Peptides 101

Peptides have become the new frontier of the wellness internet. Five years ago the conversation was about testosterone and SARMs; now it's BPC-157, GLP-1 agonists, melanotan, and an expanding list of research chemicals sold out of Chinese warehouses with reconstitution instructions posted on Reddit. Some of this is real — GLP-1 medications represent the single biggest advance in metabolic medicine in forty years, and their chemistry is a peptide chemistry. Most of the rest is a mixture of plausible biology, underpowered trials, and vendors selling unlabeled powders to men who can't pronounce what they're injecting.

This guide is an attempt to lay out what peptides actually are, which ones have evidence, which ones have only stories, and how to think about them without getting scammed or hurt. It is not a how-to for injecting research chemicals. It is the article I wish someone had handed me the first time I started reading peptide forums and realized half the information was from vendors with usernames ending in numbers.

What peptides actually are

Size, chemistry, and how they differ from traditional drugs

A peptide is a short chain of amino acids. By the usual convention, "peptide" means roughly 2 to 50 amino acids; longer chains are called proteins. The distinction is not chemically sharp — insulin at 51 amino acids is sometimes called a peptide, sometimes a protein — but for practical purposes, peptides are small enough to be synthesized in a lab by solid-phase peptide synthesis and large enough to have the specific folded structure that binds receptors.

Traditional small-molecule drugs are typically 200-500 daltons in molecular weight. Most peptides are 1000-5000 daltons. The size difference matters for several practical reasons:

Peptides are generally destroyed by stomach acid and by proteolytic enzymes in the gut. Oral bioavailability is near zero for most of them. This is why almost every therapeutic peptide is injected, sprayed into the nose, or delivered some other route that bypasses the GI tract.

Peptides are usually highly specific for a single receptor or a small family of receptors, because their three-dimensional shape is precisely what fits into a binding pocket. This is the opposite of small molecules, which often bind to many receptors and produce off-target effects. The specificity is partly why peptides can have surprisingly clean side effect profiles when they work.

Peptides do not cross the blood-brain barrier easily unless they are specifically designed to, or unless they are small enough to slip through. A peptide injected subcutaneously usually produces peripheral effects, not central ones, unless it has a specific CNS-penetrant design.

Peptides have short half-lives in the blood — minutes to hours for native sequences. Therapeutic peptides are almost always chemically modified to extend half-life: added fatty acid tails for albumin binding (semaglutide, liraglutide), PEG groups, non-natural amino acids that resist enzymatic degradation.

Natural peptide signaling (why the body uses them)

Most hormones are peptides. Insulin, glucagon, GLP-1, GIP, PYY, ghrelin, leptin, oxytocin, vasopressin, growth hormone, GHRH, ACTH, TSH, FSH, LH, CRH, TRH, and many more. The body uses peptides as signaling molecules because they are cheap to encode (one gene per peptide), can be made in specific tissues, and can be rapidly cleared, allowing for tight temporal control over signals.

The therapeutic logic of peptide drugs is usually to replace, mimic, or block one of these natural signals. GLP-1 agonists mimic GLP-1, a gut-derived hormone that signals fullness and lowers blood glucose. Semaglutide is basically GLP-1 with modifications that make it last a week instead of minutes. The drug is not doing anything the body doesn't do on its own; it is doing it harder and longer.

This is a useful frame for evaluating claims. A peptide drug that claims to do something the body does not do through any known signaling pathway is either a novel discovery or vaporware; the second is much more common.

Why they're mostly injected

Oral bioavailability of typical peptides is 0-1%. The GI tract exists partly to break down proteins into their constituent amino acids, and it does not care whether the protein is your dinner or a thousand-dollar peptide. Nearly all therapeutic peptides are administered by:

Subcutaneous injection. The most common route. A small insulin-syringe needle into the fat pad of the abdomen, thigh, or upper arm. Absorption takes 30 minutes to several hours depending on formulation.

Intramuscular injection. Used for some peptides requiring faster or more complete absorption, or where SC irritation is a problem. Larger needle, deeper injection.

Intranasal spray. Works for a small subset of peptides — oxytocin, PT-141, some of the Russian nootropic peptides like Selank and Semax. Only small, specifically-designed peptides cross nasal mucosa efficiently.

Oral formulations (rare). Rybelsus is an oral semaglutide that uses an absorption enhancer (SNAC) to produce about 1% oral bioavailability — enough to be useful at high doses. This kind of formulation is expensive to develop and works only for specific peptides.

