Plerixafor and Granulocyte Colony-stimulating Factor (G-CSF) With Busulfan, Fludarabine and Thymoglobulin

The goal of this clinical research study is to learn about the safety of AMD3100 (plerixafor) and G-CSF (filgrastim) in combination with fludarabine, busulfan, and an allogeneic blood stem cell transplant. This treatment will be studied in patients with acute myeloblastic leukemia (AML), myelodysplastic syndromes (MDS), or Chronic myelogenous leukemia (CML).

The Study Treatment:

Fludarabine is a chemotherapy drug that is designed to make cancer cells less able to repair damaged DNA (the genetic material of cells). This may increase the likelihood of the cells dying.

Busulfan is a chemotherapy drug that is designed to bind to DNA, which may cause cancer cells to die. It is commonly used in stem cell transplants.

Plerixafor and filgrastim are designed to cause cancer cells to move from the bone marrow into the blood stream. This may help to make the cancer cells more sensitive to being killed by the chemotherapy.

An "allogeneic" (from a donor) stem cell transplant is designed to help the recipient's body attack the cancer cells that may remain in the body after chemotherapy.

Study Groups and Plerixafor Dose Levels:

If you are found to be eligible to take part in this study, you will be assigned to a study group based on when you joined this study. Up to 4 groups of 3 participants will be enrolled in the Phase I portion of the study, and up to 48 participants will be enrolled in Phase II.

If you are enrolled in the Phase I portion, the dose of plerixafor you receive will depend on when you joined this study. The first group of participants will receive the lowest dose level of plerixafor. Each new group will receive a higher dose of plerixafor than the group before it, if no intolerable side effects were seen. This will continue until the highest tolerable dose of plerixafor is found.

If you are enrolled in Phase II, you will receive plerixafor at the highest dose that was tolerated in the Phase I portion.

In this study, plerixafor is the only study drug where different dose levels are being tested and compared.

Drug Administration Before the Transplant:

You will receive your first dose of filgrastim on Day -9. (Day -9 means 9 days before the stem cell transplant, which will occur on Day 0).

Filgrastim is injected under the skin once a day from Day -9 through Day -4. Plerixafor is injected under the skin once a day from Day -7 through Day -4. The plerixafor injections will occur 8 hours before the fludarabine and busulfan chemotherapy.

The fludarabine and busulfan will be given by vein through a central venous catheter (CVC). A CVC is a sterile flexible tube that will be placed into a large vein while you are under local anesthesia. Your doctor will explain this procedure to you in more detail, and you will be required to sign a separate consent form for this procedure.

Fludarabine is given once a day from Day -6 through Day -3, over 1 hour each time. On these same days, busulfan will be given after the fludarabine, over 3 hours.

You will also receive tacrolimus in order to lower the risk of graft vs. host disease (GVHD). GVHD is a disease that occurs when the donor's immune cells react against the recipient's body, attacking the recipient's cells and tissues.

Starting on Day -2, tacrolimus will be given as a continuous (non-stop) infusion through the CVC. When the study doctor decides it seems safe, you will begin taking tacrolimus by mouth instead, for as long as the study doctor decides is necessary.

If your stem cell donor is not someone who is related to you, you will receive antithymocyte globulin (ATG) through the CVC once a day from Day -3 through Day -1. On Day -3, it will be given over at least 6 hours. On Days -2 and -1, it will be given over at least 4 hours. This drug is given in order to weaken your immune system in order to lower the risk of your immune system rejecting the transplanted cells.

Blood Tests Before the Transplant:

If you are in the Phase I part of this study, the following blood samples will be drawn and are not optional. Eight total blood samples (about 1 1/2 teaspoons each) will be drawn daily with your routine morning labs beginning before your first dose of study therapy (or Day -9) through Day -3. These samples will be used for research purposes, to study how the chemotherapy drugs and transplant may affect your normal cells and cancerous cells.

