Chronic myelogenous leukemia (CML) is one of the four most common types of leukemia and is responsible for 15 to 20 percent of all adult leukemia’s. CML is a deadly cancer of the bone marrow cells that causes white blood cells to increase to more than twelve times their limit, at an uncontrollable rate. Normally, this can lead to fatigue, fever, and a fatal 5-year survival rate.Novartis Oncology Pharmaceuticals, the second largest drug company in the world, with headquarters in Switzerland, is the main company investigating a new drug to cure CML, called STI-571 (Gleevec). This drug has taken on many names such as Glivec, Imatinib Mesylate, CGP57148B, but due to nomenclature issues with the F.D.A., the drug is now named Gleevec.
Novartis’ primary goal of their studies was to discover an ability to treat cancer by eliminating only the cancer cells with minimal or no effects on normal cells. From many years of research, doctors have successfully created the drug Gleevec, which does just that. Gleevec selectively blocks mutant enzymes that cause CML without harming its molecular correspondents.Gleevec has been put into the class of “cytostatics.” Cytostatics are designed to focus in on cancer cells without harming healthy ones. This is significantly more effective when compared to the normal treatments of leukemia such as radiation and bone marrow transplant.Specifically, Gleevec disrupts the Abelson kinase (Abl) from its accidental activation. This then leads to CML by activating other proteins by adding phosphate to them in a process called phosphorylation. Kinase plays an important role in regulating cell growth and division. Gleevec inactivates the Abelson kinase by binding to it, thus inhibiting it to reproduce. Gleevec works by blocking signals within cancer cells that contain Abl and prevents a series of chemical reactions that cause or signal the cell to grow and divide.With these results, doctors agree that with these same ideas, the pill can be adapted to cure various types of other cancers. Gleevec has already been used in clinical trials to cure certain types of brain and stomach cancers.Gleevec is still at a relatively early phase of clinical testing and has recently been submitted to the F.D.A. for further tests to determine its effectiveness on February 27, 2001. According to the F.D.A., approval for Gleevec can take up to six months before it is available on the market for patients. If approved, it will represent the first drug of its kind that is designated to target specific molecular defects in the leukemia cells without harming the normal cells. According to numerous scientists, the outlook of Gleevec looks promising.Because the pill Gleevec is still at a relatively early phase, the exact dangers associated with the drug have not been fully determined. The only dangers that have been determined are the side effects from numerous clinical trials with Gleevec on many patients. These adverse effects range from nausea to liver toxicity and show no dose limit related dangers, with a little more than ten percent of the patients experiencing mild side effects, while fewer than three percent experienced serious side effects.Although, some scientists have mentioned that if patients need to stay on the drug for years, toxicities oreven drug resistance problems, not seen yet, could develop. Gleevec is also currently being used in trials to determine the contradictions and in-compatibility.The mild adverse effects that have been determined are nausea, vomiting, edema, myalgia, diarrhea, rash, fatigue, anorexia, dyspepsia, thrombocytopenia, neutropenia, and arthralgias. Below are charts that state the specific degrees of these adverse effects associated with different dosages of Gleevec over specific time periods.