The injection requirement is part of what limits peptide therapy and part of what makes the gray-market trade so dangerous. Sterility, dosing accuracy, and storage all become the user's problem, and most users are not trained to handle them.

The categories, honestly

Growth hormone secretagogues (GHRP, CJC-1295, Ipamorelin)

Growth hormone secretagogues are peptides that stimulate the pituitary to release its own growth hormone. They fall into two families that are usually combined:

GHRH analogs (CJC-1295, Tesamorelin, Sermorelin) mimic growth-hormone-releasing hormone from the hypothalamus. They bind the GHRH receptor on somatotrophs and drive GH release.

Ghrelin mimetics / GH secretagogues (GHRP-2, GHRP-6, Ipamorelin, Hexarelin, MK-677) bind the ghrelin receptor (GHSR-1a) and drive GH release through a different pathway. They also affect appetite (GHRP-6 notably increases hunger; ipamorelin less so).

The two classes combined synergistically; a common protocol is CJC-1295 plus ipamorelin.

What the claims are. Increased muscle mass, reduced fat, improved recovery, better sleep, anti-aging effects.

What the evidence shows. GH secretagogues do raise endogenous GH and IGF-1 in a dose-dependent way, and the elevations are real. The question is whether those elevations in otherwise healthy adults produce the claimed downstream effects.

Tesamorelin is FDA-approved for HIV-associated lipodystrophy and does reduce visceral fat in that population. MK-677 (ibutamoren, oral, technically not a peptide but often grouped with them) has been studied in frail elderly and shows modest lean mass gains with meaningful side effects (fluid retention, worsened insulin sensitivity, occasional edema). The rest of the class has very limited randomized evidence in healthy adults for the body composition claims.

The honest summary. If you have clinically low GH or a specific indication, some of these have evidence. In a healthy 35-year-old trying to optimize, the effect size is probably small relative to sleep and training, and the side effects (water retention, carpal tunnel-like symptoms from tissue swelling, blunting of natural GH pulsatility, and potentially worsened insulin sensitivity) are real. Not nothing, not magic.

Healing / tissue repair (BPC-157, TB-500)

The most heavily hyped category in the gray-market peptide space, and the one with the largest gap between claims and evidence in humans.

BPC-157 (Body Protection Compound 157) is a 15-amino-acid synthetic peptide derived from a sequence found in human gastric juice. In rodent studies, it accelerates healing of tendon injuries, muscle tears, bone fractures, gut damage, and blood vessel injury. The rodent data are genuinely impressive — dozens of studies from multiple labs, with consistent results across many injury models.

TB-500 is a synthetic fragment of thymosin beta-4, a naturally occurring protein involved in tissue repair and angiogenesis. Also shows tissue-healing effects in animal models, including cardiac tissue after infarction.

What the evidence shows in humans. Almost nothing. BPC-157 has not been in a single well-powered randomized controlled trial in humans for any indication as of this writing. The rodent data are from daily injections at doses that are easy to achieve in small animals and uncertain to translate to humans. There are no long-term safety data. Oral BPC-157 is marketed despite essentially no human bioavailability data, and the rodent evidence was with injection in most cases.

The honest summary. BPC-157 might work in humans for tendon and soft-tissue healing. It might also not. The biology is plausible and the rodent data are unusually consistent for a supplement-grade compound. But "plausible and unproven in humans" is a specific category, and paying $200 for a vial of it and injecting it into an injured shoulder is paying for a hypothesis. If you are an elite athlete in the final 1% of recovery optimization, maybe the bet is worth it. If you are a 40-year-old with chronic tennis elbow, see a physical therapist first and don't skip ahead.

Metabolic (Semaglutide, Tirzepatide, Retatrutide)

This is the category where peptide medicine has its strongest evidence and its biggest current clinical impact.

Semaglutide (Ozempic, Wegovy, Rybelsus) is a GLP-1 receptor agonist. Approved for type 2 diabetes and obesity. In the STEP trials, 2.4 mg weekly produced roughly 15% body weight loss over 68 weeks, with substantial improvements in blood pressure, lipids, and HbA1c. The cardiovascular outcomes trials (SELECT, 2023) showed a 20% reduction in major adverse cardiovascular events in overweight/obese adults without diabetes. This is a big result.

