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Research in clinical practice

Research in clinical practice

Before a new drug becomes available, an extensive Research & Development process is carried out. An important part of this is human research, in which it is determined that the drug is effective and has an acceptable safety profile. At Janssen, we believe that transparency advances science and medicine. That is why we provide openness about the results of clinical research.

Four clinical research phases

Drug research begins with identifying a molecule with a therapeutic effect, the drug candidate. When a drug candidate has been shown to be sufficiently safe to investigate efficacy in humans, the clinical investigation phase begins. In the clinic, a drug is generally first tested in generally healthy people (phase 1). In phase 2-4, a drug is then tested in people who are ill. This of course takes place under strict conditions; drug testing must meet the guidelines for Good Clinical Practice (GCP). This international standard guarantees the rights, safety and well-being of the participants in the study.

Clinical research into the safety and effectiveness of a potential drug thus takes place in four phases:

  • In phase 1, the drug is administered to people for the first time. In small groups (20-80 persons) of (usually healthy) volunteers, research is done into safe dosage and possible side effects.
  • In phase 2, the efficacy of the drug is tested on patients who have the disease in question. This research phase usually lasts two years and concerns about 100 to 500 patients.
  • Phase 3 is the most extensive clinical research phase. These studies can last more than four years. Several hundred to thousands of patients participate. Data on safety, efficacy and overall benefit-risk ratio of a potential drug are recorded in a comprehensive file. The drug is compared with a placebo (non-active substance) and/or with the current standard treatment. We do this to be able to answer the question whether the new drug is better and/or safer than the treatment that is already available.
  • Phase 4 takes place after the drug is available to be prescribed. This phase is meant to carefully monitor the safety and effectiveness, now that the drug is used in daily practice by an extensive group of patients for a longer period of time.

Clinical research as an important part of R&D activities

Clinical research is an important part of Janssen’s R&D activities. In 2019, for example, Janssen Belgium, in collaboration with various research centers, carried out 179 active studies involving more that 1500 patients and healthy volunteers.

Drug research does not always lead to the innovations we hope for. Sometimes a drug turns out not to be suitable for human use or does not bring significant improvement for the patient. Then we end the research program. This happens more often than many people think: of all the potential drugs in the first phase of clinical research, only 9.6% eventually become available to patients.1

Openness about clinical research

That a drug candidate does not reach the patient does not mean that the activities were wasted effort: the knowledge gained always feeds the next steps in development programs.

For this reason, we believe it is important to share the results of clinical research, including those from early termination clinical research programs. Janssen makes information about all its clinical trials with patients public through publicly accessible registers such as the EU Clinical Trials Register. This only concerns information that cannot be traced back to individuals. Study results are shared with the worldwide participants via the relevant research physicians. Since 2014, physicians and researcher scan also contact the Yale Open Data Access (YODA) project for information about Janssen clinical trials.

1Thomas, David W. et al (2016). Clinical Development Success Rates 2006-2015. BIO/BioMedTracker/Amplion

EM-47356 - 16-nov-2020