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Semax Research Peptides

Compare Semax research products by labelled quantity, price per mg, testing evidence and product transparency. See what’s available from suppliers and use our comparison tools to make more informed decisions.

Research-use products only. Not presented as supplements, medicines, or products for human or veterinary consumption.
6products compared
3labelled quantities
£1.50 – £3.50per mg
3with verified testing evidence

Top Picks

Best Overall

Semax 10mgPepSource

Why this score?
Testing & analytical evidence
40/45
Value
13/25
Product identity
14/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Quantity
10 mg / vial
Testing evidence
Evidence status
Verified independent evidence
Manufacturer statement
"Every batch is independently third-party tested for HPLC purity and mass-spectrometry identity, and the certificate of analysis for the batch you receive is published on our lab results page." "Purity: Verified by HPLC on every batch — the measured figure for your lot is published on its certificate of analysis"
Laboratory
Freedom Diagnostics Testing
Certification body
Not recorded
Batch
XA10-2606-02-IV
Batch-specific report
Recorded
Report date
2026-06-02
Evidence checked
2026-09-22
£3.50per mg
£35.00per pack
View AnalysisBuy Now
Product & testing details
Supplier
PepSource
Vials per pack
1
Price per vial
£35.00
Listing last checked
2026-09-22 11:04:33
Evidence status
Verified independent evidence
Manufacturer statement
"Every batch is independently third-party tested for HPLC purity and mass-spectrometry identity, and the certificate of analysis for the batch you receive is published on our lab results page." "Purity: Verified by HPLC on every batch — the measured figure for your lot is published on its certificate of analysis"
Laboratory
Freedom Diagnostics Testing
Certification body
Not recorded
Batch
XA10-2606-02-IV
Batch-specific report
Recorded
Report date
2026-06-02
Evidence checked
2026-09-22

Semax 10mg

PepSource
Why this score?
Testing & analytical evidence
40/45
Value
13/25
Product identity
14/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Testing evidence
Evidence status
Verified independent evidence
Manufacturer statement
"Every batch is independently third-party tested for HPLC purity and mass-spectrometry identity, and the certificate of analysis for the batch you receive is published on our lab results page." "Purity: Verified by HPLC on every batch — the measured figure for your lot is published on its certificate of analysis"
Laboratory
Freedom Diagnostics Testing
Certification body
Not recorded
Batch
XA10-2606-02-IV
Batch-specific report
Recorded
Report date
2026-06-02
Evidence checked
2026-09-22
£3.50per mg
£35.00per pack
View AnalysisBuy Now

Best Tested

Semax 10mgPepSource

Why this score?
Testing & analytical evidence
40/45
Value
13/25
Product identity
14/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Quantity
10 mg / vial
Testing evidence
Evidence status
Verified independent evidence
Manufacturer statement
"Every batch is independently third-party tested for HPLC purity and mass-spectrometry identity, and the certificate of analysis for the batch you receive is published on our lab results page." "Purity: Verified by HPLC on every batch — the measured figure for your lot is published on its certificate of analysis"
Laboratory
Freedom Diagnostics Testing
Certification body
Not recorded
Batch
XA10-2606-02-IV
Batch-specific report
Recorded
Report date
2026-06-02
Evidence checked
2026-09-22
£3.50per mg
£35.00per pack
View AnalysisBuy Now
Product & testing details
Supplier
PepSource
Vials per pack
1
Price per vial
£35.00
Listing last checked
2026-09-22 11:04:33
Evidence status
Verified independent evidence
Manufacturer statement
"Every batch is independently third-party tested for HPLC purity and mass-spectrometry identity, and the certificate of analysis for the batch you receive is published on our lab results page." "Purity: Verified by HPLC on every batch — the measured figure for your lot is published on its certificate of analysis"
Laboratory
Freedom Diagnostics Testing
Certification body
Not recorded
Batch
XA10-2606-02-IV
Batch-specific report
Recorded
Report date
2026-06-02
Evidence checked
2026-09-22

Semax 10mg

PepSource
Why this score?
Testing & analytical evidence
40/45
Value
13/25
Product identity
14/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Testing evidence
Evidence status
Verified independent evidence
Manufacturer statement
"Every batch is independently third-party tested for HPLC purity and mass-spectrometry identity, and the certificate of analysis for the batch you receive is published on our lab results page." "Purity: Verified by HPLC on every batch — the measured figure for your lot is published on its certificate of analysis"
Laboratory
Freedom Diagnostics Testing
Certification body
Not recorded
Batch
XA10-2606-02-IV
Batch-specific report
Recorded
Report date
2026-06-02
Evidence checked
2026-09-22
£3.50per mg
£35.00per pack
View AnalysisBuy Now

