This summary is intended to provide a general overview of the Children's Oncology Group study ACCL1333. It tells who can be in this study and other basic information. The informed consent form has more details of the study. This document is available from your oncologist.

ACCL1333 is a Cancer Control and Supportive Care (CCLSC) Study. CCLSC studies are performed to help learn how to best deal with or prevent complications of cancer and cancer treatment. CCLSC studies often focus on complications that affect how people feel or what they can do during or after treatment (physical and emotional quality of life).

If you consent to being a part of this study, you or your child will receive one of two different treatment plans. The treatment plan is decided by a process called randomization. Randomization means that the treatment is assigned based on chance. It is a lot like flipping a coin, except that it is done by computer. Assigning children randomly assures that each child has a fair and equal chance of being assigned to either of the treatments. We do not know which treatment is better until all the children taking part in the clinical trial have completed treatment. However, if one of the treatments is found to be better than the others while the trial is still going on, the trial is stopped, and all children are given the better treatment. The randomization process is described in the COG Family Handbook for Children with Cancer.

Participating in a clinical trial is voluntary. The decision about whether or not to participate will not affect the care provided by the health care team in any way. You can find more information about clinical trials at  You can discuss any questions with your treatment team.

Study Number


Official Title

A Phase III Randomized, Open Label, Multi-center Study of the Safety and Efficacy of Apixaban for Thromboembolism Prevention versus No Systemic Anticoagulant Prophylaxis during Induction Chemotherapy in Children with Newly Diagnosed Acute Lymphoblastic Leukemia or Lymphoma (T or B cell) Treated with Pegylated Asparaginase

Study Opening Date

ACCL1333 opened on March 26th 2015. The ACCL1333 study committee hopes to enroll 500 patients. It is expected that this study will remain open through 2019.

General Patient Eligibility

General Background and Study Goal

About 5% of children with Acute Lymphoblastic Leukemia or Lymphoma will develop a blood clot during therapy. Most blood clots develop in the first month of therapy. This study will compare the rate of blood clots and bleeding in two groups. One group will receive Apixaban, a medicine that may prevent clots during Induction therapy. The other group will not receive this medication.

Summary of the Treatment

Children will be assigned to a study arm by randomization. There is an equal chance of being assigned to either study arm.

Children on the study arm that will receive treatment with Apixaban must have a platelet count greater than 20,000 before starting treatment with the medication. Apixiban is an oral medication taken daily for about one month. It will be held prior to spinal taps and if the platelet count gets very low. Children will be monitored closely for any bleeding.

Children who do not receive Apixaban will receive standard supportive care and monitoring.

Special Considerations

Children on both study arms on ACCL1333 will have imaging including an ultrasound and echocardiogram at the end of the month long trial.

Patients that are pregnant or breast-feeding are not eligible for this study.

Risks and Side Effects

All patients will be closely monitored to reduce the likelihood of negative side effects. All risks and side effects will be explained in detail by your healthcare team during the consent process. They can answer any questions that you may have regarding participation on the clinical trial or other aspects of care. Please refer to the consent document for a detailed explanation of the side effects associated with the treatment on this study

Contact Information

Your child’s oncologist and nurses are the best sources for further information

Principal Investigator

Sarah O’Brien, MD
Nationwide Children’s Hospital


Initial development Name Date
Written by (protocol nurse) Alexis Maciej, MS, RN, CPNP January 23, 2017
Reviewed/approved by (PI) Sarah O’Brien, MD March 24, 2017
Ongoing review
Reviewed and updated by Alexis Maciej MS, RN, CPNP January 23, 2018

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