The STIR trial

Phase 2 solid tumor immunotherapy trial using HLA-haploidentical transplant and donor natural killer cells

Children’s Wisconsin is currently enrolling patients with solid tumors on a Phase II immunotherapy trial, coupling bone marrow transplant with donor Natural Killer (NK) cells in patients with:

• Ewing’s Sarcoma
• Osteosarcoma
• Rhabdomyosarcoma
• Neuroblastoma
• Wilm’s Tumor
• Medulloblastoma
• Primitive neuro-ectodermal tumor (PNET)
• Ependymoma
• High grade (Grade 3 or 4) glioma or astrocytoma
• Germ-cell tumor
• Atypical teratoid-rhabdoid tumor (ATRT)

One of our blood and marrow transplant program physicians, Dr. Monica Thakar, is the lead investigator of this trial. Children’s is one of two sites in the country where this trial is available. Children's is the coordinating site for the trial and have an affiliate site (Froedtert Hospital) for adult patients.

Conventional approaches for treating high-risk solid tumors include chemotherapy, radiation therapy, and surgeries. While these treatments are necessary, the side effects can be substantial. The purpose of this study is to evaluate the safety and efficacy of performing a unique dual immunotherapy approach to treating high-risk solid tumors. Patients will receive a haploidentical (half-matched) allogeneic bone marrow transplant followed by NK cell infusion.

Bone marrow transplant involves removing stem cells from a healthy donor (in this case, a partially-matched haploidentical family member), and transferring them to the patient. To prepare for the new stem cells, patients will be given a reduced intensity (low toxicity) conditioning regimen to try to suppress their immune system so that it does not reject the new cells. Donor stem cells are then infused into the patient. The new stem cells will settle in the patient’s body and produce new blood and immune cells to replace the destroyed cells. It is known that the new immune system from the donor HPCs may also fight the recipient’s cancer cells.

This study is also asking whether the addition of extra immune cells from the same haploidentical donor one week after transplant is safe and can help treat the recipient’s cancer and prevent relapse. These cells are known as natural killer cells or NK cells. The addition of NK cells is considered part of the investigational therapy.

Our BMT program is FACT (Foundation for the Accreditation of Cellular Therapy) accredited and has performed over 1,100 bone marrow transplants. Children’s was ranked in the U.S. News & World Report Best Children’s Hospitals list.