Compounds › Verified against primary sources

Neuro — the acetylated forms and the ones that stopped at phase 3

Semax and Selank "N-acetyl amidate" have 6 and 2 articles and zero registered studies. Rapastinel had 10 phase 3 trials and was abandoned; davunetide did not beat placebo

Not approvedVerified against primary sources

AI-generated illustration. Not data, and not an image from a study.

Experimental material. Read before using anything from here.

Nothing on this page is a medical recommendation, prescription or treatment plan. It is an organized translation of protocols circulating in research communities and, where it exists, of what published trials tested. The two are marked differently — and they are not equivalent.

Most of the compounds here have no FDA approval for human use. Several are sold labeled "research use only", which means they have not gone through purity, sterility or dosage controls for human consumption. A community-reported dose is not a validated dose: it is what someone reported having done.

Talk to a licensed health professional before considering any of these compounds. If you already use one and feel anything unexpected, seek care — do not wait for the next routine test.

Specific caution for this compound: None of these compounds has a product registered in Brazil or with any other agency. Two of them were seriously tested and did not become drugs. What is bought under these names is sold as a research reagent, with no control over purity, sterility or dose.

Summary

The acetylated versions of Semax and Selank, sold as more potent, and three neurological peptides that got further: rapastinel (GLYX-13), davunetide (NAP) and colivelin. The ones that went furthest are precisely the ones that show what usually happens next: program terminated, or a negative trial.

The "stronger" versions and the ones that were actually tested

This site has Semax, Selank, the Semax evidence and the neuro and cognition page. Missing were the N-acetylated and "amidated" forms of Semax and Selank, sold as more potent versions, and three peptides that got further: rapastinel, davunetide and colivelin.

A method caveat: the acetylated forms have no official name, and each seller spells them differently. The search gathers the spellings I found — N-acetyl semax, NA-Semax, N-acetylsemax, semax amidate — and the same for Selank. If there is a spelling I didn't see, the number may be low; it cannot be high.

No number on this page came from the site's secondary source.

How much evidence exists, compound by compound

The numbers below were gathered by me on October 5, 2026, on PubMed and ClinicalTrials.gov. Each row's query is written out in full, next to the number, so anyone can repeat it and contradict me — and so the script that rechecks this site's counts can run all of them.

The condition column is not a claim about mechanism: it is the Condition field copied from the largest phase 3 record that the search itself returned. When there is no phase 3 record, the cell says so.

Compound	Condition in phase 3 registrations	Query	Articles in PubMed	Studies on ClinicalTrials.gov
N-acetyl Semax (and amidate)	no phase 3 registration in this search	`"N-acetyl semax" OR "NA-Semax" OR "N-acetylsemax" OR "semax amidate"`	6	0
N-acetyl Selank (and amidate)	no phase 3 registration in this search	`"N-acetyl selank" OR "NA-Selank" OR "selank amidate"`	2	0
Rapastinel (GLYX-13)	Depressive Disorder, Major	`rapastinel OR "GLYX-13"`	109	19
Davunetide (NAP)	Progressive Supranuclear Palsy	`davunetide OR "AL-108" OR NAPVSIPQ OR "NAP peptide"`	244	5
Colivelin	no phase 3 registration in this search	`colivelin`	190	0

What exists in phase 3, and who it belongs to

An article count measures academic attention, not outcome evidence. The table below separates what has a registered phase 3 trial — and shows the largest record the search returned, with the declared number of participants and the sponsor. A registration is not a result.

Compound	Query	Registered phase 3 trials	The largest registration I opened
N-acetyl Semax (and amidate)	`("N-acetyl semax" OR "NA-Semax" OR "N-acetylsemax" OR "semax amidate") AND AREA[Phase]PHASE3`	0	—
N-acetyl Selank (and amidate)	`("N-acetyl selank" OR "NA-Selank" OR "selank amidate") AND AREA[Phase]PHASE3`	0	—
Rapastinel (GLYX-13)	`(rapastinel OR "GLYX-13") AND AREA[Phase]PHASE3`	10	NCT02951988 · n = 1,304 · Naurex, Inc, an affiliate of Allergan plc Depressive Disorder, Major
Davunetide (NAP)	`(davunetide OR "AL-108" OR NAPVSIPQ OR "NAP peptide") AND AREA[Phase]PHASE3`	1	NCT01110720 · n = 313 · Allon Therapeutics Progressive Supranuclear Palsy
Colivelin	`(colivelin) AND AREA[Phase]PHASE3`	0	—

Where the numbers don't add up

The "more potent" versions have 6 and 2 articles, and zero registered studies. The claim, which appears in the store, that the acetylated form crosses the blood-brain barrier better or lasts longer has no trial in people to support it.
Rapastinel is the one that went furthest, and it was abandoned. 10 phase 3 trials in major depression, the largest with 1,304 participants. 7 records were terminated; in 5, the declared reason is a business decision to stop the program. In the others, the sponsor was bought by another company or the participants moved to another study.
Davunetide reached phase 2/3 and did not work. The trial in progressive supranuclear palsy, with 313 participants, published in Lancet Neurology in 2014, found no difference versus placebo in either of the two primary endpoints. The authors' own conclusion: it is not an effective treatment for the disease. There were more nosebleeds in the davunetide group.
Colivelin has 190 articles and 0 registered studies. No trial registration in people, of any phase.

In Brazil

I searched every active ingredient in the open data on registered medicines in Brazil, downloaded on October 5, 2026 — 43,596 rows, counting only Active status, in the active ingredient and in the product name, ignoring accents and case. The therapeutic class is the one the dataset itself declares.

The acetylated forms and colivelin are left out of the table: they have no active ingredient name to look up.

Active ingredient	Search pattern	Active registrations	Declared therapeutic class	Products
Rapastinel (GLYX-13)	`RAPASTINEL`	0	—	—
Davunetide (NAP)	`DAVUNET`	0	—	—

References

This page did not come from the secondary source. All counts on this page were gathered by me on October 5, 2026, with the query declared next to each number. The method caveats are written in the first section, before the tables. This page was fact-checked on its own day, and that's why it carries its own date.

← Back to all compounds