Question 1

What is a clinical trial?

Accepted Answer

A clinical trial is a research study that tests a new medical treatment, drug, device, or therapeutic approach in human volunteers. Trials are how researchers determine whether new treatments are safe, effective, and better than current standard-of-care options. Every FDA-approved drug and many medical devices went through clinical trials before becoming available to the public. Participation is always voluntary, and participants can withdraw at any time. Clinical trials are essential for advancing medicine, and without volunteers, new treatments cannot reach patients who need them.

Question 2

What do the phases mean?

Accepted Answer

Clinical trials progress through four phases, each with a different purpose and scale. Phase 1 trials test safety and dosage in a small group (20-100 people), often healthy volunteers. Phase 2 trials test effectiveness and side effects in a larger group (100-300 people) with the target condition. Phase 3 trials are large-scale studies (1,000-3,000+ people) that compare the new treatment to the current standard of care. These are the trials closest to potential FDA approval. Phase 4 trials monitor drugs already on the market for long-term effects and rare side effects. Most recruiting trials on our site are Phase 2 or Phase 3.

Question 3

Is it safe to join a clinical trial?

Accepted Answer

All clinical trials in the United States must follow strict safety protocols overseen by institutional review boards (IRBs) and data safety monitoring boards (DSMBs). The IRB reviews the study design before it begins to ensure risks are minimized and justified by potential benefits. The DSMB monitors ongoing results and can halt a trial early if safety concerns emerge. However, all medical interventions carry some risk, and experimental treatments may have unknown side effects. Participants receive detailed informed consent documents explaining all known risks. Talk to your doctor about whether a specific trial is appropriate for your situation.

Question 4

Where does this data come from?

Accepted Answer

All trial data comes from ClinicalTrials.gov, the world's largest database of clinical studies, maintained by the U.S. National Library of Medicine (NLM). Federal law requires most clinical trials conducted in the United States to be registered on ClinicalTrials.gov, and many international trials are registered voluntarily. The database contains over 450,000 studies from 220+ countries. We pull recruiting trials, translate the eligibility criteria from medical jargon into plain English, and organize them by condition so patients and caregivers can find relevant trials without a medical degree.

Question 5

How do I know if I qualify for a trial?

Accepted Answer

Each clinical trial has specific eligibility criteria that determine who can participate. Common criteria include age range, diagnosis, stage of disease, prior treatments, and overall health status. Some trials are very specific (e.g., adults aged 18-65 with untreated Stage III non-small cell lung cancer), while others are broader. We translate these criteria from clinical language into plain English on each trial page. To confirm eligibility, contact the trial site directly using the contact information provided, or ask your doctor to review the study and refer you if appropriate. Many trials also have a prescreening phone call to assess eligibility before any in-person visits.

Question 6

Will I have to pay to participate in a trial?

Accepted Answer

In most clinical trials, the study sponsor (pharmaceutical company, research institution, or government agency) covers the cost of the experimental treatment, study-related tests, and procedures. Participants typically are not charged for the investigational drug or device. However, some trials may not cover routine care costs like doctor visits or tests you would have received outside the trial. Many trials also provide compensation for time and travel, ranging from modest stipends to significant payments depending on the study requirements. Each trial's financial details are outlined in the informed consent document, so review it carefully and ask questions before enrolling.

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