Lowest Price per mg

Semax 30mgReta Research

Why this score?
Testing & analytical evidence
10/45
Value
25/25
Product identity
12/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Quantity
30 mg / vial
Testing evidence
Evidence status
Testing claimed
Manufacturer statement
Lyophilised powder offered in 10mg and 30mg vials, ≥99% purity by HPLC, Certificate of Analysis on request. | Research-grade peptides, independently HPLC-tested and dispatched fast across the UK.
Laboratory
Not recorded
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
£1.50per mg
£45.00per pack
View AnalysisBuy Now
Product & testing details
Supplier
Reta Research
Vials per pack
1
Price per vial
£45.00
Listing last checked
2026-09-22 11:04:33
Evidence status
Testing claimed
Manufacturer statement
Lyophilised powder offered in 10mg and 30mg vials, ≥99% purity by HPLC, Certificate of Analysis on request. | Research-grade peptides, independently HPLC-tested and dispatched fast across the UK.
Laboratory
Not recorded
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22

Semax 30mg

Reta Research
Why this score?
Testing & analytical evidence
10/45
Value
25/25
Product identity
12/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Testing evidence
Evidence status
Testing claimed
Manufacturer statement
Lyophilised powder offered in 10mg and 30mg vials, ≥99% purity by HPLC, Certificate of Analysis on request. | Research-grade peptides, independently HPLC-tested and dispatched fast across the UK.
Laboratory
Not recorded
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
£1.50per mg
£45.00per pack
View AnalysisBuy Now

Compare research products

Vial size
Research peptide product comparison
#ProductQuantityPrice / vialPrice / mgTestingScore
1Semax 10mgPepSource10 mg / vial£35.00per vial£3.50per mgTesting evidence
Evidence status
Verified independent evidence
Manufacturer statement
"Every batch is independently third-party tested for HPLC purity and mass-spectrometry identity, and the certificate of analysis for the batch you receive is published on our lab results page." "Purity: Verified by HPLC on every batch — the measured figure for your lot is published on its certificate of analysis"
Laboratory
Freedom Diagnostics Testing
Certification body
Not recorded
Batch
XA10-2606-02-IV
Batch-specific report
Recorded
Report date
2026-06-02
Evidence checked
2026-09-22
Why this score?
Testing & analytical evidence
40/45
Value
13/25
Product identity
14/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.		Buy Now
2Semax 10mgUK Peptides (ukpeptides.org)10 mg / vial£24.99per vial£2.50per mgTesting evidence
Evidence status
Verified independent evidence
Manufacturer statement
Independently tested · accredited external lab · lot-matched CoAs published · third-party test report for Semax 10mg · ≥98% HPLC · independently verified by an accredited independent laboratory via HPLC-UV.
Laboratory
MZ Biolabs
Certification body
Not recorded
Batch
2026-07-15
Batch-specific report
Recorded
Report date
2026-07-31
Evidence checked
2026-09-22
Why this score?
Testing & analytical evidence
36/45
Value
18/25
Product identity
11/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.		Buy Now
3Semax 10-mg / owsa-semax-10mgOwsa Labs10 mg / vial£19.99per vial£2.00per mgTesting evidence
Evidence status
Verified independent evidence
Manufacturer statement
"Certificate of analysis on every product"; "We hold 1 laboratory report for this compound. It covers the lot it names, so check the lot number on your vial against the list below."; "Testing by Janoshik Analytical, covering peptide content and purity."; "Commissioned by Yiwu Aozuo Trading Firm (manufacturer), not by Owsa Labs."
Laboratory
Janoshik Analytical
Certification body
Not recorded
Batch
XA10/202608
Batch-specific report
Recorded
Report date
2026-08-11
Evidence checked
2026-09-22
Why this score?
Testing & analytical evidence
39/45
Value
21/25
Product identity
11/15
Supplier transparency
3/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.		Buy Now
4Semax 30mgReta Research30 mg / vial£45.00per vial£1.50per mgTesting evidence
Evidence status
Testing claimed
Manufacturer statement
Lyophilised powder offered in 10mg and 30mg vials, ≥99% purity by HPLC, Certificate of Analysis on request. | Research-grade peptides, independently HPLC-tested and dispatched fast across the UK.
Laboratory
Not recorded
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
Why this score?
Testing & analytical evidence
10/45
Value
25/25
Product identity
12/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.		Buy Now
5Semax 10mgReta Research10 mg / vial£30.00per vial£3.00per mgTesting evidence
Evidence status
Testing claimed
Manufacturer statement
Lyophilised powder offered in 10mg and 30mg vials, ≥99% purity by HPLC, Certificate of Analysis on request.
Laboratory
Not recorded
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
Why this score?
Testing & analytical evidence
10/45
Value
15/25
Product identity
12/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.		Buy Now
6Semax 5-mg / owsa-semax-5mgOwsa Labs5 mg / vial£16.99per vial£3.40per mgTesting evidence
Evidence status
Testing claimed
Manufacturer statement
Certificate of analysis on every product; Third-party tested; We hold 1 laboratory report for this compound. It covers the lot it names, so check the lot number on your vial against the list below. Testing by Janoshik Analytical, covering peptide content and purity.
Laboratory
Janoshik Analytical
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
Why this score?
Testing & analytical evidence
10/45
Value
14/25
Product identity
11/15
Supplier transparency
3/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.		Buy Now
#1

