 503B outsourcing facilities cannot compound them. No FDA-approved product exists for any of these peptides. Any product marketed as these peptides for human use is, by definition, an unapproved new drug.
September 2024 update: Five peptides, including BPC-157, were removed from Category 2 for further review by the Pharmacy Compounding Advisory Committee (PCAC). This does not mean they were approved. They were moved to a different queue. As of early 2026, none have been placed in Category 1 (approved for compounding).4
The Part Nobody Wants to Hear
Here is where The Corneum parts company with both the FDA's critics and the FDA itself. The angry longevity community frames this as government overreach suppressing effective treatments. The FDA frames it as protecting consumers from unsafe products. Both narratives obscure a more fundamental problem: the clinical evidence for these peptides in humans barely exists.
Fewer than 30 total humans have been studied across all published BPC-157 research. The only Phase I safety trial (42 volunteers, 2015) was cancelled and results were never published. No public explanation was given.5,6
The "Wolverine Peptide" With No Human Proof
BPC-157 is a synthetic pentadecapeptide derived from a sequence found in human gastric juice. In animal models, it does remarkable things: accelerates Achilles tendon healing, protects gastric mucosa, reduces inflammation, promotes angiogenesis, improves muscle crush injury recovery, and appears to protect nearly every organ system tested. The preclinical literature is unusually broad and consistently positive. Nobody disputes the animal data.5,6,7
The human data consists of three published pilot studies totaling fewer than 30 subjects, none with randomized controls, all from private clinics that sell BPC-157 injections. The largest, a retrospective case series of 12 people with chronic knee pain, had no standardized pain scoring, no imaging, no blinding, and no control group. The clinic that administered the injections conducted the follow-up. Seven of twelve reported relief lasting more than six months, which, as one reviewer noted, tells us approximately nothing given that chronic knee pain often improves with time, attention, and the powerful expectation that comes with paying for a novel injection.5,6
Scope: Screened 544 BPC-157 articles from 1993–2024. Included 36 studies (35 preclinical, 1 clinical). Evaluated mechanism, musculoskeletal effects, metabolism, safety.5
Conclusion: "Despite its growing popularity among athletes and its wide availability through non-regulated sources, there is minimal human data available. Until well-designed clinical trials are conducted, BPC-157 should be considered investigational, and its use approached with caution."
The cancelled trial: In 2015, PharmaCotherapia registered a Phase I clinical trial (NCT02637284) with 42 healthy volunteers. It was the first rigorous human safety study. The study was completed, but in 2016 the researchers cancelled submission of results. No explanation was ever published. This is a significant red flag.6
The history of medicine is littered with compounds that worked brilliantly in rodents and failed spectacularly in humans. Rat physiology isn't human physiology.
Clinical review, BPC-157 evidence assessment, 2025Zero Human Trials. Zero.
TB-500 is a synthetic fragment of Thymosin Beta-4, a naturally occurring protein involved in tissue repair, cell migration, and wound healing. The parent protein (Thymosin Beta-4) actually entered formal pharmaceutical development. A Phase II clinical trial was completed in 2009 for wound healing. Over fifteen years later, the results have never been published, a red flag suggesting the data was not favorable.8
TB-500 itself has zero published human clinical trials. Not one. Not a pilot study. Not a case series. Nothing. Its safety profile in humans is completely unknown. A 2024 study raised the additional concern that TB-500 may not even be the active compound, that its healing activity might come from a smaller breakdown fragment. People are injecting a substance whose direct biological activity remains genuinely mysterious even to the researchers studying it.8
Research Chemicals, Bitcoin, and a Prayer
With compounding pharmacies shut out, the peptide market has migrated almost entirely to the grey market. Online vendors sell BPC-157 and TB-500 labeled "for research purposes only" and "not for human consumption" while marketing with dosing guides, healing testimonials, and anti-aging language that makes the intended use unmistakable. The FDA's "intended use doctrine" sees through this labeling fiction: if the marketing implies human use, the label is legally void regardless of the disclaimer.3,9
Purity Crisis
Research-grade peptides operate with zero pharmaceutical quality control. A systematic review found that 12–58% of ergo-nutritional supplements are contaminated with undisclosed substances. Research peptides have even less oversight. When you inject a vial from an overseas vendor, you are trusting an unregulated lab with no legal accountability.5
The Cancer Question
BPC-157 and TB-500 both promote angiogenesis (new blood vessel formation). This is the mechanism claimed to accelerate healing. It is also the mechanism that feeds tumors. No human study has evaluated long-term cancer risk. The theoretical concern is not dismissed by any researcher in the field. Long-term safety data simply does not exist.6,8
Legal Exposure
BPC-157 is Category 2 (prohibited from compounding). It is WADA-banned under S0 Unapproved Substances. The U.S. DoD prohibits military use. Tailor Made Compounding forfeited $1.79M in a DOJ prosecution. Any physician prescribing these outside a formal IND-sanctioned trial is operating outside the standard of care.1,3
What the Animal Data Actually Shows
The preclinical evidence for BPC-157 is genuinely promising across multiple organ systems and injury types. This is not dismissed. It is precisely why the field needs human clinical trials, not a grey market that substitutes anecdote for evidence and Joe Rogan clips for peer review.5,7
Everyone Is Wrong. The Trials Need to Happen.
