Capecitabine

N ( 4) - pentyloxycarbonyl -5' -deoxy -5- fluorocytidine

L01BC06

Cytostatic

110-121 ° C

Template: Infobox chemical / molecular formula search available

Capecitabine ( Xeloda ® trade name, manufactured by Roche ) is a cytostatic acting drug. Capecitabine is a precursor ( prodrug ) of 5 -fluorouracil, and is converted to the active drug within the tumor. The substance is orally active and is used for treatment of metastatic colorectal cancer, metastatic or locally advanced breast cancer and for palliative treatment of gastric cancer used.

Pharmacokinetics

Capecitabine is a prodrug that is rapidly absorbed from the gastrointestinal tract, with a maximum plasma concentration after 90 minutes. The plasma protein binding is less than 60 %. Capecitabine is hydrolyzed in the liver to 5'- deoxy-5- fluorocytidine, which is converted in cells to 5 -deoxy -5-fluorouridine ( doxifluridine ), and further to the active ingredient 5-fluorouracil (5 -FU).

The efficacy of capecitabine is therefore comparable to 5-FU. The conversion to 5-FU is carried out by the enzyme thymidine phosphorylase which occurs in particularly high concentration in the tumor tissue. By targeting the mechanism of action on tumor cells, the patients tolerated capecitabine rather better and must be treated much less often due to severe side effects.

The reduction of capecitabine and 5 -FU occurs via the enzyme dihydropyrimidine dehydrogenase.

Side effects

Less often than in 5 -FU are particularly nausea, vomiting, and especially stomatitis. Also hair loss is clearly observed less frequently. Nevertheless, it may get severe diarrhea, even under capecitabine. Significantly more likely to occur in the oral medication for hand-foot syndrome. Symptoms range from numbness, tingling and discomfort to severe pain in the palms and soles. It can also lead to ulcers and blisters on the hands or feet. Help sufferers regular cold water baths for hands and feet, or 10% uridine creams. The loss of the fingerprints can not be excluded.

Under therapy with capecitabine, it may very rarely cause serious skin reactions such as Stevens- Johnson syndrome ( SJS) and toxic epidermal necrolysis ( TEN). If there is evidence that treatment must be discontinued permanently and immediately. The manufacturer informed about this risk on 17 December 2013, a Red Hand Letter.

Application

Capecitabine twice daily, morning and evening, taken within 30 minutes after a meal. Depending on the dosage, the patient has to swallow three to seven tablets. In severe side effects, the treatment should be interrupted or the dose reduced.