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Thymogen

Khavinson bioregulator

Also: Thymagen · Timogen · oglufanide · oglufanide disodium · IM862 · EW · Glu-Trp · alpha-glutamyl-tryptophan · L-glutamyl-L-tryptophan · Тимоген

CautionImmuneRecovery & healingInjection / Nasal / Oral

Russian-registered immunostimulant dipeptide Glu-Trp; grey-market vials are dosed 10-25 times the label.

Safety tier
Caution
strict bar
Positive
58%
of 4 reports
Per month
Not priced
Rank
#5
of 86 research peptides

At a glance

Onset
The costochondritis user felt relief within hours of injecting; the MCAS user within the first week.
Lasts
Label courses are 3-10 days, up to four a year; users say the benefit fades within a day or so of stopping.
Access
Grey market
Best effects
Less reaction to food, less malaise and mouth and throat irritation in MCAS (one user, at about 1.6 mg a day) · chest-wall pain gone within hours of an injection in costochondritis (one user) · fewer infections with the oral Thymogen Alpha-1 blend (one confounded user) · claimed: fewer post-operative complications in elderly cancer surgery patients given it intranasally (Russian RCT)
Downsides
Water retention and severe constipation (one user) · weeks of hormonal symptoms ('felt pregnant') at high dose (one user) · benefit stops within a day or so of stopping · nothing at label-like doses for one user · name confusion with thymosin alpha-1, thymalin and thymulin
Typical use
Grey-market vials: 1-2.5 mg subq a day, a dose borrowed from the oglufanide cancer trials. Russian label: 100 mcg IM once a day for 3-10 days (300-1000 mcg a course), up to four courses a year. Oral Thymogen Alpha-1: 1-2 capsules a day (250 mcg each of Thymogen and Vilon), users up to 5.
Stacked with
Stacked with
Thymosin alpha-1: Often compared or alternated with it in MCAS and mould-illness protocols; one user found Thymogen stronger at the same dose. · Vilon: Combined in Integrative Peptides' Thymogen Alpha-1 capsules and in the Holtorf CIRS protocol. · KPV: The oral KPV spray plus Thymogen capsules pairing from Integrative Peptides in CIRS threads.

Safety

Watch
In the 202-patient US phase III trial of intranasal oglufanide (IM862) in AIDS-related Kaposi's sarcoma, time to tumour progression was shorter on the drug (16 vs 35 weeks), though the placebo arm had more patients on antiretrovirals · An immunostimulant: immune and inflammatory flares are plausible, as with thymosin alpha-1 · Grey-market injectable vials: purity, sterility and identity unverified, at doses far above the Russian label
Tier by safety barStrict CautionBalanced CautionEvidence only Caution
  • Seen harm1 of 3
  • Mechanism2 of 3
  • Data gap1 of 3
  • Silent harm1 of 3
  • Product3 of 3
Never if
Hypersensitivity to alpha-glutamyl-tryptophan (label) · Pregnancy or breastfeeding (label: only if the benefit outweighs the risk, for lack of data) · Active autoimmune disease or deliberate immunosuppression · Active cancer, given the faster Kaposi's sarcoma progression in the phase III trial
Why each score
Seen harm 1/3
The Russian label lists only allergic reactions, and the oglufanide cancer trials found mild, transient headache, fatigue and nausea. The one serious signal is confounded: in the 202-patient phase III Kaposi's sarcoma trial, median time to tumour progression was shorter on the drug (16 vs 35 weeks, p=0.012), but the placebo arm had more patients on antiretroviral therapy, which the investigators held responsible for the responses they saw. First-hand reports describe water retention, severe constipation and weeks of hormonal symptoms at a high dose, unpleasant but not serious. Noy et al. 2005: IM862 phase III in AIDS-Kaposi's sarcoma (J Clin Oncol)Thymogen 100 mcg/ml IM solution, Russian SmPC (Cytomed)r/MCAS: Thymogen at about 1.6 mg a day, side effects
Mechanism 2/3
Immune activation is its purpose: the label calls it an immunostimulant (T-cell differentiation, more T-helpers and cytotoxic T cells), and in mice its antitumour effect works through NK-cell activation, so autoimmune or inflammatory flares are credible, as with thymosin alpha-1. It also lowered plasma VEGF in the renal-cancer trial. Thymogen 100 mcg/ml IM solution, Russian SmPC (Cytomed)Smith et al. 2003: NK cells needed for the antitumour activity of L-Glu-L-TrpDeplanque et al. 2004: IM862 phase II in renal cell carcinoma, VEGF fell
Data gap 1/3
Registered in Russia for about 30 years, with thin pharmacovigilance, and its controlled human trials add up to well over a hundred people on the molecule: the 202-patient US phase III (104 on drug), a 44-patient randomised phase II, a 25-patient phase II and a Russian placebo-controlled surgical trial. Noy et al. 2005: IM862 phase III, n=202Tulpule et al. 2000: IM862 randomised phase II, n=44Smirnov et al. 2011: Thymogen before abdominal cancer surgery, double-blind (Russian)
Silent harm 1/3
Immune flares, allergic reactions and the fluid retention and bowel effects users describe appear within days and settle on stopping, though one user's hormonal symptoms took two to three weeks to fade. r/MCAS: side effects took two to three weeks to subside
Product 3/3
Outside Russia, users mostly inject grey-market 20 mg vials sold as Thymogen or Thymagen, at 10-25 times the registered dose, with unverified purity and sterility. Russian pharmacy ampoules (regulated) and the oral Integrative Peptides blend (a supplement) are minority channels. PepGrades: Thymagen 20 mg vial prices across vendorsMendias & Awan 2026 preprint: 6,441 grey-market peptide samples, 42-71% failed quality criteria, 15% had endotoxin

