What is a clinical trial?
Every trial follows a fixed plan, the study protocol. It sets out which question the trial is to answer, who can take part, which examinations take place and how the results are analysed.
There are different kinds of studies: a medicine trial (clinical trial of a medicinal product) examines a medicine. Other studies test medical devices or surgical procedures, or only observe how a condition develops.
In the European Union, no new medicine can be approved without clinical trials. Trials are therefore an important part of medical research – whether a new treatment is better than the current one is exactly what a trial is meant to find out.
Sources: [1] Regulation, [6] European Medicines Agency
How does taking part work?
It starts with information: you read what a study is about and, if you are interested, enquire without obligation. The study site gets in touch if taking part might be possible.
In the information discussion, a doctor from the study team explains the study. You also receive all information in writing and have time to think it over and to talk to your family or your GP.
After your written consent, screening examinations follow. They show whether you meet all requirements. Only then does the actual study period begin, with appointments according to plan. There is often a follow-up at the end.
- Information and enquiryYou read about a study and enquire without obligation.
- Information discussionThe study team explains the aim, procedure, risks and your rights.
- ConsentOnly after time to think do you give written consent – or not.
- ScreeningExaminations show whether you meet the requirements.
- Study periodAppointments according to plan, with medical care.
- CompletionFollow-up and, later, a summary of the results.
Sources: [1] Regulation
Phases I to IV
In phase I, a substance is used in a small number of people for the first time, often healthy volunteers. The focus is on safety and dose.
In phase II, people with the condition take part. The question is whether the medicine works and which dose is right. Phase III tests it in larger groups, often compared with standard treatment or a placebo. After that, approval can be applied for.
Phase IV starts after approval: how does the medicine perform in everyday use and over a longer time?
- Phase Ia few people, often healthy volunteerssafety, tolerability, dose
- Phase IIpeople with the condition, smaller groupseffect and the right dose
- Phase IIIlarge groups, often in several countriescomparison with standard care or placebo
- Phase IVafter approval, in everyday uselong-term safety and use
Sources: [6] European Medicines Agency, [4] ClinicalTrials.gov
Who can take part?
Every study looks for people who meet certain requirements, such as an age, a particular condition or a previous treatment (inclusion criteria). Other circumstances rule out taking part, such as certain other illnesses or a pregnancy (exclusion criteria).
Whether you can take part is always checked by the study site. Many enquiries do not match a study – that is normal and says nothing about you.
Some studies look for healthy volunteers, especially in phase I. Studies for people with a condition are separate: they are about treating that condition.
Sources: [4] ClinicalTrials.gov
Possible benefits and risks
Participants usually receive close medical care and access to a treatment that is being tested. A personal benefit cannot be promised, though.
Possible risks include known and unknown side effects as well as extra time for appointments and examinations. In many trials, chance decides which treatment someone receives (randomised). Sometimes neither you nor the study team know which group you are in (blinded). A placebo is a dummy medicine without an active substance; where an effective treatment exists, it is usually given in addition to standard treatment.
In the information discussion you will learn which risks are known for your study. Ask about anything that matters to you.
Sources: [1] Regulation, [5] World Medical Association: Declaration of Helsinki
Your safety and your rights
In the EU, a medicine trial may only start once the competent authority and an independent ethics committee have reviewed and approved it.
You have the right to an understandable explanation, to time to think and to ask questions. You give written consent and can withdraw it at any time – without any disadvantage to you.
Under EU law, compensation must be ensured for harm caused by taking part in a medicine trial. After the trial ends, a summary of the results in plain language is published in the EU register.
Sources: [1] Regulation, [5] World Medical Association: Declaration of Helsinki
Costs and effort
The study medicine and study-related examinations are usually paid for by the sponsor of the study. Some studies reimburse travel costs or pay compensation for your time and effort. Whether this is planned is shown on the study page or explained in the information discussion.
Under EU law, nobody may be pressured into taking part through money or other advantages. Plan time for appointments: how many there are and how long a study lasts varies a lot.
Sources: [1] Regulation
Where trials are registered
Medicine trials in the EU are listed in the Clinical Trials Information System (CTIS). In Germany there is also the German Clinical Trials Register (DRKS); internationally, ClinicalTrials.gov is widely used.
The registers show the official trial number, the sponsor and the countries involved. Feel free to ask the study site for a study’s register number.
Sources: [2] Clinical Trials Information System, [3] German Clinical Trials Register, [4] ClinicalTrials.gov
Frequently asked questions
All answers by topic. Choose a topic.
Understanding clinical trials
What is a clinical trial?
A clinical trial is a scientific study involving people. It tests, for example, whether a new medicine works, how well it is tolerated and whether it is better than the current treatment.
