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Peptides Explained

Immune-modulating

Thymosin alpha-1

Approved in Italy and some non-EU countries, not in the Netherlands. A big sepsis trial found no benefit.

Authorised in some countries

Short page. This is a short page. A full page with the complete evidence review is planned for version 1.1. The grades and regulatory status below are complete and sourced.

At a glance

Is it an approved medicine?
In some countries Approved in Italy, India and Hong Kong for some uses. Not approved for the whole EU, or in the US.
Has it been tested in people?
Yes Large trials in many people, checked by regulators.
Is it allowed in sport?
Unclear Not named on the anti-doping list. Ask your anti-doping organisation before using it in sport. Regulatory status
What is the biggest risk?
Mostly mild. It changes the immune system. Online vials are not checked. More about the risks

Status checked on . The details and sources are further down this page.

Stop and get help if you notice

  • Swollen face or throat, or trouble breathing44,1
  • Hot, red, swollen or painful injection site42,20
  • High fever with chills, or feeling very ill43,42

If it is severe, call your local emergency number.

All warning signs, further down this page Warning signs for any peptide

The 30-second version

About 5 minutes for the short version; 11 with every detail open.

  • Thymosin alpha-1 is a natural peptide made of 28 amino acids. It was first found in the thymus.
  • Italy and some countries outside Europe use it as a medicine. The Netherlands does not.
  • In a large trial in sepsis it did not reduce deaths. Results in hepatitis B are mixed.
  • Side effects in trials were mostly mild, such as a sore injection site.
  • In 2024, US advisers said pharmacies should not make it. 17 voted no, 4 voted yes.
Class
Immune-modulating
Made of
28 amino acids; first found in calf thymus
Medicine name
Thymalfasin; sold in Italy as Zadaxin
Approved in
Italy, and some countries in Asia and elsewhere
Largest trial
1,106 adults with sepsis: no fewer deaths
Status in the EU
Not EU-wide, only nationally
Tested in people
Yes

Label facts, not dosing advice. Sources are in the sections below.

Last reviewed
Pink and purple stained tissue under a microscope: a large pink swirl of flattened cells surrounded by many small dark immune cells.
Tissue from the thymus, seen under a microscope. Thymosin alpha-1 was first found in calf thymus. Photo: Nephron (Wikimedia Commons) CC BY-SA 3.0 Image details

Each section starts with the short answer. The rest is folded under “In detail”.

Evidence profile

Four separate questions. Not a score.

Human clinical evidence How far has it been tested in people?
Authorised by a regulator
Preclinical volume How much laboratory and animal research exists?
Extensive
Source independence How many independent groups produced it?
Broadly replicated
Safety characterisation How well do we know the harms in humans?
Partial
In detail Why these grades: the reason for each step
Human clinical evidence
Authorised. Italy's medicines agency authorised it (as Zadaxin) to boost the response to flu vaccine in people with weak immune systems, and it is approved in some countries outside Europe, such as India for hepatitis B; its maker reports more approvals, which the FDA could not check. Large trials have been published, including a phase 3 trial in 1,106 people with sepsis. The grade describes the trial programme, not proof that it works: that sepsis trial and a blinded US hepatitis B trial found no clear benefit.
Preclinical volume
Extensive. On 22 October 2026 PubMed held 887 records on thymosin alpha-1; more than 250 of them are not reviews and are indexed under mice or rats.
Source independence
Broadly replicated. Many independent groups in the US, Italy and China have published on it; the original US group and two Italian groups appear on fewer than one in five records. Much of the clinical work had support from the manufacturer, and the key clinical claims have not held up consistently in the larger blinded trials.
Safety characterisation
Partial. Randomised trials, the largest with 1,106 people, found side effects similar to placebo over short courses, and the product has been sold for decades in some countries. Long-term safety data have not been published systematically, and the FDA judged the safety information inadequate for compounded products.

We never add these up. A compound can have a large animal literature from one laboratory and no human data at all — that is a specific situation, and a single number would hide it. How we grade evidence

In detail The molecule: amino-acid sequence and technical details
Amino-acid sequence28 amino acids

Ac-Ser-Asp-Ala-Ala-Val-Asp-Thr-Ser-Ser-Glu-Ile-Thr-Thr-Lys-Asp-Leu-Lys-Glu-Lys-Lys-Glu-Val-Val-Glu-Glu-Ala-Glu-Asn-OH

Read from the N-terminus (start) to the C-terminus (end).