If you are in the Phase II part of the study the following blood samples are optional and if you agree, eight total blood samples (about 1 1/2 teaspoons each) will be drawn daily beginning before your first dose of study therapy (or Day -9) through Day -3. These samples will be used for research purposes, to study how the chemotherapy drugs and transplant may affect your normal cells and cancerous cells.

Stem Cell Transplant:

On Day 0, after 2 days of rest from chemotherapy, the donor's stem cells will be given to you by vein (through the CVC). This should take about 30-60 minutes.

Drug Administration After the Transplant:

In addition to continuing to receive tacrolimus to lower the risk of GVHD (as described above), after the transplant you will also receive methotrexate to lower the risk of GVHD. Methotrexate will be given by vein, through the CVC, over 15 minutes on Days 1, 3, and 6. It will also be given on Day 11 if your stem cell donor is someone who is not related to you.

Once a day, starting at 1 week after the transplant, you will receive filgrastim as an injection under your skin. These daily injections will continue until your blood counts recover.

Reasons for Stopping the Study Treatment Early:

If you experience intolerable side effects or the disease gets worse during study treatment, you will be taken off the study treatment.

Other Procedures After the Transplant:

You will remain in the hospital until your blood counts recover (usually about 4 weeks after the transplant). You will continue being monitored for any infections and transplant-related side effects for at least 100 days after the transplant.

At 1, 3, 6, and 12 months after the transplant, you will have blood tests (about 3 tablespoons) and bone marrow biopsies performed to check the status of the disease.

Length of Study Participation:

Your active participation in this study will be over at 12 months after the transplant. The study staff will continue to contact your local doctor regularly from then on. The purpose is to check the status of the disease and see how you are doing.

Up to 72 patients will take part in this study. All will be enrolled at The University of Texas (UT) MD Anderson.

Eligibility Criteria:
Inclusion Criteria:

1. Patients age \>/=18 to \</= 65 years.
2. Diagnosis of AML in first or greater remission, first or subsequent relapse, or primary induction failure; MDS with intermediate or high risk International Prognostic Scoring System (IPSS) score having failed to respond or recurred after chemotherapy; in remission or having active disease after treatment; AML arising from MDS; or CML which has failed to respond to imatinib or other tyrosine kinase inhibitor and has had \>5% blasts in the blood or bone marrow. Patients receiving second transplants after relapse are considered in the relapse group.
3. White Blood Count (CBC) \</= 20 \* 10\^9/l.
4. Patients should have a histocompatible, related or unrelated volunteer donor available. A histocompatible donor is defined as HLA matched related donor or an unrelated donor matched for HLA- A, B, C, and DR antigens by high-resolution DNA techniques.
5. Zubrod performance status 0 or 1, or Karnofsky performance status 90-100%.
6. Left ventricular ejection fraction \>/= 45 %. No uncontrolled arrhythmias or uncontrolled symptomatic cardiac disease.
7. No symptomatic pulmonary disease. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and diffusion capacity of carbon monoxide (DLCO) \>/= 50 % of expected, corrected for hemoglobin.
8. Serum creatinine \</=1.5 mg/dl.
9. Serum glutamic pyruvic transaminase (SGPT) \</= 200 IU/ml unless related to the malignancy.
10. Total serum bilirubin \</=1.5 mg/dl (unless Gilbert's syndrome) and alkaline phosphatase \</=2.5 times laboratory standard upper limit of normal (ULN).
11. Patient or patient's legal representative able to sign informed consent.

Exclusion Criteria:

1. History of HIV positive.
2. Positive Beta human chorionic gonadotropin (HCG) test in a woman with child bearing potential defined as not post-menopausal for 12 months or no previous surgical sterilization.
3. Pleural/pericardial effusion or ascites estimated \>/= 1 liter.
4. Uncontrolled infection, not responding to appropriate antimicrobial agents after seven days of therapy.
5. History of acute hepatitis, chronic active hepatitis or cirrhosis.
6. Patients with class 3 or 4 angina (New York Heart Association (NYHA) criteria).