This is post no. 2 under the main topic.
| 05-02-2015, 04:03 AM
Clinical trials are studies to find out whether the drug is safe and effective for people. They may be patients with a disease, or healthy people wanting to contribute to the advancement of medical knowledge. Although early medical experimentation was often performed, the use of a control group to provide an accurate comparison for the demonstration of the intervention's efficacy, was generally lacking. For instance, Lady Mary Wortley Montagu, who campaigned for the introduction of inoculation (then called variolation) to prevent smallpox, arranged for seven prisoners who had been sentenced to death to undergo variolation in exchange for their life. Although they survived and did not contract smallpox, there was no control group to assess whether this result was due to the inoculation or some other factor (1). Similar experiments performed by Edward Jenner over his smallpox vaccine were equally conceptually flawed.Thefirst clinical trial was conducted by the physician James Lind. The disease scurvy, now known to be caused by a Vitamin C deficiency, would often have terrible effects on the welfare of the crew of long distance voyages (2). In 1740, the catastrophic result of Anson's circumnavigation attracted much attention in Europe; out of 1900 men, 1400 had died, most of them allegedly from having contracted scurvy. John Woodall, an English military surgeon of the British East India Company, had recommended the consumption of citrus fruit from the 17th century, but their use did not become widespread.The potential treatments identified to have therapeutic potential in the Basic Research stage are then tested in animals for their ability to be delivered to the target organ and tissue to determine how well they are cleared from the system, and to determine their toxicity, safety, and effectiveness. Several potential treatments that do not pass certain tests may be dropped at this stage since they may seem too risky for further development for use in patients (3). The development of new pharmaceutical drugs is essential in order to improve the quality of drug.Clinical trials may be costly, depending on a number of factors. The sponsor may be governmental organization or apharmaceutical, biotech or medical company. Certain functions necessary to the trial, such as monitoring.may be managed by contract research organization or a central laboratory.Clinical trials haveaimportant role in drug development.Clinical trials are experiments done in clinical research. Such biomedical or behavioral research (4,5). on human and animals participants are designed to answer specific questions about biomedical or behavioral interventions, including new treatments as novel vaccines, drugs and medical devicesand known interventions that warrant further study and comparison. Clinical trials generate data on efficacy and safety (6) . They are possible only after they have received health authority committee approval in the country. There are two goals to testing medical treatments: to learn whether they work well enough, called effectiveness and to learn whether they are safe enough, called safety". Neither is an absolute criterion; both safety and efficacy are evaluated relative to how the treatment is intended to be used, what other treatments are available, and the severity of the disease or condition. The benefits must outweigh the risks (7). In the US, the elderly constitute only 14% of the population, while they consume over one-third of drugs. People over 55 (or a similar cutoff age) are often excluded from trials because their greater health issues and drug use complicate data interpretation, and because they have different physiological capacity than younger people(8). Women, children and people with unrelated medical conditions are also frequently excluded. For women, a major reason for exclusion is the possibility of pregnancy and the unknown risks to the fetus.
What is clinical research
Clinical trials are conducted to collect data regarding the efficacy and safety for new drug development. Several stages of approval in the clinical trials process before a drug or device can be sold in the consumer market, if ever.Drug testing begins with extensive laboratory research which can involve many years of experiments on animals and human. If the laboratory research is successful, researches send the data for approval to continue research and testing in humans.
Once approved, human testing of experimental drugs can begin and is typically conducted in different phases. Each phase is considered a unique trial and, after completion of a phase, investigators are required to submit for approval.
Human Clinical Trial Phases:
Phase I Thisstarting phase of drug testing, which can take many months to complete, usually includes a some small number of healthy volunteers (20 to 100), who are generally paid for participating in the study. The study is designed to determine the effects of the drug or device on humans including how it is metabolized, and excreted. This phase also investigates the side effects that occur as dosage levels are increased. About 70% of experimental drugs pass this phase of testing.
Phase II studies test the efficacy of a drug.. This 2ndphase of testing may last from several months to 2 years, and involves up to several hundred patients. Most phase 2ndstudies are randomized trials where one group of patients receives the experimental drug, while a second "control" group receives a standard treatment. Often studies are "blinded" which means that neither the patients nor the researchers received the experimental drug. This allows investigators to provide the pharmaceutical company. About one-third of experimental drugs successfully complete both Phase I and Phase II studies.
Phase III studies involve randomized and blind testing in many hundred to many thousand patients. This large-scale testing, which may last many years, provides the pharmaceutical company with a more thorough understanding of the effectiveness of the drug.the benefits and the range of possible adverse reactions. 80.5% to 90.2% of drugs that enter Phase 3rdstudies successfully complete.. Once Phase 3rdis complete, a pharmaceutical company can request approval for marketing the drug.
