Thymalin

Thymalin is a polypeptide complex extracted from calf thymus gland, developed by V.G. Morozov and V.Kh. Khavinson at the St. Petersburg Institute of Bioregulation and Gerontology in the 1970s and registered as a pharmaceutical in Russia since 1982 (Samson-Med, Roszdravnadzor LS-000267). Unlike Thymulin (FTS, a single zinc-dependent nonapeptide), Thymalin is a multi-component mixture with characterized active fragments including the EW dipeptide (Glu-Trp, marketed separately as Thymogen), KE (Lys-Glu, marketed as Vilon), and EDP (Glu-Asp-Pro, marketed as Crystagen). The complex acts as a thymic bioregulator: it accelerates T-lymphocyte maturation from CD117+ hematopoietic progenitors, restores B and T lymphocyte ratios, and modulates pro-inflammatory cytokines (TNF-alpha, IL-6, IL-1beta) via epigenetic gene regulation. Clinical use in Russia covers immunodeficiency states, post-radiotherapy and post-chemotherapy immune recovery, bronchial asthma, and impaired tissue regeneration. A small open-label RCT (n=92) in 2021 reported reduced inflammatory markers in hospitalized COVID-19 patients, and a 6-8 year observational geroprotective study (n=266) reported reduced all-cause mortality in elderly subjects. Nearly all clinical evidence originates from the Khavinson research group, and no independent Western replication has been published.

• Age-Related Immune Decline
• T-Cell Maturation
• Cytokine Suppression

Immune reconstitution, T-cell maturation from progenitors, modulation of pro-inflammatory cytokines, supportive use during/after immunosuppressive therapy

Accelerates differentiation of CD117+ hematopoietic progenitors into mature CD28+ T-lymphocytes. Constituent EW and KE dipeptides bind specific DNA motifs (GGAG and GCGC respectively) and act as epigenetic modulators of cytokine gene expression. Downstream effects include reduced TNF-alpha, IL-6, and IL-1beta, restored CD4+/CD8+ ratios, and increased phagocytic activity.

Peak plasma concentration: 3 min. Elimination half-life: 30 min. Largely cleared by: ~2.5 hrs.

Research protocols from published literature — not dosing recommendations.

• Thymulin — Use Caution: Thymalin and Thymulin are frequently confused but are different compounds. Thymulin is a single 9-amino-acid zinc-dependent metallopeptide (FTS). Thymalin is a multi-peptide thymic extract containing EW, KE, EDP and other fragments. They share the thymic bioregulator class but have different mechanisms and dosing. Verify the product label before use.
• Epitalon — Synergistic: The original Khavinson geroprotective protocols pair Thymalin (thymic axis) with Epitalon or Epithalamin (pineal axis). The 6-8 year longevity trial in elderly subjects used annual courses of both, and reported larger mortality reductions for the combination than for either alone.
• Thymosin Alpha-1 — Compatible: Both target thymic-axis immunity but via different mechanisms. Thymosin Alpha-1 is a single synthetic 28-amino-acid peptide acting on TLR signaling. Thymalin is a multi-peptide extract acting partly via epigenetic regulation through KE and EW dipeptide constituents. No direct comparison studies, but mechanisms appear complementary.
• Thymogen (EW) — Use Caution: Thymogen (Glu-Trp / EW dipeptide) is one of Thymalin's identified active constituents, now manufactured as a standalone synthetic peptide. Co-administration is redundant rather than synergistic: anyone using Thymalin is already receiving EW activity. Stacking risks unnecessary duplication of effect.
• Pinealon — Compatible: Both are Khavinson-developed bioregulators targeting different tissue axes (Pinealon = pineal/neuroprotective tripeptide; Thymalin = thymic/immune). Used together in Russian gerontology protocols. No published interaction data.
• Corticosteroids — Monitor Combination: Chronic corticosteroid therapy suppresses thymic function. Thymalin's clinical rationale partly involves reversing this suppression. No formal interaction studies; theoretical interest as a steroid-sparing adjunct in autoimmune protocols, but no clinical data supports unsupervised co-use.
• Immunosuppressants (transplant) — Avoid Combination: Thymalin's mechanism (accelerating T-cell maturation, increasing CD4+/CD28+ populations) is directionally opposite to post-transplant immunosuppression. Use in solid organ or bone marrow transplant recipients has not been studied and is theoretically contraindicated.
• Chemotherapy / Radiotherapy — Monitor Combination: Approved indication on the Russian label includes immune recovery after chemotherapy and radiotherapy. Cochrane class-level review of thymic peptides in cancer (PMID 21328265, not Thymalin-specific) showed reduced severe infection risk without survival benefit. Coordinate with the treating oncologist before combining.

Supplies:

• Thymalin lyophilized powder (typically 10 mg vial)
• 0.9% sterile sodium chloride (preferred per Russian label)
• IM-appropriate syringe (23-25 gauge, 1-1.5 inch)
• Alcohol prep pads

1. 1Store lyophilized vials at 2-8°C until use
2. 2Allow vial to reach room temperature for 5-10 minutes
3. 3Reconstitute with 1-2 mL of 0.9% sodium chloride immediately before injection
4. 4Add solvent slowly down the vial wall; do not shake
5. 5Gently swirl until fully dissolved (solution should be clear)
6. 6Draw the full reconstituted volume into a single syringe
7. 7Inject IM into deltoid, vastus lateralis, or gluteal muscle
8. 8Do not store reconstituted product; use the same day

Day 1-3: No immediately perceptible effects expected. Day 7-10: In the COVID-19 RCT, lymphocyte and CD4+ counts increased and IL-6 / CRP / D-dimer decreased over this window. Single course: Effects on infection rates and immune markers reported over weeks to months. Geroprotective use: Outcomes assessed over multiple annual cycles, not single courses. Source quality matters: a multi-peptide extract is more batch-dependent than a synthetic peptide.

Russian label contraindications: known hypersensitivity to thymic proteins, pregnancy, lactation. No widely reported organ-specific toxicity in published clinical use. AE reporting in published trials does not meet modern ICH/CTCAE standards; absence of reported events is not equivalent to demonstrated safety. Not studied in solid organ or bone marrow transplant recipients on immunosuppression. Not studied in active autoimmune disease; theoretical concern with pro-T-cell mechanism. Not FDA-approved or EMA-approved. Use during oncology treatment should be coordinated with the treating oncologist.

Russian label contraindications: known hypersensitivity to thymic proteins, pregnancy, lactation. No widely reported organ-specific toxicity in published clinical use. AE reporting in published trials does not meet modern ICH/CTCAE standards; absence of reported events is not equivalent to demonstrated safety. Not studied in solid organ or bone marrow transplant recipients on immunosuppression. Not studied in active autoimmune disease; theoretical concern with pro-T-cell mechanism. Not FDA-approved or EMA-approved. Use during oncology treatment should be coordinated with the treating oncologist.

Thymalin should be stored at Lyophilized: 2-8°C. Reconstituted: use immediately, do not store..