Full name
Thymosin alpha 1
International non-proprietary name
thymalfasin
Also called
Thymalfasin, Tα1, Ta1
Authorised products
Zadaxin
Class
Immune-modulating
Body systems
Immune system
Formula
C129H215N33O55
Molecular mass
3,108.3 Da

What it actually is

What is thymosin alpha-1?

A natural immune peptide. It is a medicine in Italy and some other countries, not here.
Approved in some countries, but not in the Netherlands or the US. What is known about thymosin alpha-1, checked on 22 October 2026.
Thymosin alpha-1 (thymalfasin)
Made by the body?Yes First found in calf thymus in 1977. The medicine is a lab-made copy.1
Approved as a medicine anywhere?Yes In Italy, India and Hong Kong. Its maker reports more approvals in Asia, Latin America, Eastern Europe and the Middle East.2,1
Approved in the Netherlands or the US?No The CBG lists no product, and the FDA has approved none.3,4
The same as TB-500?No TB-500 comes from thymosin beta-4, a different protein.5

In the US, pharmacy-made versions are marketed as injections and nose sprays for many uses, from hepatitis to chronic fatigue.1 Those, and products sold online, are not the authorised medicine.

In detail The molecule, and where it is approved

Thymosin alpha-1 is a chain of 28 amino acids with an acetyl group at the start, formula C129H215N33O55, mass 3108.3 g/mol. Its official medicine name is thymalfasin.1,6

In Italy it is authorised to strengthen the response to flu vaccine in people with weak immune systems. In India it is approved for hepatitis B. Its maker reports approvals in other countries, mainly for hepatitis B and as an add-on to vaccines; the FDA could not check these itself.2,1 An Italian approval is a national authorisation: it does not apply in the Netherlands. The EU gave it orphan status for liver cancer in 2002, which is not an approval.2

Proposed mechanism

How does it work?

It switches on immune cells through germ sensors. Whether that helps patients is unclear.
The proposed causal chain, step by step

Each step is labelled with how well the link from the previous step is established.

  1. Step 1 Binding In cells

    Signals through toll-like receptors on immune cells

    In immune cells in the lab, thymosin alpha-1 worked through toll-like receptors, the sensors that spot germs. The FDA describes the same route.

  2. Step 2 Cell response In animals

    Dendritic cells mature and steer immune responses

    Dendritic cells matured and made IL-12, a signal that pushes T cells to fight infections. In mice after a bone-marrow transplant, it protected against a fungal lung infection.

  3. Step 3 Effect on the body In humans

    No fewer deaths in a large sepsis trial

    In 1,106 adults with sepsis, 28-day deaths were 23.4% with thymosin alpha-1 and 24.1% with placebo. Whether its immune effects help in other diseases remains uncertain.

In detail What each step rests on

The receptor and dendritic-cell findings come from Italian laboratories, in cells and mice.7 The FDA describes the same immune route, but notes that most animal studies used doses far above those used in people.1 The last step is a human result: no fewer deaths in sepsis.8

What the evidence actually shows

Does it work?

Not clear. The biggest trial found no gain. Hepatitis B results are mixed.

No fewer deaths in sepsis

23.4% vs 24.1%

died within 28 days, on the drug and on a dummy drug

Who took part TESTS: 1,106 adults with sepsis, 22 hospitals in China, double-blind phase 3 trial Source Wu et al. (2025)8 Evidence Human trials

A US trial with a dummy drug found no clear gain

14% vs 4%

cleared the virus with the drug and with placebo; this gap could be chance

Who took part Mutchnick 1999: 97 people with chronic hepatitis B, six months, US double-blind phase 3 trial Source Mutchnick et al. (1999)9 Evidence Human trials

An open Taiwanese trial without placebo did report more people clearing the virus.10 The FDA found the evidence for hepatitis B and its other reviewed uses insufficient.1

In detail Every study in one table

5 studies: 4 in humans, 1 in animals, 0 in cells, 0 reviews or other.

