Our work starts and ends with TRUTH and INTEGRITY.

Our Leadership Team

Robert T. Taketomo, Pharm.D., MBA

President and CEO

As a nationally recognized leader in hospital and managed care pharmacy operations, Bob Taketomo launched Ventegra in 2005 to focus on the pharmacy segment of healthcare, with a strong vision and expectation to expand into other healthcare delivery segments. He has more than 35 years of experience as a pharmacist. He started in research as a Clinical Pharmacokineticist, moving into general clinical programs as a Supervisor, Manager, and Director in the hospital environment. He has been involved in managed care for more than a decade, starting with Cigna, FHP, PacifiCare, and Health Net. For FHP and PacifiCare, Bob oversaw all pharmaceutical contracts and implemented purchase, rebate, and risk agreements. As Vice President of Industry Relations, he also launched the generic sampling program, FirstLine Solutions, and the first injectable program (now known as “specialty”) at RxSolutions, the PBM for PacifiCare. In January 2002, Bob joined Health Net of California as Vice President of Pharmacy. In this capacity, he oversaw all pharmacy functions including formulary, benefit design, network management, claims, and prior authorization. He spearheaded Health Net’s injectable initiative which included the consolidation of approximately $50M in injectable purchases into a single preferred pharmacy, and worked with other payors to launch The Generic Advantage program. In January 2004, he assumed pharmacy oversight responsibility for Health Net of Oregon. Bob received his Doctor of Pharmacy from the University of Southern California, and conducted his undergraduate studies at the University of California at Los Angeles. He completed a clinical residency in Pharmacokinetics at the Veterans Administration Medical Center in La Jolla, California. He went on to earn his Master’s of Business Administration from Pepperdine University.


Mariana Ritchie

Vice President, Industry Relations

Mariana Ritchie joined Ventegra in January of 2005, starting as our first “healthcare intern.” With more than 20 years of experience in pharmacy benefit management, pharmaceutical contracting, and retail pharmacy, Mariana is responsible for the company’s Industry Relations. In this role, she bridges the relationship between Ventegra, our clients, and the pharmaceutical industry. Among her accomplishments, Mariana was instrumental in implementing Prescription Solutions’ automated rebate system, and assisting in the development of their generic sampling program and a zip code reporting tool. She has spearheaded the development and implementation of Ventegra’s proprietary Robo-Rebate solution, and has been the lead architect of the company manifesto. Mariana holds a Master’s of Public Health from Loma Linda University and is a California State Board of Pharmacy registered Pharmacy Technician.


Mark S. Shinmoto

Vice President and Chief Pharmacy Officer

Mark S. Shinmoto, PharmD, brings more than 18 years of healthplan and managed care visionary leadership and healthcare industry know-how to his position of Vice President and Chief Pharmacy Officer at Ventegra. He has results-proven experience working with health plans, hospital health systems, PBMs, medical providers and the pharmaceutical industry market segments. Mark has extensive knowledge of health system operations, healthcare policies and compliance, and Commercial and Medicare reimbursement for oral and injectable medications. Mark is an expert in benefit design and formulary considerations. Prior to joining Ventegra, Mark served as Director of Pharmacy for HealthCare Partners (HCP), where he had responsibilities for pharmacy operations and various committees within HCP. Mark was pharmacy co-chair for the CAPG Pharmaceutical Committee and co-chair for the Medicare Pioneer ACO Pharmacy Workgroup Committee. Previous, he was Director of Pharmacy for PacifiCare Health Systems for multiple states nationally, and the Director of Pharmacy Services at RxSolutions, the PBM for PacifiCare. Mark received his Doctor of Pharmacy from the University of Southern California.


Joyce Howie

Vice President, Business Operations

Joyce Howie joined Ventegra in February 2005 and provides leadership in our Business Operations division. Joyce has a rich hands-on background in the pharmacy industry. She began her pharmacy career as a pharmacy technician in 1986 with Cigna Health Plans. Her biggest accomplishment with Cigna was helping launch the prior authorization department. She also received the Pharmacy Technician of the Year award. Joyce continued her pharmacy education at St. Francis Medical Center as the Department Administration Assistant. She learned the methodology around hospital pharmacy while assisting with such areas as P&T Committee and JCAHO accreditation. To round out her experience in the PBM arena, Joyce was a contract analyst for Prescription Solutions. She managed multiple rebate contracts, administering millions of dollars for PacifiCare clients. In 2005, she joined the Ventegra team in the Industry Relations department. In 2010, she transferred over to Ventegra’s Business Operation team. She holds a Bachelor’s of Science degree in Marketing from California State Polytechnic University, Pomona.


David L. Clark

Chief Development Officer

David Clark is a nationally recognized leader in managed care pharmacy and evidence based critical appraisal, and has been involved in managed care clinical services and operations for more than 30 years. He joined Ventegra as Chief Development Officer in 2012. His previous experience includes presidential and other executive leadership roles at well-known health care companies throughout the Western United States. During his career, he has been honored to serve as President and Chair of the Board for the Academy of Managed Care Pharmacy and has been appointed to serve on two federal committees; the Effective Health Care Stakeholder Group, Agency for Agency for Healthcare Research and Quality (AHRQ) and the State Pharmaceutical Assistance Transition Commission, Department of Health and Human Services (HHS). He was also selected to serve as a member of the Blue Cross Blue Shield Association National Council of Physician Executives. He received both his Bachelor’s of Science Pharmacy degree and his Master’s of Business Administration from the University of Utah.