Tirzepatide (Mounjaro, Zepbound) is a dual agonist hitting both GLP-1 and GIP receptors. In the SURMOUNT trials, the highest dose produced roughly 22.5% weight loss over 72 weeks — higher than semaglutide. Evidence is accumulating for metabolic and cardiovascular benefits similar to or better than semaglutide.

Retatrutide is a triple agonist (GLP-1, GIP, glucagon) in late-stage trials. Phase 2 data showed ~24% weight loss over 48 weeks. Not yet approved.

What the evidence shows. Unusually strong data across multiple large trials, with consistent magnitude of effect, clear cardiovascular benefit, and a mechanism that is well-understood. GLP-1 agonists are not a fad; they are a genuine medical advance that will change obesity medicine for at least a decade.

The honest summary. If you have obesity or type 2 diabetes, GLP-1 or GLP-1/GIP agonists are the most evidence-backed pharmacologic intervention available. They are not benign — GI side effects are common, rare pancreatitis and gallbladder issues happen, lean mass loss accompanies the weight loss unless you train and eat adequate protein — but for the populations studied, the benefit substantially outweighs the risk. Gray-market semaglutide (sold as "research peptide") exists and carries the usual sterility and dosing concerns. Compounded semaglutide from US compounding pharmacies occupies a middle ground discussed below.

Cognitive / neuroprotective (Selank, Semax, Cerebrolysin)

These are mostly Russian-developed peptides with much smaller evidence bases.

Selank is a synthetic heptapeptide derivative of tuftsin, developed in the USSR for anxiolytic use. Russian clinical trials report anxiolytic effects comparable to benzodiazepines without sedation or dependence. Western trials are essentially nonexistent. Nasal administration.

Semax is a synthetic analog of ACTH(4-10) with modifications for stability. Used in Russia for stroke recovery and cognitive enhancement. Some evidence for neuroprotective effects in stroke models. Western evidence is thin. Nasal administration.

Cerebrolysin is a mix of peptides and amino acids derived from pig brain, administered IV. Used in Europe and Russia for stroke recovery and dementia. Meta-analyses suggest modest benefit in acute stroke; evidence in dementia is mixed.

The honest summary. These are in a gray zone where Russian clinical experience and some published trials suggest real effects, but the methodological quality of much of the research is below Western standards, and double-blind placebo-controlled trials in Western populations are scarce. Biologically plausible, empirically undersettled. Not for casual self-experimentation.

Sexual / libido (PT-141 / Bremelanotide, Melanotan II)

PT-141 (Bremelanotide) is a melanocortin receptor agonist that acts centrally on MC4 receptors to produce sexual arousal. FDA-approved as Vyleesi for hypoactive sexual desire disorder in premenopausal women (2019). Subcutaneous injection; works within an hour. In trials, effect size for female HSDD was modest but real. Also used off-label in men for erectile dysfunction unresponsive to PDE5 inhibitors (Viagra, Cialis); some men report strong effects.

Side effects of PT-141 include nausea (quite common, can be severe), flushing, headache, and transient elevations in blood pressure. Not a benign drug.

Melanotan II is a melanocortin agonist developed for skin tanning and also produces sexual side effects. Sold extensively on the gray market for tanning. Produces darker skin pigmentation, often with uneven distribution, new moles, and occasional darkening of pre-existing moles. The dermatologic concerns about unregulated melanogenic stimulation are real — there are case reports of melanoma developing in users — though causation is hard to establish.

The honest summary. PT-141 has real effect and real side effects; it is FDA-approved for one indication and reasonably used off-label for specific populations with physician oversight. Melanotan II is being bought by people who want to tan without sun exposure and is probably one of the riskier gray-market peptides in terms of specific, known harms.

Immune / research (Thymosin Alpha-1)

Thymosin Alpha-1 is a 28-amino-acid peptide that modulates T-cell function. Approved in roughly 35 countries for chronic hepatitis B and C, used as an immunomodulator in some cancer and infection protocols. Not FDA-approved in the US. The evidence base is mixed — some trials show benefit in specific immune-compromised populations, the overall picture is of a real immunomodulator with narrow established indications.

In the peptide wellness market, it's often sold as a general immune booster. The evidence for that use is weak. The peptide has real immunological effects, but "real effects in immune-compromised patients" is not the same thing as "useful in healthy adults with a normal immune system."

