Process of Medicines Discovery and Development

The steps involved in developing a new medicine are described below.

The concept of efficacy and safety of a medicine refers to the ability of a treatment to work while causing no unnecessary harm.

• This means that the benefit of taking a medicine, despite potential side effects, is higher than the risk of leaving the condition untreated.
• To phrase it differently a medicine is beneficial when it produces the desired effect (efficacy) with a suitably low chance of side effects (safety).

This is also known as the ‘benefit-risk relationship’ (or benefit-risk ratio, it was previously known as the risk-benefit ratio/relationship).

After a medicine becomes available to patients, the efficacy and safety still need to be monitored. This is called ‘pharmacovigilance’. This is typically co-ordinated by the pharmacovigilance department of the pharmaceutical company along with the Regulatory Authorities, healthcare professionals and patients. The World Health Organisation (WHO) defines pharmacovigilance as ‘[…] the science and activities relating to the detection, assessment, understanding and prevention of adverse effects or any other drug-related problem’ [1].

The concept of pharmacovigilance was introduced in the late 1960's, after the thalidomide disaster. Close to 10.000 babies were born with problems or ‘deformities’ caused by thalidomide taken by their mothers during pregnancy. At that time, thalidomide was sold mainly as a sedative, but it was also used for the treatment of morning sickness in pregnant women. It had never been tested for this indication (condition) since at that time (1957) no clinical trials in humans were required.

Based on this disaster, the concept of pharmacovigilance was put into action.

Today, before a medicine is made available to patients, it has typically been tested (depending on the disease) on a population of at least 5.000 persons. This corresponds to about 0.00007% of the world’s population [2]. The testing period for the medicine is based on a limited time period. This is why the long-term efficacy and safety of the medicine must be monitored and continuously evaluated while on the market, or, in other words, under ‘real-life’ conditions. If a patient gets any side effects, it is recommended that they talk to a doctor, pharmacist or nurse. This includes any possible side effects listed or not listed in the package leaflet. In many EU member states, side effects can be reported directly via the national reporting system available on the websites of the national competent authority (NCA). By reporting side effects more information will become available on the safety of a medicine.

1. The importance of pharmacovigilance. Safety monitoring of medicinal products by World Health Organization, 2002. http://apps.who.int/medicinedocs/pdf/s4893e/s4893e.pdf?ua=1
2. Pharmacovigilance: ensuring the safe use of medicines by World Health Organization, 2004 http://apps.who.int/medicinedocs/en/d/Js6164e/