NCT04579523

²¹¹At-OKT10-B10 and Fludarabine Alone or in Combination With Cyclophosphamide and Low-Dose TBI Before Donor Stem Cell Transplant for the Treatment of Newly Diagnosed, Recurrent, or Refractory High-Risk Multiple Myeloma

A Phase I Trial Evaluating Escalating Doses of ²¹¹At-Labeled Anti-CD38 Monoclonal Antibody Followed by HLA-Matched or Haploidentical Donor Hematopoietic Cell Transplantation for High-Risk Multiple Myeloma

• Status: Not Yet Recruiting
• Phase: Phase 1
• Study type: Interventional
• Enrollment: 30 (estimated)
• Sponsor: Fred Hutchinson Cancer Center · Academic / Other
• Sex: All
• Age: 18 Years – 70 Years
• Healthy volunteers: Not accepted

Summary

This phase I trial investigates the side effects and best dose of ²¹¹At-OKT10-B10 when given together with fludarabine, alone or in combination with cyclophosphamide and low-dose total-body irradiation (TBI) before donor stem cell transplant in treating patients with high-risk multiple myeloma that is newly diagnosed, has come back (recurrent), or does not respond to treatment (refractory). ²¹¹At-OKT10-B10 is a monoclonal antibody, called OKT10-B10, linked to a radioactive agent called ²¹¹At. OKT10-B10 attaches to CD38 positive cancer cells in a targeted way and delivers ²¹¹At to kill them. Chemotherapy drugs, such as fludarabine and cyclophosphamide, work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Radiation therapy such as TBI uses high energy x-rays to kill cancer cells and shrink tumors. Giving ²¹¹At-OKT10-B10 together with chemotherapy and TBI before a donor stem cell transplant helps kill cancer cells in the body and helps make room in the patient's bone marrow for new blood-forming cells. When the healthy stem cells from a donor are infused into a patient, they may help the patient's bone marrow make more healthy cells and platelets and may help destroy any remaining cancer cells.

Detailed description

OUTLINE: This is a dose-escalation study of ²¹¹At-OKT10-B10. Patients are assigned to 1 of 2 arms. ARM A: Patients with HLA-matched related or unrelated donors receive ²¹¹At-OKT10-B10 intravenously (IV) on day -7 (day -10 to -5) and fludarabine IV over 30 minutes on days -4 to -2. Patients then undergo TBI and allogeneic HCT on day 0. Additionally, patients undergo x-rays on study, and blood sample collection, bone marrow biopsy, and bone marrow aspiration throughout the study. ARM B: Patients with HLA-matched haploidentical donors receive ²¹¹At-OKT10-B10 IV on day -8 (day -14 to -7), fludarabine IV over 30 minutes on days -6 to -2, and cyclophosphamide IV over 1 hour on day -6 and -5. Patients then undergo TBI on day -1 and allogeneic HCT on day 0. Additionally, patients undergo x-rays on study, and blood sample collection, bone marrow biopsy, and bone marrow aspiration throughout the study. After completion of study treatment, patients are followed up at 9, 12, 18 and 24 months.

Conditions

• Multiple Myeloma
• Recurrent Multiple Myeloma
• Refractory Multiple Myeloma

Interventions

Type	Name	Description
PROCEDURE	Allogeneic Hematopoietic Stem Cell Transplantation	Undergo HCT
BIOLOGICAL	Astatine At 211 Anti-CD38 Monoclonal Antibody OKT10-B10	Given IV
DRUG	Cyclophosphamide	Given IV
DRUG	Fludarabine Phosphate	Given IV
RADIATION	Total-Body Irradiation	Undergo TBI
PROCEDURE	Biospecimen Collection	Undergo blood collection
PROCEDURE	Bone Marrow Aspiration	Undergo bone marrow aspirate
PROCEDURE	Bone Marrow Biopsy	Undergo bone marrow biopsy
PROCEDURE	X-Ray Imaging	Undergo chest x-rays

Timeline

• Start date: 2026-06-01
• Primary completion: 2027-12-31
• Completion: 2028-12-31
• First posted: 2020-10-08
• Last updated: 2026-03-13

Locations

1 site across 1 country: United States

Regulatory

• FDA-regulated drug study