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Sickle Cell Diseases

Effectiveness of Hydroxyurea and Magnesium Pidolate Alone and in Combination in Hemoglobin SC Disease: A Phase II Trial

What is the purpose of this study?

This research study is being done to see if taking hydroxyurea, magnesium (Mg) pidolate (a form of magnesium that is better tolerated than other forms of magnesium), or both of these drugs together has a beneficial effect on hemoglobin SC disease (HbSC) and if it is safe to take the drug(s) for an extended time period. Hydroxyurea is approved for the treatment of HbSS disease (homozygous sickle cell disease or sickle cell anemia) but not HbSC disease. Magnesium pidolate is not approved for the treatment of either type of sickle cell disease (HbSS or HbSC); therefore, this treatment is investigational. Because there is relatively little information about treatment with Mg in Hb SC disease patients, the first 40 patients enrolled in this study will be taking part in a "Safety Pilot." The Safety Pilot part of the study will look for any unexpected side effects from Mg.

Who will be included in this study?

You are being asked to take part in a clinical research study because you have sickle cell disease (HbSC), and you are at least 5 years old.

What is involved?

There are 16 visits required for this study. Participation in the study will last about 12 months (one year). This includes some testing in the week prior to the beginning of treatment, 11 months of treatment, and a follow-up visit after subjects have been off of the study drugs for one month.

Before the treatment begins (Visit 1 - Screening Visit):

  • A medical history (including permission to review medical records to determine eligibility to continue participation in the study)
  • A physical exam
  • A blood sample (about 2 teaspoons) will be collected for lab tests, which will include blood counts, a chemistry panel, and an HIV test
  • An additional blood sample (about 4 teaspoons) will be collected at this visit
  • Part of one blood sample will be used for a DNA test of "alpha globin genes" in order to find out if the number of these genes has an effect on the response to treatment
  • A pregnancy test will be done on all female patients of childbearing potential. The result of the pregnancy test must be negative to be eligible to participate in this research study

Randomization Visit (Visit 2 - Baseline):

  • A physical exam
  • A blood sample (about 2 teaspoons) will be collected for lab tests to see the pre-treatment results of the complete blood count and chemistry panel
  • An additional blood sample (about 4 teaspoons) will be collected at this visit
  • A urinalysis
  • A pregnancy test will be done on all female patients of childbearing potential

The following will be done every two weeks during the first eight weeks of treatment (Visits 3 - 6):

  • A physical exam
  • A blood sample (about 1 teaspoon) will be collected for lab tests to see if the study drugs are working and safe
    An additional blood sample (about 4 teaspoons) will be collected after the patient has been on the study drugs for 2 months (Visit 6)
  • A pregnancy test will be done on all female patients of childbearing potential at each of these visits 

The following will be done every month for 9 months (Visits 7 - 14):

  • A physical exam
  • A blood sample (about 1 teaspoon) will be collected for lab tests to see if the drugs are working and safe
  • An additional blood sample (about 4 teaspoons) will be collected after the patient has been on the study drug for 4 months and again at 6 months (Visits 8 and 10)
  • A urinalysis will be performed at Month 6 (Visit 10)
    A pregnancy test will be done on all female patients of childbearing potential at each of these visits

The following will be done after 11 months of treatment (Visit 15):

  • A physical exam
  • A blood sample (about 1 teaspoon) will be collected for lab tests to see if the study drugs are working and safe
  • An additional blood sample (about 4 teaspoons) will be collected after the patient has been on the study drugs for 11 months
  • A pregnancy test will be done on all female patients of childbearing potential
  • The study logbook will be collected. No study drug is given at this visit

The following will be done after the patient has been off study drugs for one month (Visit 16):

  • A physical exam
  • A blood sample (about 2 teaspoons) will be collected for lab tests to see if the study drugs are working and safe
  • A urinalysis

What are the benefits?

Subjects who participate in this research study may or may not experience a direct benefit. Regardless of the treatment arm of the study to which subjects are assigned, subjects may benefit from increased monitoring that will occur by participating in this study. The increased frequency of patient and provider contact may provide an opportunity for additional aspects of medical care and psychosocial support that might otherwise have been unrecognized at standard clinic visits, which usually occur every 6 months. The overall goal of this study is that the information learned will benefit research and other people with sickle cell disease in the future.

Will I get all the facts about the study?

Parents interested in having their child participate, as well as adults, will be scheduled with a physician who will explain all of the details of the study. The physician will review the consent form and will be sure that all questions are answered. The consent form goes over all of the procedures, the risks, the benefits, the compensation, who to contact with questions or concerns. Study procedures will not begin until a parent/guardian or adult has signed this consent form. A child of a certain age may need to sign the consent form and/or give his/her verbal agreement.

What are the risks?

A detailed list of side effects will be provided to those patients interested in knowing more about the study.

Who should I contact for more information?

Tamara Nordheim, RN, BSN
Cincinnati Children's Hospital Medical Center
Division of Hematology / Oncology
3333 Burnet Ave
Cincinnati, OH 45229-3039
Phone: 513-636-6770
Sicklecell@cchmc.org