People who have been treated with fludarabine will usually be asked to take co-trimoxazole or to use monthly nebulised pentamidine to prevent Pneumocystis jiroveci pneumonia. The profound lymphopenia caused by fludarabine renders patients susceptible to transfusion-associated graft versus host disease, an oftentimes fatal complication of blood transfusion. For this reason, all patients who have ever received fludarabine should only be given irradiated blood components. Fludarabine causes anemia, thrombocytopenia and neutropenia, requiring regular blood count monitoring. Some patients require blood and platelet transfusion, or G-CSF injections to boost neutrophil counts. Fludarabine is associated with the development of severe autoimmune hemolytic anemia in a proportion of patients.Difficulties are often encountered when harvesting peripheral blood stem cells from patients previously treated with fludarabine. Pharmacology
Fludarabine is a purine analog, and can be given both orally and intravenously. Fludarabine inhibits DNA synthesis by interfering with ribonucleotide reductase and DNA polymerase. It is active against both dividing and resting cells. Being phosphorylated, fludarabine is ionized at physiologic pH and is effectually trapped in blood. This provides some level of specificity for blood cells, both cancerous and healthy. History
Fludarabine was produced by John Montgomery and Kathleen Hewson of the Southern Research Institute in 1968. Names
Fludarabine is generally administered as its 5-O-phosphorylated form known as fludarabine phosphate, which is rapidly dephosphorylated to fludarabine in the plasma. References
External links
"Fludarabine". Drug Information Portal. U.S. National Library of Medicine.
Cost, coverage and availability
[US] Oncologists have complained that many patients cannot afford the "astronomical" cost of $138,000 a year, which makes it one of the most expensive drugs in medicine, and [in their view] far more expensive than what is needed to pay the development costs.In 2015 ponatinib is available in England for the treatment of CML (chronic phase, accelerated phase or blast phase) and Ph+ ALL in patients with documented T315I mutation under the Cancer Drugs Fund, and has not been appraised by the National Institute for Health and Care Excellence (NICE), who noted the small expected patient population. NICE estimated that ponatinib would cost approximately £61,000 per year, but the price paid under the Cancer Drugs Fund is confidential and may be different. See also
Bcr-Abl tyrosine-kinase inhibitor, especially the sections on Ponatinib development
 and binding

References
External links
"Ponatinib". Drug Information Portal. U.S. National Library of Medicine.