Thymalin

Dosing from the Literature

Published for immunity: 5–20 mg a day by intramuscular injection for 3–10 days, repeated after 1–6 months if needed, in the Russian product instructions; 10 mg per injection in the trials below. Not published: a Western randomized trial.

Thymalin is supplied in Russia as a lyophilized powder, 10 mg per vial, dissolved in 0.9% sodium chloride for intramuscular injection (Russian product instructions). The rows below give the doses in those instructions and in the trials cited on this page. Thymalin is not legally compounded by U.S. compounding pharmacies.

What It Is

Thymalin (Russian: Тималин; transliterated also as "Timalin") is a parenteral polypeptide preparation manufactured from the thymus glands of calves by controlled mild acid extraction followed by acetone fractionation. The end product is a lyophilized white-to-cream powder of low-molecular-weight peptides with molecular weights below approximately 10 kilodaltons. It is not a single defined-structure peptide; it is a complex polypeptide fraction whose biological activity reflects the combined contribution of many short peptide species released by gland processing. In regulatory terms it sits in the same category as Cerebrolysin — a biological extract rather than a synthetic single-molecule pharmaceutical.

The drug was developed in the 1970s at the Military Medical Academy named after S.M. Kirov in Leningrad (now St. Petersburg) by V.G. Morozov and V.Kh. Khavinson, originally under a Soviet Ministry of Defense commission to develop interventions for soldiers exposed to radiation, chemical injury, and severe trauma. The development line subsequently moved with Khavinson to the St. Petersburg Institute of Bioregulation and Gerontology, where the broader family of "peptide bioregulators" (Thymalin, Epithalamin, Cortexin, Prostatilen, Retinalamin, Vladonix, and others) was elaborated over the following decades. Thymalin received Russian Ministry of Health registration as an immunomodulating drug in 1982 and has remained in continuous clinical use since.

Thymalin is not the same compound as several other "thymic" peptides commonly mentioned in the same conversation, and these distinctions matter:

• Thymosin alpha-1 (Tα1) — A defined-structure synthetic 28-amino-acid peptide originally isolated from bovine Thymosin Fraction 5; marketed internationally as Zadaxin (thymalfasin). It is a single, fully characterized molecule with FDA orphan-drug status and broad ex-US approvals. Mechanistically overlapping (T-cell maturation, NK restoration), but pharmacologically and regulatorily distinct.
• Thymopentin (TP-5) — A synthetic pentapeptide (Arg-Lys-Asp-Val-Tyr) corresponding to active residues 32–36 of thymopoietin. Defined structure, distinct compound, distinct development lineage.
• Thymogen — A synthetic dipeptide (L-Glu-L-Trp) that the Khavinson group isolated from Thymalin by reversed-phase HPLC and subsequently synthesized as a single defined-structure molecule. Thymogen is therefore a "child" of Thymalin in the bioregulator family — a synthetic short peptide derived from one of Thymalin's active components — but it is itself a different drug, regulatorily and pharmaceutically separable.
• Vilon (Lys-Glu), Bestim, and other Khavinson-family thymic short peptides — Defined-structure synthetic di- and tripeptides developed in the same lineage. Different molecules.

The Khavinson group's working theoretical frame is that Thymalin's biological activity is dominated by a small number of short peptide motifs released within the complex — particularly the dipeptides Glu-Trp (EW) and Lys-Glu (KE) and the tripeptide (a chain of 3 amino acids) Glu-Asp-Pro (EDP) — which the group hypothesizes can penetrate cell and nuclear membranes and modulate gene expression by direct interaction with promoter-region DNA and with histone proteins. This "short peptide DNA-binding" hypothesis is the central mechanistic claim of the Khavinson research school and is articulated across reviews including Khavinson & Popovich (2017) and the systematic peptide-regulation reviews indexed in PubMed (PMID 27909961; PMID 31808038).