Studies discussed on this page
Study Species n Design Funding Research group What it found What it did not show
Chien et al. 1998 10 Humans 98 Randomised controlled trial (controlled) Not disclosed Independent group In 98 people with chronic hepatitis B in Taiwan, the virus cleared within 18 months in 41% after 26 weeks of treatment and 27% after 52 weeks, against 9% with no treatment. No placebo, so patients and doctors knew who was treated; small; the blinded US trial did not confirm it.
Mutchnick et al. 1999 9 Humans 97 Phase III trial (controlled, blinded) Not disclosed Independent group In 97 people with chronic hepatitis B, six months of injections cleared the virus in 14% against 4% on placebo, a difference that could be chance; the authors say this did not confirm earlier positive studies. Small; an outcome measure from before modern hepatitis B treatment; funding not stated in the abstract.
Romani et al. 2004 7 Mixed not reported Animal experiment (controlled) Not disclosed Independent group Thymosin alpha-1 made dendritic cells mature through toll-like receptors and protected transplanted mice from a fungal lung infection. Cells and mice; shows a possible route, not a benefit in people.
Gu et al. 2025 11 Humans 1,927 Meta-analysis Mixed Independent group Pooling 11 trials (1,927 patients), deaths at 28 days were lower overall, but not in the high-quality or multicentre trials. Written by the TESTS team; the benefit was not seen in the high-quality or multicentre trials; possible benefit in some groups, such as people with cancer, needs new trials; the authors say more patients are needed.
Wu et al. 2025 8 Humans 1,106 Phase III trial (controlled, blinded) Mixed Independent group In 1,106 adults with sepsis in 22 Chinese hospitals, injections every 12 hours for 7 days did not reduce 28-day deaths (23.4% against 24.1% with placebo); side effects were similar in both groups. One country; a 7-day course; partly funded by the manufacturer. Subgroup hints point both ways (possible benefit with diabetes, worse results under 60) and need their own trials.

A 2025 pooling of 11 sepsis trials found fewer deaths overall, but not in the high-quality or multicentre trials. Its authors see a possible benefit in some groups, such as people with cancer, and say more patients are needed.11 In the large sepsis trial itself, the hints in subgroups pointed both ways: possibly better with diabetes, possibly worse under the age of 60. Only new trials can settle this.8 Hundreds of laboratory papers come from many groups, and the original US group and two Italian groups appear on fewer than one in five.12 Many trials are still running, mostly in China and in cancer.13

Regulatory status

Is it legal?

Not approved here. US advisers said no to copies made by pharmacies.
It is not a medicine you can get from a Dutch pharmacy in the usual way. Status in the Netherlands and the US, and in sport, checked on 22 October 2026.
NetherlandsUnited States
Approved as a medicine?No The CBG lists no product. Italy’s approval does not apply here.3,2No Not FDA-approved.1
Legal to supply without approval?No Dutch law forbids supplying a medicine without a marketing authorisation, with narrow exceptions.14No Not on the pharmacy-compounding list. Advisers voted 17–4 against adding it.15
Allowed in sport?Unknown Not named on the list, and approved in some countries. Ask your anti-doping organisation.16Unknown The same worldwide rule.17
In detail Status in each country, and in sport
Regulatory status by jurisdiction
Jurisdiction Status Note Checked
European Union Authorised Authorised nationally in Italy (Zadaxin, as an add-on to flu vaccination in people with weak immune systems). No EU-wide authorisation, and none in the Netherlands. 2,1,18
Netherlands Not authorised Not authorised; supplying an unauthorised medicine is prohibited by the Geneesmiddelenwet. 3,14
United States Not authorised Not FDA-approved. In December 2024 FDA advisers voted 17–4 against adding it to the 503A compounding list. 1,15,20,4
Sport (WADA) Unclear (not named) Not named on the List, and approved in several countries, so S0 may not apply. No ruling found: ask your anti-doping organisation. 16,17,1

All statuses were checked on 22 October 2026. EMA’s medicines data hold no central authorisation.18 On 4 December 2024 the FDA’s Pharmacy Compounding Advisory Committee voted 4 for and 17 against adding thymosin alpha-1 to the 503A list, for both the free base and the acetate. Several members saw no convincing evidence of benefit and safety.15,19 The FDA lists it among substances once in category 2, for possible significant safety risks; the nomination was withdrawn.20

In sport, it is not named on the WADA list. Section S0 bans substances that no government health authority has approved, and thymosin alpha-1 is approved in several countries.16,17 We found no ruling from an anti-doping body. Do not mix it up with thymosin beta-4 (TB-500), which is banned.16

Risk profile

What are the risks?

