Takeda Pharmaceutical Co. agreed to buy closely held Nycomed for €9.6 billion (¥1.12 trillion), the largest takeover by a Japanese drugmaker, broadening its reach in emerging markets and adding a remedy for smokers' cough to its portfolio.

Asia's largest pharmaceutical company will pay cash for Zurich-based Nycomed, which is controlled by Nordic Capital and Credit Suisse Group AG's private equity unit, Osaka-based Takeda said in a statement Thursday. The purchase price includes €3.6 billion of net debt.

Nycomed, which gets more than a third of its revenue from emerging markets, will reduce Takeda's reliance on sales in Japan and the United States.