It is here but evolving slower than what all of us might like to see, and in many areas it is still so much of a “Science” but as developments occur through biotech we are seeing some amazing results. There’s also the bridging of the gap with bringing genomics to the point of care, as physicians and patients alike are still in the dark on the topic. R and D costs are high and much of it has been or is going to be 
outsourced outside of the US, and the treatment plans are not affordable in many areas.
Personalized medicine will continue to grow with breakthroughs and the challenge is to educate, bring to the point of care, and hopefully make the treatment plans affordable and covered by insurance plans. The FDA today is also working on gathering needed information to hopefully approve and get viable products to the market place, but in the war on cancer, it is simply something that can’t be overlooked and technology breakthroughs and studies appear every day on how information is helping to create a world of medicine that can be customized to work for the individual, not the masses, in a way that will help remove the trial and error processes as time goes on. It will take a joint effort from many entities to make this work. BD
The one thing Kevin Carlberg refused to face after his diagnosis with brain cancer in 2002 was anyone's estimate for how long he might live. His doctors and his family all knew the number: six to 18 months. "I understand the averages," says Carlberg, a rock musician who had just released a CD and was two months from his wedding date when he was told he had the worst stage of the worst kind of brain cancer, glioblastoma. "But every person is different." Those words could serve as a new mantra in medicine. After having his tumor removed and undergoing chemotherapy and radiation, Carlberg received a novel treatment that was designed using his own white blood cells and proteins taken from his tumor to prod his immune system into recognizing and attacking more cancer. It's an example of a growing health-care strategy known as personalized medicine.
Personalized medicine aims to minimize that one-size-fits-all model by matching each patient to a specific treatment based on the genetic and molecular characteristics of that person's tumor. Doctors can use genetic information gleaned from the tumor itself to choose — or avoid — certain medications for that patient or, as in Carlberg's case, create a treatment specifically for that person.
To identify these sub-types of cancer, doctors search for biomarkers, molecular indicators of how that tumor will respond to various drugs. Slamon, for example, worked for more than a decade trying to understand a protein biomarker called HER2.
Nonetheless, after a slow start, the field of personalized medicine is gathering steam as researchers and drug companies focus more on drugs to target subsets of patients instead of blockbuster medications aimed at treating all of them. According to the research company Datamonitor, sales of targeted cancer therapies grew 33 percent worldwide last year. Since 2005, 10 targeted drugs have come on the market.
Slamon spent years trying to persuade others that targeting HER2 would cure some women of breast cancer. Eventually, the drug company Genentech developed Herceptin.
"Drug development is becoming more complex and more challenging as we understand more," Slamon says. "But that is how it has to be if we're going to treat cancer more effectively."
SouthCoastToday.com: Getting personal with cancer therapy
Personalized Cancer Medicine Is Here, NOW!
ReplyDeleteAs we enter the era of "personalized" medicine, it is time to take a fresh look at how we evaluate treatments for cancer patients. More emphasis is needed matching treatment to the patient. Patients would certainly have a better chance of success had their cancer been chemo-sensitive rather than chemo-resistant, where it is more apparent that chemotherapy improves the survival of patients, and where identifying the most effective chemotherapy would be more likely to improve survival.
Findings presented at the Annual Meeting of the European Society for Clinical Investigation in Uppsala, Sweden and the Annual Meeting of the American Assoication for Cancer Research (AACR) in San Diego, CA concluded that "functional profiling" with cell-based assays is relevant for the study of both "conventional" and "targeted" anti-neoplastic drug agents (anti-tumor and anti-angiogenic activity) in primary cultures of "fresh" human tumors.
Cell-based Assays with "cell-death" endpoints can show disease-specific drug activity, are useful clinical and research tools for "conventional" and "targeted" drugs, and provide unique information complementary to that provided by "molecular" tests. There have been more than 25 peer-reviewed publications showing significant correlations between cell-death assay results and patient response and survival.
Many patients are treated not only with a "targeted" therapy drug like Tarceva, Avastin, or Iressa, but with a combination of chemotherapy drugs. Therefore, existing DNA or RNA sequences or expression of individual proteins often examine only one compenent of a much larger, interactive process. The oncologist might need to administer several chemotherapy drugs at varying doses because tumor cells express survival factors with a wide degree of individual cell variability.
There is a tactic of using biopsied cells to predict which cancer treatments will work best for the patient, by taking pieces of live "fresh" tumor tissue, applying different chemotherapy treatments to it, and examining the results to see which drug or combination of drugs does the best job killing the tumor cells. A cell-based assay test with "functional profiling," using a cell-death endpoint, can help see what treatments will not have the best opportunity of being successful (resistant) and identify drugs that have the best opportunity of being successful (sensitive).
Funtional profiling measures the response of the tumor cells to drug exposure. Following this exposure, they measure both cell metabolism and cell morphology. The integrated effect of the drugs on the whole cell, resulting in a cellular response to the drug, measuring the interaction of the entire genome. No matter which genes are being affected, functional profiling is measuring them through the surrogate of measuring if the cell is alive or dead.
For example, the epidermal growth factor receptor (EGFR) is a protein on the surface of a cell. EGFR-inhibiting drugs certainly do target specific genes, but even knowing what genes the drugs target doesn't tell you the whole story. Both Iressa and Tarceva target EGFR protein-tyrosine kinases. But all the EGFR mutation or amplificaton studies can tell us is whether or not the cells are potentially susceptible to this mechanism of attack. They don't tell you if Iressa is better or worse than Tarceva or other drugs which may target this. There are differences. The drugs have to get inside the cells in order to target anything. So, in different tumors, either Iressa or Tarceva might get in better or worse than the other. And the drugs may also be inactivated at different rates, also contributing to sensitivity versus resistance.
As an example of this testing, researchers have tested how well a pancreatic cancer patient can be treated successfully with a combination of drugs commonly used to fight lung, pancreatic, breast, and colorectal cancers. The pre-test can report prospectively to a physician specifically which chemotherapy agent would benefit a cancer patient. Drug sensitivity profiles differ significantly among cancer patients even when diagnosed with the same cancer.
The funtional profiling technique makes the statistically significant association between prospectively reported test results and patient survival. It can correlate test results that are obtained in the lab and reported to physicians prior to patient treatment, with significantly longer or shorter overall patient survival depending upon whether the drug was found to be effective or ineffective at killing the patient's tumor cells in the laboratory.
This could help solve the problem of knowing which patients can tolerate costly new treatments and their harmful side effects. These "smart" drugs are a really exciting element of cancer medicine, but do not work for everyone, and a pre-test to determine the efficacy of these drugs in a patient could be the first crucial step in personalizing treatment to the individual.
Literature Citation:
Functional profiling with cell culture-based assays for kinase and anti-angiogenic agents Eur J Clin Invest 37 (suppl. 1):60, 2007
Functional Profiling of Human Tumors in Primary Culture: A Platform for Drug Discovery and Therapy Selection (AACR: Apr 2008-AB-1546)
Thank you very much for the detailed comment here and all the information contained.
ReplyDeleteBeing I post on the subject, the new breakthroughs I see in my feeds are almost daily, and many are lifesaving as well. It will be a challenge getting clinical and personalized together at the physician's office, but it will get there.
Personalized medicine can really help nail down what will and what won't work for us, as shown with the HER test and now Warfarin as well. We have a lot more knowledge and anticipated outcome information up front for sure!