Key points
- More than 80 peptide drugs have reached the market, for diabetes, cancer, osteoporosis, HIV and chronic pain [1].
- In SELECT, semaglutide was associated with 20% fewer major cardiovascular events in 17,604 adults without diabetes [2].
- At the FDA committee, yes votes rested on access, real demand and gray-market risk: “Our patients want peptides” [5].
- A lesser-known argument from supporters: simple peptides are hard to patent, so no one has an incentive to fund the large trials regulators ask for [6].
US status (October 2026): Status varies by compound, from FDA-approved drugs to peptides with no lawful compounding pathway. See the peptide status tracker.
This series covers both sides
This series has reported alerts, negative trials and FDA criticism. The other direction deserves the same standard. A regulator criticizing the lack of data on a peptide does not mean peptides do not work, or that the people who use or prescribe them are wrong. It means the formal evidence does not exist yet. Your patients have read the supporters’ case. You should know it too.
Peptides are already front-line medicine
Since insulin, more than 80 peptide drugs have reached the market for diabetes, cancer, osteoporosis, multiple sclerosis, HIV and chronic pain [1]. Some of the biggest medical advances of this decade are peptides:
- Semaglutide: in STEP 1, -14.9% body weight at 68 weeks [3]. In SELECT, with 17,604 adults with cardiovascular disease and overweight without diabetes, 20% less cardiovascular death, heart attack or stroke [2].
- Tirzepatide: -20.9% body weight in the SURMOUNT-4 lead-in [4].
- Bremelanotide (PT-141): FDA-approved for acquired, generalized hypoactive sexual desire disorder in premenopausal women [9]. See PT-141 status.
- Elamipretide (SS-31): accelerated approval in 2025 for Barth syndrome [10].
- Tesamorelin: approved. In a pooled analysis of two phase 3 trials with 806 HIV patients with excess abdominal fat, the treatment effect on visceral adipose tissue was -15.4% versus placebo at 26 weeks [11].
- More than 80: peptide drugs approved worldwide [1]
- 20% fewer: major cardiovascular events with semaglutide in SELECT [2]
- 45.6 million: patients reached with one maker’s diabetes and obesity products (Novo Nordisk, end-2025 estimate) [7]
The doctors who voted yes gave four reasons
At the July 2026 FDA committee, a majority voted to add six of the seven peptides reviewed to the 503A list. Emideltide fell short (6 yes, 7 no). The reasons given by several clinicians who voted yes, according to Healio [5]:
- Access: “I think it’s about patient access. That’s where I’m coming from.” And on KPV, for patients “who don’t have any options besides what we have available”.
- Real demand: “Nobody put a finished product on a shelf. We took a decision that patients are already making…” And: “Our patients want peptides.”
- The gray market: “The FDA has zero control over that channel.” One voter cited a patient whose “research-grade” product turned out to be laced with MDMA: “That’s not protecting the American people.”
- An unmet need: for emideltide, “a legitimate role in individualized patient care that FDA products do not fully serve at this time”.
The core reasoning is pragmatic. Patients already use these peptides. If the regulated route bans them, they buy them on the gray market, with no doctor, no pharmacy and no controls. Allowing them in compounding pharmacies with a prescription, they argue, is less risky than pretending they do not exist [5][6]. FDA’s own briefing documents took the opposite view, as covered in What FDA said about peptides in July 2026.
The patent problem explains missing trials
According to McDermott’s analysis, supporters noted that the simple structure of these peptides and their long history of use make them hard to patent, and without a patent there is no commercial incentive to pay for the phase 3 trials a formal approval requires [6]. Supporters also pointed to “long histories of use by licensed practitioners” and said inclusion would allow “greater regulatory scrutiny and standards to minimize the risks associated with the current gray market” [6]. Seen this way, the lack of large trials does not prove a peptide is useless. It may reflect that no one has a business model to study it.
