Henry G Withers

mTOR inhibition modulates vaccine-induced immune responses to generate memory T cells in patients with solid tumors

Background Perturbation of the mechanistic target of rapamycin (mTOR) pathway can instruct effector versus memory cell fate of tumor antigen-specific T cells in preclinical models. In this study, we sought to understand the impact of rapamycin (sirolimus), an mTOR inhibitor, on reprogramming vaccine-induced T cells to enhance memory responses in patients with solid tumors following completion of their standard therapy. Methods We conducted three phase I clinical trials employing New York esophageal squamous cell carcinoma-1 (NY-ESO-1) vaccination approaches, with or without schedule-varied rapamycin. T cell phenotypes, functions, and Vβ usage in peripheral blood were analyzed to ask whether rapamycin influenced the generation of vaccine-induced T cells with memory attributes. Results The addition of rapamycin to all vaccination approaches was safe and well tolerated. Immediate (days 1–14 postvaccination) or delayed (days 15–28 postvaccination) administration of rapamycin led to a significant increase in the generation of vaccine-induced NY-ESO-1-specific T cells exhibiting central memory phenotypes (CD45RO+CD45RA− CCR7+). Moreover, delayed administration resulted in a greater than threefold (p=0.025) and eightfold (p=0.005) increase in the frequency of NY-ESO-1-specific CD4+ T and CD8+ T cells respectively at the time of long-term follow-up, compared with its immediate usage. Conclusion Our novel finding is that delayed administration of rapamycin to patients during the contraction phase of vaccine-induced antitumor immune responses was particularly effective in increasing the frequency of memory T cells up to 1 year postvaccination in patients with solid tumors. Further studies are warranted to identify the impact of this approach on the durability of clinical remission. Trial registration number NCT00803569, NCT01536054, NCT01522820.

Sirolimus and Vaccine Therapy in Treating Patients With Stage II-IV Ovarian Epithelial, Fallopian Tube, or Primary Peritoneal Cavity Cancer

This phase I trial studies the side effects and best dose and schedule of sirolimus when given together with vaccine therapy in treating patients with stage II-IV ovarian epithelial, fallopian tube, or primary peritoneal cavity cancer. Sirolimus may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Vaccines made from a gene-modified virus may help the body build an effective immune response to kill tumor cells. Giving vaccine therapy together with sirolimus may be an effective treatment for ovarian, fallopian tube, or primary peritoneal cancer

Vaccine Therapy With or Without Sirolimus in Treating Patients With NY-ESO-1 Expressing Solid Tumors

This phase I trial studies the side effects and best schedule of vaccine therapy with or without sirolimus in treating patients with cancer-testis antigen (NY-ESO-1) expressing solid tumors. Biological therapies, such as sirolimus, may stimulate the immune system in different ways and stop tumor cells from growing. Vaccines made from a person's white blood cells mixed with tumor proteins may help the body build an effective immune response to kill tumor cells that express NY-ESO-1. Infusing the vaccine directly into a lymph node may cause a stronger immune response and kill more tumor cells. It is not yet known whether vaccine therapy works better when given with or without sirolimus in treating solid tumors.

Vaccine Therapy in Stage II, III, or IV Epithelial Ovarian, Fallopian Tube, or Primary Peritoneal Cancers

This was a Phase 1, non-randomized, open-label, multicenter study of the ALVAC(2)-NY-ESO-1(M)/TRICOM vaccine administered with the granulocyte macrophage-colony stimulating factor (GM-CSF) sargramostim in patients with NY-ESO-1- or LAGE-1-positive epithelial ovarian, fallopian tube, or primary peritoneal cavity cancers who had completed standard therapy for primary or recurrent disease and would have normally entered a period of observation. The primary study objective was to determine the safety and tolerability of study vaccination, with secondary objectives including the determination of clinical and immunological responses.