What Is a Clinical Study? Why Is It Important for Cancer Treatment and Patients?

A clinical study is research using human volunteers (participants) to increase medical knowledge. There are two main types: clinical trials (interventional studies) and observational studies.

In a trial, participants receive specific interventions according to a research plan or protocol. These may be medical products such as medicines or devices, procedures, or behavioral changes such as diet. Trials may compare a new approach with standard treatment, placebo without active ingredients or no intervention. Some compare existing treatments. With a new product or approach, whether it is more beneficial, harmful or different is generally unknown. Researchers measure outcomes to determine safety and efficacy.

Common patient outcomes in cancer treatment include:

Overall survival (overall survival): How long patients live after treatment

Progression-free survival (progression-free survival): Time after treatment during which tumors do not grow

Overall response rate (overall response rate): Percentage of patients whose tumors shrink with treatment

Drug development trials, generally ranging from I to III, are described as phase studies. These stages are defined by the United States Food and Drug Administration (FDA) .

In some countries, people ineligible for a trial may receive, through an Expanded Access Program outside the trial, experimental medicines or devices.

Observational Studies

Researchers assess health outcomes in participant groups according to a plan or protocol. Participants may receive interventions or procedures as routine care, but researchers do not assign specific interventions as in a trial. For example, a group of adults may be observed to learn how different lifestyles affect heart health.

Who Conducts Clinical Studies?

A principal investigator, usually a medical doctor, leads each study. Teams may include doctors, nurses, social workers and other health professionals.

Studies may be funded by national health authorities, pharmaceutical companies, academic medical centers, volunteer groups and other organizations. Doctors, other healthcare providers and individuals may also sponsor trials.

Where Are Clinical Studies Conducted?

Usually in universities and hospitals. Legal changes in our country this year also allow private hospitals to participate.

How Long Do Clinical Studies Last?

Duration varies according to what is investigated. Participants are told before enrollment how long it will last.

Why Are Clinical Studies Conducted?

Generally, studies contribute medical knowledge about treating, diagnosing and preventing conditions. Common reasons include:

• Evaluating one or more interventions (medicines, devices, surgery or radiation) to treat a disease, syndrome or condition
• Finding ways to prevent initial development or recurrence, potentially including medicines, vaccines and lifestyle changes
• Evaluating interventions intended to identify or diagnose a condition
• Examining methods to identify a condition or its risk factors
• Discovering and measuring ways to improve comfort and quality of life through supportive care in chronic disease

Why Are Clinical Studies Important for Cancer Treatment and Patients?

Cancer has over 100 types, is difficult to treat and, particularly at stage 4 (metastatic disease), currently offers a low chance of complete cure. New drugs and approaches are urgently needed. Half of worldwide clinical trials therefore concern cancer; currently, 57,722 cancer trials are underway.

Map showing cancer trial numbers worldwide as of 19 November 2016. Information comes from the https://ClinicalTrials.gov website, where all clinical trials must be registered.

Clinical Trials in Cancer:

• New treatments, especially medicines, can be developed only through trials.
• Trials determine whether treatments produce responses in patients.
• Different drug combinations are tested to identify the best treatment.
• Adverse effects are identified through trials, enabling effective management.
• Trial results are the most important step in advancing cancer research.

On this subject, in our next article we will discuss eligibility, frequently asked questions and the situation in our country.