What the evidence actually shows

The GLP-1 story (unusually strong data, real mechanism)

GLP-1 agonists are the exception, not the rule, in the peptide world. The evidence base is unusually strong because:

• The biology is well-understood. GLP-1 is a known gut hormone with a known receptor and known downstream effects on insulin secretion, gastric emptying, and hypothalamic appetite circuits.
• The clinical trials are large (STEP and SURMOUNT programs enrolled tens of thousands), randomized, and placebo-controlled.
• The endpoints are hard endpoints — weight, HbA1c, cardiovascular events — not surrogate markers or self-report.
• The effect sizes are large and consistent across trials.

Even so, not everything claimed for GLP-1s is proven. The "ozempic for addiction" and "ozempic for inflammation" headlines run ahead of the data. The weight-loss, glucose-lowering, and cardiovascular data are the established findings. Everything else is in active investigation.

BPC-157 (impressive rodent data, almost nothing human)

BPC-157 is the cleanest example of a peptide with a striking animal literature and almost no human data. The rodent studies are consistent: across tendon injuries, muscle damage, inflammatory bowel models, gastric ulcers, and blood vessel damage, BPC-157 produces acceleration of healing at doses that translate plausibly to human doses if you do the body weight math.

But rodent-to-human translation has a roughly 10% success rate in drug development. Many things that work beautifully in mice fail in people, often for reasons related to dosing, pharmacokinetics, or tissue-specific biology that differs across species. BPC-157 might be one of the 10% that translates. Or it might not. Until there is at least one well-designed human RCT, calling it "proven" or even "well-evidenced in humans" is not accurate.

The current market is filled with anecdote, underpowered open-label studies, and self-reported improvement from users who bought the peptide on the internet and wanted it to work. That is the weakest form of evidence.

The rest (case reports, underpowered trials, anecdote)

The honest description of most of the peptide wellness market: mechanistically plausible compounds with a thin evidence base consisting of animal studies, small early-phase trials, case reports, and user forum reports. The biology could be right. The clinical effect size could be real. It is also plausible that most of these compounds do nothing useful in humans at the doses being used, and we would not be able to tell from the existing data.

This is not a reason to dismiss everything. Early-stage drug development produces many compounds that eventually turn into real medicines. But the window between "biologically interesting" and "proven in humans" is where most of these compounds live, and treating them as proven because they are being sold and discussed online is a category error.

Legal and regulatory reality

FDA-approved vs. research chemicals

A small number of peptides are FDA-approved drugs with full regulatory status: semaglutide, tirzepatide, liraglutide, bremelanotide, tesamorelin, desmopressin, teriparatide, several insulin formulations, and others. These are prescription pharmaceuticals manufactured under GMP standards with verified purity and dose accuracy.

A much larger number of peptides are sold as "research chemicals" or "for research use only" by vendors who structure the sale legally while knowing the buyers are injecting them. BPC-157, TB-500, most GH secretagogues, CJC-1295, ipamorelin, melanotan, selank, semax, and many others fall in this category.

The "research use only" labeling is a legal fiction that reduces but does not eliminate the vendor's regulatory exposure. It is not a meaningful safety or quality guarantee. A research-grade peptide from a legitimate vendor can be pure and accurately dosed; it can also be underdosed, contaminated, or entirely inactive. Without independent testing, the buyer has no way to know.

The compounding pharmacy loophole (and why it's closing)

Compounding pharmacies are legally permitted to prepare medications that are not available as FDA-approved products, typically for individual patients. During the GLP-1 shortages of 2022-2024, a large compounding-pharmacy industry emerged selling "compounded semaglutide" and other peptides at lower prices than brand-name pharmaceuticals. Many cash-pay telehealth clinics use these compounded products.

The legal basis for this practice is narrower than it looks. Compounding is allowed when the active ingredient is on FDA's drug shortage list; as shortages resolve, the legal basis erodes. The FDA has been progressively tightening which peptides compounding pharmacies can prepare, and several peptides (BPC-157, melanotan II) have been explicitly placed on Category 2 of the FDA's compounding list, meaning compounding pharmacies should not prepare them.

The practical situation in 2026: compounded semaglutide and tirzepatide are still widely available but the legal ground under them is shifting; BPC-157 from US compounding pharmacies is largely gone; many clinics have moved to brand-name or gone international. This market is in active transition.

International mail and the customs question

A significant fraction of gray-market peptides enter the US through international mail from vendors in China, Eastern Europe, and elsewhere. Customs interdicts some shipments; most get through. The legal position of the buyer is typically not criminal prosecution for personal-use quantities of unscheduled compounds, but the shipments are subject to seizure, the vendors are sometimes frauds, and the products sometimes contain contaminants or substitutions.

