Dr. Leonard S. Schleifer, M.D., Ph.D., is an American physician, the self-made billionaire Founder, Chairman, and CEO of Regeneron Pharmaceuticals (NASDAQ: REGN), a global leader in biotechnology and drug discovery. Born in New York City, in 1952, his career is rooted in medicine and neurology.

Schleifer holds an M.D. and a Ph.D. in Neurobiology from the University of Virginia. His career began as a neurologist, recognizing the immense, untapped potential of applying fundamental biology and genetics to the intractable problem of drug development. His philosophy centers on innovation, scientific integrity, and long-term commitment to R&D (shielding the company from short-term pressures).

• Regeneron Pharmaceuticals (Founder, Chairman & CEO): The core publicly traded asset, a global leader in biotechnology and drug discovery (developing Eylea, Dupixent, and REGEN-COV).
• Scientific Focus: His success is built on applying genetics and fundamental biology to drug development (in partnership with George Yancopoulos).
• Drug Apex: The company has developed ten FDA-approved or -authorized treatments (e.g., for blindness, eczema, and cancer).
• Academic Background: He holds an M.D. and Ph.D. in Neurobiology from the University of Virginia.

Dr. Leonard Schleifer founded Regeneron Pharmaceuticals in 1988, recognizing that the industry suffered from a lack of rigorous scientific method. His strategic genius was recruiting Dr. George Yancopoulos (a Ph.D. in Neurobiology and Molecular Biophysics) as the Chief Scientific Officer (CSO) and committing to vertical integration of research and clinical development. Their commitment to long-term scientific investment led to the development of Eylea (for blindness) and Dupixent (for eczema), which became blockbuster drugs.

His structural contribution is immense: pioneering a successful, science-driven model for drug discovery that rivals large pharma companies. His wealth is secured by his long-term equity stake in the publicly traded company and the colossal, stable, and continuous profitability of the global specialty pharmaceutical sector.

Dr. Leonard Schleifer's social impact is massive and structural, tied to Regeneron's role in discovering and delivering life-saving treatments for global diseases (oncology, blindness, inflammation). His company's technology is critical to global public health. His personal philanthropy supports various medical research and educational initiatives (including funding the Regeneron Science Talent Search).

His structural contribution is tied to his belief in scientific rigor and long-term investment as the only reliable path to biomedical innovation.

Dr. Leonard Schleifer maintains the professional, composed style of a science-executive. His attire is consistently formal and high-quality, favoring tailored suits. His aesthetic reflects stability and immense intellectual authority, typical of a leader in the specialized biotech sector.

Residing in Chappaqua, New York, his luxury is the immense security and financial reward derived from his multi-billion dollar fortune. His life is dedicated to biotechnology innovation, scientific integrity, and the long-term pursuit of medical breakthroughs.