Adamax

Adamax is the name given in the research-chemical market to a synthetic derivative of Semax (Met-Glu-His-Phe-Pro-Gly-Pro) that carries an adamantane group. Adamantane is a rigid, cage-shaped C10H16 hydrocarbon used widely in medicinal chemistry, most familiarly in amantadine and memantine, to raise lipophilicity and resistance to metabolic breakdown [1]. The stated design intent behind Adamax is therefore straightforward: take the Semax heptapeptide, which is a peptide with a short residence time in tissue, and attach a lipophilic anchor to prolong its persistence. What is not straightforward is the evidence. Descriptions of the exact structure differ between suppliers — some describe an adamantane-conjugated Semax heptapeptide, others a nine-residue acetylated and amidated variant — and at the time of writing there is no PubChem entry, no peer-reviewed synthesis or characterisation paper, and no indexed pharmacology study that names Adamax. For that reason this listing gives no molecular formula, weight or CID, and the mechanistic discussion below concerns the Semax parent, not Adamax itself.

What the parent compound is

Semax is an analogue of the N-terminal fragment 4-7 of adrenocorticotropic hormone (Met-Glu-His-Phe) joined to a Pro-Gly-Pro tail that protects against aminopeptidase and carboxypeptidase attack. It was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences and is registered as a medicine in Russia; it has no FDA or EMA approval. Its principal reported pharmacology in rodents is neurotrophic and neuroprotective rather than melanocortin-receptor-mediated in the classical sense, and it lacks the corticotropic activity of full-length ACTH.

Mechanism reported for Semax

The most cited mechanism is up-regulation of brain-derived neurotrophic factor (BDNF) signalling. In rats, a single application of Semax produced a maximal 1.4-fold increase in hippocampal BDNF protein, a 1.6-fold increase in TrkB tyrosine phosphorylation, and 3-fold and 2-fold increases in exon III BDNF and TrkB mRNA respectively [2]. A separate study showed specific binding of Semax to rat basal forebrain membranes with an accompanying rise in BDNF protein [3]. Transcriptome profiling in a rat ischaemia-reperfusion model identified 394 differentially expressed genes 24 hours after Semax, with inflammation-related transcripts suppressed and neurotransmission-related transcripts activated [4]. A 2024 chronic-unpredictable-stress study in male rats reported that low-dose Semax attenuated anhedonia, adrenal hypertrophy and the fall in hippocampal BDNF, but had no effect on forced-swim immobility [5].

Why an adamantane modification might matter

The rationale for Adamax rests on the pharmacokinetics of the parent. Semax is degraded in the presence of rat basal forebrain cell cultures and plasma membranes, with cleavage products that include the Pro-Gly-Pro tripeptide and shorter fragments [6]. Adamantane derivatisation is a well-documented strategy for increasing the lipophilicity, membrane permeability and metabolic stability of small molecules and peptides [1]. Whether this strategy actually improves the half-life, brain penetration or activity of Semax has not been tested in any published study; the premise is chemically plausible but experimentally unverified.

What the research does not establish

There is no peer-reviewed evidence on Adamax. Its structure has not been published in an indexed journal, its purity and identity have not been independently characterised, and no in-vitro or in-vivo study has compared it with Semax on any endpoint. Claims that it is longer-acting, more potent or more brain-penetrant than Semax are inferences from general adamantane chemistry, not measurements. Even for the Semax parent, the evidence is predominantly Russian-language, produced by the originating institute, and based on rodent studies and small unblinded clinical series; no large randomised placebo-controlled trial exists in Western journals. Researchers working with Adamax should treat it as an uncharacterised analogue, verify identity and purity analytically before use, and should not assume that Semax literature transfers to it. This material is supplied for in-vitro laboratory research only.

Format. Lyophilised white to off-white powder in a sealed glass vial with rubber stopper and aluminium crimp cap. Because no independent reference standard exists, laboratories are advised to confirm identity and purity by HPLC or mass spectrometry before experimental use.

Reconstitution. Add bacteriostatic water slowly down the side of the vial and swirl gently until dissolved; do not shake. The adamantane group increases lipophilicity, so dissolution may be slower than for unmodified Semax. Use the reconstitution calculator to convert vial content to a working concentration.

Storage. Lyophilised vials: 2–8 °C, protected from light; suitable for longer-term storage at −20 °C. Reconstituted solution: 2–8 °C and use within 14 days; avoid repeated freeze–thaw cycles.

Handling. Wear gloves and eye protection; avoid generating dust from the lyophilised cake. Contains a methionine residue susceptible to oxidation; minimise air exposure of solutions. For in-vitro laboratory research only — not for human or veterinary use.