Cancer drug test promises safer and more effective clinical trials
To date most of the evidence for drug metabolism and toxicity tests have used normal tissue sections of organs like the liver, kidneys and lungs. The new test was created specifically for oncology drug testing and use in tumor tissue of patients with colorectal and lung cancer.
A major problem in drug development today is the inability to extrapolate the response in preclinical models of cell patients. “Approximately 90% of clinical trials fail because the drugs used are too ineffective or too toxic,” said Dr. Schooner. “This not only involve unacceptably high costs of drug development, it also exposes patients to risks of toxicity or simply waste their time on tests of a substance that turns out to be ineffective.”
The problem arises from the fact that individual patients respond to drugs. In addition, each tumor consists of a variety of different cancer cells that interact in different ways with individuals under non-tumor cells, resulting in highly variable growth behavior and response to drugs. Dr. Schooner and his team set about trying to develop a drug test to eliminate these problems and provide a precise model of the response of each patient.
“Based on fresh tissue culture intact surgically treated cancer patients are now able to analyze many tumors of different patients, to identify differences in drug response among patients, and to understand variations in response subtypes within a tumor cell, “said Dr. Schooner.
The new test allows scientists to translate the results of commonly used cell lines in a preclinical model that is as close as possible to the use of the same drug in the clinical setting, allowing a better estimate of the number of patients that can respond to treatment. It also helps to identify biomarkers that can predict drug response for patients entering a clinical trial, allowing researchers to include only those patients whose participation will give a meaningful response to the question.
“Along with all patient clinical data and analytical testing various systems such as analysis of signaling pathways, we were able to characterize individual tumors in more detail. This will improve the understanding of the effects of drugs and treatments, a step forward towards the goal of individualized cancer therapy, “he said. “The test is of particular interest to pharmaceutical companies because it allows the analysis of samples from a significant number of patients with different tumors in a short period of time, and can therefore accelerate the progression of a potential new treatment for clinical trials.
It can help to gain more knowledge about the mode of action of a new compound in patients, the disease and to identify optimal areas, for example, tumors with mutations in particular or over-expression of target receptors, and dose.
To date, the test has been validated only in the colon, non-small cell lung, and breast cancer tumors, but no reason to think that it would be equally accurate for other types of solid tumors, say scientists. “Given that evidence allows us to keep the complex environment of primary cancer tumor, we believe holds great promise for rapid and efficient clearing of response to cancer drugs,” said Dr. Schooner. “We hope to be able to apply to an increasing number of drugs emerging from the laboratories of pharmaceutical companies to help shorten development time and make clinical trials much more efficient and safer for patients.”