Three top officials at the Texas Medical Center have left, the TMC confirmed.

Shawn Cloonan, chief operating officer and executive vice president; Dr. Arthur “Tim” Garson, head of the health policy institute; and Ryan Holeywell, the head of public relations, departed the TMC in recent weeks.

TMC spokesperson Mark Sullivan said that the resignations of Garson and Holeywell were unrelated to to Cloonan’s departure.

Garson left for a consulting job, while Holeywell moved to the East Coast for a health policy position. The TMC declined to comment on the reason for Cloonan’s departure.

Garson joined the TMC in 2014 and focused on health policy. He said in an email that his last day will be Dec. 31.

“It has been a phenomenal 5½ years, but it is the right time to move on,” Garson said. He declined to comment further about the reasons for his departure.

Before TMC, according to a staff biography, Garson worked at the University of Virginia as the director of the center for health policy, the provost, and a professor. While at UVA, he founded the Batten School of Leadership and Public Policy.

Before that, he had a long career in public health policy consulting for Texas’ state health department and other government entities, as well as working at various education and medical institutions including Duke University, Baylor University and Texas Children’s Hospital.

Conversation with Dr. Garson: Has the time arrived for universal health coverage in the U.S.?

Holeywell, who resigned from the TMC in November, could not be reached for comment.

Cloonan, who departed in December, also could not be reached for comment.

Cloonan, who has served as the COO since 2017, started at the TMC in 2013 as the organization’s general counsel. Previously, he was a public finance lawyer representing health care, governmental and higher education clients for Vinson & Elkins LLP and Bracewell LLP, two Houston law firms.

The TMC will replace Cloonan’s position with two new executive roles rather than one COO position, Sullivan said, due to the changing needs of its TMC3 project, a planned biomedical research campus in Houston. The TMC expects to fill those roles in January.

The Texas Medical Center is undergoing a massive redesign of the 37-acre biomedical research project between Brays Bayou and Old Spanish Trail. The $250 million campus, TMC3, aims to establish Houston as an international hub for biomedical innovations, bringing together member institutions to one space.

On HoustonChronicle.com: Texas Medical Center redesigns massive TMC3 project

In May, officials said the locations of some of the planned buildings would be shifted. The campus is dubbed “3” for the “third coast for life sciences,” and is expected to open as early as 2022.

Top centers of biotechnology are on the East and West coasts, in places such as Boston, San Diego and Silicon Valley.

The TMC3 is a collaborative effort of the Medical Center, Baylor College of Medicine, Texas A&M University Health Science Center, University of Texas Health Science Center at Houston (UTHealth) and University of Texas MD Anderson Cancer Center.

The article was updated Thursday to reflect the correct departure date of Holeywell. He resigned in November, not December, as the TMC had initially confirmed.

The article was updated to include further statement from the TMC regarding executive positions to be filled in January.

Jenny Deam contributed to this report.

erin.douglas@chron.com

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