Overall, we found neither evidence that the addition of pTE to antineoplastic treatment reduced the risk of death or disease progression nor that it improved the rate of tumour responses to antineoplastic treatment. For thymosin α1, there was a trend for a reduced risk of dying and of improved DFS. There was preliminary evidence that pTE lowered the risk of severe infectious complications in patients undergoing chemotherapy or radiotherapy.
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.