The ALTA Journal
Laboratory handling guides, how to read the testing, where the law sits, and plain summaries of what the published research on each compound actually reports. No dosing, no protocols, no claims.
Apitegromab explained: the first approved muscle-protecting antibody, and what it means for weight loss
Apitegromab is Scholar Rock's antibody that stops the body's main muscle brake, myostatin, from switching on. It became the first drug of its kind ever approved, for the muscle-wasting disease SMA in the US in September 2026. In obesity it doesn't add weight loss: with tirzepatide, it made more of the weight lost come from fat and less from muscle. What it is, what the trials show, and whether you can get it.
Read → 9 October 2026 · 9 min readApitegromab and bodybuilding: can a myostatin blocker really build muscle?
Myostatin is the body's brake on muscle, and animals born without it are famously huge. That is why bodybuilders are curious about apitegromab, the first approved drug that blocks it. But in people, myostatin blockers have added only modest muscle, rarely more strength, and none has ever been tested in healthy or trained adults. What the evidence really shows, the risks, and why it is banned in sport.
Read → 9 October 2026 · 10 min readWhat is retatrutide? The triple-hormone peptide, explained simply
Retatrutide, often shortened to reta, is Eli Lilly's experimental once-weekly peptide that acts on three appetite and metabolism hormones at once: GLP-1, GIP and glucagon. In its largest phase 3 trial, people on the highest amount lost 28.3% of their body weight on average over 80 weeks. What it is, how it works, the results, the side effects and where it stands.
Read → 6 October 2026 · 7 min readWhat is PT-141? Bremelanotide, the brain-acting peptide behind Vyleesi, and what the trials show
PT-141, or bremelanotide, is a seven-amino-acid ring-shaped peptide that acts on melanocortin receptors in the brain rather than on blood flow. It was approved in the US in 2019 as Vyleesi for low sexual desire in premenopausal women, after two trials found small but real improvements; nausea was common. It is not licensed in the UK. What it is, what the trials found and where it stands.
Read → 6 October 2026 · 7 min readWhat is tesamorelin? The growth hormone-releasing peptide, its trials on belly and liver fat, and where it stands
Tesamorelin is a lab-made copy of growth hormone-releasing hormone, the brain signal that tells the pituitary to release growth hormone. In large trials in people with HIV it cut deep abdominal fat by about 15% in six months, and later liver fat, but the fat returned when it was stopped. It is approved in the US as Egrifta, not in the UK, and is banned in sport. What it is and what the trials show.
Read → 2 October 2026 · 7 min readWhat is MOTS-c? The peptide made by your mitochondria, and what the research shows
MOTS-c is a 16-amino-acid peptide made from a gene inside mitochondria, the cell's power plants. In mice it helps muscle use glucose, protects against diet-induced weight gain and improves physical performance in old age; in people, exercise raises it. The only human trial was of a different analogue, and it was dropped. What it is, what the research shows and where it stands.
Read → 2 October 2026 · 6 min readWhat is epitalon? The four-amino-acid ageing peptide and what the evidence really shows
Epitalon (epithalon) is a four-amino-acid peptide, Ala-Glu-Asp-Gly, designed in St Petersburg from a cow pineal-gland extract. It switched on telomerase and lengthened telomeres in human cells, and modestly extended the lives of the longest-lived mice. Almost all of that work comes from one group; a 2025 UK study has now repeated the telomere finding in cells. What it is, what the evidence shows and its limits.
Read → 29 September 2026 · 13 min readMyostatin inhibitors explained: the pathway, the antibodies and why muscle matters in GLP-1 weight loss
A myostatin inhibitor is anything that blocks the signal telling muscle to stay small. Four monoclonal antibodies are now in trials alongside GLP-1 drugs to stop the muscle loss that comes with rapid weight loss. What the pathway is, what each antibody does, what came before, and why none of them is available outside a clinical trial.
Read → 29 September 2026 · 12 min readTrevogrumab and garetosmab: the COURAGE results, side effects, and when they could be available
Trevogrumab (REGN1033) is Regeneron's fully human antibody against myostatin (GDF8). In the phase 2 COURAGE trial it prevented about half of the lean mass lost on semaglutide, and with garetosmab added it prevented more, at the cost of far more discontinuations and two deaths in the triplet arm. The figures, the safety record and where it stands.