Importing prescription drugs (including semaglutide and other FDA-approved peptides) without a valid prescription is explicitly illegal and more likely to be enforced. Importing unscheduled research chemicals exists in a legal gray zone where enforcement is inconsistent but not zero.

None of this is advice to break the law. It is a description of what the market actually looks like.

Buying peptides without getting scammed

Third-party testing (Janoshik, HPLC, mass spec)

If you are going to buy gray-market peptides, third-party testing is not optional. The minimum acceptable standard is a recent HPLC (high-performance liquid chromatography) and/or mass spectrometry report from an independent lab, dated within the last few months, matching the specific batch you are receiving.

Janoshik Analytics (based in the Czech Republic) has emerged as the most-used independent tester for the grey market. Their reports are published for batches submitted, and reputable vendors will link to their Janoshik results for each peptide.

Things to look for in a report:

• Peptide identity confirmed by mass spec (not just HPLC, which can match a similar-mass impurity).
• Purity ≥95% (ideally ≥98%). Lower purity raises the chance of bioactive contaminants.
• Date of testing within a reasonable window of when you're buying.
• Batch number matching your product.
• The same vendor name on the report as you are buying from. Some vendors use other vendors' certificates.

Vendors without current third-party testing should be treated as unknown products, regardless of their reputation.

What a legit vendor looks like

A reasonably-legitimate gray-market peptide vendor typically has:

• A consistent business for several years with stable website and communication
• Current third-party test reports linked per product and per batch
• Clear reconstitution and storage instructions
• Accurate dosing information (mg/vial, not vague "research quantity")
• A plausible shipping origin (vendors claiming both US-based fast shipping and rock-bottom pricing are usually one or the other but rarely both)
• Reasonable prices. A peptide that costs $200/vial at most established vendors and $25/vial somewhere else is almost always not what it claims to be.

What they do not have:

• Claims of specific medical benefits or treatment of diseases (regulatory bait)
• Testimonials with before/after photos (red flag; legitimate research-use vendors don't do this)
• Guarantees of specific effects
• Pressure sales tactics

Common lies and red flags

"Pharmaceutical grade" with no documentation. The phrase is meaningless without a COA.

"USP verified" or similar with no verification number. Same problem.

"Made in USA" from a vendor drop-shipping from China. Common, easy to verify by where the shipment originates.

In-house testing only. The vendor testing their own product is not independent testing.

Old COAs. A single 2022 test report being used for 2026 product is not meaningful.

Identical COAs across different batches. Indicates they are not actually retesting.

Stability claims beyond evidence. Peptides have real storage requirements. Claims that reconstituted BPC-157 is stable at room temperature for six months are either wrong or marketing.

Storage, reconstitution, sterility

Lyophilized (freeze-dried) peptide powder is reconstituted with bacteriostatic water (water containing 0.9% benzyl alcohol) for most peptides, or sterile saline for peptides that don't tolerate benzyl alcohol. Reconstitution concentrations depend on the peptide and target dose.

Storage. Lyophilized powder is stable at freezer temperature for many months to a few years. Reconstituted peptide should be refrigerated and used within weeks, not months. Some peptides degrade faster than others.

Sterility. Injecting non-sterile solution is a direct route to skin and soft tissue infection, and occasionally to systemic infection. Using sterile technique — new syringes, alcohol wipes, clean work surface, not touching the needle or the inside of vials — is not optional.

Dosing accuracy. Drawing 0.05 mL accurately from an insulin syringe is harder than it looks. Mistakes are usually in the direction of overdosing.

If any of this is intimidating, that is a reasonable signal that the self-administered peptide market is not safe for you. It is not safe for most people.

How to actually think about trying one

Start with why

Peptides are not a general-purpose optimization tool. Before considering any peptide intervention, the question to answer is: what specific problem am I trying to solve, and is this peptide the best-evidenced intervention for it?

If the problem is obesity: GLP-1 agonists are the most evidence-backed pharmacologic option, and the appropriate route is a legitimate prescription through a primary care doctor, obesity medicine specialist, or reputable telehealth clinic, not gray-market vendors.

If the problem is a slow-healing tendon injury: physical therapy, rest, progressive loading, and possibly PRP or corticosteroid injection have meaningfully more evidence than BPC-157.

If the problem is fatigue, low libido, or poor recovery: sleep, training load, testosterone if clinically indicated, and lifestyle factors are higher-leverage interventions than peptides.

