Clinical trials are research studies realized in humans to response specific questions about biomedical or behavioral interventions on human subjects. These studies evaluating the safety and efficacy of new drugs, vaccines or treatments. Only after a deep study and lots of information, the new intervention is approved to be used as an alternative for a specific disease. This approval are realized by health authorities and ethics committees in the country where approval of the therapy is sought.
Clinical trials frequently involve healthy interventions with no pre-existing medical conditions but sometimes relate to patients with specific health conditions who seek otherwise unavailable treatments. Clinical trials might proceed through five phases that are pilot, phase I, phase II, phase III, and phase IV. The pilot experiment are conducted to gain a better understand of the pharmacologic activities and safety of the product in investigation. Before the pilot, the new molecules are experimented in vitro tests. After that, the pilot is realized in animals.
More than 90% of the substances studied in this phase are eliminated due to be too toxic in humans or don’t show enough pharmacological activity. Usually pilot experiments are conducted to gain insights for design of the clinical trial to follow. The substances with specific pharmacological activity and a toxicity profile acceptable continue to be analyzed in phase I. The phase I clinical trials study is the first group of study in humans. It is compost of a small group of 20 to 100 healthy volunteers who receive financial incentives. During dosing periods, study subjects typically remain under supervision for one to 40 nights.
The purpose of the phase I is to examine the tolerance of the component in healthy people. This phase analyze the highest tolerable dosage, the less effective dosage, the dosage/effect relation, the duration of the effects and the side effects of the drug. With these results are possible to establish a preliminary evolution of the security and the pharmacokinetic profile. Phase II clinical trials, also called as therapeutic pilot study, evaluates the drug or therapeutic intervention in a small group of 100 to 200 patients affect to a determinate disease or pathology condition to determine its efficacy and confirm the security.
Phase III studies investigate the efficacy of the biomedical or behavioral intervention in large groups of at least 800 people through internationals studies, of large scale, in multiples centers, with different population of patients. The objective of this phase is to evaluate the risk/benefit in short and large time of the medicine or therapy by analyzing of the type and profile of the adverse reactions more frequents, such as special characters of the medicament and/or medicinal specialties, for example the relevant clinical interactions, the main factors that modify the effect of the medicines like age, healthy historic and others.
Moreover, it is the phase where the therapeutic profile are established, so it can be analyzed the indications, dosage, administration route, contraindications and side effects. The last phase of clinical trials is the phase IV where studies are conducted after the intervention has been approved for commercialization. These studies are designed to observer effectiveness of the approved intervention in the general population and to collect information about any adverse effects associated with widespread use.
Clinical trials can vary in size, and can involve a single research entity in one country or multiple entities in multiple countries. Elders are frequently barred from trials because their greater health problems and drug use complicate data analysis. Women, children and people with unrelated medical conditions are also frequently excluded. Clinical traits are divided in observational studies and randomized controlled trails. Observational studies observe correlations between the treatment experienced by participants and their health status.
A randomized controlled trial can provide persuasive evidence that the study treatment causes an effect on human health. Nowadays, some Phase 2 and most Phase 3 drug trials are designed as randomized, double-blind, and placebo-controlled. Randomized stand for studies where the subject is randomly assigned to receive either the study treatment or a placebo. Double blind is when neither the researches nor the patients know which treatment they are receiving. Placebo controlled the use of a fake treatment that allows the researchers to isolate the effect of the study treatment from the placebo effect.
A complete series of trials may cost hundreds of millions of dollars. The encumbrance of paying is usually accepted by the sponsor, which may be a governmental organization or a pharmaceutical, biotechnology or medical device company. When the required support exceeds the sponsor’s capacity, the trial may be managed by an outsourced partner, such as a contract research organization or an academic clinical trials unit. EBOLA Ebola is a virus of the _Filoviriade_ family which causes a severe and often fatal hemorrhagic fever in humans and other animals, known as Ebola virus disease.
The virus was first identified in the Democratic Republic of Congo, Africa in 1976. Ebola hemorrhagic fever is a disease caused by one of five different Ebola viruses. Four of the strains can cause severe illness in humans and animals. The fifth, Reston virus, has caused illness in some animals, but not in humans. Ebola is extremely infectious but not extremely contagious. It is infectious, because a microscopic small amount can cause the disease. Instead, Ebola could be considered moderately contagious, because the virus is not transmitted through the air.
Ebola is transmitted through close contact with the blood, secretions, organs or other bodily fluids of infected humans or animals. Also, with surfaces and materials contaminated with these fluids. The Ebola incubation period 2 to 21 days. The first symptoms are the sudden beginning of fever fatigue, muscle pain, headache and painful throat. This is followed by vomiting, diarrhea, symptoms of reduction of kidney and liver function, and in some cases, internal and external hemorrhage.