The preclinical signal is real
Critics are right that human trials are missing. Supporters have a point too: the lab signal is not made up. In the most recent systematic review of BPC-157 (35 preclinical studies and 1 clinical study), the peptide was associated with better functional, structural and biomechanical outcomes in animal models of muscle, tendon, ligament and bone injury [12]. Full-length thymosin beta-4 improved severe dry eye in a small phase 2 trial (9 patients) [13]. GHK-Cu was associated with better closure of diabetic ulcers [14]. Kisspeptin-54 triggered oocyte maturation in IVF in 60 women at high risk of ovarian hyperstimulation, and none developed moderate, severe or critical hyperstimulation syndrome [15]. These are signals that justify more study. They do not justify dismissal.
Politics changed too
US Health Secretary Robert F. Kennedy Jr. said publicly: “I’m a big fan of peptides… I’ve used them myself and with really good effect on a couple of injuries” [8]. In April 2026 FDA announced it would remove these peptides from its restrictive list and send them to its advisory committee for review. Critics doubt that review will be rigorous [8].
MDside’s position
We publish the evidence for and against under the same rule: every fact with its source. Peptides are one of the most successful drug classes in modern medicine [1][2]. Many unapproved peptides have real preclinical signals and lack the human trials to confirm them [12][13][14]. Both things are true at once.
A political tailwind and a strong preclinical signal do not change today’s legal status. BPC-157 still has no lawful compounding pathway, and a research use only label does not create one. For the legal frame, see Are peptides legal?.
References
- Muttenthaler M, et al. Trends in peptide drug discovery. Nat Rev Drug Discov. 2021;20(4):309-325. PMID 33536635. Link
- Lincoff AM, et al. Semaglutide and cardiovascular outcomes in obesity without diabetes. N Engl J Med. 2023;389(24):2221-32. PMID 37952131. Link
- Wilding JPH, et al. Once-weekly semaglutide in adults with overweight or obesity. N Engl J Med. 2021;384(11):989-1002. PMID 33567185. Link
- Aronne LJ, et al. Continued treatment with tirzepatide for maintenance of weight reduction in adults with obesity: the SURMOUNT-4 randomized clinical trial. JAMA. 2024;331(1):38-48. PMID 38078870. Link
- Healio. FDA committee recommends looser restrictions for several peptides. 24 July 2026. Link
- McDermott Will & Schulte. Bulk list bound? PCAC backs majority of peptides in two-day public meeting. 27 July 2026. Link
- Novo Nordisk A/S. Form 6-K: Annual report / financial statement 2025 (SEC filing). Link
- Boston Globe. FDA to weigh easing limits on unproven peptides favored by RFK Jr. and other MAHA figures. 15 April 2026. Link
- U.S. Food and Drug Administration. Vyleesi (bremelanotide injection) prescribing information. NDA 210557, 2019. Link
- U.S. Food and Drug Administration. FDA grants accelerated approval to first treatment for Barth syndrome. 19 September 2025. Link
- Falutz J, et al. Effects of tesamorelin (TH9507), a growth hormone-releasing factor analog, in human immunodeficiency virus-infected patients with excess abdominal fat: a pooled analysis of two multicenter, double-blind placebo-controlled phase 3 trials with safety extension data. J Clin Endocrinol Metab. 2010;95(9):4291-304. PMID 20554713. Link
- Vasireddi N, et al. Emerging use of BPC-157 in orthopaedic sports medicine: a systematic review. HSS J. 2025;21(4):485-495. PMID 40756949. Link
- Sosne G, Dunn SP, Kim C. Thymosin β4 significantly improves signs and symptoms of severe dry eye in a phase 2 randomized trial. Cornea. 2015;34(5):491-6. PMID 25826322. Link
- Mulder GD, et al. Enhanced healing of ulcers in patients with diabetes by topical treatment with glycyl-l-histidyl-l-lysine copper. Wound Repair Regen. 1994;2(4):259-69. PMID 17147644. Link
- Abbara A, et al. Efficacy of kisspeptin-54 to trigger oocyte maturation in women at high risk of ovarian hyperstimulation syndrome (OHSS) during in vitro fertilization (IVF) therapy. J Clin Endocrinol Metab. 2015;100(9):3322-31. PMID 26192876. Link
This is general information, not medical or legal advice. Rules vary by state and change. Confirm your own facts with counsel.