Dr. Ogbru received his Doctorate in Pharmacy from the University of the Pacific School of Pharmacy in 1995. He completed a Pharmacy Practice Residency at the University of Arizona/University Medical Center in 1996. He was a Professor of Pharmacy Practice and a Regional Clerkship Coordinator for the University of the Pacific School of Pharmacy from 1996-99.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
DRUG CLASS AND MECHANISM: Imatinib is an oral medication used for treating
chronic myeloid leukemia and acute lymphoblastic leukemia. It is classified as a
kinase inhibitor. Kinase inhibitors include dasatinib (Sprycel), erlotinib
(Tarceva), gefitinib (Iressa),
nilotinib (Tasigna), pazopanib (Votrient),
sunitinib (Sutent), and vandetanib (Caprelsa). Kinase inhibitors prevent tumors
from growing by reducing the action of proteins that control cell division,
growth and survival. These proteins are usually present in larger quantities or
are more active in cancer cells. By reducing the activity of these proteins,
growth and survival of cancer cells are reduced. The FDA approved imatinib in
April 2003.
PRESCRIPTION: Yes
GENERIC AVAILABLE: Yes
PREPARATIONS: Tablets: 100, and 400 mg
STORAGE: Imatinib should be stored at room temperature between 15-30 C (59-86
F).
PRESCRIBED FOR: Imatinib is used for the treatment of adult and pediatric
patients with newly diagnosed Philadelphia chromosome positive, chronic myeloid
leukemia (Ph+ CML); treatment of Ph+ CML after failure of interferon-alpha
therapy; adults with relapsed or refractory Philadelphia chromosome positive
acute lymphoblastic leukemia (Ph+ ALL); adults with myeloproliferative or
myelodysplastic diseases; mastocytosis; hypereosinophilic syndrome (HES) and/or
chronic eosinophilic leukemia (CEL); dermatofibrosarcoma protuberans; and
gastrointestinal stromal tumors (GIST)
DOSING: The recommended dose range is 300-800 mg orally daily depending on
the condition being treated. All doses should be administered with a meal and a
large glass of water. A dose of 800 mg should be administered as 400 mg twice
daily. Doses less than 800 mg may be administered once daily. It can be
dissolved in apple juice or water for those with difficulty swallowing.
DRUG INTERACTIONS: The blood concentration of imatinib may be increased by
several drugs that reduce its break down by the liver. Examples include
ketoconazole, itraconazole (Sporanox), clarithromycin (Biaxin), atazanavir (Reyataz),
indinavir (Crixivan), nelfinavir (Viracept), ritonavir (Norvir), saquinavir (Invirase),
telithromycin (Ketek), voriconazole (Vfend), and grapefruit juice.
Increased blood concentrations of imatinib may increase the occurrence of
adverse effects.
Certain drugs decrease the blood concentration of imatinib resulting in
decreased blood levels and possibly reduced effect. Examples include
carbamazepine, phenobarbital, rifampin, phenytoin, fosphenytoin, primidone, and
St John's Wort.
Imatinib increases the blood concentration of simvastatin (Zocor) by reducing
the activity of enzymes that break down simvastatin in the liver. This may
increase the side effects of simvastatin. Imatinib may interact with other drugs
that are broken down in a similar way as simvastatin.
PREGNANCY: Imatinib is harmful to the fetus and should not be used during
pregnancy.
NURSING MOTHERS: Imatinib is excreted in human milk; therefore, nursing
mothers should either discontinue imatinib or stop
breastfeeding.
Leukemia is a type of cancer of the blood cells in which the growth and development of the blood cells are abnormal. Strictly speaking, leukemia should refer only to cancer of the white blood cells (the leukocytes) but in practice it can apply to malignancy of any cellular element in the blood or bone marrow, as in red cell leukemia (erythroleukemia).
Childhood acute lymphoblastic leukemia is the most common type of cancer in children. Symptoms and signs include fever, easy bruising, bone or joint pain, weakness, loss of appetite, and painless lumps in the neck, underarm, stomach, or groin. Treatment depends upon staging and may include chemotherapy, radiation, or stem cell transplant.
While the exact cause(s) of leukemia is not known,
risk factors have been identified.
Leukemias are grouped by how quickly the disease
develops (acute or chronic) as well as by the type of blood cell that is
affected (lymphocytes or myelocytes). The four main types of leukemia include acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), acute myelocytic leukemia (AML), and chronic myelocytic leukemia (CML).
People with leukemia are at significantly increased
risk for developing infections, anemia, and bleeding. Other symptoms and signs include easy bruising, weight loss, night sweats, and unexplained
fevers.
The diagnosis of leukemia is supported by findings of the
medical history and examination, and examining blood
and bone marrow samples under a microscope.