Clinical Trials

What Are Clinical Trials?

Clinical trials are research studies performed in people that are aimed at evaluating a medical, surgical, or behavioural intervention. It’s the primary way for researchers to find out if a new treatment, like a new drug or a medical device, is safe and effective in people.

How do clinical trials work?

Therapeutical studies during which new treatment methods are tested are so called interventional studies. Participants are assigned to groups that receive one or more intervention/treatment so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes. Non-interventional studies, on the other hand, are observational studies without any interventions at all.

Clinical trials involve several phases. The efficacy of new treatments will be tested on patients only if the tolerability and effects of these treatments have been investigated in healthy volunteers.

• Phase I trials are small trials during which a new treatment is used in healthy human volunteers. During this stage, fundamental characteristics such as tolerability and safety of a new type of medication are tested in order to find out whether it is suitable for use in humans.
• Phase II trials are somewhat larger than Phase I trials as they usually involve 100 to 300 participants. In Phase II, medication is given for the first time to patients who actually suffer from the disease which the medication has been developed to treat. The aim of this phase is to find the right dosage. In addition, initial data about efficacy is gathered.
• Phase III trials are large-scale studies. They provide relatively precise information about efficacy and tolerability. In most cases, these involve comparative studies where patients receiving the treatment being investigated are compared with another control group that receives another treatment.
• Phase IV trials take place when a drug is already on the market. There are various reasons for Phase IV trials. It can be advisable, for example, to test an already approved medication in patients with a certain condition. Phase IV trials also provide valuable information on any rare side-effects of a drug as more patients are receiving treatment with it.

Clinical trials at DZI – Clinical Trial Register

The Central Study Registry of Universitätsklinikum Erlangen provides an overview of ongoing oncological and non-oncological trials (in German).

To search for a trial, enter your search term directly in the search field. You can limit the search results by using the filter function in the column on the left-hand side. 

For a better understanding, we recommend this short animated film that explains terms such as ‘randomisation’, ‘control group’, ‘placebo’ and others in various languages.