If the problem is cognitive performance: sleep, exercise, caffeine, and stimulants in the ADHD context have more evidence than selank or semax.

For most problems most peptides are trying to solve, there is a more-evidenced first-line intervention. Peptides belong in the "considered after first-line options have been exhausted or don't apply" category, not the "try first because it's interesting" category.

The risk you're underpricing

The specific risks that peptide users tend to underprice:

Immunogenicity. Peptides can trigger antibody formation that neutralizes the drug, cross-reacts with endogenous proteins, or causes anaphylaxis. Rare but real, and more common with gray-market products that may have impurities promoting antibody formation.

Contaminants. Synthesis byproducts, residual solvents, bacterial endotoxins. These can cause fever, injection site reactions, or systemic effects. Third-party testing catches some of this; not all.

Infection. Injection without sterile technique is a known route to cellulitis, abscesses, and occasionally sepsis. Not common, but it happens.

Long-term unknowns. Most gray-market peptides have not been studied for chronic use. Effects on cancer risk, cardiovascular risk, and metabolic health over years are unknown. "I've used it for six months and I'm fine" is not long-term safety data.

Dependency effects. Some peptides suppress endogenous pathways. GH secretagogues can blunt natural GH pulsatility. HCG-like peptides affect the HPG axis. Reversibility is not guaranteed.

Legal risk. Low but nonzero for personal-use quantities of unscheduled compounds; higher for scheduled or prescription compounds.

One-at-a-time, journaling, reversibility

If you are going to try a peptide, the minimum good practice:

1. One at a time. Starting three peptides simultaneously makes it impossible to tell which is responsible for any effect or side effect.
2. Journal. Write down what you are taking, the dose, the timing, and what you notice. Subjective improvement in a peptide protocol is dominantly placebo unless tracked against specific measurable endpoints.
3. Time-limit the trial. If you don't see the effect you're looking for in 8-12 weeks, stop. Indefinite peptide use on the theory that "maybe it's doing something subtle" is how people end up on five compounds at once with no idea what any of them does.
4. Prefer reversible interventions. Peptides with short half-lives that can be stopped without withdrawal effects are safer to experiment with than ones with slow-onset dependency (GH secretagogues at high doses, certain hormonal peptides).
5. Have baseline labs. At minimum, CBC, comprehensive metabolic panel, lipid panel, HbA1c, and hormonal panel relevant to the peptide. Retest at 8-12 weeks. If the labs are moving in the wrong direction, stop.

None of this makes peptides safe. It makes the mistakes legible.

Honest take

Sources

• Lincoff A.M. et al., NEJM (2023) — Semaglutide and cardiovascular outcomes in obesity without diabetes (SELECT trial). Landmark evidence for cardiovascular benefit of GLP-1 agonism in non-diabetic obesity.
• Wilding J.P.H. et al., NEJM (2021) — Once-weekly semaglutide in adults with overweight or obesity (STEP 1). Primary efficacy data for semaglutide in obesity.
• Jastreboff A.M. et al., NEJM (2022) — Tirzepatide once weekly for the treatment of obesity (SURMOUNT-1). Primary efficacy data for tirzepatide.
• Sikiric P. et al., Current Pharmaceutical Design (2010) — Stable gastric pentadecapeptide BPC 157 and wound healing. Representative review of the BPC-157 rodent literature.
• Molinoff P.B. et al., Annals of the New York Academy of Sciences (2003) — PT-141: a melanocortin agonist for the treatment of sexual dysfunction. Original mechanism and early clinical work on bremelanotide.
• Kingwell B.A., Nature Reviews Drug Discovery (2015) — GLP-1 analogs for the treatment of type 2 diabetes mellitus: mechanism and review of the clinical data.
• Falutz J. et al., JAMA (2008) — Effects of tesamorelin on visceral fat in HIV-associated lipodystrophy. The primary clinical evidence for a GHRH analog.
• Nass R. et al., Annals of Internal Medicine (2008) — Effects of an oral ghrelin mimetic on body composition in older adults (MK-677 trial). One of the better-designed trials of a GH secretagogue.
• FDA Compounding Quality Act and ongoing Section 503A/503B guidance — Regulatory framework for compounded peptide products and current restrictions on specific compounds.
• Czaja A.J., World Journal of Hepatology (2017) — Thymosin alpha-1 in chronic liver disease. Representative clinical review of an immunomodulatory peptide with narrow established indications.