This is not a story about the FDA protecting you from dangerous drugs. The FDA classified these peptides as Category 2 based on insufficient safety data and theoretical concerns, not demonstrated harm. The honest statement from the FDA's own review acknowledged it "lacks sufficient information" to know whether these peptides would harm humans. Banning something because you don't have data is a regulatory choice, not a scientific conclusion.
But this is also not a story about pharmaceutical conspiracy crushing miracle cures. BPC-157, the most studied peptide on this list, has been tested in fewer than 30 humans total. It has zero randomized controlled trials. Its only Phase I safety study was cancelled without explanation. TB-500 has zero human trials of any kind. The people injecting these compounds are not taking "treatments the FDA doesn't want you to have." They are taking untested substances whose safety and efficacy in humans has never been established by any standard that would pass basic scientific scrutiny.
Both sides are filling a vacuum. The FDA filled the vacuum with prohibition. The longevity community filled it with anecdotes, testimonials, and conspiracy theories. The actual answer is clinical trials, which neither side seems particularly interested in conducting. The animal data for BPC-157 is compelling enough to justify rigorous human investigation. The fact that this investigation has not happened, and that the one trial that started was cancelled without explanation, is the real scandal of the peptide story.
Until those trials happen, people injecting grey-market peptides are participating in an uncontrolled, unmonitored, self-funded experiment with compounds of unknown purity, unknown dose-response characteristics, and unknown long-term safety profiles. That is their right. But calling it "medicine" insults every compound that actually survived the process of proving it works.
BPC-157 has 544 studies and fewer than 30 human subjects across all published research. TB-500 has zero human trials. The FDA banned them from compounding based on insufficient data, not demonstrated harm. The grey market sells them with zero quality control and a disclaimer that fools nobody. The animal data is genuinely promising. The human data does not exist. Somewhere between "pharmaceutical conspiracy" and "dangerous snake oil" is the truth: these are untested compounds that deserve real clinical trials, not a $39 billion unregulated market built on rat studies and podcasts.
Sources
- FDA Category 2 Bulk Drug Substance classifications. 2023–2024. 17 peptides classified including BPC-157, TB-500, CJC-1295, Ipamorelin, AOD-9604, MK-677. Cited: immunogenicity, impurity concerns, insufficient human safety data.
- Holt Law. Deep dive: regulatory status of popular compounded peptides. 2025. 503A/503B framework, Category 1 vs 2 analysis, legal consequences for practitioners.
- DOJ prosecution. Tailor Made Compounding LLC. Guilty plea for distributing unapproved drugs including BPC-157. $1.79M forfeiture. FDA warning letters to online retailers.
- FDA. September 2024 removal of 5 peptides from Category 2 for PCAC review. Including BPC-157 (pentadecapeptide), TA-1, CJC-1295, Ipamorelin, Selank. Not approved; moved to further review queue.
- Vasireddi et al. Emerging use of BPC-157 in orthopaedic sports medicine: a systematic review. HSS J / Am J Sports Med. 2025. 544 articles screened, 36 included (35 preclinical, 1 clinical). Conclusion: minimal human data, should be considered investigational.
- Peptide-DB. Every BPC-157 human trial up to 2026. 3 published pilot studies, <30 total subjects, 0 RCTs. Phase I trial (NCT02637284, n=42) cancelled 2016, results never published.
- Joćwiak M, et al. Multifunctionality and possible medical application of BPC 157. Pharmaceuticals. 2025. Comprehensive review of preclinical effects, mechanism, pleiotropic activity. "Limited but encouraging clinical evidence."
- Clinical review. The peptide gamble: a doctor's warning on BPC-157 and TB-500. 2025. TB-500: zero human trials. Parent protein TB4 Phase II (2009) results never published. Angiogenesis-cancer concern. Conflict of interest in existing BPC-157 case series.
- USADA. BPC-157: experimental peptide creates risk for athletes. 2025. Prohibited under WADA S0. Not approved by any global regulatory authority. "Concerning lack of published clinical trial data."
- Feb 2026 risk analysis. Peptides in clinical practice: enforcement landscape. Category 2 prohibitions, DOJ referrals, state AG enforcement, malpractice liability framework.