Biomodulina T (InmunyVital®) is a thymic factor that modulates immune response and inflammation. Biomodulina T stimulates the differentiation, maturation and proliferation of T cells. Additionally, Biomodulina T improves the ability of T cells to produce cytokines, therefore enhancing T lymphocyte function. Biomodulina T stimulates the thymus gland and, thus, promotes the recovery of normal thymus size in children with thymic hypoplasia and restores the functions of immunosenescent T cells in aging people. In 1984 Rodriguez Martin RR established the laboratory of Biomodulators, where he created and developed an immunomodulatory thymic factor that he named “Biomodulina T.” The biological activity of Biomodulina T was demonstrated in several studies. An extensive series of preclinical toxicological studies were conducted and these studies demonstrated that Biomodulina T is an active and safe thymic factor. Clinical trials were conducted with Biomodulina T in patients with immunodeficiency and infections, autoimmune diseases, older adults with recurrent respiratory infections, and cancer. In 1994, we obtained the approval of Biomodulina T as an immunomodulatory drug. This article identifies the milestones involved in the development of Biomodulina T. Since its discovery more than 35 years ago, reports show that Biomodulina T is a modulator of immune response and inflammation that is very useful for restoring the immune system in young and elderly people with immunodeficiencies, autoimmune diseases, and infections. Biomodulina T is also useful as an immunotherapeutic agent for improving immune responses in cancer and vaccines, for reversing immunosenescence and for improving healthspan in aging.Copyright © 2023 Elsevier B.V. All rights reserved.