Who Khavinson was, and what his record supports →

Mechanism of Action

The mechanistic work cited here comes from the Khavinson group and its collaborators: Khavinson is an author on all 19 papers and chapters in the reference list, published from 1982 to 2022. The principal claims, with the findings behind them:

• T-cell maturation enhancement — Thymalin activated T-cell differentiation, its developers reported (Morozov & Khavinson 1997, PMID 9637345). The group describes its effect as normalization rather than blanket stimulation: in its 2003 elderly study, Thymalin returned immune measures that were abnormal at baseline, such as NK-cell counts and phagocytosis, to normal (Khavinson & Morozov 2003, PMID 14523363). It was approved in the USSR in 1982 as an immunomodulator (Khavinson & Morozov 2003); its current Russian product instructions class it as an immunostimulant.
• CD4/CD8 ratio — In 42 adults hospitalized with COVID-19 pneumonia, the CD4/CD8 ratio rose 1.7-fold after a 5-day Thymalin course, against before treatment (Khavinson et al. 2021, PMID 33575961); in older patients with severe COVID-19, it did not change significantly (Kuznik et al. 2021). The 2003 elderly study measured the ratio but does not report a result for it (Khavinson & Morozov 2003, PMID 14523363).
• NK cell counts — Elderly women in the 2003 study started with low NK-cell (CD56+) levels, which Thymalin normalized (Khavinson & Morozov 2003, PMID 14523363); in older patients with severe COVID-19, NK-cell counts rose 2.4-fold with Thymalin and did not change significantly with standard treatment alone (Kuznik et al. 2021). Neither study measured NK-cell killing activity.
• IL-2 and interferon release — Thymalin and the synthetic dipeptides Thymogen and Vilon changed the IL-2 and interferon released by blood lymphocytes, the developers reported (Morozov & Khavinson 1997, PMID 9637345).
• Hypothalamic-pituitary-thymus axis modulation — In the group's 2003 study, Thymalin alone lowered raised cortisol in the Kiev arm, and given with Epithalamin it normalized ACTH, TSH and insulin in St. Petersburg; the authors tie this to closely interacting neuroendocrine and immune systems (Khavinson & Morozov 2003).
• Pineal-thymus crosstalk — In the group's 2003 randomized study in elderly people, groups were given Thymalin, the pineal (small brain gland that makes melatonin) extract Epithalamin, both, or placebo, and mortality fell most in the groups given both (Khavinson & Morozov 2003, PMID 14523363).
• Hematopoietic stem cell differentiation — Khavinson and Linkova (Bull Exp Biol Med 2020, PMID 33237528) reported that Thymalin activates differentiation of human hematopoietic stem cells toward the lymphoid lineage in vitro, providing a candidate mechanism for the drug's reported activity in radiation- and chemotherapy-induced hematopoietic depression.
• Anti-inflammatory cytokine modulation — Avolio et al. (PMID 35408963) found in the human THP-1 monocyte/macrophage cell line that Thymalin, like Epitalon, Vilon, Thymogen and Chonluten, reduced LPS-induced release of TNF-α (a major inflammatory signaling molecule) and IL-6 (a pro-inflammatory cytokine tied to chronic inflammation); unlike the four short peptides, it increased the cells' adhesion to LPS-activated endothelium (HUVEC). The authors suggest the Khavinson peptides act as inducers of TNF tolerance in monocytes and as anti-inflammatory molecules on macrophages.
• Hemostatic system normalization — In rats, Thymalin lowered platelet aggregation, and in rats whose thymus had been removed it normalized platelet measures (Kuznik et al. 1986, PMID 3754821). In older people in Kiev it increased fibrinolysis and reduced signs of hypercoagulation (Khavinson & Morozov 2003), and in adults hospitalized with COVID-19, D-dimer fell 5.7-fold with Thymalin added to standard treatment against 2.1-fold with standard treatment alone (Khavinson et al. 2021, PMID 33575961), part of the group's rationale for using it in COVID-19.
• Khavinson short-peptide DNA-binding hypothesis — The Khavinson group proposes that Thymalin's activity comes from short peptides in it (Glu-Trp / EW, Lys-Glu / KE and Glu-Asp-Pro / EDP), which it says enter the cell nucleus and bind DNA or histone proteins, changing gene expression (Kuznik et al. 2021; Khavinson et al. 2021, PMID 33575961). The group's 2016 test of DNA binding was a computer docking model (Khavinson et al. 2016, PMID 27909961), and Khavinson is an author on every paper cited on this page.
• Multi-component, multi-target profile — Thymalin is a complex of many peptides rather than one molecule, and its developers write that the targeted molecular mechanism of its activity "requires further study" (Khavinson et al. 2020, PMID 33237528).