User reports

All 4 reports
Users report
Few reports, from people with mast-cell activation, mould illness or costochondritis, all on other treatments too. An MCAS patient injecting about 1.6 mg a day found it more effective than thymosin alpha-1 (eating without feeling poisoned, less malaise), but it brought water retention, severe constipation and weeks of 'hormonal drama' that made her stop; lower doses did nothing. A costochondritis sufferer says 2.5 mg injected took his chest pain away within hours, though he also calls it thymalin. Two others take Integrative Peptides' oral 'Thymogen Alpha-1' capsules, which also contain Vilon, and credit them with fewer infections or MCAS relief that stops when they stop. Many Reddit mentions of 'Thymogen Alpha-1' are about thymosin alpha-1 instead. Felt nothing: None of 4 first-hand reports; too few to count.
Positive 3Mixed 1
  • r/MCAS

    It is oral and also crazy expensive. And yes, it stops working if I stop or if I have a reoccurring exposure.

    • 2 points
    PositiveOral
  • r/CIRS

    The thymosin/thymogen has helped my immune system too and I don’t get sick as often.

    • 1 point
    Positive3 capsules in the morning, 2 in the afternoonOralabout 4.5-5 months, between injectable courses
  • r/costochondritis

    I just injected myself with 2 1/2 mg of a peptide called thtmagen and I’m noticing my symptoms go away immediately.

    • 0 points
    PositiveRecovery & healing2.5 mg, then 1 mgInjection2-3 days when reported

Studies

Evidence
Approved drug — Registered in Russia since the early 1990s (Cytomed: 100 mcg/ml IM ampoules, nasal spray) as an immunostimulant for infections, wounds and pre-operative preparation, on small Russian studies. As oglufanide (IM862) it went through US and UK cancer trials, including a 202-patient placebo-controlled phase III that found it no better than placebo and well tolerated.
Caveat
The registered dose is 100 mcg once a day for 3-10 days; grey-market users inject 1-2.5 mg, which matches only the doses the US cancer trials gave intranasally. The phase III Kaposi's sarcoma result (faster progression on the drug) is confounded by more antiretroviral use in the placebo arm, and earlier rat work found fewer tumours, so the cancer question is open rather than answered. Users' reports are four, confounded, and in one case possibly about thymalin.
3 more studies and 6 sources

Sources

Similar peptides

Research notes, not medical advice. Updated . Also as Markdown.

Sequence

The peptide's chain of amino acids from its start (the N-terminus) to its end, one bead and one letter for each: A alanine, C cysteine, D aspartic acid, E glutamic acid, F phenylalanine, G glycine, H histidine, I isoleucine, K lysine, L leucine, M methionine, N asparagine, P proline, Q glutamine, R arginine, S serine, T threonine, V valine, W tryptophan, Y tyrosine. A modification such as an N-acetyl cap or a C-terminal amide changes how long it lasts in the body. Length tells related peptides apart, from a two-residue dipeptide like carnosine to a 43-residue protein like thymosin beta-4, and predicts neither effect nor safety.

Report grades

Every first-hand Reddit or X report is graded on its own, from glowing through positive, mixed, nothing and negative to bad reaction, and the bar shows how those grades split. Posts that look vendor-adjacent stay on the peptide's page but are left out of the counts.

GlowingPositiveMixedNothingNegativeBad reaction

% positive

The share of a peptide's graded Reddit and X reports that are glowing or positive, vendor-adjacent posts left out. A peptide with few reports is pulled toward the average of all reports, as if it had eight average ones besides its own, so two glowing posts cannot top the list. Peptides rank by this figure, those with no graded report yet after those with one, and Avoid ones after every other entry.

