17 July 2007
Medicos Mull Advantageous Drug-Food Interactions
by Kate Melville
Exploiting interactions between food and drugs could dramatically lower the rising costs associated with anticancer drugs and other medications, say two oncologists in the Journal of Clinical Oncology. Such interactions are usually considered to be detrimental, but University of Chicago oncologists Mark Ratain and Ezra Cohen pooh-pooh that idea, instead saying that recent studies show that certain foods can beneficially - and dramatically - alter the take-up of anti-cancer drugs.
Ratain and Cohen's comments were inspired by a study that showed that taking the breast cancer drug lapatinib (marketed as TYKERB) with food - instead of on an empty stomach as suggested on the label - resulted in more of the drug being absorbed and available to treat the cancer. They suggest that results like this should point researchers toward novel ways to decrease medication costs while increasing benefits from these expensive drugs.
The study found that taking lapatinib with a meal increased the bioavailability of the drug by 167 percent. Astonishingly, taking the drug with a high-fat meal boosted levels by 325 percent. "Simply by taking this medication with a meal instead of on an empty stomach, we could potentially use [only] 40 percent of the drug," said Ratain. "Since lapatinib costs about US$2,900 a month, this could save each patient US$1,740 or more a month."
Raitan added that topping off a meal with grapefruit juice (which increases plasma concentrations) could increase the savings to 80 percent. "We expect the one 250 mg lapatinib pill accompanied by food and washed down with a glass of grapefruit juice may yield plasma concentrations comparable to five 250 mg pills on an empty stomach," Ratain explained.
The researchers are currently investigating the combination of the drug sirolimus (rapamycin) taken with grapefruit juice, which contains substances that delay the breakdown of many drugs. They believe that dozens, or even hundreds, of drugs ought to be studied in this way. "If we understood the relationship between, say, grapefruit juice and common drugs, such as statins, which taken daily by millions of people to prevent heart disease, we could save a fortune in drug costs," Cohen said. "And patients would get some vitamin C to boot."
Source: University of Chicago Medical Center