T2 Definitions & Questions

Phase II

Clinical studies that gather preliminary data on effectiveness in people with a particular disease or condition while further evaluating safety.

Phase II Clinical Trial

A generally short clinical trial involving fewer than 300 subjects that supports proof of concept, demonstrates evidence of efficacy, identifies dose regimens, defines the target population, and evaluates short-term safety.

Clinical Trial Protocol

The planned design, methods, statistics, objectives, patient population, recruitment strategy, trial design, study duration, methodology, outcomes, and informed consent process for a clinical trial.

Primary Objective

Evaluation of the efficacy of a therapeutic approach versus placebo or standard of care and estimation of the frequency and types of adverse events.

Secondary Objective

Evaluation of additional parameters associated with efficacy, such as quality of life, increased lifespan, decreased fracture frequency, and relationships between adverse effects and surrogate markers.

Target Population

The specific patient population with a particular disease or condition for which a therapy is being clinically evaluated.

Inclusion Criteria

Characteristics required for entry into a clinical study, based on factors such as diagnosis, that identify patients most likely to benefit and increase the probability of detecting treatment efficacy.

Exclusion Criteria

Characteristics that disqualify someone from participating because they may not benefit, may be harmed, or may introduce variables that mask therapeutic efficacy or confound interpretation.

Informed Consent

Voluntary agreement to participate in research.

Information Disclosure

Providing essential information that enables an individual to make an informed decision about participating in research.

Voluntarism

A voluntary decision to participate in a trial made freely and independently without coercion.

Decision-Making

The participant's ability to understand the nature and consequences of their health decision.

Parallel Trial Design

A clinical trial design in which separate groups receive different treatments, such as drug A versus drug B, drug versus placebo, or different doses of the same drug.

Factorial Trial Design

A clinical trial design in which groups of participants receive different combinations of interventions.

Cross-over Trial Design

A design in which each participant is randomized to a sequence of treatments that are administered during different treatment periods, allowing each participant to receive each treatment.

Non-inferiority Trial

A trial designed to compare a novel treatment with an established active treatment to demonstrate that the new treatment is not clinically worse for a specified endpoint, potentially while offering better safety or pharmacokinetics.

Regulatory Oversight

Oversight of clinical trials involving the Investigational New Drug application, Institutional Review Board, and New Drug Application.

New Drug Application (NDA)

An application providing the FDA with enough information to determine whether a drug is safe and effective, whether its labeling is appropriate, and whether its manufacturing methods adequately preserve its identity, strength, quality, and purity.

What are the five phases of clinical trials?

Phase 0, Phase I, Phase II, Phase III, and Phase IV.

What is the main purpose of Phase II trials?

To support proof of concept, show evidence of efficacy that supports future trials, identify dose regimens, define the target population, and evaluate short-term safety.

How many subjects are typically enrolled in a Phase II trial?

Fewer than 300 subjects.

Why is Phase II information important for Phase III?

Evidence of efficacy from Phase II helps determine the sample size needed for Phase III trials.

What type of endpoints are typically used in Phase II trials?

Surrogate endpoints rather than clinical endpoints.

What information should be included in a clinical trial protocol?

The target population, inclusion/exclusion criteria, recruitment strategy, single- or multicenter design, trial design, anticipated study length, methodology for evaluating effectiveness, clinical or surrogate outcomes, and informed consent process.

What should justify a clinical trial?

Its scientific background and rationale relative to other treatments for the disease, condition, or syndrome.

What are examples of primary efficacy objectives?

Evaluating pain relief, cancer remission, or increased bone mineral density compared with placebo or standard of care.

What are examples of secondary objectives?

Quality of life, increased lifespan, decreased frequency of bone fractures, and correlation of adverse effects with surrogate markers

What should be considered when evaluating clinical trial objectives?

Whether the objectives can be achieved with the available resources and within the proposed timeframe and whether they can be evaluated scientifically and quantitatively.

Why is patient selection important in clinical trials?

It provides an accurate and reliable clinical evaluation of a therapy in the target patient population.

What are the two steps involved in selecting patients?

Define the target population and establish criteria for selecting patients from that population.

Why can a heterogeneous target population be problematic?

Variation in characteristics and disease severity can decrease the accuracy, reliability, and generalizability of study findings.

How can bias and variability be reduced in a clinical trial?

By selecting a relatively homogeneous target population using defined criteria.

What factors can be used to establish eligibility criteria?

Age, gender, type and stage of disease or condition, previous treatment history, and other medical conditions.

Why are inclusion criteria used?

To identify patients who are most likely to benefit from the therapy and increase the probability of detecting treatment efficacy.

Why are exclusion criteria used?

To exclude patients who may not benefit or could be harmed and to eliminate variables that could mask efficacy or confound interpretation.

What is an example of an exclusion criterion based on safety?

A patient with a history of hypersensitivity to a structurally related drug would be excluded from a trial.

Why would a patient with underlying liver disease be excluded from a trial involving a hepatotoxic drug?

Because the underlying liver disease could increase the patient's risk of harm.

What does informed consent require?

Information disclosure, voluntarism, and decision-making capacity.

What information must participants receive before deciding whether to participate?

What will be done to them, how the research protocol works, what risks or discomforts they may experience, and that participation is voluntary.

Is an informed consent document a contract?

No. Participants may withdraw from a study at any time, even before the study is complete.

How does randomization help in a parallel trial?

It helps ensure accurate results and reduces the risk of bias.

What happens in a two-by-two factorial trial?

Participants are divided into four groups receiving drug A + drug B, drug A + placebo, placebo + drug B, or placebo + placebo.

What assumption is made in a factorial trial?

That there is no interaction between the different interventions.

What is an advantage of a cross-over trial?

Fewer participants are required because each participant serves as their own control.

What are other advantages of a cross-over trial?

Variables are balanced because each participant receives each treatment, and recruitment may be enhanced because participants know they will receive active treatment at some point.

What is a carry-over effect?

When the effects of one treatment persist and influence the response to a subsequent treatment in a cross-over trial.

How can a carry-over effect be minimized?

By allowing a washout period between sequential treatments.

What are disadvantages of cross-over trials?

Increased participant dropout, longer study duration, potential exposure of all patients to treatment toxicity, and inability to assess long-term efficacy or safety.

What is the goal of a non-inferiority trial?

To demonstrate that a novel treatment is not clinically worse than an established active treatment for a specified endpoint

What is generally assumed about the comparator treatment in a non-inferiority trial?

That it has already been established to have a significant clinical effect against placebo.

When can human drug studies begin?

After an IND has been reviewed by the FDA and a local IRB.

What does an IRB oversee in a clinical trial?

The clinical trial protocol, eligible participants, testing and procedure schedules, medications and dosages, study length, objectives, and other details, while ensuring informed consent and appropriate protection from harm.

What are the three major regulatory components associated with clinical trials?

Investigational New Drug application, Institutional Review Board, and New Drug Application.

What three key decisions does the FDA make using an NDA?

Whether the drug is safe and effective and its benefits outweigh risks, whether the proposed labeling is appropriate, and whether manufacturing methods adequately maintain the drug's identity, strength, quality, and purity.