A randomized trial to evaluate the immunorestorative properties of synthetic thymosin-alpha 1 in patients with lung cancer.
A randomized trial was performed in 42 postradiotherapy patients with non-small cell lung cancer to determine whether the administration of synthetic thymosin-alpha 1 by either a loading dose or a twice-weekly schedule could accelerate the reconstitution of thymic dependent immunity. The radiotherapy-induced immunosuppression was characterized by an absolute T cell lymphopenia and by impaired T cell function in lymphoproliferative assays. Placebo-treated patients did not show any improvement in T cell numbers or function over 15 weeks of serial immune monitoring, and exhibited gradual depressions of helper T lymphocyte percentages. Patients treated with thymosin by the loading dose regimen exhibited a normalization of T cell function (p = 0.04), whereas patients treated with the twice-weekly schedule maintained normal helper T cell percentages (p = 0.04). Thymosin treatment was associated with significant improvements in relapse-free and overall survival, which was most pronounced for patients with nonbulky tumors. Thymosin-alpha 1 exhibits schedule-dependent immune restorative and homeostatic properties. Large scale Phase III trials are indicated to definitively establish the impact of thymosin therapy in lung cancer patients treated with radiotherapy.
D000276:Adjuvants, Immunologic; D000368:Aged; D004341:Drug Evaluation; D005260:Female; D006801:Humans; D007111:Immunity, Cellular / Q000187:drug effects / Q000528:radiation effects; D007165:Immunosuppression Therapy; D008175:Lung Neoplasms / Q000276:immunology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D011832:Radiation Injuries; D011897:Random Allocation; D000077596:Thymalfasin; D013947:Thymosin / Q000031:analogs & derivatives* / Q000627:therapeutic use
D000276:Adjuvants, Immunologic; D013947:Thymosin; D000077596:Thymalfasin