Malignant osteopetrosis is a rare genetic disease in which bone resorption cells do not function properly. These cells are unable to perform their biological job of breaking down old bone tissue as new bone tissue is being made. This causes the bone tissue to build up, producing thick bones that do not work properly and causing the child to lose his/her bone marrow space, where red cells, platelets, and white cells are made. These children have hepatosplenomegaly from extramedullary hematopoiesis,and can have vision and hearing loss secondary to cranial nerve encroachment from the stenosis of formina.Stem cell transplantation from an allogeneic donor is the only known cure for this disease. Stem cells are immature cells found in the bone marrow that can grow into other kinds of cells. An allogeneic donor is another person who provides the stem cells. There are three types of donors:

A matched sibling donor (brother or sister) is the ideal treatment, but is not possible for the majority of patients.

A matched unrelated donor may also be used, but finding such a match may take several months. During this time the disease may get worse; the child may need red cell or platelet transfusions as the child may be unable to make these cells and permanent damage to vision and hearing may occur.

A haploidentical parental donor (a mother or father) may be feasible for the treatment for malignant osteopetrosis if a T-cell depleted graft is used.

This study is designed to use a haploidentical parental donor in the event that a matched sibling donor is unavailable. Using a parental donor would enable transplantation earlier in the disease process than waiting for a matched unrelated donor. This might reduce the chance of the disease getting worse before the transplant is done. With a parental donor, the risk of graft rejection (the patient’s body does not accept and allow the donor cells to grow) may be greater than the risk of rejection using a matched sibling donor. The purpose of this study is to learn more about the cause and treatment of malignant osteopetrosis. It is designed to determine if children with malignant osteopetrosis can properly accept a parental donor transplant and to study the genetic (characteristics carried by genes) factors which cause the disease.

Condition	Intervention
Malignant Osteopetrosis	Procedure: using the CliniMACS selection system  Drug: CD3 depleted graft by OKT3

Further Study Details: 

Primary Outcomes: To determine the feasibility of engraftment by 100 days after transplantation for children with osteopetrosis who receive a haploidentical hematopoietic stem cell graft.
Secondary Outcomes: To study the outcome (good and bad) of stem cell transplantation in children with malignant osteopetrosis one year after transplant who receive either a matched sibling donor transplant or a haploidentical stem cell transplant.; To study the genetics of patients, parents and siblings of children with malignant osteopetrosis
Expected Total Enrollment:  10

Genders Eligible for Study:  Both

Criteria

Inclusion Criteria:

• A confirmed diagnosis of malignant osteopetrosis
• Availability of a suitable stem cell donor
• Adequate cardiac (heart), hepatic (liver), and renal (kidney) function
• No evidence of current severe infection

Please refer to this study by ClinicalTrials.gov identifier  NCT00145587

Kimberly A Kasow, DO      1-866-278-5833    Kimberly.kasow@stjude.org

Tennessee
      St. Jude Children''''s Research Hospital, Memphis,  Tennessee,  38105,  United States; Recruiting

Study chairs or principal investigators

Kimberly A Kasow, DO,  Principal Investigator,  St. Jude Children''''s Research Hospital   

Study ID Numbers:  OPBMT2
Last Updated:  September 2, 2005
Record first received:  September 1, 2005
ClinicalTrials.gov Identifier:  NCT00145587
Health Authority: United States: Food and Drug Administration
ClinicalTrials.gov processed this record on 2005-09-06