Semax 10mgPepSource

Why this score?
Testing & analytical evidence
40/45
Value
13/25
Product identity
14/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Quantity
10 mg / vial
Testing evidence
Evidence status
Verified independent evidence
Manufacturer statement
"Every batch is independently third-party tested for HPLC purity and mass-spectrometry identity, and the certificate of analysis for the batch you receive is published on our lab results page." "Purity: Verified by HPLC on every batch — the measured figure for your lot is published on its certificate of analysis"
Laboratory
Freedom Diagnostics Testing
Certification body
Not recorded
Batch
XA10-2606-02-IV
Batch-specific report
Recorded
Report date
2026-06-02
Evidence checked
2026-09-22
£3.50per mg
£35.00per pack
View AnalysisBuy Now
Product & testing details
Supplier
PepSource
Vials per pack
1
Price per vial
£35.00
Listing last checked
2026-09-22 11:04:33
Evidence status
Verified independent evidence
Manufacturer statement
"Every batch is independently third-party tested for HPLC purity and mass-spectrometry identity, and the certificate of analysis for the batch you receive is published on our lab results page." "Purity: Verified by HPLC on every batch — the measured figure for your lot is published on its certificate of analysis"
Laboratory
Freedom Diagnostics Testing
Certification body
Not recorded
Batch
XA10-2606-02-IV
Batch-specific report
Recorded
Report date
2026-06-02
Evidence checked
2026-09-22
#2

Semax 10mgUK Peptides (ukpeptides.org)

Why this score?
Testing & analytical evidence
36/45
Value
18/25
Product identity
11/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Quantity
10 mg / vial
Testing evidence
Evidence status
Verified independent evidence
Manufacturer statement
Independently tested · accredited external lab · lot-matched CoAs published · third-party test report for Semax 10mg · ≥98% HPLC · independently verified by an accredited independent laboratory via HPLC-UV.
Laboratory
MZ Biolabs
Certification body
Not recorded
Batch
2026-07-15
Batch-specific report
Recorded
Report date
2026-07-31
Evidence checked
2026-09-22
£2.50per mg
£24.99per pack
View AnalysisBuy Now
Product & testing details
Supplier
UK Peptides (ukpeptides.org)
Vials per pack
1
Price per vial
£24.99
Listing last checked
2026-09-22 11:25:55
Evidence status
Verified independent evidence
Manufacturer statement
Independently tested · accredited external lab · lot-matched CoAs published · third-party test report for Semax 10mg · ≥98% HPLC · independently verified by an accredited independent laboratory via HPLC-UV.
Laboratory
MZ Biolabs
Certification body
Not recorded
Batch
2026-07-15
Batch-specific report
Recorded
Report date
2026-07-31
Evidence checked
2026-09-22
#3

