Shares of Japan’s Chugai Pharmaceutical have risen to a record high following reports Swiss drug giant Roche is looking to take control of the company.Chugai’s stock surged by more than 20% in Tokyo trading on Monday.

Roche, the world’s biggest maker of cancer drugs, already owns about 60% of the Japanese firm and is said to be looking to buy the remainder for about $10bn (£6bn).

According to various news outlets, a deal could come as early as this week.

Chugai has denied talks with Roche, saying in a statement made over the weekend that it was “in no way in the process of reviewing any plan to become a wholly owned subsidiary of Roche.”

Roche has owned a majority stake in Chugai, which develops oncology and arthritis drugs, for more than decade.

A successful acquisition of the Tokyo-based firm would add to the wave of global deal-making the pharmaceutical, biotech and medical products sector has seen this year.

According to Mergermarket, more than $260bn in deals were made in the first half of this year as drugmakers looked to reduce costs and find new sources of growth.