What the Research Shows

Thymalin's research base spans more than four decades and several thousand Russian-language publications, with a smaller subset of English-language peer-reviewed reports. The signal is consistent across applications, but the evidence quality is uneven and heavily concentrated in one research school.

• Immunosenescence in the elderly — The most-cited human dataset is the Khavinson & Morozov 6–8-year geroprotective study in 266 elderly persons (PMID 14523363, PMID 12577695). Repeated short courses of Thymalin (with or without Epithalamin) were associated with normalization of immune (NK cells, phagocytosis), endocrine (ACTH, TSH, insulin), and metabolic parameters; with reduced incidence of acute respiratory infection (2.0–2.4-fold), ischemic heart disease manifestations, hypertension, and osteoarthrosis; and with mortality reductions of 2.0–2.1-fold (Thymalin alone), 1.6–1.8-fold (Epithalamin alone), and 2.5-fold (combination) versus placebo controls — with a sub-cohort treated annually with the combination for six years showing a 4.1-fold mortality reduction.
• Post-viral and post-infectious immune restoration — Russian clinical reports describe Thymalin courses for patients recovering from viral pneumonia, herpes-virus reactivation, and bacterial infections complicated by immunosuppression. Reported effects include lymphocyte subset normalization, faster clinical recovery, and reduced relapse frequency. Most of these reports predate modern reporting standards; they are historical evidence rather than confirmatory RCTs.
• Pulmonary disease adjunct — Lukyanov et al. (International Journal of Immunology and Immunotherapy 2020) reported on Thymalin in severe SARS-CoV-2 pneumonia, with an early case showing rapid clinical improvement and reduced oxygen requirement following the addition of Thymalin to standard care. The 2021 Khavinson group review (Biol Bull Rev; PMC8365293) summarizes Thymalin's reported activity in pulmonary infection, lung abscess, and pneumonia recovery.
• COVID-19 — severe-cohort trial — Kuznik, Khavinson, Shapovalov et al. ("Peptide Drug Thymalin Regulates Immune Status in Severe COVID-19 Older Patients", Adv Gerontol 2021) reported on older patients with severe COVID-19 enrolled at the Affiliated Hospital of Chita State Medical Academy under IRB approval (protocol no. 102, 15 May 2020). The Thymalin arm showed accelerated reversal of lymphopenia, recovery of platelet/lymphocyte ratio, and recovery of CD3+HLA-DR+, CD4+, B-, and NK-cell subpopulations relative to standard care, with reported reduction of in-hospital mortality.
• Adaptive immunity and antibody response — Khavinson, Kuznik, Volchkov et al. ("Effect of thymalin on adaptive immunity in complex therapy for patients with COVID-19", Klinicheskaya Meditsina 2020, vol 98, no 8, pp 593–599) reported comparative IgG-to-SARS-CoV-2 dynamics in patients receiving Thymalin alongside standard care vs standard care alone, suggesting an effect on the adaptive antibody response.
• Geroprotection and longevity — Aside from the 266-patient elderly cohort, Khavinson-group publications also report carcinogenesis attenuation in C3H/Sn mice with low-MW thymic, pineal, and hypothalamic (brain's hormonal control center) peptide factors (Anisimov, Khavinson, Morozov; Mech Ageing Dev 1982), supporting the broader "peptide bioregulator" geroprotection narrative.
• Mechanistic in vitro work — Avolio et al. (PMID 35408963) provides an Italian-collaboration human-cell mechanistic study of Thymalin and four other Khavinson peptides in the THP-1 monocyte/macrophage line, finding that all five reduced LPS-induced TNF and IL-6 release; the four short peptides reduced the cells' adhesion to activated endothelium, while Thymalin increased it. The lab work was done in Italy, with St. Petersburg co-authors including Khavinson.
• Thymalin and stem cell differentiation — Khavinson, Linkova et al. (Bull Exp Biol Med 2020, PMID 33237528) reported that Thymalin activates differentiation of human hematopoietic stem cells, supporting the proposed mechanism for hematopoietic-recovery applications.
• Hemostatic effects — Older Russian work (Kuznik, Makhakova, Morozov, Pisarevskaya, Khavinson, PMID 3754821) characterized Thymalin's effect on platelet aggregation in intact and thymectomized rats, an early piece of the "thymus-hemostasis axis" literature the Khavinson group continues to develop.
• Inflammatory disease adjunct — Russian reports describe adjunctive Thymalin in inflammatory pulmonary, gastrointestinal, and dermatologic disorders. These reports are heterogeneous in design: early-phase clinical signal rather than confirmatory data.

