The drug discovery process begins with observing how a disease changes biological processes in the body. Researchers look into what might be causing the disease, typically with the goal of identifying proteins in the body that might be involved in the disease process. They then form a hypothesis that inhibiting or activating a specific protein might potentially help to treat the disease. Proteins are the most common drug targets because they play various critical roles in the body, but drug targets can also include DNA or ribonucleic acid (RNA). A good target is one whose activity can be both linked to the way the disease works and how it can be modified by a drug.

During this phase, collaboration is key. Our scientists are involved in projects and strategic alliances with universities, charitable research organisations and other pharmaceutical companies, all working together to understand the disease and its causes. 

We focus our efforts in core areas where we are best positioned to develop unique medicines for conditions; chronic inflammatory and autoimmune diseases, vaccines, oncology, pain, cardiovascular and metabolic diseases, and rare diseases.

Scientists begin searching for a molecule that will work on a specific disease target such as a gene or protein. Through ‘rational drug design’ scientists can create a molecule from scratch using cutting-edge chemistry and biotechnology. Alternatively, scientists can use ‘libraries’ of existing molecules, where thousands of potential candidates can be tested by automated systems.

Thousands of molecule combinations are screened in the hope of finding one or more promising candidates that show signs of potentially stopping or reversing a disease.

Medicines need to be tested to check they are safe, and are effective at treating or preventing the disease they were developed for, prior to applying for a licence to make them available to the public.

There are four stages of testing investigational medicines in human subjects:³

Phase 1 – A small number of healthy volunteers
Phase 2 – A larger group of people with the disease
Phase 3 – Typically several thousand patients
Phase 4 – Ongoing monitoring during the lifespan of the medicine

Trials are often run in partnership with universities, hospitals, general practitioners and the government.

Information about clinical trials that Pfizer conducts is publicly available on www.clinicaltrials.gov and www.clinicaltrialsregister.eu.