Ebola virus infections can be diagnosed in a laboratory within a few days after symptoms begin by antibody-capture enzyme-linked immunosorbent assay (ELISA); reverse transcriptase polymerase chain reaction (RT-PCR) assay; IgM ELISA, and virus isolation by cell culture. Later in disease course or after recovery by IgM and IgG antibodies and retrospectively in dead patients by Immunohistochemistry testing; PCR, and Virus isolation by cell culture. However, these test should be realized under maximum biological containment conditions because samples from patients are an extreme risk to human health.
The best form to avoid a contamination are to be awareness to the risks and the practice of protective individuals procedures. There is no longer accepted treatment or vaccine existent to combat the Ebola. Recovery from Ebola depends on good supportive care and the patient’s immune response. People who recover from Ebola infection develop antibodies that last for at least 10 years, possibly longer. It isn’t known if people who recover are immune for life or if they can become infected with a different species of Ebola.
Some people who have recovered from Ebola have developed long-term complications, such as joint and vision problems. The Ebola epidemic have affected multiple countries in Africa, and had a confirmed case in United States. It is considered the largest epidemic in the history. On October,3 the World Health Organization said Ebola had killed more than 3,400 people out of 7,470 confirmed or suspected cases. DEVELOPING OF NEW DRUGS AND CLINICAL TRIALS Ebola has no approved treatment or vaccine existent.
However, basic procedures in early stages of the illness can considerably improve the chances of survival like providing intravenous fluids and balancing body electrolytes, maintaining the homeostasis of oxygen status and blood pressure, and treating other infections if they occur. Due to this epidemic disease has so many cases of contaminations and dead, and a risk of by transmitted by the air because of virus mutations, experimental vaccines and treatments for Ebola are under development, but they have not yet been fully tested for safety or effectiveness.
Medicago is one example of studies which focus in developing vaccines based on proprietary manufacturing technologies and virus-like particles (VLPs). Medicago has entered into a research collaboration agreement with the U. S. Army Medical Research Institute of Infectious Diseases (USAMRIID) for the development of a plant-based VLP vaccine candidate for the prevention of Ebola. Another vaccine are being developing by Johnson & Johnson in collaboration of the National Institute of Health. The National Institutes of Health Clinical Center is testing an experimental Vaccine for prevention of the infection in clinical trials.
The vaccine used in the study contains man-made genetic material similar to one part of the Ebola virus, which is designed to stimulate an immune response to the virus. The vaccine itself cannot cause Ebola virus infection because it does not contain any Ebola virus. Participants are assigned to one of three groups as they enter into the study. Of the first 16 people in the study, 12 receive the lowest study dose of vaccine and 4 receive placebo. If this dose is safe, then of the next 16 people who enter the study, 12 receive a higher dose of the vaccine, and the remaining 4 receive placebo.
If this dose is safe, the final 12 people in the last group of 16 receive the highest study dose, and 4 receive placebo. The vaccine is given as a single injection in the arm on the day of enrollment. Participants keep a diary for 5 days, recording their temperature, symptoms and any reaction at the injection site. They call a study nurse the day after vaccination to report how they feel, and they return to the clinic approximately six times for follow-up evaluations. These visits may include a check of vital signs, physical examination, blood and urine tests, or other medical tests if needed.
This clinical trial is a Phase I, randomized, placebo-controlled, double-blinded study to examine safety, tolerability and immune response of a recombinant Ebola vaccine in healthy adults, and the results still unknown. Many others clinical trials are being developed, however, even though all the studies that are being doing, Ebola virus still does not have a medicine or vaccine that can stop it to become a pandemic.
BIBLIOGRAPHY Peters, C. J (1999). An Introduction to Ebola: The Virus and the Disease. J Infect Dis. P. 179 Carlisle, R. (2004). Scientific American Inventions and Discoveries, John Wiley & Songs, Inc. , p. 393. Center for disease control and prevention (2014). Ebola (Ebola Virus Disease) treatment. Retrieved from http://www. cdc. gov/vhf/ebola/treatment/index. html Center Watch News Online (2014). Medicago collaborates with U. S. Army Medical Research Institute of Infectious Diseases for Ebola vaccine. Retrieved from http://www. centerwatch. com/news-online/article/1698/medicago-collaborates-with-us-army-medical-research-institute-of-infectious-diseases-for-ebola-vaccine#sthash.
TQxPkVAj.dpbs Clinical Trials. gov (2014). Experimental Vaccine for Prevention of Ebola Virus Infection. Retrieved from https://clinicaltrials. gov/ct2/show/record/NCT00374309? term=ebola&rank=3 Creswell, J. W. (2008). Educational research: Planning, conducting, and evaluating quantitative and qualitative research (3rd). Upper Saddle River, NJ: Prentice Hall. 2008, p. 300. ISBN 0-13-613550-1 Shayne G. , C. (2009). _Clinical Trials Handbook. _ John Wiley & Sons. pp. 118. World Health Organization (2014). Ebola virus disease. Retrieved from http://www. who. int/en/.