United Therapeutics Corp. (NASDAQ:UTHR) is acquiring is acquiring California-based SteadyMed in a transaction valued at $216 million. SteadyMed, (NASDAQ:STDY) stock shot up 80 percent in premarket trading to $2.65 a share on the news Monday.

Based in Silver Springs, MD, United Therapeutics has a large facility in Durham. The company focuses on developing and commercializing products for otherwise unmet needs of patients with chronic and life-threatening conditions.

SteadyMed, is also focused on drug products for unmet medical needs. It’s lead product is Trevyent, a combination drug-device that combines the company’s PatchPump technology with treprotinil, a treatment for pulmonary arterial hypertension (PAH).

“We are optimistic about acquiring SteadyMed and adding Trevyent to our pipeline of products to treat PAH,” said Martine Rothblatt, chair and CEO of United Therapeutics in a statement.

The deal gives SteadMed $4.46 per share in cash at closing and an additional $2.63 per share upon achieving a milestone in commercialization of Trevyent.

United Therapeutics stock was down 47 cents to $110.40 in premarket trading.