Bayer has purchased the European business for Boehringer Ingelheim's blood pressure treatment telmisartan - sold under the brand names Pritor and PritorPlus - from GlaxoSmithKline.
Telmisartan, an angiotensin II receptor blocker, had a turnover in Europe of approximately 65 million euros ($78m) in 2005.
Bayer said the business was attractive because the ARB class has a growth rate of about 15% a year, the fastest growing segment in the European hypertension market.
With this acquisition Bayer Healthcare will gain the right to market the drug in Italy, Spain, France, Greece, Portugal and 22 smaller European markets. The companies have agreed not to disclose the financial terms of the transaction.
Bayer already has a co-marketing agreement with Boehringer Ingelheim under which it promotes telmisartan under the brand name Kinzalmono and Kinzalkomb in other markets across Europe, including Germany, Belgium, the Netherlands, Switzerland and Finland.