Boston-based private equity firm THL Partners has agreed to acquire Celerion from H.I.G. Capital in a transaction valued at $1.8 billion. The deal represents one of the largest healthcare-focused buyouts announced this year and underscores continued investor appetite for clinical research and bioanalytical services platforms.

Celerion, founded in 2010 and headquartered in Lincoln, Nebraska, provides clinical pharmacology and bioanalytical sciences to pharmaceutical and biotech clients worldwide. THL, which has invested in healthcare for five decades, typically targets middle-market companies with enterprise values between $250 million and $2.5 billion across its core sectors.

Miami-based H.I.G. Capital, which acquired Celerion, maintains a broad healthcare practice spanning provider services, hospital facilities and life sciences. The transaction is expected to close later this year, pending regulatory approvals and customary closing conditions.