THL Partners has agreed to acquire a majority stake in Celerion, a Nebraska-headquartered clinical research organization specializing in early-phase clinical pharmacology and bioanalytical sciences, from H.I.G. Capital for approximately $1.8 billion.
Founded by Dr. Susan Thornton in 2010 from the clinical business of MDS Pharma Services — itself tracing its history to Harris Laboratories’ first clinical trial in Lincoln in 1969 — Celerion specializes in first-in-human dose escalation, cardiac safety, bioequivalence, and drug-drug interaction studies. The company operates clinical research units and bioanalytical laboratories in Nebraska, Arizona, Switzerland and Ireland, employs more than 1,000 people, and has conducted more than 6,000 clinical studies.
H.I.G. acquired the company in November 2022. THL will invest through Fund IX, its 2021-vintage flagship fund that closed at $5.6 billion. The transaction is expected to close in 2026.
THL, headquartered in Boston, invests in middle-market healthcare, financial technology, and technology companies with more than 25 years of pharma services investment experience. Megan Preiner and Joshua Nelson led the THL deal team.