Every trial follows a detailed plan, the study protocol. It defines who can take part, which examinations take place and how the results are analysed. No new medicine can be approved in the European Union without clinical trials.
Source: Regulation (EU) No 536/2014, Article 2 (opens in a new tab)
What is a medicine trial?
A medicine trial – in legal terms a “clinical trial” – examines how a medicine works in people, how well it is tolerated and at which dose it should be used. It runs in phases and, in the EU, may only start once the competent authority and an ethics committee have approved it.
Other studies examine medical devices, for example, or only observe how a condition develops without prescribing a treatment.
Source: Regulation (EU) No 536/2014, Art. 2 (opens in a new tab)
Can a trial be an option if my treatment is not working well enough?
Yes, this is one of the most common reasons people look into clinical trials. Trials test new medicines and therapies before they are generally available. Many trials are aimed specifically at people whose current treatment does not work well enough or is not well tolerated.
Important: finding out whether the new treatment works better is what the trial is for. Depending on the trial, participants receive the new treatment, the current standard treatment or a placebo – usually in addition to standard treatment. Whether taking part is possible and makes sense for you is something to clarify with the study site. Ideally, talk to your own doctor as well.
Why are clinical trials important?
Almost every treatment we take for granted today was tested in clinical trials. Trials show whether a new therapy really helps and what risks it has – under controlled conditions and with medical care.
For participants, a trial can mean access to a new treatment before it is generally available. Whether the new treatment works better than the current one is exactly the open question the trial tries to answer, so a personal benefit cannot be promised.
What do phases I to IV mean?
Medicine trials run in successive phases:
- Phase I: A new medicine is given to a small number of people for the first time, often healthy volunteers. The focus is on safety and dosage.
- Phase II: People with the condition take part. The trial looks at whether the medicine works and which dose is suitable.
- Phase III: Larger groups, often at many study sites in several countries. The medicine is usually compared with the standard treatment or a placebo. The results are the basis for approval.
- Phase IV: After approval, researchers observe how the medicine performs in everyday use and over a longer period.
Each study page shows the phase under “At a glance” where it has been provided.
What types of studies are there?
There are two broad types:
- Interventional studies: Participants receive a specific treatment, such as a new medicine or a medical device. Medicine trials in phases I to IV belong to this group.
- Observational studies: No treatment is assigned. Doctors document how a condition or a usual treatment develops.
The study page says which type a study is.
What is a placebo – does that mean I get no treatment?
A placebo is a dummy medicine without an active ingredient that looks exactly like the medicine being tested. Comparing against a placebo shows reliably which effects really come from the medicine.
Importantly, where an effective treatment exists, it is usually not withheld. Often all participants receive the standard treatment, and the new medicine or the placebo is given in addition. Whether and how a study uses a placebo is stated on the study page and explained in detail in the information discussion.
What do “randomised” and “blinded” mean?
Randomised means that a random process decides which treatment you receive in the study. This keeps the groups comparable, so the result is not distorted by who gets which treatment.
Blinded means that you do not know which treatment you receive. In double-blind studies, the study doctors do not know either. In an emergency, the assignment can be revealed at any time.
Where can I check that a trial is officially registered?
Medicine trials in the European Union are published in the EU’s public register (euclinicaltrials.eu (opens in a new tab)). Many trials are also listed in the international register ClinicalTrials.gov (opens in a new tab), and trials in Germany often in the German Clinical Trials Register (DRKS) (opens in a new tab).
These registers contain the study description, the participating countries and, later, the results. PatientCapsule shows only some of the ongoing trials: those you can enquire about through this portal.
Taking part
Who can take part in a clinical trial?
Each trial defines who it is for. These inclusion and exclusion criteria cover, for example, the condition and its stage, age, previous treatments and other conditions. They protect your safety and make sure the results are meaningful.
Each study page lists the main requirements. Whether you can actually take part is checked by the study site in a medical consultation and with screening tests.
Can I take part in a study as a healthy person?
Yes, some studies look for healthy volunteers – especially in phase I, when a substance is used in people for the first time.
PatientCapsule mainly presents studies for people with a particular condition. Who can take part is shown on every study page under “Who can take part?”.
Source: ClinicalTrials.gov, glossary “Healthy volunteer” (opens in a new tab)
What can I do if no study is running for my condition right now?
PatientCapsule only shows selected studies. You can find more studies in public registers, such as the EU register CTIS (opens in a new tab), the German Clinical Trials Register (opens in a new tab) or ClinicalTrials.gov (opens in a new tab).
Talk to your own doctor as well: they know your medical history and often know which centres do research on your condition. New studies appear on PatientCapsule as soon as they are published.