Semax 10-mg / owsa-semax-10mgOwsa Labs

Why this score?
Testing & analytical evidence
39/45
Value
21/25
Product identity
11/15
Supplier transparency
3/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Quantity
10 mg / vial
Testing evidence
Evidence status
Verified independent evidence
Manufacturer statement
"Certificate of analysis on every product"; "We hold 1 laboratory report for this compound. It covers the lot it names, so check the lot number on your vial against the list below."; "Testing by Janoshik Analytical, covering peptide content and purity."; "Commissioned by Yiwu Aozuo Trading Firm (manufacturer), not by Owsa Labs."
Laboratory
Janoshik Analytical
Certification body
Not recorded
Batch
XA10/202608
Batch-specific report
Recorded
Report date
2026-08-11
Evidence checked
2026-09-22
£2.00per mg
£19.99per pack
View AnalysisBuy Now
Product & testing details
Supplier
Owsa Labs
Vials per pack
1
Price per vial
£19.99
Listing last checked
2026-09-22 11:04:33
Evidence status
Verified independent evidence
Manufacturer statement
"Certificate of analysis on every product"; "We hold 1 laboratory report for this compound. It covers the lot it names, so check the lot number on your vial against the list below."; "Testing by Janoshik Analytical, covering peptide content and purity."; "Commissioned by Yiwu Aozuo Trading Firm (manufacturer), not by Owsa Labs."
Laboratory
Janoshik Analytical
Certification body
Not recorded
Batch
XA10/202608
Batch-specific report
Recorded
Report date
2026-08-11
Evidence checked
2026-09-22
#4

Semax 30mgReta Research

Why this score?
Testing & analytical evidence
10/45
Value
25/25
Product identity
12/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Quantity
30 mg / vial
Testing evidence
Evidence status
Testing claimed
Manufacturer statement
Lyophilised powder offered in 10mg and 30mg vials, ≥99% purity by HPLC, Certificate of Analysis on request. | Research-grade peptides, independently HPLC-tested and dispatched fast across the UK.
Laboratory
Not recorded
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
£1.50per mg
£45.00per pack
View AnalysisBuy Now
Product & testing details
Supplier
Reta Research
Vials per pack
1
Price per vial
£45.00
Listing last checked
2026-09-22 11:04:33
Evidence status
Testing claimed
Manufacturer statement
Lyophilised powder offered in 10mg and 30mg vials, ≥99% purity by HPLC, Certificate of Analysis on request. | Research-grade peptides, independently HPLC-tested and dispatched fast across the UK.
Laboratory
Not recorded
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
#5

Semax 10mgReta Research

Why this score?
Testing & analytical evidence
10/45
Value
15/25
Product identity
12/15
Supplier transparency
10/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Quantity
10 mg / vial
Testing evidence
Evidence status
Testing claimed
Manufacturer statement
Lyophilised powder offered in 10mg and 30mg vials, ≥99% purity by HPLC, Certificate of Analysis on request.
Laboratory
Not recorded
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
£3.00per mg
£30.00per pack
View AnalysisBuy Now
Product & testing details
Supplier
Reta Research
Vials per pack
1
Price per vial
£30.00
Listing last checked
2026-09-22 11:04:33
Evidence status
Testing claimed
Manufacturer statement
Lyophilised powder offered in 10mg and 30mg vials, ≥99% purity by HPLC, Certificate of Analysis on request.
Laboratory
Not recorded
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
#6

Semax 5-mg / owsa-semax-5mgOwsa Labs

Why this score?
Testing & analytical evidence
10/45
Value
14/25
Product identity
11/15
Supplier transparency
3/10
Label & listing transparency
5/5
Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
Quantity
5 mg / vial
Testing evidence
Evidence status
Testing claimed
Manufacturer statement
Certificate of analysis on every product; Third-party tested; We hold 1 laboratory report for this compound. It covers the lot it names, so check the lot number on your vial against the list below. Testing by Janoshik Analytical, covering peptide content and purity.
Laboratory
Janoshik Analytical
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22
£3.40per mg
£16.99per pack
View AnalysisBuy Now
Product & testing details
Supplier
Owsa Labs
Vials per pack
1
Price per vial
£16.99
Listing last checked
2026-09-22 11:04:33
Evidence status
Testing claimed
Manufacturer statement
Certificate of analysis on every product; Third-party tested; We hold 1 laboratory report for this compound. It covers the lot it names, so check the lot number on your vial against the list below. Testing by Janoshik Analytical, covering peptide content and purity.
Laboratory
Janoshik Analytical
Certification body
Not recorded
Batch
Not recorded
Batch-specific report
Not established in this record
Report date
Not recorded
Evidence checked
2026-09-22

What is Semax?

