Descendants of the founder of Japanese drugmaker Takeda are set to make a final attempt on December 3 to prevent its 49-billion-pound takeover of Shire, reported The Times.

Kazu Takeda, a leading member of the family, plans to hold a press conference in an attempt to persuade retail investors to block the planned acquisition, which a group of dissident shareholders, made up of family members and former employees, says will have "disastrous" consequences.

Shareholders will be asked to vote on the deal on December 5, and Takeda needs 75-percent support for the issue of new shares to finance the acquisition.

According to the news source, if the acquisition moves ahead, it will make Takeda one of the most indebted drugmakers in the world, with borrowings set to reach five times earnings.

The proposed acquisition of Shire by Takeda has already been cleared by regulators in Japan and the US, and last month also gained approval from the European Commission.