In trials, side effects were mostly mild. It changes how the immune system works.
Trials found few side effects. Some groups need extra care. From the trials and the product labels quoted by the FDA, as of 22 October 2026.
Possible harmShown in people?
Pain or redness where it is injectedYes The most common side effect in trials.1
More side effects than placebo overallNo Not in the large sepsis trial.8
A flare of liver inflammation in hepatitis BYes A label warns of short rises in a liver enzyme.1
Problems in autoimmune disease or after a transplantUnknown Labels advise caution, because it boosts the immune system.1
An immune reaction to a pharmacy-made or online productUnknown The FDA names this risk.20
In detail What the labels say, and why

The FDA quotes two foreign labels. The Italian label says not to use it in children, to take care in people with allergies, and to judge autoimmune disease case by case.1 The Indonesian label warns of short liver-enzyme flares in hepatitis B. It says not to use it in people whose immune system is deliberately suppressed, such as after a transplant, unless the benefit clearly outweighs the risk.1 The reason is the same in each case: a drug that turns the immune system up can work against treatments that turn it down.

In the 1,106-person sepsis trial, serious adverse events occurred in 26.8% on the drug and 29.3% on placebo.8 Those numbers reflect how ill people with sepsis are, not harm from the drug.

If someone is going to do this anyway

This section exists to reduce harm. It gives no doses, schedules or sourcing advice, and it is not a recommendation to use this compound.

How can someone lower the risk?

Check the product first, involve a doctor, and know when to stop.

If your product did not come from a pharmacy: check before you use it

These checks can show that something is wrong. None of them can show that a product is good or free of germs.21,22,23

Tick each box when you have checked it.

  • The seal and the vial are whole

    A broken cap or seal, or a cracked vial, can let germs in. Then do not use it.24,25,26

  • The label shows the name, amount, batch number and expiry date

    In the EU, a medicine must show all four, even on a small vial. If one is missing, or the date has passed, that is a warning sign. Take a photo of the label.27,24

  • For Thymosin alpha-1

    Check the name on the label. Alpha-1 and beta-4 are not the same thing.1,5

  • It looks right

    A liquid, or a powder after mixing, should be clear and colourless, with no bits. Is it cloudy, has it changed colour, or do you see bits? Then do not use it.28,29

  • A lab report proves little if:

    • its batch number is not the one on your vial;
    • it does not name the lab, or has no date or signature;
    • it shows only purity (HPLC), with no test of what it is, such as mass spectrometry;
    • it has no test for germs (sterility) or for toxins from germs (endotoxin).

    Even a full report covers only one sample. A report from the seller comes from someone who gains if it looks good. It cannot show that your vial is clean.30,31,32,5,33

    What a certificate of analysis shows, and what it does not

  • It was kept as the label says

    Heat, freezing and sunlight can damage a peptide. Did it arrive warm, or was it frozen? Then do not use it. Often nobody can tell you how it was kept on the way. If you cannot know, you cannot rule out damage. When in doubt, throw it out.29,34,35,26

    When to throw a vial away

  • Clean steps, and a new sterile needle and syringe every time

    Wash your hands and wipe the rubber top with alcohol. Never share a needle, a syringe or a vial.26,36,34

    Sterile technique, step by step

  • Keep the vial, its label and any papers

    Keep them, even when the vial is empty, until you know you feel well. If you need a doctor, bring them. A lab can test what was inside.37,38

    If something goes wrong

  • Tell a doctor, and agree which checks fit you

    A doctor can help you choose blood tests that fit what you use. In the Netherlands, your doctor must keep what you say private.39,40,41

    Which checks matter, and whyTalking to your doctor

  • Know the warning signs before you start

    Spreading redness, fever, a swollen face or hard breathing need help fast. If it is severe, call your local emergency number.42,43,44

