Compare prices and buy Thymogen from 3 research peptide vendors - also called suppliers or sources. Updated daily.
A synthetic dipeptide (L-glutamyl-L-tryptophan, CAS 38101-59-6) with the international nonproprietary name oglufanide, whose disodium salt carries the development code IM862. It was isolated as one of the active components of the calf thymus extract Thymalin, and its developers report that it acts on T-cell differentiation. Registered in Russia as injectable, nasal spray and topical cream products, and not FDA-approved.
For research purposes only. Not medical advice.
Thymogen is the dipeptide L-glutamyl-L-tryptophan, written Glu-Trp or EW, and is catalogued in Immune & Anti-inflammatory. FDA's substance registry, GSRS, files the free acid under its international nonproprietary name, oglufanide (UNII 4RHY598T5U, formula C16H19N3O5), and its disodium salt as a separate substance, oglufanide disodium (UNII Q60AU1LLNU, CAS 237068-57-4), which carries the development code IM862. The dipeptide came out of work on the calf thymus extract Thymalin, whose page covers that history.
The Phase 3 report below calls IM862 a synthetic dipeptide with antiangiogenic properties in vitro and in vivo, and GSRS records it as an inhibitor of vascular endothelial growth factor A and basic fibroblast growth factor. In the Oxford trial below, plasma VEGF fell significantly during treatment.
A 2024 review in the International Journal of Molecular Sciences, by Russian researchers who describe the Glu-Trp work as their own, calls Thymogen an immunostimulant. It reports that in experimental studies the dipeptide restored T-lymphocyte numbers in lymphoid organs and regulated stem and colony-forming cells. The same review summarizes Russian clinical use in patients receiving chemotherapy for lymphoproliferative tumors, reporting faster recovery of white-cell counts between courses.
The record outside Russia is in cancer, mostly AIDS-related Kaposi's sarcoma, a tumor of endothelial-cell origin.
A randomized study at the University of Southern California, published in the Journal of Clinical Oncology in 2000, compared two schedules of an IM862 nasal solution in 44 patients with AIDS-related Kaposi's sarcoma and had no placebo arm. Major responses were reported in 16 of the 44 (36 percent).
The Phase 3 trial that followed, published in the same journal in 2005 by the AIDS Malignancy Consortium and an IM862 study team and supported by National Cancer Institute grants, randomized 202 HIV-positive patients to IM862 or placebo under double-blind conditions for 24 weeks. The abstract, which does not state the analysis population, reports responses in 23 percent of the IM862 group and 21 percent of the placebo group, and a shorter median time to progression with IM862, 16 weeks against 35. The authors concluded IM862 was not superior to placebo and may accelerate progression, and that antiretroviral therapy alone produced sustained tumor responses that may have contributed to earlier estimates of IM862's effect. ClinicalTrials.gov's Phase 3, double-blind IM862 record in this disease (NCT00002445) lists Cytran as lead sponsor and posts no results.
A Phase II trial at the Cancer Research UK Medical Oncology Unit in Oxford, published in the British Journal of Cancer in 2004, enrolled 25 patients with metastatic renal cell carcinoma. None had an objective response, 8 had stable disease and 17 progressed on treatment. The authors concluded IM862 should not be evaluated further as a single agent at the dose and schedule tested.
ClinicalTrials.gov lists three more IM862 studies, none with posted results:
In Russia, Thymogen is a registered medicine. The 2024 review gives its Ministry of Health registration certificate as P N002408/01, dated June 10, 2009.
In the United States it holds no approval. It received two orphan drug designations, which are development incentives and not approvals: for AIDS-related Kaposi's sarcoma in 1999, and as oglufanide disodium for ovarian cancer in 2001. FDA's orphan database lists both as designated, with Implicit Bioscience of Brisbane as the last reported sponsor.
An FDA warning letter dated December 8, 2025 to Darmerica, LLC, a Florida distributor of drug ingredients to compounding pharmacies, named thymogen among the ingredients it distributed that are ineligible for use in human drug compounding under section 503A.
A check on October 21, 2026 found it under none of the names Thymogen, Thymagen, oglufanide or IM862 in:
Vendor titles use Thymogen, and as of October 21, 2026 one indexed vendor titled its product with the spelling Thymagen. PubChem also lists the transliteration Timogen. The product pages readable that day gave CAS 38101-59-6, the free acid's formula C16H19N3O5 and the name oglufanide, and neither stated a salt form.
They name one dipeptide in different forms. Thymogen is the Russian trade name for L-glutamyl-L-tryptophan, CAS 38101-59-6, and oglufanide is that molecule's international nonproprietary name. IM862 is the development code of its disodium salt, which FDA's substance registry lists as oglufanide disodium with a separate CAS number, 237068-57-4. ClinicalTrials.gov's US trial records name the drug as IM862 or oglufanide disodium. Thymagen is an alternative spelling one vendor uses in its product title.
Its authors reported that IM862 was not superior to placebo. The trial, published in the Journal of Clinical Oncology in 2005 by the AIDS Malignancy Consortium and an IM862 study team, randomized 202 HIV-positive patients with AIDS-related Kaposi's sarcoma to IM862 or placebo under double-blind conditions for 24 weeks. The abstract, which does not state the analysis population, reports tumor responses in 23 percent of the IM862 group and 21 percent of the placebo group, and a shorter median time to progression with IM862, 16 weeks against 35. The authors concluded that antiretroviral therapy alone produced sustained tumor responses that may have contributed to earlier estimates of IM862's effect.
Not under section 503A, according to FDA. A warning letter FDA issued on December 8, 2025 to a company distributing drug ingredients to compounding pharmacies named thymogen among the ingredients that are ineligible for use in human drug compounding under section 503A. As of October 21, 2026 the compound had no application in FDA's drugsfda database and did not appear on FDA's 503A or 503B bulk drug substance nomination lists. Its two US orphan drug designations, received in 1999 and 2001, are development incentives and not approvals.
They are built from the same two amino acids but are different molecules with opposite reported effects. Thymogen is L-glutamyl-L-tryptophan, which a 2024 review by Russian researchers describes as an immunostimulant. Thymodepressin, another Russian drug, is the disodium salt of gamma-D-glutamyl-D-tryptophan. It uses the mirror-image D forms of both amino acids, links them through the side chain of glutamic acid, and the same review describes it as an immunosuppressant. The CAS number 38101-59-6 identifies Thymogen's L form.
Thymogen is sold by 3 research peptide vendors indexed on PeptideScouter, with 3 tracked listings compared per vendor in the table above. Pricing is normalized and refreshed daily.
2 of the 3 indexed vendors currently have Thymogen in stock. The comparison table marks out-of-stock listings, and stock state is refreshed daily.
Platinum Lion Peptides currently lists Thymogen at $3.25/mg, the lowest listed price across 3 tracked research peptide vendors. With current vendor discount codes applied, the lowest effective price is $2.92/mg.
Discount codes are issued per vendor rather than per peptide, so any code applies across that vendor's whole catalog. All 3 vendors listing Thymogen publish a PeptideScouter code, worth 10% off. Applied, the lowest effective price falls from $3.25/mg listed to $2.92/mg at Platinum Lion Peptides. Each vendor's code is shown beside its price in the table above.
Thymogen ranges from $3.25/mg to $5.40/mg across 3 listings from 3 research peptide vendors, normalized to USD per milligram and refreshed daily.
3 research peptide vendors currently list Thymogen on PeptideScouter, with 2 in stock right now. We track 3 listings across size and kit variants.
Thymogen's CAS Registry Number is 38101-59-6. It is also sold as Thymagen.
