Imprivata, the Lexington, Massachusetts-based developer of health IT security tools, has agreed to be acquired by an affiliate of Thoma Bravo, a San Francisco private equity firm. The deal is valued at approximately $544 million.

"We are now in a stronger position to pursue market opportunities through innovating and expanding the products and services we offer," said Omar Hussain, president and CEO of Imprivata, who noted Thoma Bravo's experience working with security and healthcare IT companies.

"The Imprivata security platform provides mission critical technologies that are deeply embedded within the daily workflows of the world’s largest and most prestigious hospitals and healthcare institutions," said Chip Virnig, a principal at Thoma Bravo, in a statement.

"The need to combine strong, compliant security technology with ease of access in the healthcare industry is growing by the day," added Thoma Bravo Managing Partner Scott Crabill.

Under the terms of the agreement, shareholders of record will receive $19.25 in cash per share of Imprivata common stock - a 33 percent premium to Imprivata’s last closing stock price of $14.50.