Takeda Pharmaceutical Co. Ltd has agreed to sell its dry eye drug to Swiss drugmaker Novartis AG for $3.4 billion and potential milestone payments of up to $1.9 billion, in the first divestment since its takeover of the U.K.'s Shire.

Japan's biggest drugmaker aims to dispose of $10 billion worth of assets to cut debt taken on for the $62 billion Shire acquisition sealed in January, which catapulted it into the world's top 10 drugmakers by sales but also made it one of the most indebted.

The sale of Shire's Xiidra dry eye treatment is likely to close in the second half of 2019, Takeda and Novartis said in a statement.