What is a scientist's primary concern in a clinical trial?

The primary concern of the scientist in clinical trial is patient safety.

A clinical trial is one of the final stages of any research process according to the requirement. Studies are done to find if the approach of the research and treatment is effective.

Clinical test or trial on human beings is done only after the pre-clinical phase which involves laboratory studies on animals (in vitro) to check the safety and efficiency of the drug. Animals are quite different from humans so human clinical trials are required to be done.

The main aim of clinical trial involves three major things to be considered: if the drug is working, the efficiency of the drug as compared to the currently present drug and most importantly that the drug is safe for human use and the patient is safe after the administration of the drug into the body.