Pfizer
Pfizer is one of the largest biopharmaceutical companies in the world by research expenditure, with a clinical trial portfolio spanning oncology, rare diseases, vaccines, immunology, internal medicine, and neurology. Founded in 1849, Pfizer has brought more than 350 medicines and vaccines to patients globally, and today maintains one of the broadest Phase 2 and Phase 3 pipelines in the industry. Their clinical research operations span over 150 countries, making Pfizer trials accessible to a wide and diverse patient population.
Pfizer's oncology program — operating largely through its Pfizer Oncology unit — focuses on precision treatments including CDK4/6 inhibitors (palbociclib), EGFR-targeted therapies, antibody-drug conjugates, and immuno-oncology agents. Outside of cancer, Pfizer conducts extensive trials in cardiovascular and metabolic disease (including its ATTR cardiomyopathy drug tafamidis), rare pediatric conditions, and infectious disease. The COVID-19 mRNA vaccine program, conducted in partnership with BioNTech, included one of the largest Phase 3 vaccine trials in history with over 40,000 participants across six countries.
Participants in Pfizer-sponsored trials receive investigational treatments at no cost and are monitored by independent Data Safety Monitoring Boards. Pfizer trial sites are typically major academic medical centers, teaching hospitals, and specialist clinical research organizations. Eligibility criteria vary by study; most trials are listed on ClinicalTrials.gov with a direct contact link to the enrolling site.