The takeover marks the latest example of merger-and-acquisition activity in the global healthcare industry, with Pfizer this week buying a stake in French gene therapy firm Vivet while earlier this year Roche bought Spark Therapeutics for $4.3 billion.

Waypoint, which already owns around 83 percent of Stallergenes, will offer 37 euros in cash, representing a 42.9 percent premium to Stallergenes' closing price of 25.90 euros on March 20.

"Waypoint continues to recognise and value Stallergenes Greer as a leader in the development and marketing of allergy immunotherapy treatments (AIT)," Waypoint said in a statement.

"However, in light of Stallergenes Greer's limited public float, Waypoint has concluded that the benefits of having shares publicly listed are limited, and the costs of maintaining such listing are not justified for shareholders," it added.

The Bertarelli name is most closely associated with the global biotechnology firm Serono, which was sold to Germany's Merck in 2007, while Ernesto Bertarelli is also well-known in yachting circles via his involvement in the America's Cup.

Investment bank UBS advised Waypoint on the deal while Evercore advised Stallergenes.

(Reporting by Sudip Kar-Gupta; Editing by Christopher Cushing)