Ethics in Clinical Trials

Patient Recruitment

A doctor is talking to a group of people.

Bayer follows the strictest scientific and ethical principles, always in accordance with applicable law, when carrying out research on humans – especially when it comes to patient recruitment.

Awareness of benefits and potential risks

Each patient needs to be aware of the possible benefits and risks involved in taking part in a clinical trial.


In addition to making a personal contribution to medical progress, one of the central motivating factors for participating in a clinical study is at the same time its most valuable potential benefit: patients have access to a medication that is not yet available on the market, a medication which may be able to shorten the course of their disease, prolong their lives or improve their quality of life.




A possible risk in taking part in a clinical trial is that the drugs being tested may be less effective or of lower tolerability than the currently used standard therapy. Furthermore, new forms of treatment may be accompanied by unforeseeable undesired effects.


Patients are informed that Phase III trials compare a new drug candidate with the current standard therapy or a pharmacologically inactive placebo if no standard therapy exists. Participants are randomly assigned to the standard therapy group or the treatment group under investigation, usually by computer. This method, called randomization, helps to avoid bias and ensures that human choices or other factors do not affect the study's results.


However, medical progress and innovation would not be possible without these patients – by participating, they play a crucial role in ensuring that a medicinal product, proven to be safe and effective, can be submitted for regulatory approval and made available to other patients.


Rights and responsibilities of trial participants

The decision to enroll in a clinical trial provides the patients with extensive rights. Before any clinical trial begins, the attending physician is required to inform patients of all important facts and details of the study in both written and oral form. The patients are asked to confirm their willingness to participate in the trial by signing a written Informed Consent form, a copy of which is provided to the patient for future reference. Informed Consent Forms must be approved by the respective institutional review board, also known as independent ethics committees or ethical review boards, before they can be provided to the patient.




Since participation in a clinical trial is entirely voluntary, the patient is free to decide whether she/he should participate in the clinical study and has the right to withdraw from the study at any time without having to provide any reasons and without affecting the standard medical care. Patients must immediately be informed by the investigating physicians in case any new findings concerning the benefits, risks or undesirable effects of the study medication become available during the trial. Pharmaceutical law furthermore stipulates that the sponsor of a clinical study has to obtain insurance coverage for all participating patients.


This ensures that compensation is available should a patient suffer study-related adverse health effects either during the study or during the post-trial observation period despite all precautionary measures having been taken.


To protect the collected personal and study data of the participants, all data are encoded during and after the study; in this way, the identity of the patients is kept confidential.


By deciding to enroll in a clinical study, patients however also accept certain responsibilities, such as informing their attending general practitioner or medical specialist of their participation as well as strictly adhering to study required procedures such as dosing times, attendance to check-up visits and keeping investigating physicians promptly apprised of any undesirable effects.


The “right” patient for clinical trials

An important objective in choosing patients is to make sure that the study represents the clinical reality of the actual population. For this reason, before the trial even begins, the subjects that may take part in the study are precisely defined based on specific inclusion and exclusion criteria. These criteria include, e.g., age and sex, diagnostic information, medical history and current state of health. In order to definitely attribute the results obtained to the study medication and not to other influences, only subjects with the predefined criteria are included in a study.


The use of clearly defined inclusion/exclusion enrollment criteria ensures that human subjects who could potentially be negatively impacted by participating in the clinical study are not exposed to this risk in the first place. Though important for all patients, this could be particularly significant for pregnant women, their fetuses and their future children; pregnant or nursing women are therefore sometimes excluded from clinical trials to prevent avoidable harm that could potentially be caused by experimental drugs.


The development of medicinal products for pediatric use is a special field of clinical research.