Alexza Pharmaceuticals will be acquired for £0.62 ($0.90) per share in cash by Ferrer Pharma, a wholly-owned subsidiary of Grupo Ferrer Internacional (Ferrer)
In addition to the upfront cash payment, Alexza stockholders will be granted contingent value rights to receive cash payments in four payment categories if specified milestones are achieved following the closing.
The transaction is expected to close in the second quarter of 2016 and is subject to customary closing conditions.
The £0.62 ($0.90) per share cash consideration represents a 210% premium to Alexza's closing share price on February 26, 2016, the last trading day prior to the announcement.
Thomas King, president and CEO of Alexza, said: "We see Ferrer as the ideal company to acquire Alexza as we continue to strive toward global commercial success with Adasuve and to re-energise our Staccato-based product pipeline.
"Over the past four years, we have come to appreciate their professionalism, passion, dedication and commitment to Alexza's technologies, products and people.
“With this combination, we feel that Alexza's products will be well positioned for long-term success in serving important patient needs."
Jordi Ramentol, CEO of Ferrer, said: "We are pleased that Alexza will be part of Ferrer and we look forward to working with our new Alexza colleagues.
“We firmly believe that the Staccato technology will change the lives of patients with severe mental and neurological disorders.
“At the same time it will help healthcare professionals to improve their management in the increasingly digitalised and personalised healthcare context."