As cancer treatment continues to evolve, new and different therapies are developed that improve upon the current standard treatments. Many of these new treatments are tested in animals first but then must be proven safe and effective in carefully controlled clinical trials.
Clinical trials are very important, because everything we do now that works was in a clinical trial, and somebody at some point had the benefit of being in that, had the advantage of getting that treatment or whatever is was to make them better. And now it’s become a standard.
The doctor said, ‘We want to put you on a clinical trial." I’ve always heard M. D. Anderson’s famous for...and basically, what it was… they were giving me radiation and chemo at the same time, and the theory behind that was the chemo would enhance the radiation.
Because sarcoma is so rare, there are no large clinical trials with thousands of patients as in the case of the more common cancers like breast, prostate, lung and colon. For sarcoma patients, the trials are fewer with smaller numbers of patients. Clinical trials are conducted in four different phases…each phase is designed to ask specific questions. Phase I trials are the first studies in people, after a treatment has already been tested in animals or in the laboratory. These studies involve a small number of participants…
The objective of the Phase I trial is to try to determine the appropriate dose in human beings. Once you know the appropriate dose and the toxicity profile, then you go to the Phase II setting, when you ask the question, ‘Is it active in sarcoma, breast cancer, lung cancer, colon cancer and the like?'
Phase II trials study how a particular cancer responds to a treatment.
Once you’ve proven that it has this level of activity and yes it is encouraging, then you say in a Phase III setting… then you ask the question, ‘How does it compare to the current standard of care…the new agent versus the old agent… which one of the two is better in the randomized setting?'
Phase III trials usually involve several hundred people and often are conducted in more than one location at a time. Sarcoma studies are usually smaller. Phase IV clinical trials are studies that gather additional information about treatments that already have been approved for use in patients by the FDA.
Some of the studies are being done here only. They are studies that we have particular interest in, often involving collaborations with our supportive care group looking at better ways of delivering more intensive chemotherapy, because we know that more intensive chemotherapy is more effective for the majority of patients.
While many forms of sarcoma remain difficult to treat, there have been some major advances due to clinical trials. For example, the drug, Gleevec, already successful in treating CML, Chronic Myeloid Leukiemia…is also effective in treating GIST…gastrointestinal stromal tumors.
Now we have an incredible advance with the advent of a drug called Imatinib or the trade name is Gleevec, where probably 80% of the patients have marked benefit in a period of days from the initiation of therapy, and so this has gone from being the worst soft tissue sarcoma, that we had to treat… to the best sarcoma that we have to treat, because we can treat it with less toxic treatments which are more effective. But as the knowledge of molecular biology continues, we’re going to find out what the target able abnormalities are, and then we’ll have new targets for drug development, so that we can block those abnormalities and get specific treatments.
Clinical trials are not appropriate or available for all patients. It’s important to remember that patient safety and what’s in the best interest of the patient, is what determines the best treatment…and that may not be a clinical trial.
There are other issues wherein the patient may come in with some limited information that might have led one to believe that this clinical trial would be appropriate, but when we actually see the patient, we may feel that a retrial of one of the older drugs at a higher dose may clearly be in the patient’s better interest, and so then even though they may technically be eligible for a clinical trial, we may recommend that there’s something else that may be more appropriate for you. In the interest of patient safety, these trials are more often than not designed in some fairly stringent ways, and the intent behind that indeed is patient safety… that is… we don’t know that drug “x” is clearly going to help a given patient; the last thing we want to do is hurt the patient in the process of helping. All of us took this oath when we got out of medical school that says, 'Above all, do no harm.’ So that’s the primary intent behind the so-called restrictive criteria on clinical trials.
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