Crystagen
A Khavinson tripeptide bioregulator marketed for thymic and immune support, taken as short oral courses a few times a year.
Also known as EDP, Glu-Asp-Pro, immune bioregulator tripeptide, Crystagen
Anecdotal — Community reports without controlled evidence. Treat the confident dosing charts accordingly.
The weakest evidence in this class. Crystagen sits inside the Khavinson bioregulator framework and inherits its general animal data, but there is essentially no compound-specific published research, no controlled human trial, and no independent verification of the proposed mechanism.
How it works
Crystagen is Glu-Asp-Pro, developed within the Khavinson short-peptide programme as the immune-system member of the tripeptide 'cytogen' series. The programme's stated mechanism is that these tripeptides penetrate cell and nuclear membranes and interact with specific DNA sequences to modulate transcription of tissue-specific genes - in this case genes governing thymic epithelium and lymphocyte function. Reported effects include normalisation of T-cell subsets, improved lymphocyte proliferative response and reduced infection susceptibility in aged animals. Be clear about the standard of proof: the DNA-binding model comes from the originating group, independent mechanistic replication is thin, and the human data are small Russian clinical series rather than controlled trials.
Targets: Thymic epithelium, Lymphocyte function, Proposed gene promoter binding
Dosing
| Protocol | Dose | Frequency | Route |
|---|---|---|---|
| Standard oral courseMorning, 10-15 minutes before food. | 10 mg – 20 mg | one to two capsules daily | oral |
| Injectable research protocolMorning. | 100 mcg – 500 mcg | once daily for 10 days | subcutaneous |
- · Marketed capsules are typically 10 mg, taken once or twice daily for 10-30 days. Actual peptide content per capsule varies between suppliers and is often not verifiable.
- · Following the general Khavinson injectable pattern used for Vilon and similar peptides. No formal dosing has been established for the injectable form of this specific tripeptide.
Cycling
Ten to thirty days on, then several months off, repeated two to three times per year. Continuous dosing is not the intended model for this family.
Pharmacology
- Half-life
- Not characterised. As an oral tripeptide it is largely hydrolysed during digestion, which is one of the unresolved problems with the oral bioregulator concept.
- Onset
- Courses are 10-30 days; effects are described over that timescale rather than acutely.
- Routes
- oral, subcutaneous
- Molecule
- Synthetic tripeptide (Khavinson short peptide bioregulator)
- Sequence length
- 3 amino acids
- Molecular weight
- 359.3 Da
Handling
- Diluent
- Bacteriostatic water
- Typical mix
- 2 or 3 mL
- Lyophilised
- Room temperature for capsules; refrigerate lyophilised powder for long-term storage.
- Reconstituted
- Refrigerated, use within about 30 days.
- Light sensitive
- Yes — keep it out of the light
Mixing
Only relevant to the research injectable form; the commercial product is an oral capsule with nothing to reconstitute.
Side effects
- commonNo consistent adverse effects reported— Honest framing: the safety record reflects an absence of systematic study, not a demonstrated absence of risk.
- uncommonMild digestive upset with capsules
Do not use if
- Pregnancy and breastfeeding - no data.
- Active malignancy, given unquantified effects on cell proliferation and gene expression.
Combining it
- redundantvilon — Both are Khavinson immune/thymic bioregulators with overlapping claims.
- redundantthymalin — Same programme, same target tissue, thymalin has the better human data of the two.
What to monitor
- · CBC with differential before and after a course if you want any objective readout.
- · No validated biomarker exists for this compound.
Legal status
Sold as a supplement in Russia and online elsewhere; not an approved drug in any Western market.
References
- Khavinson, peptide bioregulators and gene expression, programme review (review)
- Khavinson short peptide 'cytogen' series descriptive literature (other)
Mechanism in depth
There is no compound-specific mechanism to report, and saying so is more useful than constructing one. Crystagen is the immune-system member of the Khavinson tripeptide 'cytogen' series, and everything written about its mechanism is inherited from the programme's general model - that short peptides penetrate cell and nuclear membranes and interact with specific DNA sequences to modulate transcription of tissue-specific genes. That model is set out most fully in the 2021 Molecules systematic review from the originating group. The theoretical objection is the same as for Vilon and it is stronger here only in the sense that three residues still provide very little information content for sequence-specific DNA recognition. Unlike Vilon, which has indexed rodent lifespan and tumour-incidence data, Crystagen has essentially no compound-specific published research at all. What exists in vendor material - normalisation of T-cell subsets, improved lymphocyte proliferative response, reduced infection susceptibility in aged animals - is programme-level narrative applied to this particular tripeptide rather than findings generated with it. Treat any detailed pathway description for Crystagen as invented.