Semax is a synthetic heptapeptide with the free-base sequence H-Met-Glu-His-Phe-Pro-Gly-Pro-OH. Structurally, the first four residues correspond to ACTH(4-7), while the C-terminal Pro-Gly-Pro sequence replaces the remaining residues that would appear in native ACTH(4-10). That is why publications use both ACTH(4-7)PGP and “ACTH(4-10) analogue” language. The verified public chemical record is PubChem CID 9811102. [S1] [S13]

Older publication titles that call Semax an ACTH(4-10) analogue describe its design relationship; they do not mean Semax has the same seven-residue sequence as native ACTH(4-10). [S1] [S13]

Semax and modified analogues must be kept separate

The parent compound Semax has free N- and C-termini. N-acetylation changes the N-terminus, while N-acetyl Semax amidate has both an N-terminal acetyl group and a C-terminal amide. A laboratory study found that N-terminal acetylation changed Semax metal coordination and biological behaviour in a cell model, demonstrating that terminal modification is not chemically trivial. PubChem separately records N-acetyl Semax amidate as Ac-MEHFPGP-NH2. Supplier terminology is inconsistent enough that a product name alone should not be treated as proof of identity. [S2] [S3] [S13] [S18]

NameVerified distinctionEvidence handling
SemaxH-MEHFPGP-OH; unmodified parent heptapeptide.Human Semax studies apply only where the studied material can reasonably be identified as Semax. [S1]
N-acetyl SemaxN-terminally acetylated Semax; chemically distinct from the parent. A 2016 laboratory study examined Ac-Semax.Do not transfer parent Semax clinical findings automatically. [S3]
N-acetyl Semax amidateAc-MEHFPGP-NH2; both N-terminal acetylation and C-terminal amidation.Treat as a separate analogue; direct human efficacy evidence was not located. [S2]
Semax acetateSalt form of the Semax active moiety; FDA treats it as a distinct bulk drug substance from free-base Semax.Do not assume formulation, quality or PK equivalence. [S13]
SelankDifferent heptapeptide: TKPRPGP, derived from a different parent sequence.Selank evidence is not Semax evidence. [S4] [S10]

PubChem currently lists "N-acetyl semax" as a synonym on the N-acetyl Semax amidate record. Acetylation and amidation are distinct chemical modifications, so the short product name alone is insufficient: check the stated terminal chemistry, sequence and analytical identity. [S2]

What does the research actually show?

Semax has a mixed evidence base. Human clinical reports mainly come from Russian neurological and ophthalmic settings, often with limited accessible methodological detail and little independent replication. Healthy-volunteer work is more recent but measures brain-network imaging rather than cognitive performance. Preclinical studies provide mechanistic signals involving BDNF, neurotrophin signalling, inflammatory gene expression and cerebral-ischaemia models, but these outcomes cannot establish clinical benefit in people. [S5] [S6] [S8] [S9] [S10] [S11] [S12]

Clinical populations

Russian studies report findings in ischemic stroke, optic-nerve disease and motor-neuron disease, but designs and outcomes vary and several source papers are accessible here only through English abstracts. [S5] [S6] [S7] [S8]

Limited human clinical evidence

Healthy volunteers

Two small human studies measured short-term resting-state functional connectivity after Semax exposure. They did not establish improved memory, attention, mood or everyday function. [S9] [S10]

Human mechanistic evidence

Animal research

Rat studies report changes in BDNF signalling, inflammatory gene expression and ischemia-related molecular pathways. [S11] [S12]

Preclinical

Marketing claims

Claims of broad cognitive enhancement, mood improvement or neuroprotection in healthy users go beyond what the controlled human evidence establishes. [S9] [S10] [S13] [S19]

Not established
Research areaWhat was measuredEvidence level
Acute ischemic strokeClinical neurological recovery and electrophysiology in Russian clinical reports.Human clinical; methodological limitations and limited accessible detail [S5]
Stroke rehabilitationBDNF, motor performance and Barthel index in 110 post-stroke patients.Human clinical; allocation/blinding unclear from abstract [S6]
Healthy-participant cognition claimsResting-state fMRI network changes, not validated memory or attention outcomes.Human mechanistic [S9] [S10]
Neurotrophin mechanismsBDNF protein/signalling changes in rat brain.Preclinical [S11]
Neuroinflammation mechanismsGene-expression changes in rat cerebral ischemia.Preclinical [S12]

A change in BDNF, gene expression or functional connectivity is a mechanistic finding. It is not interchangeable with a demonstrated improvement in cognition, recovery or quality of life.