Human Data

Thymalin's human evidence base is unusually large by total cumulative person-years (forty-plus years of post-marketing exposure in Russia and the post-Soviet space), but unusually narrow by sociology of authorship. The most clinically informative published reports:

• Khavinson & Morozov 2003 (PMID 14523363) — 266 elderly (60+) subjects across St. Petersburg and Kiev gerontology centers: four groups in St. Petersburg (placebo, Thymalin, Epithalamin, or Thymalin + Epithalamin combination) and three in Kiev (no combination arm), split by what the paper calls “stratification randomization”, with no further detail on how. Bioregulators were given intramuscularly, in St. Petersburg 10 mg a day for 10 days (100 mg per course) in 1996 and again in 1997, in Kiev five 10 mg doses 2–3 days apart (50 mg per course), six courses over 3 years; subjects were followed for 6–8 years. Outcomes included improvement in cardiovascular, endocrine, immune, and nervous system indices; reduction in age-associated disease incidence; and mortality reductions of 2.0-fold (Thymalin alone) and 4.1-fold (combination, six annual courses) vs placebo controls.
• Khavinson & Morozov 2002 — Adv Gerontol (PMID 12577695) — Russian-language companion publication of the geroprotective trial.
• Khavinson, Kuznik, Ryzhak 2013 (PMID 24003726) — Russian-language Adv Gerontol review summarizing long-term clinical results across the bioregulator family (Timalin, Thymogen, Vilon, Epithalamin, Prostatilen, Cortexin, Retinalamin) for prevention of age-related disease.
• Kuznik, Khavinson, Shapovalov et al. 2021 — severe COVID-19, Adv Gerontol — Single-center (Affiliated Hospital of Chita State Medical Academy) trial in older patients with severe COVID-19. Thymalin was added to standard care; the Thymalin arm showed faster reversal of lymphopenia, restoration of CD3+HLA-DR+, CD4+, B- and NK-cell subpopulations, recovery of platelet/lymphocyte ratio, and reduced in-hospital mortality vs standard care alone. IRB-approved protocol no. 102, 15 May 2020.
• Khavinson, Kuznik, Volchkov et al. 2020 — Klinicheskaya Meditsina — Effect of Thymalin on adaptive immunity in COVID-19 complex therapy; reports comparative IgG-to-SARS-CoV-2 dynamics with vs without Thymalin.
• Lukyanov, Kuznik, Shapovalov, Khavinson et al. 2020 — Int J Immunol Immunother 7:055 — Severe COVID-19 case treated with Thymalin 10 mg IM daily after failed standard care, with marked early clinical improvement.
• Khavinson, Kuznik, Tarnovskaya, Linkova 2021 — Stem Cell Rev Rep (PMID 33575961) — Open-label randomized trial at a St. Petersburg city hospital in 2020: 92 adults with COVID-19 pneumonia and low lymphocyte counts, 42 of them also given Thymalin 10 mg IM daily for 5 days. With Thymalin, lymphocyte, T-cell and CD4 counts rose and IL-6, C-reactive protein and D-dimer fell more than with standard treatment alone; no one died in either group.
• Khavinson, Linkova et al. 2020 — Bull Exp Biol Med (PMID 33237528) — Demonstrates Thymalin activation of human hematopoietic stem cell differentiation, providing in vitro mechanistic support for clinical observations in immunorehabilitation.
• Khavinson, Linkova, Chalisova, Ivko 2021 — Biology Bulletin Reviews (PMC8365293) — "The Use of Thymalin for Immunocorrection and Molecular Aspects of Biological Activity" — narrative review of Thymalin's reported uses (viral and bacterial infections, lung abscess, immune and blood-cell suppression after chemotherapy or radiation, geroprotection) and of its short peptides EW, KE and EDP.
• Khavinson 2002 — Neuro Endocrinol Lett (PMID 12374906) — "Peptides and Ageing" — narrative review noting that among Thymalin's effects, immune-stimulating activity is the most prominent.