    All warning signs, and how fast to act

When to stop and get help

Sources 44, 42, 43

Stop-now warning signs

Call your local emergency number now

  • Confusion or slurred speech, very fast breathing, or pale, blue or blotchy skin, often with fever or shivering These can be signs of sepsis: the body's reaction to an infection has started to damage its own organs.
  • Fainting and not waking up within a minute, or fainting with chest pain, a racing heart or a fit This can be a dangerous heart rhythm or a severe allergic reaction.
  • Pain at the injection spot that is much worse than it looks, or dark, purple or grey patches or blisters there This can be a rare, fast-spreading infection of the deep layers under the skin (necrotising fasciitis).
  • Swelling of the lips, tongue or throat, trouble breathing or swallowing, wheezing, a hoarse voice, or feeling faint, soon after an injection This can be a severe allergic reaction (anaphylaxis), which is life-threatening and gets worse very quickly.

Get medical help today

  • Fever, shivering or feeling very ill in the days after an injection Germs from the needle, the skin or the product may have reached your blood. If you also have a fast heartbeat or fast breathing, call your local emergency number.
  • Redness, heat, swelling or pain around the injection spot that keeps growing or getting worse This can be a skin infection (cellulitis), which needs antibiotics before it spreads.
  • Red lines that run from the injection spot towards the armpit or groin The infection may be spreading along the lymph vessels, and from there into the blood. If you also have a fever with a fast heartbeat or fast breathing, call your local emergency number.
  • A painful, warm lump that fills with pus This is probably an abscess: it often needs draining by a doctor, so do not squeeze it.
  • You were pricked by a needle that someone else had used Blood on a used needle can pass on HIV and hepatitis B or C, and preventive treatment works best within hours.

Stop and contact a doctor

  • You fainted, but woke up quickly and now feel well Fainting is often harmless, but a doctor should check the cause.
  • A new mole, or a mole that changes size, shape or colour, itches or bleeds A changing mole can be skin cancer, and tanning peptides such as melanotan II have been linked to new and changing moles in case reports.
  • A lump at an injection spot that does not go away, or keeps growing A doctor should check whether it is an abscess, a reaction to the product or something else.
  • An itchy, raised rash, or puffy eyes or lips, while breathing stays normal Your body may be reacting to the product, and using it again can bring the reaction back.
In detail The legal route, checks, and who should not use it

In the Netherlands, a medicine authorised abroad can in rare cases be supplied for one named patient. The doctor signs a statement that no Dutch medicine fits. A pharmacy then asks the inspectorate, which decides.45 See legal routes and talking to your doctor.

  • Liver tests, if you have hepatitis B, because of the liver-enzyme flares on the label.1
  • Medicines that damp down the immune system. You may take these after a transplant or for an autoimmune disease. If so, talk to your specialist first. The labels warn about this mix.1
  • Children, pregnancy and breastfeeding: the labels advise against use in children and in pregnancy or breastfeeding.1

See product risk and sterile technique.

Sources

Every claim on this page links to one of these sources. Scholarly sources link to their DOI; regulatory sources to the regulator's own page.