Human evidence in people with diagnosed conditions

The available clinical literature is heterogeneous. In acute hemispheric ischemic stroke, a 1997 study compared 30 Semax-treated patients with 80 patients receiving conventional therapy and reported faster regression of neurological deficits, but the abstract does not describe random allocation or blinding. In 2018, 110 post-stroke rehabilitation patients were divided by rehabilitation timing and Semax exposure; the authors reported higher BDNF and better Barthel-index recovery with Semax. A 2007 motor-neuron-disease paper is indexed by PubMed as a randomized controlled trial, yet its own abstract describes an open-label sequential-group trial and reports no improvement in chronic denervation or clinical rating scales, although quality-of-life scores improved. [S5] [S6] [S7]

StudyPopulation / designKey limitation
Gusev et al. 199730 acute hemispheric ischemic-stroke patients receiving Semax plus intensive therapy; 80 conventionally treated controls.Russian article; abstract only; randomisation and blinding not established. [S5]
Gusev et al. 2018110 post-ischemic-stroke patients across early/late rehabilitation and Semax+/Semax- subgroups.Abstract does not establish randomisation or blinding; BDNF association is not proof of causal mechanism. [S6]
Serdiuk et al. 200727 motor-neuron-disease patients; open-label sequential groups with serial EMG and clinical scales.No benefit on chronic partial denervation or core clinical ratings; PubMed's RCT tag conflicts with the abstract's open-label description. [S7]
Polunin et al. 2000Optic-nerve disease patients divided into intranasal, endonasal-electrophoresis and control groups alongside basic therapy.Sample size not stated in accessible abstract; Russian article; concomitant therapy and limited design detail complicate attribution. [S8]

Clinical findings in stroke, optic-nerve disease or motor-neuron disease should not be presented as evidence of cognitive enhancement in healthy people.

Healthy-participant studies measured brain connectivity, not nootropic performance

The strongest directly relevant evidence for cognitively healthy participants is neuroimaging rather than performance testing. A 2018 study included 24 healthy volunteers: 14 received intranasal Semax and 10 placebo, with resting-state fMRI before and shortly after exposure. The authors reported a larger rostral default-mode-network subcomponent in the Semax group. A 2020 study assessed 52 healthy participants receiving Semax, Selank or placebo and reported differences in functional connectivity involving the right amygdala and temporal regions. Neither accessible abstract reports improved memory, attention, reaction time, mood or academic/work performance. [S9] [S10]

2018 default-mode study

24 healthy volunteers; Semax versus placebo; resting-state fMRI endpoint. [S9]

Small human imaging study

2020 connectomics study

52 healthy participants; Semax, Selank or placebo; resting-state connectivity before and shortly after exposure. [S10]

Human imaging study

What these studies do not show

The abstracts do not demonstrate improved cognitive test performance, sustained attention, mood benefit or functional outcomes. [S9] [S10]

Outcome limitation

The older 1997 developer-group review asserts improved memory and attention in healthy men under extreme conditions, but it is a narrative summary rather than an independently replicated controlled trial and should not be used as stand-alone proof. [S19]

Mechanistic findings are mainly preclinical

Mechanistic interest in Semax includes neurotrophin signalling and inflammatory pathways. In rats, Semax increased BDNF protein in basal forebrain and specific binding of radiolabelled Semax was reported. Other rat cerebral-ischaemia studies found altered expression of immune-response genes after Semax treatment. These findings help generate hypotheses about how Semax might act, but animal gene-expression and protein changes do not establish clinical neuroprotection or cognitive enhancement in humans. [S11] [S12]

BDNF signalling

Rat studies report increased BDNF-related signalling after Semax. [S11]

Animal evidence

Inflammatory gene expression

Rat ischemia models report Semax-associated changes in genes involved in immune and inflammatory pathways. [S12]

Animal evidence

Clinical interpretation

Mechanistic biomarkers can support biological plausibility but cannot establish that the same pathway causes a meaningful human outcome. [S11] [S12] [S13]

Do not over-extrapolate

Do not describe BDNF increases or transcriptomic changes as proven 'brain repair' in people.

Registered-trial evidence is limited

No Semax study was located in the targeted ClinicalTrials.gov searches performed for this review. FDA's 2026 review also searched ClinicalTrials.gov alongside PubMed, Embase and Cochrane and based its human assessment on published or submitted literature rather than a modern registered development programme. The absence of a ClinicalTrials.gov record does not prove that no study has ever occurred in another national system, but it means the historical Russian literature cannot be treated as if it were a contemporary prospectively registered trial portfolio. [S13]

No trial record is populated in the structured `research.trials` array because no verified Semax registry entry was located in the search performed.

