Frankfurt : Boehringer Ingelheim, Germany's second-largest drugmaker, posted 11 percent higher sales and a 6 percent gain in operating profit for 2015, boosted by its diabetes treatment business, where it collaborates with Eli Lilly.

Excluding Boehringer's U.S. generics business sold to Hikma Pharmaceuticals Plc at the beginning of this year and the effect of currency swings, sales rose 5.3 percent.

Full-year operating profit rose to 2.3 billion euros ($2.60 billion), on 14.8 billion euros in sales, the unlisted family-owned group said on Tuesday.

The group, which invented mass production of baking powder in the 1890s, said sales at its diabetes portfolio gained a currency-adjusted 49 percent to 1.1 billion euros, with the prospect of driving growth over the long term.

Eli Lilly's new Jardiance diabetes treatment, sold together with Boehringer, earlier this year began stealing market share from rival drugs in its class, bolstered by clinical trials showing it slashed deaths by 32 percent in patients with Type 2 diabetes.

Boehringer said it expected a "minor increase" in sales this year, held back by weak growth in overall pharmaceutical markets, but added it aimed to considerably strengthen its market position.

($1 = 0.8837 euros) (Reporting by Patricia Weiss and Ludwig Burger)