What usually goes wrong
Nothing observable, which is both the practical outcome and the core problem. There is no biomarker, no compound-specific literature and no way to tell whether a course did anything. The specific consumer risk here is product content: marketed capsules are typically labelled 10 mg, actual peptide content varies between suppliers and is frequently not verifiable, and some products in this category contain animal-derived extract rather than the synthetic tripeptide. The contraindications in the Core entry - pregnancy, active malignancy - are inferred from the claimed gene-expression and proliferation effects rather than from observed harm, because nobody has looked. That is not the same as a clean safety record and should not be read as one.
Bloodwork worth running
| Marker | When | Why it matters |
|---|---|---|
| CBC with differential | Baseline and at the end of a 10-30 day course. | The only objective readout available. Take it before and after a course so that you have something other than impression to reason from, given there is no biomarker and no compound-specific literature.Act if: No established threshold. Any change smaller than routine biological variation in lymphocyte counts should be treated as noise. |
Pharmacokinetics
- Metabolism
- Hydrolysis to free L-glutamate, L-aspartate and L-proline.
- Elimination
- Amino acid recycling.
Receptor targets
- Genomic DNA promoter regions (proposed by the originating programme, not confirmed) — No binding data exist for this tripeptide
Proposed transcriptional modulation of genes governing thymic epithelium and lymphocyte function. This is a programme-level model, not a compound-specific finding.
What to expect, and when
Minutes: an oral tripeptide is hydrolysed during digestion. Days 10-30: the course length, during which nothing is expected to be perceptible. Weeks to months: the model assumes effects that outlast the dosing period, so this is where any claimed benefit would sit. Two to three courses a year: the intended pattern. No acute effect exists and no timeline for this specific compound has ever been established in a study.
Stacking and comparisons
Crystagen, Vilon and Thymogen are three short peptides making overlapping claims on the same tissue with, between them, one indexed body of primary data. Running all three is buying the same story three times. Thymalin has better human data than Crystagen within the same programme, and thymosin alpha-1 has better data than all of them combined. Crystagen is typically taken inside a broader Khavinson-style stack alongside Epitalon and other cytogens; that pattern is convention and has never been tested as a combination. There is nothing evidence-based to say about interactions because there is nothing evidence-based to say about the compound.
Crystagen has the weakest evidence base of anything in this class, and that includes the interferon mimetics, which at least have indexed preclinical publications describing specific molecules. Against Vilon, its closest sibling, Vilon has indexed English-language rodent lifespan and tumour-incidence papers and Crystagen has none. Against Thymogen, Thymogen has a state registration with a defined label, a defined dose and an internationally indexed mechanistic paper. Against thymalin, thymalin has the better human data within the same research programme. Against thymosin alpha-1 there is no comparison to make. If the Khavinson framework appeals to you and you are going to take something from it for immune purposes, Vilon is the better-documented choice and thymalin the better-evidenced one.
Rough cost
$30–$70/month. Retail pricing for marketed 10 mg capsules over a 10-30 day course. Because dosing is pulsed two to three times a year, the annual cost is far below this monthly figure. Supplement-market observation rather than a verified survey.
Genuinely uncertain
- No compound-specific published research was located for Crystagen. Every mechanistic claim in circulation is programme-level narrative applied to this tripeptide.
- No pharmacokinetics of any kind exist by any route.
- Whether an oral tripeptide delivers any intact peptide past the gut is unresolved and theoretically doubtful.
- The DNA-binding mechanism is the originating group's model and has no independent structural or biochemical confirmation for any member of the series, let alone this one.
- Actual peptide content of marketed capsules is frequently unverifiable, and some products in this category contain animal-derived extracts rather than the synthetic tripeptide.
- The 100-500 mcg injectable range in the Core record is extrapolated from the general Khavinson injectable pattern used for Vilon. No dosing has ever been established for an injectable form of this specific tripeptide.
- The sequence is marked verified on the basis that Glu-Asp-Pro residue masses reconcile exactly with the quoted 359.3 Da molecular weight - an internal consistency check, not confirmation against a primary structural source.
Papers
- Peptide Regulation of Gene Expression: A Systematic Review Khavinson VK, Popovich IG, Linkova NS, et al., Molecules, 2021 · PMID 34834147
The programme-level case for the short peptide bioregulator model. Cited here because it is the framework Crystagen belongs to, not because it contains data on Crystagen itself.
- Peptide Regulation of Cell Differentiation Khavinson V, Linkova N, Dyatlova A, et al., Stem Cell Reviews and Reports, 2020 · PMID 31808038
Same programme, differentiation arm. Again, framework rather than compound-specific evidence.