Safety is incompletely characterised

FDA's 2026 review concluded that there was insufficient clinical information to characterise the safety profile of Semax free base or Semax acetate. FDA found no human pharmacokinetic studies by any route and no safety data for the proposed subcutaneous route; the human literature it reviewed was intranasal. Most cited clinical references did not discuss adverse events. FDA also identified quality concerns around inconsistent naming, impurities, aggregation, microbial quality and potential immunogenicity, particularly where injectable or compounded products are proposed. [S13]

Human safety database

Small and inconsistently reported; many historical clinical papers do not provide detailed adverse-event reporting. [S13]

Limited

Human pharmacokinetics

No human pharmacokinetic study for Semax free base or Semax acetate was located by FDA's 2026 review. [S13]

Not established

Product-quality risks

Peptide impurities, aggregation, microbial quality and endotoxin control can matter independently of a headline purity percentage. [S13]

Product-specific

Analogue uncertainty

Safety findings for unmodified Semax cannot establish the safety of N-acetyl or amidated analogues. [S2] [S3]

Separate compounds

FDA's compounding review is a US regulatory assessment, not a UK approval decision, but its evidence review is useful for identifying gaps in human PK, safety reporting and product characterisation. [S13]

Formulation and route cannot be assumed equivalent

Human Semax literature located for FDA's safety review involved intranasal administration, while UK research suppliers may sell lyophilised powder or prepared research solutions. FDA separately evaluated Semax free base and Semax acetate because they are distinct bulk drug substances, and it noted that historical clinical references often do not specify which was used. FDA did not locate human pharmacokinetic studies by any route. Accordingly, no verified human half-life should be assigned to generic Semax listings, and evidence from a Russian medicinal nasal formulation should not be transferred to a research vial or another route. [S13] [S17]

Form / routeEvidence contextEditorial rule
Russian medicinal nasal dropsFDA reports registered 0.1% and 1% nasal-drop products in Russia.Do not assume equivalence to UK research products. [S13]
Semax free baseVerified parent active moiety; FDA evaluates it separately from acetate.Record exact form where disclosed. [S1] [S13]
Semax acetateSalt form with distinct bulk-drug-substance identity.Do not silently merge with free-base product data. [S13]
Lyophilised research vial / prepared research solutionObserved UK supplier presentations.Presentation does not establish equivalence to a studied medicinal formulation. [S17]
Other routesNo human PK study located by FDA and no subcutaneous safety literature located in its review.Do not infer PK, safety or efficacy across routes. [S13]

Do not publish commonly repeated online half-life figures as verified human pharmacokinetics unless a primary human PK source is located.

UK and foreign regulatory context

UK guidance is unusually explicit for Semax: the Food Standards Agency states that MHRA considers Semax a medicine rather than a food and that it may only be sold or supplied in the UK as a medicine where an appropriate marketing authorisation has been granted. The MHRA product-information service is the public route for authorised-medicine information, and the site's targeted search did not locate a Semax marketing-authorisation record. MHRA also operates controlled routes for certain unlicensed medicines supplied for individual clinical need; that does not make a research-use supplier vial an authorised medicine. [S14] [S15] [S16]

United Kingdom

FSA guidance states MHRA considers Semax a medicine rather than food; authorised medicinal supply requires the relevant UK marketing authorisation. [S14] [S15]

UK regulatory guidance

Russia

FDA's 2026 review, citing the Russian State Register of Medicines, reports that Semax is a registered drug in Russia and is available as 0.1% and 1% nasal drops. [S13]

Foreign registration

What foreign registration does not prove

Russian registration does not create UK approval, validate modified analogues or establish equivalence to research-use vials sold by third parties. [S13] [S14] [S17] [S18]

Jurisdictions differ

The Russian register was not independently machine-accessible in this research session. The foreign-status statement therefore follows FDA's 2026 regulatory review, which cites the Russian State Register and notes that translation is required. Exact Russian authorised indications are not asserted here because they were not independently verified. [S13]

How to interpret Semax research-product listings

For Semax, identity is unusually important because the same market category contains unmodified Semax, salts and terminally modified analogues. A credible listing should state the exact compound, sequence or terminal modifications where relevant, labelled quantity, physical presentation and batch-specific analytical evidence. A purity percentage alone does not establish that the main chromatographic peak is the intended Semax molecule, and neither purity nor mass-spectrometric identity establishes sterility, endotoxin control, medicinal quality or suitability for human use. [S1] [S2] [S13] [S17] [S18]

Exact identity

Record Semax free base, Semax acetate, N-acetyl Semax, N-acetyl Semax amidate or unresolved identity rather than collapsing them into one 'Semax' field. [S1] [S2] [S3] [S13]

Identity first

Labelled quantity

Record the supplier's stated amount separately from purity and independently measured content. [S17] [S18]