Cumulative cohort experience implied by Russian post-marketing data runs into hundreds of thousands of patient-courses across the 1982–2026 period, but no large independent western RCT confirms the headline outcomes. The human dataset is long, deep, and consistent within a single research school and regulatory jurisdiction, and thin and largely absent outside it.

Reconstitution & Storage

The Russian product instructions describe a lyophilized white or yellowish-white powder, 10 mg per vial, dissolved in 1–2 mL of 0.9% sodium chloride immediately before the injection. The table is arithmetic for the 10 mg vial.

• Reconstituted solution — The Russian product instructions describe it as clear and colorless or yellowish.
• Storage — lyophilized — The Russian product instructions list storage protected from light at no more than 25 °C, and a shelf life of 3 years.
• Storage — reconstituted — The Russian product instructions say the solution is made immediately before the injection and is not to be stored.
• Research-supplier material — Products sold as Thymalin by research suppliers are not the registered Russian drug and may not match its specification. As a mixture of peptides under 10 kDa rather than one molecule (Khavinson & Morozov, 2003), Thymalin has no single molecular mass for a lab report to match.

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Side Effects & Risks

Thymalin's developers wrote in 2003 that 25 years of trials and use had shown no allergic or other side effects (Khavinson & Morozov, 2003); the current Russian product instructions list allergic reactions as its one side effect and contraindicate it in hypersensitivity, pregnancy and breastfeeding. Risks worth noting:

• Hypersensitivity reactions — Allergic reactions are the one side effect the Russian product instructions list, with no frequency given. They contraindicate Thymalin in people hypersensitive to it or to its excipient (glycine) and call for caution in people with a history of allergy.
• Theoretical autoimmune risk — The Russian product instructions class Thymalin as an immunostimulant, so in theory it could worsen autoimmune disease; they do not list autoimmune disease among its contraindications.
• Pregnancy and lactation — The Russian product instructions list pregnancy and breastfeeding as contraindications.
• Pediatric use — The Russian product instructions cover children from 6 months to 14 years with immune deficiency, at age-based daily doses from 1 mg (under 1 year) to 3–5 mg (7–14 years) for 3–10 days.
• Source / purity concerns (research supply) — Thymalin is an extract of calf thymus (Russian product instructions). Products sold as Thymalin by research suppliers are research chemicals, not the registered Russian drug, so neither their contents nor their source animals can be assumed to match it.
• Bovine source — TSE / prion-safety considerations — As a cattle-tissue extract, Thymalin carries a theoretical risk of prion or other infectious contamination. Its developers acknowledge the risk and state that their extraction degrades large proteins and that their tests found no prions or viruses (Khavinson & Morozov, 2003); the Russian product instructions specify thymus glands from calves and young cattle under one year old. Research-chemical material comes with no such assurance.
• Drug interactions — The Russian product instructions say Thymalin may act synergistically with some pituitary hormones (somatotropin, luteinizing hormone) and with estrogens, and opposes the effects of progestins, androgens and adrenal hormones on the lymphatic system and bone marrow. They call it compatible with isoniazid, rifampicin, glucocorticoids, immunostimulants and painkillers, and advise against combining it with drugs that act the same way.
• Long-term safety — No study of long-term safety was found; the Russian product instructions give short courses (3–10 days, repeated after 1–6 months if needed).
• WADA caution — Thymalin is not specifically named on the current WADA Prohibited List, but a thymic polypeptide complex with claimed effects on hematopoietic stem cell differentiation, T-cell maturation, and immune function could plausibly be evaluated under broader category language.
• No western safety review — Thymalin is not approved in the US or EU, so no FDA or EMA review of its safety exists; what is known about its side effects comes from its Russian product instructions and the Khavinson group's reports.