In detail All 45 sources, numbered as in the text
  1. U.S. Food and Drug Administration (2024). FDA Briefing Document for Thymosin Alpha-1 Related Bulk Drug Substances (Thymosin alpha-1 (free base) and Thymosin alpha-1 acetate), Pharmacy Compounding Advisory Committee meeting, 4 December 2024. Regulator fda.gov — accessed 22 October 2026 ↩
  2. European Medicines Agency (2003). EU/3/02/110 – orphan designation for treatment of hepatocellular carcinoma (thymalfasin). Regulator ema.europa.eu — accessed 22 October 2026 ↩
  3. College ter Beoordeling van Geneesmiddelen (CBG-MEB) (2026). Geneesmiddeleninformatiebank (database of medicines authorised in the Netherlands). Regulator geneesmiddeleninformatiebank.nl — accessed 20 October 2026 ↩
  4. U.S. Food and Drug Administration (2026). openFDA Drugs@FDA queries, 22 October 2026: selank, semax, epitalon, MOTS-c, thymalfasin, thymosin. openFDA. Dataset api.fda.gov — accessed 22 October 2026 ↩
  5. U.S. Food and Drug Administration (2026). FDA Briefing Document for TB-500-Related Bulk Drug Substances (TB-500 (free base) and TB-500 acetate), Pharmacy Compounding Advisory Committee meeting, 23–24 July 2026. Regulator fda.gov — accessed 20 October 2026 ↩
  6. National Center for Biotechnology Information (2026). PubChem Compound Summary for CID 16130571, Thymalfasin. PubChem. Dataset pubchem.ncbi.nlm.nih.gov — accessed 22 October 2026 ↩
  7. Romani L, Bistoni F, Gaziano R, Bozza S, Montagnoli C, Perruccio K, Pitzurra L, Bellocchio S, Velardi A, Rasi G, Di Francesco P, Garaci E (2004). Thymosin alpha 1 activates dendritic cells for antifungal Th1 resistance through toll-like receptor signaling. Blood 103:4232-4239. Research article doi:10.1182/blood-2003-11-4036 ↩
  8. Wu J, Pei F, Zhou L, Li W, Sun R, Li Y, Wang Z, He Z, Zhang X, Jin X, et al. (2025). The efficacy and safety of thymosin α1 for sepsis (TESTS): multicentre, double blinded, randomised, placebo controlled, phase 3 trial. BMJ 388:e082583. Clinical trial doi:10.1136/bmj-2024-082583 ↩
  9. Mutchnick MG, Lindsay KL, Schiff ER, Cummings GD, Appelman HD, Peleman RR, Silva M, Roach KC, Simmons F, Milstein S, Gordon SC, Ehrinpreis MN (1999). Thymosin alpha1 treatment of chronic hepatitis B: results of a phase III multicentre, randomized, double-blind and placebo-controlled study. Journal of Viral Hepatitis 6:397-403. Clinical trial doi:10.1046/j.1365-2893.1999.00181.x ↩
  10. Chien RN, Liaw YF, Chen TC, Yeh CT, Sheen IS (1998). Efficacy of thymosin alpha1 in patients with chronic hepatitis B: a randomized, controlled trial. Hepatology 27:1383-1387. Clinical trial doi:10.1002/hep.510270527 ↩
  11. Gu B, Zhou Y, Nie Y, Wang L, Liang L, Liao Z, Wen J, Guan X, Chen M, Wu J, Pei F (2025). Efficacy of thymosin α1 for sepsis: a systematic review and meta-analysis of randomized controlled trials. Frontiers in Cellular and Infection Microbiology 15:1673959. Meta-analysis doi:10.3389/fcimb.2025.1673959 ↩
  12. National Library of Medicine (2026). PubMed searches for thymosin alpha 1 (thymalfasin), 22 October 2026 (record counts). PubMed. Dataset pubmed.ncbi.nlm.nih.gov — accessed 23 October 2026 ↩
  13. ClinicalTrials.gov (2026). ClinicalTrials.gov search, 22 October 2026: thymalfasin or thymosin alpha 1, recruiting, not yet recruiting or active. Dataset clinicaltrials.gov — accessed 22 October 2026 ↩
  14. Staten-Generaal / Koninkrijk der Nederlanden (2007). Geneesmiddelenwet (BWBR0021505). wetten.overheid.nl. Law wetten.overheid.nl — accessed 20 October 2026 ↩
  15. U.S. Food and Drug Administration (2025). Final Summary Minutes of the Pharmacy Compounding Advisory Committee Meeting, December 4, 2024. Regulator fda.gov — accessed 22 October 2026 ↩
  16. World Anti-Doping Agency (2025). World Anti-Doping Code International Standard: Prohibited List 2026. Regulator wada-ama.org — accessed 20 October 2026 ↩
  17. World Anti-Doping Agency (2026). World Anti-Doping Code International Standard: Prohibited List 2027 (in effect 1 January 2027). Regulator wada-ama.org — accessed 20 October 2026 ↩