How do I find studies near me?
Enter your postcode in the study search. Studies with the nearest study location are then shown first.
Please note: a study only takes place at selected study sites. Not every place has a site close by. Your enquiry goes to the nearest participating site; you will learn how far away it is in the first conversation at the latest.
How does an enquiry through PatientCapsule work?
- Choose a study and read what it is about and who can take part.
- Answer a short questionnaire about your condition on the study page and enter your contact details. It takes a few minutes.
- You receive a confirmation by email.
- Your enquiry goes to the nearest participating study site. If your answers fit the study, the site contacts you, answers your questions and arranges an appointment if appropriate.
Enquiring is free and without obligation.
Am I enrolled once I have completed the questionnaire?
No. Completing the questionnaire only sends an enquiry. It is neither an enrolment nor a medical decision.
The study site will work out with you whether the trial might be suitable. You can only take part after receiving detailed information, having the chance to ask questions and giving your written consent. Until then, you can say at any time that you do not want to take part.
How soon will the study site contact me?
It varies between study sites. You will first receive an email confirming your enquiry. We cannot guarantee when the study site will contact you. If you have questions about your enquiry, email us at trials@mediorahealth.com.
What happens if the study is not suitable for me?
You receive a message that your enquiry has been closed. Your personal details are deleted six months later; the email gives the exact date.
If you have joined our study pool and confirmed this by email, we let you know about other studies that might suit you. You can leave at any time.
What happens in the information discussion?
A study doctor explains the study to you: its aim, the procedures, possible benefits and risks, other treatment options and your rights. You receive written patient information and have enough time to think it over.
Ask anything that matters to you – you are welcome to bring someone you trust. Only when you agree do you sign the consent form.
Source: Regulation (EU) No 536/2014, Article 29 (opens in a new tab)
What is the screening phase?
After you consent, the study site checks with screening tests whether you meet all requirements – for example blood tests, imaging or a physical examination.
The study treatment only starts once all criteria are met. Sometimes it turns out only during screening that taking part is not possible.
Can I keep my own doctor?
Yes. Your GP and specialists remain available to you. With your consent, the study site coordinates with them, for example about your medicines and previous findings.
It is a good idea to tell your doctors if you are considering taking part. They know your medical history and can advise you.
How much time does a study take?
This varies a lot. Some studies have few appointments, others run for months or years with regular visits to the study site.
Each study page shows the duration and procedures under “At a glance” and “What to expect” where known. The information discussion tells you how many appointments there are and how long they take.
Can I enquire on behalf of a relative?
Yes, if the person concerned agrees. It is best to fill in the questionnaire together, because the questions are about their condition. Enter contact details at which the study site can reach you or the person concerned.
The information discussion and consent always involve the person who would take part in the study.
Safety and your rights
Who checks that a study is safe?
Before a medicine trial may start in the European Union, the competent medicines authority and an independent ethics committee must review and approve it. This is governed by the EU Clinical Trials Regulation (Regulation (EU) No 536/2014). In Germany the responsible authority is the Federal Institute for Drugs and Medical Devices (BfArM) or the Paul-Ehrlich-Institut, in Austria the Federal Office for Safety in Health Care (BASG).
During the trial, participants are monitored medically, and side effects are recorded and evaluated continuously. If unexpected risks arise, a trial can be changed or stopped.
Source: Regulation (EU) No 536/2014, Articles 4–8 (opens in a new tab)
What risks and side effects should I expect?
Any treatment can have side effects – including a new one. With a medicine still being tested, not all side effects are known yet. This is one reason why participants are monitored particularly closely.
The information discussion explains the known risks. During the study you have a named contact at the study site and usually receive contact details for emergencies. Always report any complaints straight away.
Am I insured during a study?
For medicine trials in the EU, it must be ensured that participants are compensated for damage caused by the trial (Article 76 of Regulation (EU) No 536/2014). In Germany this is usually done through participant insurance taken out by the sponsor.
You receive the insurance terms and what to do in case of damage with the study documents.
Source: Regulation (EU) No 536/2014, Article 76 (opens in a new tab)
Can I stop taking part at any time?
Yes. Taking part in a clinical trial is voluntary. You can stop at any time without giving a reason, with no disadvantage for your further medical care.
For your safety, it is sensible to inform the study site and attend a final check-up, but you are not obliged to do so.
Source: Regulation (EU) No 536/2014, Article 28(3) (opens in a new tab)
What are my rights as a participant?
- You are informed clearly before taking part and can ask any question.
- You decide freely and have time to think.
- You can withdraw your consent at any time.
- You are told about new findings that matter for your decision.
