Corporate Banner
Satellite Banner
Technology
Networks
Scientific Communities
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Grapefruit Juice Lets Patients Take Lower Dose of Cancer Drug

Published: Thursday, August 09, 2012
Last Updated: Thursday, August 09, 2012
Bookmark and Share
First cancer study to harness drug-food interaction.

A daily glass of grapefruit juice lets patients derive the same benefits from an anti-cancer drug as they would get from more than three times as much of the drug by itself, according to a new clinical trial.

The combination could help patients avoid side effects associated with high doses of the drug and reduce the cost of the medication.

Researchers at the University of Chicago Medicine study the effects that foods can have on the uptake and elimination of drugs used for cancer treatment.

In a study published in August in Clinical Cancer Research, they show that eight ounces a day of grapefruit juice can slow the body’s metabolism of a drug called sirolimus, which has been approved for transplant patients but may also help many people with cancer.

Patients who drank eight ounces a day of grapefruit juice increased their sirolimus levels by 350 percent.

A drug called ketoconazole that also slows drug metabolism increased sirolimus levels by 500 percent.

“Grapefruit juice, and drugs with a similar mechanism, can significantly increase blood levels of many drugs,” said study director Ezra Cohen, a cancer specialist at the University of Chicago Medicine, “but this has long been considered an overdose hazard. Instead, we wanted to see if grapefruit juice can be used in a controlled fashion to increase the availability and efficacy of sirolimus.”

First study to harness drug-food interaction
Grapefruit juice’s pharmaceutical prowess stems from its ability to inhibit enzymes in the intestine that break down sirolimus and several other drugs.

The effect begins within a few hours of what the researchers refer to as “grapefruit juice administration.” It wears off gradually over a few days.

Cohen and colleagues organized three simultaneous phase-1 trials of sirolimus. Patients received only sirolimus, sirolimus plus ketoconazole, or sirolimus plus grapefruit juice. They enrolled 138 patients with incurable cancer and no known effective therapy.

The first patients started with very low sirolimus doses, but the amounts increased as the study went on, to see how much of the drug was required in each setting to reach targeted levels, so that patients got the greatest anti-cancer effect with the least side effects.

The optimal cancer-fighting dose for those taking sirolimus was about 90 mg per week.

At doses above 45 mg, however, the drug caused serious gastrointestinal problems, such as nausea and diarrhea, so patients taking sirolimus alone switched to 45 mg twice a week.

The optimal doses for the other two groups were much lower. Patients taking sirolimus plus ketoconazole needed only 16 mg per week to maintain the same levels of drug in the blood.

Those taking sirolimus plus grapefruit juice needed between 25 and 35 mg of sirolimus per week.

“This is the first cancer study to harness this drug-food interaction,” the authors note. This study built upon an early clinical trial, which found grapefruit juice boosted anti-cancer effects.

Numerous benefits of grapefruit juice
No patients in the study had a complete response, but about 30 percent of patients in the three trials had stable disease, meaning a period when their cancers did not advance.

One patient receiving grapefruit juice had a partial response-significant tumor shrinkage-that lasted for more than three years.

Although ketoconazole produced a slightly stronger drug-retention effect, grapefruit juice has the advantage that it is non-toxic, with no risk of overdose.

“Therefore,” the authors wrote, “we have at our disposal an agent that can markedly increase bioavailability (in this study by approximately 350 percent) and, critically in the current environment, decrease prescription drug spending on many agents metabolized by P450 enzymes.”

Sirolimus was the first of a series of drugs, known as mTOR inhibitors, that were developed to prevent rejection of transplanted organs but that also have anti-cancer effects.

As the first of its class, it was also the first to come off patent, making it less costly. “Further cost savings,” the authors suggest, could be realized “by combining the drug with agents that inhibit its metabolism.”

Because different people produce varied amounts of the enzymes that break down sirolimus, the effect of grapefruit juice can vary, but tests of enzyme levels may be able to predict how an individual patient will respond.

“The variation in potency of the grapefruit juice itself may be far greater than the variation in the enzymes that break down sirolimus,” Cohen said.

An early version of the study used canned grapefruit juice, generously donated by a Chicago-based grocery chain. But tests of the product found it lacked the active ingredients. So the researchers shifted to a frozen concentrate product supplied by the Florida Department of Citrus.

This study was supported by the National Institutes of Health-and not by a pharmaceutical company.

Dose-finding studies are “not necessarily profitable” for drug makers, the authors note, especially if the study results in lower recommended doses after the drug has been approved and priced.


Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 3,100+ scientific posters on ePosters
  • More Than 4,500+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

New Microbiome Center to Merge Expertise of UChicago, MBL and Argonne
Researchers to study world of microbes across environments.
Wednesday, May 18, 2016
AbbVie, University of Chicago Collaborate
The University of Chicago and AbbVie have entered into a five-year collaboration agreement designed to improve the pace of discovery and advance medical research in oncology at both organizations.
Thursday, April 21, 2016
New Code for Control of Gene Expression
A new cellular signal discovered by a team of scientists at the University of Chicago and Tel Aviv University provides a promising new lever in the control of gene expression.
Thursday, February 18, 2016
Bacterial Circadian Clocks Set by Metabolism, Not Light
New study finds that metabolism is the primary driver of the circadian rhythm.
Monday, December 14, 2015
New Nanomanufacturing Technique Advances Imaging, Biosensing Technology
Researchers invent a novel way to build nanolenses in large arrays using a combination of chemical and lithographic techniques.
Thursday, December 10, 2015
Enormous Genetic Variation May Shield Tumors from Treatment
Debate over Darwinian selection vs. random mutations emerges at the tumor level.
Wednesday, November 11, 2015
Gut Bacteria Can Dramatically Amplify Cancer Immunotherapy
Manipulating microbes maximizes tumor immunity in mice.
Monday, November 09, 2015
Protein Aggregation After Heat Shock Is An Organized, Reversible Response
New study finds protein aggregation after heat exposure is a reversible cellular process, not unrecoverable damage from misfolding.
Friday, September 11, 2015
New Form of DNA Modification May Carry Inheritable Information
Scientists have described the surprising discovery and function of a new DNA modification in insects, worms and algae.
Friday, May 08, 2015
Shape-Shifting Molecule Tricks Viruses Into Mutating Themselves To Death
Study uses two-dimensional infrared spectroscopy to help distinguish between normal and shape-shifted structures.
Thursday, April 16, 2015
Drug-Development Grants Focus On Sleep Apnea, Asthma Research
NIH grants awarded to two University of Chicago research teams will help to develop novel treatments for sleep apnea and asthma.
Tuesday, January 27, 2015
Gut Bacteria that Protect Against Food Allergies Identified
Common gut bacteria prevent sensitization to allergens in a mouse model for peanut allergy, paving the way for probiotic therapies to treat food allergies.
Wednesday, August 27, 2014
Researchers Identify ‘Fat Gene’ Associated with Obesity
Mutations within the gene FTO have been implicated as the strongest genetic determinant of obesity risk in humans, but the mechanism behind this link remained unknown.
Monday, March 17, 2014
Autism and Intellectual Disability Incidence Linked with Environmental Factors
Although autism and intellectual disability have genetic components, environmental causes are thought to play a role.
Monday, March 17, 2014
Staphylococcus Aureus Bacteria Turns Immune System Against Itself
Around 20 percent of all humans are persistently colonized with Staphylococcus aureus bacteria, including the antibiotic-resistant strain MRSA.
Friday, December 13, 2013
Scientific News
The Rise of 3D Cell Culture and in vitro Model Systems for Drug Discovery and Toxicology
An overview of the current technology and the challenges and benefits over 2D cell culture models plus some of the latest advances relating to human health research.
Grant Supports Project To Develop Simple Test To Screen For Cervical Cancer
UCLA Engineering announces funding from Bill and Melinda Gates Foundation.
Injecting New Life into Old Antibiotics
A new fully synthetic way to make a class of antibiotics called macrolides from simple building blocks is set to open up a new front in the fight against antimicrobial drug resistance.
Insight into Bacterial Resilience and Antibiotic Targets
Variant of CRISPR technology paired with computerized imaging reveals essential gene networks in bacteria.
Advancing Protein Visualization
Cryo-EM methods can determine structures of small proteins bound to potential drug candidates.
Alzheimer’s Protein Serves as Natural Antibiotic
Alzheimer's-associated amyloid plaques may be part of natural process to trap microbes, findings suggest new therapeutic strategies.
Slime Mold Reveals Clues to Immune Cells’ Directional Abilities
Study from UC San Diego identifies a protein involved in the directional ability of a slime mold.
How Do You Kill A Malaria Parasite?
Drexel University scientists have discovered an unusual mechanism for how two new antimalarial drugs operate: They give the parasite’s skin a boost in cholesterol, making it unable to traverse the narrow labyrinths of the human bloodstream. The drugs also seem to trick the parasite into reproducing prematurely.
Illuminating Hidden Gene Regulators
New super-resolution technique visualizes important role of short-lived enzyme clusters.
Supressing Intenstinal Analphylaxis in Peanut Allergy
Study from National Jewish Health shows that blockade of histamine receptors suppresses intestinal anaphylaxis in peanut allergy.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
3,100+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,500+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!