Summit Clinical Research Solutions Expands Pinnacle Site Network With Acquisition of Dallas Research Institute
The LongueVue Capital portfolio company's acquisition deepens its metabolic and liver disease expertise and expands its footprint in the Dallas-Fort Worth metroplex.
NEW ORLEANS, September 10, 2026. LongueVue Capital announced that its portfolio company, Summit Clinical Research Solutions, has acquired Dallas Research Institute. The deal runs through Summit's integrated site network, Pinnacle Clinical Research. It deepens Summit's expertise in metabolic and liver diseases and expands Pinnacle's presence in the Dallas-Fort Worth metroplex.
Dallas Research Institute was founded in 2024 as a joint venture between the late Dr. Stephen Harrison, co-founder of Summit and Pinnacle, and the company. It specializes in complex clinical trials targeting metabolic and liver-related conditions, including MASLD, MASH and obesity. Dr. Pedro Castillo Jr. has served as the site's principal investigator since its inception. He will continue in that role after closing.
"DRI is a natural fit for the Pinnacle site network given its overlapping therapeutic area focus and expands the Company's presence in the desirable DFW metroplex," said Ryan Nagim, managing partner and head of healthcare at LongueVue Capital. "Since its inception, DRI was created consistent with Dr. Stephen Harrison's vision, making this a highly strategic and accretive acquisition."
"From the beginning, it was clear that Summit and Pinnacle share our commitment to conducting high-quality clinical research and delivering exceptional patient care," said Castillo. "We're excited to join an organization that will help us to continue to expand our impact on patients and provide industry leading solutions to sponsors while staying true to the values and culture that have defined DRI to date."
Summit is headquartered in San Antonio, Texas. Its platform spans more than 110 partner sites across eight countries and 15 fully owned sites in the US. LongueVue Capital was founded in 2001 and is a New Orleans-based private equity firm. The firm has more than $1 billion of committed capital across five funds.