Ashurst has joined Slaughter and May and Linklaters among the line-up of law firms advising on the £46bn takeover of Irish drug company Shire by Japan's Takeda Pharmaceutical.

The successful £46bn bid is the fifth offer put forward by Takeda, and follows a £43bn bid that was rejected by Shire in April.

Ashurst is advising Evercore Partners, JP Morgan and Nomura, the joint financial advisers to Takeda, with a team led by corporate partners Robert Ogilvy Watson and Tom Mercer alongside banking partner Tim Rennie.

Fried Frank also took a role advising Evercore, with a team led by co-head of the firm's mergers and acquisitions practice Philip Richter and litigation partner Scott Luftglass.

Linklaters is advising Takeda on the takeover, with a team including corporate partner James Inglis, alongside global corporate chair Matthew Middleditch, corporate partner Aisling Zarraga and managing associate Sarah Flaherty. Global US practice head Tom Shropshire and Japan corporate partner Hiroya Yamazaki are also advising.

Japanese 'big four' firm Nishimura & Asahi and offshore firm Ogier are also advising Takeda.

Slaughters is acting for regular client Shire, with City corporate partners Martin Hattrell and Christian Boney at the helm. US firm Davis Polk & Wardwell and offshore firm Mourant Ozannes are also advising the Dublin-based company.

The magic circle firm previously took the lead for Shire when it made an unsolicited $30bn approach for rival drug company Baxalta in 2015. The companies completed a $32bn merger the following year, with Hattrell leading the firm's team.

Hattrell also represented Shire on its $5.2bn acquisition of US company NPS Pharmaceuticals in 2015 and when it was the subject of an attempted takeover by US drugmaker AbbVie in 2014.