Separate data field

Analytical evidence

Check method, expected mass/identity, purity result, laboratory, batch match and report date. HPLC purity alone is not an identity test. [S13] [S18]

Method matters

Research-use label

A 'research use only' statement does not make the product equivalent to a registered medicinal nasal formulation or establish suitability for administration. [S14] [S17] [S18]

Not a medicine approval
Listing fieldWhat should be verifiedIf missing
Compound nameExact parent/analogue/salt identity.Show identity as unresolved. [S1] [S2] [S13]
Sequence / terminal chemistryMEHFPGP with free termini for parent Semax; explicit modifications for analogues.Do not infer from marketing shorthand. [S1] [S2] [S3]
Labelled quantityDeclared amount per vial/bottle.Keep unknown rather than estimating. [S17] [S18]
Purity and identity testingBatch-specific analytical method, result, expected analyte/mass and laboratory.Do not convert a generic purity claim into verified identity. [S13] [S18]
Medicinal equivalenceEvidence would need to match the exact authorised/studied formulation.Do not infer from a research-use product name. [S13] [S14] [S17] [S18]

The future product model should include an explicit `compound_form` or `analogue_identity` field; a single generic 'peptide' name is not sufficient for Semax-family products.

Frequently asked questions

What is Semax?

Semax is a synthetic seven-amino-acid peptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It contains the ACTH(4-7) sequence followed by Pro-Gly-Pro. [S1] [S13]

Is Semax the same as ACTH(4-10)?

No. Semax is often described as an ACTH(4-10) analogue, but its verified sequence is ACTH(4-7) followed by Pro-Gly-Pro. It is therefore structurally related to, but not identical with, native ACTH(4-10). [S1] [S13]

Is N-acetyl Semax the same as Semax?

No. N-terminal acetylation changes the molecule. A laboratory study found altered metal-binding and biological properties after acetylation, so parent-Semax findings should not automatically be transferred to the acetylated analogue. [S3]

Is N-acetyl Semax amidate the same as N-acetyl Semax?

Not chemically. N-acetyl Semax amidate has both an N-terminal acetyl group and a C-terminal amide. Because market terminology is inconsistent, the exact terminal chemistry and analytical identity should be checked rather than inferred from the short name. [S2] [S3] [S18]

Does Semax improve memory or focus in healthy people?

That has not been established by the best accessible controlled human evidence. Small healthy-volunteer studies reported changes in resting-state brain connectivity, but their abstracts do not report validated improvements in memory, attention or functional performance. [S9] [S10] [S19]

Has Semax been studied in stroke patients?

Yes. Russian clinical studies reported neurological and rehabilitation findings in ischemic-stroke populations. However, several papers are accessible here only through English abstracts, and important design details such as randomisation and blinding are often unclear or absent. [S5] [S6]

What does BDNF research tell us about Semax?

Rat studies report Semax-related changes in BDNF protein or signalling, and one human stroke-rehabilitation study measured plasma BDNF. These findings are mechanistic or biomarker evidence and do not by themselves prove cognitive enhancement or neuroprotection in people. [S6] [S11]

What is the human half-life of Semax?

A verified human pharmacokinetic half-life was not located. FDA's 2026 review specifically states that it could not find human pharmacokinetic studies for Semax free base or Semax acetate by any route. [S13]

Is Semax approved in the UK?

UK Food Standards Agency guidance states that MHRA considers Semax a medicine rather than a food and that it may only be sold or supplied as a medicine where an appropriate UK marketing authorisation has been granted. The targeted MHRA product-information search for this review did not locate a Semax marketing-authorisation record. [S14] [S15]

Is Semax an authorised medicine in Russia?

FDA's 2026 regulatory review, citing the Russian State Register of Medicines, reports that Semax is a registered drug in Russia and is available as 0.1% and 1% nasal drops. That foreign registration does not establish UK approval or equivalence to research-use products. [S13] [S14]

Is Selank the same as Semax?

No. Selank is a separate heptapeptide with the sequence TKPRPGP. It has its own evidence base and should not be treated as another name for Semax. [S4] [S10]

Sources & methodology

We separate animal models, observational human studies and ongoing trials. Scientific evidence is assessed independently of future supplier documentation. How we verify testing →

Page updated: Sources checked: 22 September 2026

Testing evidence in this comparison

  • Verified independent evidence: 3
  • Testing claimed: 3

What does Semax cost?

Lowest: £1.50 / mg · Median: £2.75 / mg · Highest: £3.50 / mg