Read → 29 September 2026 · 8 min readGaretosmab: Regeneron's anti-activin A antibody, from FOP to the obesity triplet
Garetosmab is Regeneron's antibody against activin A, approved by the FDA in August 2026 for adults with fibrodysplasia ossificans progressiva after the phase 3 OPTIMA trial cut new bone lesions by 90% or more. It is also the third component of the COURAGE obesity triplet, where it improved body composition but was linked to high discontinuation and two deaths. What the trials report.
Read → 29 September 2026 · 17 min readBimagrumab: what it is, the BELIEVE results, side effects, price and when it could reach the UK
Bimagrumab is a monoclonal antibody that blocks the activin type II receptors, owned by Eli Lilly since its 2023 purchase of Versanis. In the phase 2b BELIEVE trial with semaglutide it produced 22.1% weight loss at 72 weeks with 92.8% of it from fat, and on its own it lost fat while adding lean mass. Its history at Novartis, the tirzepatide trials, and a plain statement for anyone searching 'bimagrumab buy'.
Read → 29 September 2026 · 9 min readMuscle loss on GLP-1 peptides: what the DXA substudies say for semaglutide, tirzepatide and retatrutide
In the DXA substudies of their own trials, semaglutide lost 9.7% of lean body mass alongside 19.3% of fat, tirzepatide lost 10.9% of lean mass alongside 33.9% of fat, and retatrutide's lean share was reported as consistent with other treatments. Across trials, a quarter to a third of the weight lost on these drugs is lean tissue. The figures per drug, what lean mass is and is not, and the antibody trials built to change the ratio.
Read → 19 September 2026 · 8 min readRetatrutide pen vs vial: what UK vendors actually sell
A pre-filled retatrutide pen and a lyophilised retatrutide vial are different products in handling, stability, traceability and price per milligram, and who filled the pen matters more than the format. What each one is and how the two we supply compare.
Read → 19 September 2026 · 9 min readHow to get retatrutide in the UK: what is legal, the trial results, the release date and how to check a vendor
Retatrutide is an unlicensed investigational compound sold in the UK as a research reagent. Where that leaves a buyer legally, what separates a credible vendor from a risky one, and what the market charges.
Read → 19 September 2026 · 8 min readNAD+ injections in the UK: pens, vials and what is in them
NAD+ is a coenzyme, not a peptide, and the UK market sells it as pre-filled pens, lyophilised vials and clinic infusions. What each format contains, how NAD+ relates to NMN and NR, and where the law sits.
Read → 19 September 2026 · 8 min readAre peptides steroids? Peptides vs steroids vs SARMs explained
Peptides, anabolic steroids and SARMs are three unrelated classes of molecule that get lumped together online. The chemistry, the UK legal status of each, and the WADA position, side by side.
Read → 19 September 2026 · 8 min readWhat is KPV? The anti-inflammatory tripeptide from alpha-MSH
KPV is the three-residue C-terminal fragment of the pigmentation hormone alpha-MSH, studied since the 1990s for anti-inflammatory activity that does not depend on melanocortin receptors. What the research reports and where it fits in the KLOW blend.
Read → 19 September 2026 · 8 min readBPC-157 oral vs injectable: why it survives the stomach and what that means
BPC-157 is unusual among peptides in surviving gastric acid, which is why the research includes oral as well as injectable studies and why capsules and sprays are on the market. What each route's studies report and what a lyophilised vial is for.
Read → 19 September 2026 · 7 min readDoes filtering peptides remove bacteria? Sterile filtration explained
Passing a peptide solution through a 0.22 micron syringe filter removes bacteria and fungi; it does not remove viruses, endotoxin or chemical contaminants, and it can remove some of the peptide. What sterile filtration is for and where it fits with bacteriostatic water and lot testing.
Read → 19 September 2026 · 8 min readThe Wolverine stack explained: BPC-157 vs TB-500, and why the two are paired
The Wolverine stack is a forum name for BPC-157 and TB-500 supplied together. What each peptide is, why the tissue-repair research pairs them, what a blend vial is versus two vials, and what it costs.
Read → 19 September 2026 · 9 min readPeptides studied for skin and hair: a research round-up
A tour of the peptides that appear in skin and hair research, from GHK-Cu and the cosmetic signal peptides to the neurotransmitter-inhibiting and carrier types, what each body of work measured, and where research-grade reagents fit.