Phase IV is called Post Marketing Surveillance Trials, is conducted after a drug. has been approved for consumer sale. Pharmaceutical companies have several objectives at this stage: 1. to compare a drug with other drugs already in the market; 2. to monitor a drugs long-term effectiveness and impact on a patients quality of life; and 3 to determine the cost-effectiveness of a drug therapy relative to other traditional and new therapies. Phase IV studies can result in a drug.
The role of clinical trials in drug approvals
• Pre-clinical studies
• Clinical trials
• Regulatory product submission
• Submission review
• Market authorization decision
• Public access
• Surveillance, inspection, and investigation
• The post-market part of the process begins with surveillance, inspection, and investigation when a drug has been made accessible to the public.
Potential benefits Clinical Trials:
When we take part in a clinical trial, we help others by advancing medical research. If we have a disease, there could be personal benefits.
• we may get early access to a new promising treatment.
• The treatment may cure or control our condition. Even if we are not cured, our quality of life might improve.
• We may get additional access to expert health because of the time we will spend with the research team involved in this study.
Potential risks Clinical Trials:
If clinical trial is to get access to a new treatment, be aware that this may not happen. Clinical trials often compare a new drug to:
• an approved drug that is already on the market
• a placebo a dummy treatment with no active ingredients
In many cases, people are not told which treatment they are getting in order to generate unbiased results. Even if we get the new drug. It might be less effective than a treatment we were using before the trial. There is also a risk of serious side effects (short-term and long-term) as the safety profile of an investigational drug is not as well understood as an approved drug.A clinical trial can take up a lot of your time for things like travel, tests and even hospital stays.
Responsibility for the safety of the subjects in a clinical trial is shared between the sponsor, the local site investigators the various IRBs that supervise the study, and the regulatory agency for the country where the drug or device will be sold.For safety reasons, severclinical trials of drugs are designed to women of childbearing age, pregnant women, and women who become pregnant during the study. Some cases, the male partners of these women are also required to take birth control.Once a drug has been approved, how is it monitored.Once a drug is on the market, regulatory controls. The distributor of the drug must report new information received serious side effects including failure of the drug to produce the desired effect. The distributor studies that have provided new safety information and request approval for any major changes to the manufacturing processes, dose regime or recommended uses for the drug.
A clinical trial is an organized research study designed to investigate new methods of preventing, detecting, diagnosing, or treating an illness or disease, such as cancer. In some instances, clinical trials attempt to improve quality of life. When studying cancer treatment, researchers generally attempt to determine whether a new method of treatment is superior to the standardtrials are extremely important in discovering new techniques to disease. For example, many of the advances in breast cancer detection and treatment resulted from clinical trials.Clinical trials are a type of research study to explore whether a medical treatment, drug, strategy or device is safe and effective for human use. The purpose of clinical trials is research, so the studies follow strict scientific standards. These standards protect patients and help produce reliable study results.
1. "Clinical Trials" (PDF). Bill and Melinda Gates Foundation. Retrieved January 2014.
2. J Med Invest. 2006 Aug;53(3-4):292-6. Clinical trials for drug approval: a pilot study of the view of doctors at Tokushima University Hospital.Yanagawa H1, Nishiya M, Miyamoto T, Shikishima M, Imura M, Nakanishi R, Ariuchi K, Akaishi A, TakaiS, Abe S, Kisyuku M, Kageyama C, Sato C, Yamagami M, Urakawa N, Sone S, Irahara M.
3. Young, Susan. "Foundation Medicine Joins Coalition Aiming to Shake Up Cancer Drug Trials | MIT Technology Review". Technologyreview.com. Retrieved 2013-11-14.
4. "Adaptive Clinical Trials for Overcoming Research Challenges". News-medical.net. Retrieved 2014-01-04.
5. Pharmabiz.com, 19 May 2014, Mumbai ISCR releases Guide for clinical trial participants on International Clinical Trials Day(Accessed on 20th May 2014)
6. Young, Susan. "Foundation Medicine Joins Coalition Aiming to Shake Up Cancer Drug Trials | MIT Technology Review". Technologyreview.com. Retrieved 2013-11-14.
7. Rennan, Zachary (2013-06-05). "CROs Slowly Shifting to Adaptive Clinical Trial Designs". Outsourcing-pharma.com. Retrieved 2014-01-05.
Department of Botany
R.B.S. College, Agra.