Bloodwork & Monitoring

No label or guideline that sets monitoring for Thymalin was found; its Russian product instructions list none. In the trials, the researchers measured immune cell counts, hormones and metabolic blood tests in elderly people (Khavinson & Morozov, 2003), and blood counts, lymphocyte subsets, C-reactive protein, IL-6, D-dimer and fibrinogen in adults hospitalized with COVID-19 (Kuznik et al., 2021; Khavinson et al., 2021).

Commonly Stacked With

The Khavinson group gave Thymalin together with the pineal extract Epithalamin in its 2003 study in elderly people (Khavinson & Morozov, 2003). No published study of Thymalin with Epitalon or N-Acetyl-Epithalon was found.

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References

1. Khavinson VKh, Morozov VG. Peptides of pineal gland and thymus prolong human life. Neuro Endocrinol Lett. 2003 Jun-Aug;24(3-4):233-240. PMID: 14523363. (266-patient elderly geroprotective trial; 6–8-year follow-up; mortality reductions of 2.0-fold for Thymalin alone, 2.5-fold for Thymalin + Epithalamin combination, 4.1-fold for the six-year annual combination sub-cohort vs untreated controls.)
2. Khavinson VKh, Morozov VG. [Geroprotective effect of thymalin and epithalamin]. Adv Gerontol. 2002;10:74-84. Russian. PMID: 12577695. (Russian-language companion publication of the elderly geroprotective trial.)
3. Khavinson VKh, Kuznik BI, Ryzhak GA. [Peptide bioregulators: the new class of geroprotectors. Message 2. Clinical studies results]. Adv Gerontol. 2013;26(1):20-37. Russian. PMID: 24003726. (Long-term clinical results across the Khavinson bioregulator family — Thymalin, Thymogen, Vilon, Epithalamin, Prostatilen, Cortexin, Retinalamin.)
4. Khavinson VK, Linkova NS, Kvetnoy IM, Polyakova VO, Drobintseva AO, Kvetnaya TV, Ivko OM. Thymalin: Activation of Differentiation of Human Hematopoietic Stem Cells. Bull Exp Biol Med. 2020 Nov;170(1):118-122. doi: 10.1007/s10517-020-05016-z. PMID: 33237528. (In vitro demonstration that Thymalin activates differentiation of human hematopoietic stem cells toward the lymphoid lineage, providing a candidate mechanism for clinical hematopoietic-recovery applications.)
5. Khavinson VK, Kuznik BI, Tarnovskaya SI, Linkova NS. Results and Prospects of Using Activator of Hematopoietic Stem Cell Differentiation in Complex Therapy for Patients with COVID-19. Stem Cell Rev Rep. 2021 Feb;17(1):285-290. doi: 10.1007/s12015-020-10087-6. PMID: 33575961. (Review proposing thymic peptides including Thymalin for COVID-19 immunorehabilitation based on hematopoietic stem cell differentiation and immunomodulatory mechanisms.)
6. Khavinson V, Linkova N, Dyatlova A, Kuznik B, Umnov R. Peptides: Prospects for Use in the Treatment of COVID-19. Molecules. 2020 Sep 24;25(19):4389. doi: 10.3390/molecules25194389. PMID: 32987757. (Computational and mechanistic review of Khavinson short peptides — including the dipeptides EW and KE released within the Thymalin complex — as candidate immunomodulators for COVID-19.)
7. Avolio F, Martinotti S, Khavinson VK, Esposito JE, Giambuzzi G, Marino A, Mironova E, Pulcini R, Robuffo I, Bologna G, Simeone P, Lanuti P, Guarnieri S, Trofimova S, Procopio AD, Toniato E. Peptides Regulating Proliferative Activity and Inflammatory Pathways in the Monocyte/Macrophage THP-1 Cell Line. Int J Mol Sci. 2022 Mar 30;23(7):3697. doi: 10.3390/ijms23073607. PMID: 35408963. (Italian-collaboration mechanistic study of Thymalin, Epitalon, Vilon, Thymogen, and Chonluten in human THP-1 monocytes; Khavinson Peptides act as inducers of TNF tolerance and anti-inflammatory modulators; one of the few non-Russian-affiliated mechanistic confirmations.)
