Chronic myelogenous leukemia typically affects people later in life, at an age when they may be at greater risk of medication-related side effects. Aging bodies don’t necessarily process medications as well, and the situation can be complicated by other medical conditions, such as high blood pressure, diabetes and lung disease.
Having other illnesses doesn’t have an impact on how well you will respond to a CML medication (Saussele and colleagues. Blood 2015;126:42-49). But these conditions may make it more difficult to tolerate drug side effects.
A European study has now looked at whether older people with stable CML are able to take their medication less frequently (Russo and colleagues. Blood Cancer J 2015;5:e347). The people studied were older than age 65 years, and had achieved at least a major molecular response (MMR; a 3-log reduction in BCR-ABL transcripts) while on Gleevec. The study compared people who continued on the standard dose of Gleevec (400 mg once-daily) to people who took Gleevec for one month on/one month off
Over a period of six years, about one-half of the study subjects lost their response. Fortunately, all responded to treatment after re-starting Gleevec, and all were able to re-establish either a complete cytogenetic response (CCyR) or MMR. No one lost control and developed progressive CML.
The researchers noted that an on/off dosing schedule is feasible when necessary, although many people will need to re-start treatment later on. It may be an option for people who need to interrupt therapy, or are having difficulty tolerating side effects. However, it’s important to note that interrupting treatment in this study was only attempted after the person had achieved a good treatment response. It’s also important to mention that dose adjustments should only be done after talking to your hematologist, and with his/her approval. If you do stop your medication, you’ll need to be monitored closely so treatment can be re-started quickly if you run into trouble.