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CLINICAL TRIALS. DEFINITION. It is a systematic study of a new drug in human subjects to generate data for discovering or verifying the clinical claims or pharmacological and adverse effects with an aim to determine the safety and efficacy of the drug in question.
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DEFINITION It is a systematic study of a new drug in human subjects to generate data for discovering or verifying the clinical claims or pharmacological and adverse effects with an aim to determine the safety and efficacy of the drug in question.
controlled experiment having a clinical event as an outcome measure, done in a clinic or clinical setting and involving person having a specific disease or health condition • Systematic and prospective study • Compares the effect and values of interventions against a control group in human subjects • Very powerful experimental technique for assessing the effectiveness of intervention
OBSERVATIONAL STUDIES: Groups are studied & contrasts made between groups The observed data collected are analyzed ANALYTIC STUDIES: Also called Experimental Study the impact of a certain therapy Ultimately the investigator controls factor being studied CLINICAL TRIAL: Considered the “true” experimental study “Gold Standard” of clinical research Often a prospective study that compares the effect and value of an intervention against a control in human subjects Classifications of Research Studies: Three Main Types
Historical MinuteFirst “Clinical Trials” • Clinical Trials have a long history – even if not acknowledged as Clinical trials • Formal record of clinical trials dates back to the time of the “Trialists”: • Dr. Van Helmont’s proposal for a therapeutic trial of bloodletting for fevers [1628] • Dr. Lind’s, a ship surgeon, trial of oranges & limes for scurvy [1747]
Historical MinuteFirst “Clinical Trials” Historical Highlights of Drug Trials • 1909: Paul Ehrlich - Arsphenamine • 1929: Alexander Fleming - Penicillin • 1935: Gerhard Domagk - Sulfonamide • 1944: Schatz/Bugie/Waksman – Streptomycin • By 1950, the British Medical Res. Council developed a systematic methodology for studying & evaluating therapeutic interventions
Core Components of Clinical Trials • Involve human subjects • Move forward in time • Most have a comparison CONTROL group • Must have method to measure intervention • Focus on unknowns: effect of medication • Must be done before medication is part of standard of care • Conducted early in the development of therapies
Core Components of Clinical Trials • Must review existing scientific data & build on that knowledge • Test a certain hypothesis • Study protocol must be built on sound & ethical science • Control for any potential biases • Most study- medications, procedures, and/or other interventions
TRIAL OBJECTIVES • The superiority of IND • Non inferiority of IND • The equivalence of the two NY/VI AETC
Components of Clinical Trial Protocols • Investigating two or more conditions so have two(+) groups • Ex: drug vs. placebo; medicine vs. surgery; low dose vs. high dose • Specific inclusion/exclusion criteria • Sample size & power calculations • Plan for: potential biases • Plan for: handling of attrition/loss to follow up
Identify eligible participants Explain study Provide informed consent Reassess eligibility Assign to one group Participants should be told: May have side effects (adverse effects) Time commitment Benefits & risks May withdraw at any time Enrollment 100% voluntary Study Participant Recruitment
PHASES OF CLINICAL TRIALS NY/VI AETC
Phase o: Microdosing study • New stratergy • Undertaken before phase 1 to decrease rate of rejection in further phases • Very low dose- 1/100th of estimated human dose or max. of 100 microgram • Healthy human volunteers • PK data- AMS, LC-MS • Reduce cost and time of drug development • Drawback- • Subpharmacological dose • Not expected to produce toxic or therapeutic effects NY/VI AETC
Phase I:(human pharmacology and safety) • Necessary / Cautious phase • Small group (25-40) • Healthy volunteers / patients • Non blind/ open label • Objectives – safety & tolerability pharmacokinetic differences in humans & animals safety clinical dosage range in humans pharmacodynamics of the drug in humans detect any predictable toxicity
Phase II:(therapeutic exploration and dose ranging) • Patients with the particular disease • 100-400 patients • Blinded or open label • Objective – therapeutic efficacy dose range tolerability & safety as extension of phase I
Phase III (therapeutic confirmation/comparison): • Patients • Large group (500-3000) • Objective – value of drug relation to the existing therapy safety & tolerability possible drug interactions additional pharmacokinetic property • New drug Application (NDA) is formulated
Phase IV(post-marketing surveillance/studies): • Post marketing • Patients normally treated forming the larger group • Data through treating physicians • Special group (pregnant females, children, elderly) are also included • Modified dosage forms, additional routes of administration
Objectives – efficacy, acceptability & adverse effects uncommon/ idiosyncratic reactions unsuspected drug interactions pattern of drug utilisation & additional indications
Phase V /Effectiveness Research • The therapeutic effect is realized in day-to-day clinical practice • Field research or community-based research • Test generalization of the intervention to a larger sample and under typical and somewhat variable clinical contexts.
To compare effects found in later efficacy studies • Determine benefits from the treatment • Cost-benefit ratio of the intervention can be addressed
ETHICS OF CLINICAL TRIALS Protection of Participants 4 ethical principles guide clinical research: • RESPECT FOR PERSONS(AUTONOMY): freedom, dignity and confidentiality of the subject Treatment of person as autonomous • BENEFICENCE:motive to do good to the subject or society at large • JUSTICE:Treatment of all fairly & all equally share benefits & risks • NON-MALEFICENCE: not to do harm or put the participants at undue risk
Ethical Norms of Clinical Trials Sound study designs take into account: • Randomization or sharing of risks • Proper use of placebo • monitor safety of treatment • Competent investigators • Informed consent • Equitable selection of participants • Compensation for study related injuries
Why Some Participate: Give back to society Exhausted all other txs Health care services Payment & incentives Support Why Some Do Not? Mistrust of studies Do not want to be “guinea pig” Do not meet criteria Cannot give up time for study visits Barriers: lang., distance Participation in Clinical Trials NY/VI AETC
What is study about? What are the goals? Study sponsor? Participant input into protocols? Inclusion criteria? Benefits & risks Is there an incentive? How protected from harm? What is required: no. of study visit & what occurs? What happens after study is over? How results will be disseminated? Taking Part in Research Studies:Questions to Ask
Conclusions & Take Home Message • Research is soft science • Clinical trials often yield important results that affect health and well being • Clinical trials are susceptible to human error either on part of investigator or patient • Must follow guidelines & protocol • Must ensure well-being of participant