8. Kuznik B, Khavinson V, Shapovalov K, Lukyanov S, Smolyakov Y, Tereshkov P, Shapovalov Y, Konnov V, Tsybikov N. Peptide Drug Thymalin Regulates Immune Status in Severe COVID-19 Older Patients. Adv Gerontol. 2021;11(4):360-367. doi: 10.1134/S2079057021040068. (Single-center Chita State Medical Academy trial — IRB-approved protocol no. 102, 15 May 2020 — in older severe-COVID-19 patients; Thymalin arm showed faster lymphopenia reversal, restoration of CD3+HLA-DR+, CD4+, B-, and NK-cell subpopulations, recovery of platelet/lymphocyte ratio, and reduced in-hospital mortality vs standard care.)
9. Khavinson VK, Kuznik BI, Volchkov VA, Rukavishnikova SA, Titova ON, Akhmedov TA, Trofimova SV, Ryzhak GA, Potyomkin VV, Saginbaev UR. Effect of thymalin on adaptive immunity in complex therapy for patients with COVID-19. Klinicheskaya Meditsina (Russian Journal). 2020;98(8):593-599. doi: 10.30629/0023-2149-2020-98-8-593-599. (Comparative IgG-to-SARS-CoV-2 dynamics with vs without Thymalin in COVID-19 patients.)
10. Lukyanov SA, Kuznik BI, Shapovalov KG, Khavinson VK, Smolyakov YN, et al. Thymalin as a Potential Alternative in the Treatment of Severe Acute Respiratory Infection Associated with SARS-CoV-2. Int J Immunol Immunother. 2020;7:055. (Severe-COVID-19 case treated with Thymalin 10 mg IM daily after failed lopinavir/ritonavir + hydroxychloroquine, with marked early clinical improvement.)
11. Morozov VG, Khavinson VKh. Natural and synthetic thymic peptides as therapeutics for immune dysfunction. Int J Immunopharmacol. 1997 Sep-Oct;19(9-10):501-505. doi: 10.1016/S0192-0561(97)00058-1. PMID: 9637345. (Foundational western-indexed paper describing Thymalin and the synthetic dipeptide derivative L-Glu-L-Trp / Thymogen, with reported activity on T-cell differentiation, T-cell recognition of peptide-MHC complexes, intracellular cyclic nucleotides, IL-2 and interferon excretion.)
12. Khavinson VKh. Peptides and Ageing. Neuro Endocrinol Lett. 2002;23 Suppl 3:11-144. PMID: 12374906. (Comprehensive Khavinson review of the peptide bioregulator program; Thymalin's immune-stimulating activity highlighted as the most prominent of its effects.)
13. Anisimov VN, Khavinson VKh, Morozov VG. Carcinogenesis and aging. IV. Effect of low-molecular-weight factors of thymus, pineal gland and anterior hypothalamus on immunity, tumor incidence and life span of C3H/Sn mice. Mech Ageing Dev. 1982 Jul;19(3):245-258. doi: 10.1016/0047-6374(82)90057-4. (Foundational Khavinson preclinical work supporting the geroprotection / carcinogenesis-attenuation framework that Thymalin clinical trials later built on.)
14. Kuznik BI, Makhakova GCh, Morozov VG, Pisarevskaia LI, Khavinson VKh. [Effect of thymalin on thrombocyte aggregation and the antiaggregation activity of the vascular wall in intact and thymectomized rats]. Biull Eksp Biol Med. 1986 Aug;102(8):200-202. Russian. PMID: 3754821. (Early characterization of Thymalin's effect on platelet hemostasis and the thymus-platelet axis; the 1980s foundation of the modern thrombo-inflammatory / COVID rationale.)
