New research: personalised chemotherapy based on your DNA
Dutch scientists have recently studied the effects of preventive screening of patients for their genetic sensitivity to the drugs capecitabine and fluorouracil. Capecitabine in particular is widely used for chemotherapy treatments. But what exactly does this drug do? What does your DNA have to do with the way you respond to it? And are we heading towards personalised chemotherapy based on your genes?
What is capecitabine?
Chemotherapy uses cytostatics; medicines that slow down cell growth and cell division. One of these drugs is capecitabine. This drug is used in the treatment of bowel cancer, stomach cancer and breast cancer. Capecitabine is a so-called prodrug of fluorouracil (5-FU). This means that capecitabine is converted into fluorouracil in the body, which is, incidentally, sometimes also used directly as a medicine against cancer.
What is the problem with capecitabine?
Although most people respond to it normally, some patients experience serious side effects from a standard dose of capecitabine. It even happens that people die as a result.
What does your DNA have to do with the way you respond to capecitabine?
Capecitabine is processed by the enzyme DPD, which is involved in the breakdown of medicines from the fluoropyrimidine group (to be precise, DPD is responsible for more than 80% of the processing of these medicines). If this enzyme’s activity is reduced, capecitabine can have toxic effects. An abnormality in the DPYD gene, which codes for the enzyme, can therefore have a strong influence on the way your body responds to capecitabine. This abnormality occurs in 5 to 8% of people.
Research into personalised dosing
Scientists in seventeen Dutch hospitals recently studied the effect of a personalised dose of fluoropyrimidine medicines, such as capecitabine, on patient safety. Patients were first screened for the four most relevant variants of the DYPD gene. Some of the patients for whom, on the basis of their genes, you would expect a high chance of side effects were then given a 25% or 50% lower dose. And what turned out? Patients given a reduced dose did indeed suffer fewer side effects than the group given a standard dose. One of the researchers’ recommendations was therefore to make medicine dosing based on your genes the new standard of care.
iGene and personalised medication: pharmacogenetic passport
Want to know about your own sensitivity to capecitabine, fluorouracil and all kinds of other medicines? Order an iGene DNA test! In addition to information about your predisposition to various conditions, you then also receive an extensive pharmacogenetic passport based on your own DNA.