Read → 19 September 2026 · 8 min readPeptides studied for sleep: DSIP, epitalon and what the research measured
Sleep is regulated by peptides, from orexin to the pineal system, and two research peptides sit in that literature: DSIP, named for the slow-wave sleep it produced in rabbits in 1977, and epitalon, studied for melatonin rhythm. What the research measured and where it stands.
Read → 18 September 2026 · 8 min readWhat are peptides? Amino acid chains, proteins, hormones and synthesis
The chemistry behind the word: what a peptide chain is, where the line with proteins sits, what peptide hormones do, and how a synthetic peptide is built one residue at a time.
Read → 18 September 2026 · 6 min readBacteriostatic water explained: what it is, how it differs from sterile water, and where to get it in the UK
The diluent every peptide laboratory keeps on the shelf: what the benzyl alcohol does, why the 28-day rule exists, when plain sterile water is the better choice, and what to look for when buying it in the UK.
Read → 18 September 2026 · 6 min readWhat is DSIP? The delta sleep-inducing peptide, its origin and what the research shows
A nine-residue peptide found in the blood of sleeping rabbits nearly fifty years ago, with a name that promises more than the evidence has delivered, and a genuinely unresolved question about where it comes from.
Read → 18 September 2026 · 6 min readGLOW vs KLOW peptide blends: what is in each, what KPV is, and which we sell
GLOW is GHK-Cu, BPC-157 and TB-500 together; KLOW is the same three plus KPV. What each component is, what the research on each covers, and why the blend format has trade-offs.
Read → 18 September 2026 · 7 min readHow to buy research peptides in the UK: the supplier checklist
Ten things to check before ordering from any UK peptide supplier, from lot-matched certificates to where the stock physically sits, and the questions a good supplier will refuse to answer.
Read → 18 September 2026 · 5 min readInsulin syringes explained: sizes, gauges, the U-100 scale and laboratory use
Why a 1 mL insulin syringe is the standard tool for measuring small volumes of diluent, what the numbers on the packet mean, and how to handle and dispose of them.
Read → 18 September 2026 · 8 min readGLP-1 receptor agonists explained: incretins, the peptides from exenatide to retatrutide, and where each stands
The incretin story from a lizard's saliva to a triple agonist: what GLP-1 and GIP do, how the peptides were engineered to last a week, and which are licensed medicines versus research compounds.
Read → 17 September 2026 · 7 min readHow to reconstitute peptides: a laboratory guide
Which diluent to use, how to work out the volume for a target concentration, and the handling steps that keep a lyophilised peptide intact.
Read → 17 September 2026 · 8 min readHow to store peptides, and how long lyophilised peptides last at room temperature
Temperatures, light, moisture, freeze-thaw cycles and aliquoting: what actually determines how long a peptide stays within specification.
Read → 17 September 2026 · 7 min readHow to read a peptide certificate of analysis
HPLC purity, mass spec identity, net peptide content and endotoxin: what each line on a COA means and which ones sellers tend to leave out.
Read → 17 September 2026 · 8 min readAre peptides legal in the UK? Research peptides and the law explained
Which laws actually apply to research peptides in the UK, what a supplier can and cannot do, and why research use only is a legal condition rather than a slogan.
Read → 17 September 2026 · 7 min readWhat is BPC-157? Origin, sequence and what the research covers
Where the Body Protection Compound came from, why it is unusually stable, and what more than three decades of animal studies have and have not shown.
Read → 17 September 2026 · 6 min readWhat is TB-500? Thymosin beta-4, the full protein and the fragment, and the research behind them
The 43-residue protein thymosin beta-4 and the seven-residue fragment, both sold as TB-500, which one we supply, and what the cell migration research actually measured.
Read → 17 September 2026 · 7 min readGHK-Cu copper peptide: what it is, why it is blue, topical vs injectable, and what the research says
A three-residue peptide that binds copper, turns blue, declines with age and has one of the broadest gene-expression footprints of any small molecule studied.
Read → 17 September 2026 · 7 min readRetatrutide vs tirzepatide vs semaglutide: receptors, licences and trial results
One licensed GLP-1 agonist, one licensed dual agonist, one unlicensed triple agonist: how the three differ on the published record.
Read → 17 September 2026 · 6 min readSemax vs Selank: what each peptide is and how the research differs
An ACTH fragment analogue and a tuftsin analogue, both from the same Moscow institute, with different proposed mechanisms and a shared evidence gap outside Russia.
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