15. Khavinson VK, Lin'kova NS, Tarnovskaya SI. Short Peptides Regulate Gene Expression. Bull Exp Biol Med. 2016 Nov;162(2):288-292. doi: 10.1007/s10517-016-3596-7. PMID: 27909961. (Khavinson group's short-peptide DNA-binding / gene-expression-regulation hypothesis, the mechanistic frame underpinning the polypeptide-complex pharmacology argument for Thymalin.)
16. Khavinson V, Popovich I. Short Peptides Regulate Gene Expression, Protein Synthesis and Enhance Life Span. In: Vaiserman AM (ed.). Anti-aging Drugs: From Basic Research to Clinical Practice. RSC Drug Discovery Series No. 57. Royal Society of Chemistry; 2017. Chapter 20, pp. 496–513. doi: 10.1039/9781782626602-00496. (Book chapter elaborating the Khavinson short-peptide gene-expression hypothesis and its application to Thymalin and the bioregulator family.)
17. Khavinson V, Linkova N, Diatlova A, Trofimova S. Peptide Regulation of Cell Differentiation. Stem Cell Rev Rep. 2020 Feb;16(1):118-125. doi: 10.1007/s12015-019-09938-8. PMID: 31808038. (Mechanistic review of short-peptide regulation of cell differentiation, including thymic and hematopoietic lineages relevant to Thymalin's pharmacology.)
18. Linkova NS, Drobintseva AO, Orlova OA, Kuznetsova EP, Polyakova VO, Kvetnoy IM, Khavinson VK. Peptide Regulation of Skin Fibroblast Functions during Their Aging In Vitro. Bull Exp Biol Med. 2016 May;161(1):175-178. doi: 10.1007/s10517-016-3370-x. PMID: 27259496. (Khavinson short-peptide bioregulator activity on aging fibroblasts; complements the broader bioregulator framework Thymalin sits within.)
19. Khavinson VKh. Peptide medicines: past, present, future. Klinicheskaya Meditsina (Russian Journal). 2020;98(3):165-177. doi: 10.30629/0023-2149-2020-98-3-165-177. (Khavinson historical and prospective overview of the Russian peptide-bioregulator program — Thymalin, Epithalamin, Cortexin, Prostatilen, Retinalamin — developed at the Military Medical Academy named after S.M. Kirov.)
20. FDA. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the FD&C Act (503A categories list), versions updated April 15, April 22 and May 14, 2026. fda.gov/media/94155/download. Read October 3, 2026. (Notice that 12 peptides would leave Category 2 because their nominations were withdrawn; their removal; GHK-Cu, except injectable, back in Category 1.)
21. Samson-Med. Тималин (Thymalin; thymus extract), lyophilizate for solution for intramuscular injection, 10 mg: instructions for medical use. Copy in the GEOTAR drug database: files.dev.lsgeotar.ru/public/1zaLIvWEPmOcOYHIHbfKJQ.pdf; current registration ЛП-№(005867)-(РГ-RU) of June 21, 2024 (previously ЛС-000267), per vidal.ru/drugs/thymalin__23838. Read October 3, 2026. (In Russian. Doses for adults and children, contraindications, allergic reactions as the side effect, interactions, storage at no more than 25 °C, 3-year shelf life.)
22. World Anti-Doping Agency. Prohibited List 2026 (in effect January 1, 2026). S0, Non-approved substances. wada-ama.org/sites/default/files/2025-09/2026list_en_final_clean_september_2025.pdf. Read October 3, 2026.

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• ThymagenKhavinson Thymic Immune Bioregulator
• LivagenKhavinson Lymphoid / Hepatic Bioregulator
• Thymosin Alpha-1Endogenous Thymic Immunomodulator
• ThymulinThymic Hormone, Zinc-Dependent Nonapeptide
• FDA TrackerPCAC voted on 7 of the 12 peptides on July 23–24, 2026; FDA plans a PCAC review of the other 5 before the end of February 2027.