Researcher estimate

No first-hand report of this peptide has been graded yet, so the figure is the researchers' own rating out of 10 from what they read about it. It ranks after every peptide with graded reports until its own arrive.

Safety tier

Each peptide is tiered Clean, Caution or Avoid from its five risk axes under the chosen safety bar. An Avoid peptide carries a real risk of harm, a plausible route to serious harm rather than mere unpleasantness, so it stays listed with the reason but ranks behind every other entry, however good its reviews.

Safety bar

The safety bar sets how much risk it takes to rate a peptide Avoid. Strict: out on any serious mechanism with little human data, or any documented serious harm. Balanced: out on documented serious harm (unless it is obvious, reversible and from a regulated product), or a serious mechanism whose harm would be silent with no human data at all. Evidence only: out only on documented serious harm in humans that is lasting, delayed or from grey-market product.

Seen harm

Documented serious adverse events in humans, from 0 for none despite real exposure to 3 for deaths or several well-documented serious harms. Serious means a hospital or emergency visit or harm lasting weeks, so a headache or a bad night does not count.

Mechanism

A plausible biological route to serious harm at the doses people use, such as growth-factor signalling, hormone-axis suppression, heart or blood-pressure effects or immune activation. It runs from 0 when none is known to 3 when a dangerous pathway has been shown in living animals.

Data gap

How little human safety data exists for the molecule actually sold, from 0 for an approved drug with large trials and years of use to 3 for no human safety data at all. A modified analogue does not inherit its parent's trials.

Silent harm

Whether the feared harm would show quickly or stay hidden, from 0 when it is obvious and goes on stopping to 3 when it is silent and delayed, like tumour promotion or slow organ damage. User reports cannot reveal a harm that takes years to appear, so a high score here limits what good reviews can tell you.

Product

The risk of what people actually buy, from 0 for a regulated pharmacy or supplement product taken by mouth or on the skin to 3 for a grey-market injectable. In one dataset of 6,441 grey-market samples, 42–71% failed basic quality criteria and 15% carried endotoxin; taken by mouth or in the nose, a pack avoids the injection risks.

Evidence

The strongest kind of study behind the peptide's effects, from an approved drug through human controlled trials and small human studies to animal work or nothing of its own. Animal results often fail to carry over to people.

Access

How people get it: as an approved drug, a compounded prescription, an over-the-counter supplement or from the grey market, where nobody checks the vial. The channel decides both the legal position and the risk of a bad batch.

Price per month

Thirty days of the typical dose, from its low end to its high end, priced at the listing a careful buyer would choose: in stock, from a shop scoring 4 of 5 on trust (third-party tested where no score is set), failing that 3, a pure pack before a blend, a European shop first, then the cheapest per mg. The range is the dose's, not the shops'. A per-dose amount counts once a day unless the dose says otherwise. The shop table keeps each listing's price per mg, per gram for bulk supplements. Where no listing can be priced the researchers' own estimate stands in, and says so.

Dose users report

The middle half of the daily doses stated in at least five first-hand reports, vendor posts left out. Where its middle sits more than twice above or below the declared dose, the month is priced at it as well, since what people take is what they pay for.

Shop trust

Each shop's trust on a 1–5 scale, read from its testing and its reputation: 1 for serious red flags (fabricated COAs, scam reports, impersonation, a closed shop), 2 for no public testing, a new shop or active complaints such as seized parcels, 3 for its own COAs or a short track record, 4 for verified third-party testing or a strong reputation, and 5 for third-party batch reports that name the shop, with years of good independent reputation. A shop without a score counts third-party batch testing as 4, its own COAs as 3 and no public tests as 2.

Best value

Within a category or a goal, a peptide that no other beats on both counts: none is rated more positively for the same or a lower monthly price, and none costs less for the same or a higher rating. The chart joins these into the best-value line; the cheapest of them and the best-rated of them both make it, so the line spans the trade-off from cheap to best. Avoid entries never count, and a peptide needs both a % positive and a price to be compared.

Testing

Whether the shop publishes lab results: third-party tested means an independent lab checks each batch, own COA means the shop's own certificate of analysis, and no public tests means neither. A certificate shows purity, not safety.

Added peptide

Some packs sold under one peptide's name hold a second one, such as 5 mg GHK-Cu in a nasal kit, stated only in the description. Sprayed in the nose or injected it reaches the blood like an injection, so it carries the risk of that route and is tiered as the injectable form, whatever its tier on the skin. A pack whose page gives no contents list may hold more than its name.