- You have the rights of the General Data Protection Regulation, such as access to your data.
- You have a named contact at the study site throughout the study.
Will I learn the results of the study?
For medicine trials in the EU, the sponsor generally has to publish a summary of the results within one year of the end of the trial – including a summary in plain language. It appears in the EU’s public register (euclinicaltrials.eu (opens in a new tab)).
Ask the study site whether and how you will be informed about the results.
Source: Regulation (EU) No 536/2014, Article 37 (opens in a new tab)
Costs and effort
What does it cost to take part in a clinical trial?
Enquiring through PatientCapsule is free. The study medicine and the examinations required for the study are usually paid for by the study sponsor, so you normally have no costs for them.
Your usual treatment continues to be covered by your health insurance as before. The study site explains the details before you take part.
Is there compensation or reimbursement of travel costs?
That depends on the study. Many studies reimburse travel costs to study appointments, some pay compensation for your time. In patient studies, compensation is not the main point – it is meant to offset your effort.
What applies to a study is shown on its page under “Compensation” where provided.
Are study participants paid?
Patients are usually not paid. Some studies reimburse travel costs or pay compensation for time and travel. Whether this is planned is shown on the study page or explained in the information discussion.
Under EU law, nobody may be pressured into taking part through money or other advantages.
Source: Regulation (EU) No 536/2014, Art. 28 (opens in a new tab)
Privacy
Who sees my answers from the questionnaire?
Only these see your contact details and answers:
- the study site your enquiry goes to, and
- the MediOra Health team that handles enquiries.
Companies that fund or conduct the study (sponsors) only receive aggregated figures – no names, no contact details and no answers.
Before you send the questionnaire, it shows you what information is requested and what you consent to. Details are in the privacy policy.
How is my data protected?
Your answers are sent encrypted and stored encrypted. Only the study site handling your enquiry and authorised MediOra Health staff can access them. We do not sell data, and your answers are never used for advertising or analytics.
You can find the details in our privacy policy.
How can I withdraw my consent and have my data deleted?
You can withdraw your consent at any time – with the link in the confirmation email or by writing to trials@mediorahealth.com.
We then no longer contact you, and the study site can no longer see your enquiry. Your details are deleted 14 days later; until then you can undo the withdrawal. On request, we delete them immediately. Without a withdrawal, your details are deleted six months after your enquiry is closed.
If you have already taken part in a study, the legal rules for clinical trials also apply to the data collected in the study. The study site explains what happens to your data in that case. More in the privacy policy.
About PatientCapsule
What is PatientCapsule?
PatientCapsule is the patient portal of MediOra Health. We explain how clinical trials work and present selected studies. A short questionnaire helps you check whether a study might suit you, and we pass your enquiry on to the nearest participating study site.
MediOra Health helps study sites and sponsors find people for whom a study may be suitable. Read more about us and how our content is created under Who is behind PatientCapsule?.
Is PatientCapsule a clinic, or can I get medical advice here?
No. PatientCapsule is not a clinic or a doctor’s practice. We do not give medical advice and do not run studies ourselves. Each study is run by the participating study sites.
For questions about your condition or treatment, please talk to your doctor.
Which studies can I find on PatientCapsule?
PatientCapsule presents selected clinical trials. For each study you can see whether it is recruiting, opening soon or not recruiting at the moment. The questionnaire for your enquiry is available for every study marked “Recruiting”.
In the studies overview you can also search by postcode: studies with the nearest participating sites in your country are then shown first.
PatientCapsule is not a complete directory of all studies. Public registries such as euclinicaltrials.eu (opens in a new tab) and ClinicalTrials.gov (opens in a new tab) give a comprehensive overview.
How can I contact the PatientCapsule team?
Write to us at trials@mediorahealth.com. After your enquiry, questions about a specific study are answered by the responsible study site.
Sources
The general statements on this page are based on these publicly available sources.
- Regulation (EU) No 536/2014 on clinical trials on medicinal products for human use (opens in a new tab)
- Clinical Trials Information System (CTIS) of the EU – public register (opens in a new tab)
- German Clinical Trials Register (DRKS) (opens in a new tab)
- ClinicalTrials.gov – register and glossary of the U.S. National Library of Medicine (opens in a new tab)
- World Medical Association: Declaration of Helsinki – ethical principles for medical research involving human participants (opens in a new tab)
- European Medicines Agency (EMA): Clinical trials in human medicines (opens in a new tab)
Editorial responsibility
This page is the editorial responsibility of MediOra Health. It contains general information and does not replace medical advice. It does not describe any particular condition or study; information about a study is on its own study page.
Last reviewed: · Next review by: 28 October 2027