Thymogen Peptide: Benefits, Trial Results and Safety

Research use only. Nothing on this page is medical advice, and Thymogen isn’t approved for use in the US or EU.

Thymogen is the dipeptide Glu-Trp, two amino acids long. Sold as IM862, it failed a 202-patient placebo-controlled phase III trial in Kaposi’s sarcoma (1). What the evidence shows:

• Cancer trials: no benefit in Kaposi’s sarcoma (1) and no responses in kidney cancer (2)
• Small Russian trials: better immune markers, fewer surgical complications and gastric repair (3, 4, 5)
• Most of this evidence exists only as abstracts, and none of it tested a vial bought from a research seller

Jump to the studies, safety or where to buy.

Sequence

L-Glu-L-Trp (EW), a dipeptide first isolated from the calf thymus extract Thymalin (6)

Also called

Oglufanide, IM862, alpha-glutamyl-tryptophan (2, 7)

Formula

C16H19N3O5, 333.34 g/mol, CAS 38101-59-6 (7)

Human reports

8 found: 3 as IM862, 5 Russian. Two cancer trials found no benefit (1, 2)

Largest trial

202 people with Kaposi’s sarcoma: 23% responded on IM862, 21% on placebo (1)

Russia

Registered drug, certificate P N002408/01, 10 June 2009 (6)

FDA status

Not approved. Not on FDA’s compounding-risk page or in HHS’s October 2026 interim policy (8, 9)

WADA 2026

Not named. S0 may not apply because Russia registered it (10)

What is Thymogen peptide?

Thymogen is a synthetic dipeptide of L-glutamic acid and L-tryptophan. Researchers isolated it from Thymalin, a calf thymus extract, then made it synthetically (6). Oglufanide and IM862 are names for the same L-Glu-L-Trp dipeptide, which is why the Western trials don’t appear when you search for Thymogen (2, 7).

Four similar names get mixed up on product pages.

Thymogen studies, sorted by closeness to humans

Fourteen sources are below. Eight are human reports, three of them double-blind and placebo-controlled. Every Russian report is an abstract with few numbers.

The human results split by condition. The two cancer trials found nothing. The Russian trials measured immune markers, surgical complications and a stomach biopsy, and none is available with full numbers. Three trials were double-blind and placebo-controlled: Kaposi’s sarcoma (negative), pre-surgery in elderly cancer patients (positive) and atrophic gastritis (positive on one biopsy measure).

Did Thymogen work in the IM862 trials?

No. In the 2005 phase III trial, 23% of 104 people on IM862 responded against 21% of 98 on placebo, and the drug group progressed sooner, at 16 weeks against 35 (1). The authors wrote that antiretroviral therapy, which was improving at the time, may have inflated the earlier 36% response rate (1).

The kidney cancer trial was also negative. Of 25 people, 17 progressed and none had an objective response, although blood VEGF fell, which the authors thought justified more work (2).

A failed cancer trial says little about an immune marker or a gastric biopsy, so the Russian reports aren’t wrong because of it. It does mean no clinical benefit has been confirmed in a large trial with full results.

What does Thymogen do in cells?

In THP-1 leukemia cells and donor blood cells, Thymogen raised the activity of genes for innate immune sensors, and the cells released TNF-alpha and IL-1beta (16). A second study of five Khavinson peptides found a calmer picture: after a bacterial trigger, differentiated THP-1 cells made less TNF and IL-6 (17). The two used different conditions, so they don’t strictly conflict, but they show the effect depends on the setup.

A computer model predicts a fit to a T-cell receptor (18), and the developers’ review proposes that the peptide opens condensed chromatin in lymphocytes (6). Neither is a measured result in a living system. Tissues also carry dipeptidases that cut dipeptides into amino acids (6), so what a dose does after absorption is still an open question.

Thymogen vs Thymodepressin: the mirror image

Flip both amino acids to the D form and you get Thymodepressin. In mouse bone marrow, all-L Glu-Trp did not change progenitor growth in intact marrow, while the D forms suppressed it (15). Thymodepressin is registered in Russia as an immunosuppressor (6).

Both share the formula C16H19N3O5 and a mass of 333.34 g/mol (7). A mass spectrum or a purity percentage can’t separate them, which is why a certificate needs more than “99%”.

Thymogen dosage: is there one?

No dose is established for the powder research sellers offer. Most human reports gave a pharmaceutical nasal product (3, 4), and the tuberculosis report used injections (13). A vial label shows how much material it holds, which isn’t a dose. We don’t give schedules here, and a number from a forum or seller page can’t be traced to these studies without a source.

Thymogen side effects and safety

Low toxicity is the most repeatable finding. The kidney cancer trial recorded no drug-related grade 2 or 3 toxicity (2), and the authors of the 20-volunteer nasal spray study called a 10-day course safe (4).

Two limits apply. In Kaposi’s sarcoma the drug group progressed sooner than placebo, so “well tolerated” doesn’t mean harmless (1). And every safety follow-up here is short. We found no study in people with autoimmune disease or in pregnancy, and none on long-term use.

Is Thymogen approved or legal?

Russia’s health ministry registered Thymogen under certificate P N002408/01 on 10 June 2009 (6). We found no FDA or EU approval. It isn’t on FDA’s compounding-risk page or in the HHS interim policy of 28 October 2026, which covers six other peptides (8, 9). Vials sold online are labeled research-use-only, a sales category that says nothing about contents.

WADA’s 2026 list doesn’t name Thymogen. Its S0 class covers substances with no approval from any government health authority, and Russia has registered this one, so S0 may not apply. A tested athlete should ask their anti-doping organization first (10).

Is the vial the same Thymogen the studies used?

Often nobody knows. The trials used a sponsor’s IM862 or a Russian pharmaceutical product, and a research vial is only as good as its lab report. Because Thymodepressin and the gamma-bonded isomers share Thymogen’s formula and mass, identity matters more than purity here (7, 15).

Our guide to verifying a peptide COA explains each line, and best peptide vendors compares sellers by what their lab reports show.

Where to buy Thymogen

SwissChems lists a 20 mg Thymogen vial. The listing gives the same formula, mass and CAS number as PubChem, and states a lab report per batch (7, 19). It doesn’t mention chiral testing, so ask for it before you rely on the vial.

Keep researching: the Khavinson peptides guide, Vilon, thymulin, Epitalon, the full list of peptides and bioregulator capsules.

Thymogen FAQ

Sources