Irinotecan, also known by its brand name Camptosar, is used mainly as a second-line treatment for colorectal cancer. The FDA recommends screening patients for a gene that could make them more susceptible to the harmful side effects of the drug, the most worrisome of which is neutropenia, an abnormally low number of white blood cells.
In a paper published in the Aug. 28, 2007 Journal of the National Cancer Institute, UNC researchers analyzed data from nine previous studies of irinotecan. They found that patients who received a medium or high dose of the drug had greater risk of neutropenia if they had two copies of a variation of the gene UGT1A1, known as UGT1A1*28. At lower doses, however, the risk was the same regardless of what UGT1A1 gene the patients had.
“Many institutions saw the FDA’s recommendation as a mandate to test all patients before treating them with irinotecan even though many clinicians didn’t think it was always necessary given that low doses of the drug weren’t causing problems,” said Howard McLeod, Pharm.D., senior author of the study and director of the UNC Institute for Pharmacogenomics and Individualized Therapy.
“Our review showed that at low doses the drug is well tolerated and can be taken by most people,” McLeod said. “As the dosage increases, genetics become a larger factor in determining what side effects patients experience, and then testing becomes essential.”
Having a genetic test available for a medicine is valuable, but so is knowing when to use that test, said Dr. Richard Goldberg, a co-author of the study and physician in chief of the North Carolina Cancer Hospital.
“There are so many treatment options for cancer patients that the more information we have about matching the right therapy to the patient, the better off we all are,” Goldberg said. “Studies like this one give oncologists the tools needed to take better care of patients while avoiding tests and expenses that aren’t needed.”
The authors recommended that the FDA amend the product information for irinotecan to describe the association between irinotecan dose and risk of hematologic toxicity among patients with two UGT1A1*28 genes.
Clinton Colmenares | EurekAlert!
New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)
Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology
An international team of physicists has monitored the scattering behaviour of electrons in a non-conducting material in real-time. Their insights could be beneficial for radiotherapy.
We can refer to electrons in non-conducting materials as ‘sluggish’. Typically, they remain fixed in a location, deep inside an atomic composite. It is hence...
Two-dimensional magnetic structures are regarded as a promising material for new types of data storage, since the magnetic properties of individual molecular building blocks can be investigated and modified. For the first time, researchers have now produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Swiss Nanoscience Institute at the University of Basel and the Paul Scherrer Institute published their findings in the journal Nature Communications.
Ferrimagnets are composed of two centers which are magnetized at different strengths and point in opposing directions. Two-dimensional, quasi-flat ferrimagnets...
An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday...
In the race to produce a quantum computer, a number of projects are seeking a way to create quantum bits -- or qubits -- that are stable, meaning they are not much affected by changes in their environment. This normally needs highly nonlinear non-dissipative elements capable of functioning at very low temperatures.
In pursuit of this goal, researchers at EPFL's Laboratory of Photonics and Quantum Measurements LPQM (STI/SB), have investigated a nonlinear graphene-based...
Dental plaque and the viscous brown slime in drainpipes are two familiar examples of bacterial biofilms. Removing such bacterial depositions from surfaces is...
23.05.2017 | Event News
22.05.2017 | Event News
17.05.2017 | Event News
23.05.2017 | Physics and Astronomy
23.05.2017 | Life Sciences
23.05.2017 | Medical Engineering