  18. European Medicines Agency (2026). Medicines data download (JSON report of all EPARs: authorised, refused, withdrawn and suspended medicines). Dataset ema.europa.eu — accessed 20 October 2026 ↩
  19. U.S. Food and Drug Administration (2025). December 4, 2024: Meeting of the Pharmacy Compounding Advisory Committee (updated meeting time and public participation information). Regulator fda.gov — accessed 22 October 2026 ↩
  20. U.S. Food and Drug Administration (2026). Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. Regulator fda.gov — accessed 20 October 2026 ↩
  21. Inspectie Gezondheidszorg en Jeugd (IGJ) (2026). Online medicijnen. Regulator igj.nl — accessed 22 October 2026 ↩
  22. Ashraf AR, Mackey TK, Vida RG, Kulcsár G, Schmidt J, Balázs O, Domián BM, Li J, Csákó I, Fittler A (2024). Multifactor Quality and Safety Analysis of Semaglutide Products Sold by Online Sellers Without a Prescription: Market Surveillance, Content Analysis, and Product Purchase Evaluation Study. Journal of Medical Internet Research 26:e65440. Research article doi:10.2196/65440 ↩
  23. Smith RM, Schaefer MK, Kainer MA, Wise M, Finks J, et al. (2013). Fungal infections associated with contaminated methylprednisolone injections. The New England Journal of Medicine 369:1598-1609. Research article doi:10.1056/NEJMoa1213978 ↩
  24. U.S. Food and Drug Administration (2020). BeSafeRx: Considering an Online Pharmacy?. Regulator fda.gov — accessed 22 October 2026 ↩
  25. Hospira, Inc. / DailyMed (National Library of Medicine) (2026). Sterile Water for Injection, USP: prescribing information. Official product information dailymed.nlm.nih.gov — accessed 20 October 2026 ↩
  26. World Health Organization (2010). WHO best practices for injections and related procedures toolkit (WHO/EHT/10.02). World Health Organization, Geneva. Report who.int — accessed 20 October 2026 ↩
  27. European Parliament and Council of the European Union (2001). Directive 2001/83/EC on the Community code relating to medicinal products for human use (consolidated text). Official Journal of the European Communities, L 311. Law eur-lex.europa.eu — accessed 20 October 2026 ↩
  28. U.S. Food and Drug Administration / DailyMed (National Library of Medicine) (2026). EGRIFTA SV (tesamorelin for injection): prescribing information and instructions for use. Official product information dailymed.nlm.nih.gov — accessed 20 October 2026 ↩
  29. European Medicines Agency (2026). Wegovy (semaglutide): EPAR — overview and product information. Official product information ema.europa.eu — accessed 20 October 2026 ↩
  30. European Medicines Agency (ICH) (2000). ICH Q7 Good manufacturing practice for active pharmaceutical ingredients (CPMP/ICH/4106/00). European Medicines Agency, scientific guideline. Regulator ema.europa.eu — accessed 22 October 2026 ↩
  31. European Medicines Agency, CHMP and CVMP (2025). Guideline on the Development and Manufacture of Synthetic Peptides (EMA/CHMP/CVMP/QWP/367182/2025). European Medicines Agency. Regulator ema.europa.eu — accessed 22 October 2026 ↩
  32. U.S. Food and Drug Administration (2026). FDA Briefing Document for BPC-157-Related Bulk Drug Substances (BPC-157 (free base) and BPC-157 acetate), Pharmacy Compounding Advisory Committee meeting, 23–24 July 2026. Regulator fda.gov — accessed 20 October 2026 ↩
  33. Janvier S, Cheyns K, Canfyn M, Goscinny S, De Spiegeleer B, Vanhee C, Deconinck E (2018). Impurity profiling of the most frequently encountered falsified polypeptide drugs on the Belgian market. Talanta 188:795-807. Research article doi:10.1016/j.talanta.2018.06.023 ↩
  34. U.S. Food and Drug Administration (2026). FDA's concerns with unapproved GLP-1 drugs used for weight loss. Regulator fda.gov — accessed 20 October 2026 ↩
  35. Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS (2010). Stability of protein pharmaceuticals: an update. Pharmaceutical Research 27:544-575. Review doi:10.1007/s11095-009-0045-6 ↩
  36. Centers for Disease Control and Prevention (2024). Preventing Unsafe Injection Practices. Regulator cdc.gov — accessed 20 October 2026 ↩
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