Chandra Sekhar (Chandrasekhar) Pemmasani, MD, is the founder and chief executive officer of USMLEWorld LLC.

Born and educated in India, Dr. Pemmasani came to the United States for postgraduate study and founded the company as he began his residency. In 2000, he wrote a 200-page review and study guide for the USMLE examinations, which he took to several publishers, who advised him to return when he had completed his medical training. Dr. Pemmasani instead turned to the Internet and, with the support of family and friends, developed several on-line review products while maintaining his full residency schedule.

Dr. Pemmasani founded USMLEWorld in 2001 and was responsible for most of the initial products. As the number of subscribers grew, the company hired additional physicians and market share increased annually. Seven years after its launch, the company achieved more than 90% market share in this educational segment, exceeding that of Kaplan, Inc. Today, USMLEWorld trains more than 120,000 medical students and residents annually. In 2012, the company instituted educational products for initial certification and recertification examinations for internal medicine physicians.