|What are clinical trials?
|What is a clinical trial?
When scientists believe based on the available preliminary evidence that they have developed a potentially better way of
treating a disease such as cancer, they must first evaluate how good and safe such treatment actually is in real patients
before it becomes available to the general population. Clinical trials refer to these investigational studies, which evaluate
the safety and efficacy of the latest treatment strategies coming out of the top veterinary research institutions. It is
important to understand that even in human medicine, every new drug and every new treatment must go through clinical
trials first before becoming available. Each trial is designed to answer specific scientific questions, figure out if the new
therapy is safe, what the side effects are, and if it is better than existing treatments in treating cancer. Every clinical trial
should have a protocol (written description) desribing what will be done in the study, how it will be conducted, and why
each part of the study is necessary. The patient, be it human or animal, will be taken out of the study as soon as there
are emerging signs that the new treatment is causing side effects that are too severe and no longer justifiable.
Where do ideas for clinical trials come from?
The ideas for clinical trials often originate in the laboratory. Researchers design a clinical trial protocol (the plan for a
trial) after laboratory studies, including studies on laboratory animals (eg mice or rats) indicate the potential promise of a
new therapy. In veterinary medicine, it is common to perform clinical trials with medicines that already showed benefit in
humans with the same disease.
Why should I enroll my pet in a clinical trial?
If your pet was diagnosed with cancer for which there is no effective treatment or your pet did not respond well to a
traditional treatment, enrolling in a clinical trial may provide you with an option to try new therapies. The treatment is
often available at decreased or no cost to you and even if your pet did not respond to the experimental therapy, its
participation will help pave the way for the development of better and more successful treatment methods in the future. It
is important to remember that you can remove your pet from the trial at any point and are not obligated to keep your pet
on the experimental therapy. There is no penalty and you are the ultimate decision maker whether you want to keep your
pet in the trial or not.
For currently ongoing trials in dogs with cancer, please visit the "Dog Clinical Trials" section.
For currently ongoing trials in cats with cancer, please visit the "Cat Clinical Trials" section.
What are the different types of cancer clinical trials?
There are 4 different cancer clinical trials - prevention, screening, treatment and quality of life.
Treatment clinical trials
Treatment clinical trials test new therapies. These can include a new cancer drug, new surgical procedure, new radiation
therapy protocol, new combinations of treatments, novel treatment methods such as gene therapy, etc.
Prevention clinical trials
Prevention clinical trials test new approaches to prevent or at least slow down the development of cancer. These trials
can be conducted in pets who have never had cancer but may be at increased risk to develop cancer in the future, or to
prevent cancer from coming back in pets who were previously successfully treated. These approaches typically use new
or already existing drugs, vitamins, minerals, or other dietary supplements that doctors believe may lower the risk of a
certain type of cancer.
Screening clinical trials
Screening clinical trials test new ways to detect cancer at its earliest stage when patients have the best chance of cure.
The ultimate goal of successful cancer screening is to be able to conduct a simple test (eg blood test) that will be able to
detect beginning cancer before any symptoms occur.
Quality of Life Clinical Trials
Quality of Life clinical trials (also called Supportive Care clinical trials) test new ways of improving comfort and quality of
life for cancer patients.
What are the phases of clinical trials?
Most clinical trials are conducted in a series of steps called phases. This allows researchers to ask and answer specific
questions in a way that results in reliable information about the drug and protects the patients. Clinical trials are typically
classified into one of the following three phases:
Phase I trials: The primary goals of a Phase I trial are to evaluate safety of the new treatment, how an experimental drug
behaves in the pet's body, figure out the best way to give the new treatment (eg pill or injection), how often, and at what
dose. A phase I trial usually enrolls only a small number of patients and if the treatment appears to be well tolerated,
then it moves to Phase II. However, if the researchers find that the treatment causes significant side effects, then the trial
is discontinued. Sometimes, only one of many pets will experience side effects and in this case, the pet will be removed
from the trial while the others continue.
Phase II trials: A phase II trial continues to test the safety of the treatment and also begins to evaluate how well the new
treatment works in treating a particular type of cancer. If the new treatment continues to be well tolerated by the pets and
there are promising indications that it is successfully treating the cancer in question, then it moves to Phase III.
Phase III trials: A Phase III trial is designed to continue to monitor the safety of the treatment and to truly test how well the
new treatment works compared to an existing standard treatment. Phase III studies typically enroll a large number of pets
who are randomized by chance (not choice) into 2 groups - one group to be treated with the new experimental therapy
and the second group to be treated with what is considered standard medical care for the cancer in question. A
randomized, controlled trial is considered to be the most reliable and impartial method of determining what therapy works
best. The goal of randomization is to produce comparable groups in terms of general participant characteristics, such as
age or gender, and other key factors that affect the probable course the disease would take. In this way, the two groups
are as similar as possible at the start of the study so if one group has a better outcome than the other, the researchers
will be able to conclude with some confidence that the better outcome was due to the treatment rather than the age or
gender of the participants.
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Comprehensive guide to cancer diagnosis and treatment in cats and dogs
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Last updated 4/10/13