Covington & Burling and Latham & Watkins have secured advisory roles on Dublin-headquartered pharmaceutical company Allergan's acquisition of Kythera Biopharmaceuticals in a $2.1bn (£1.3bn) deal.

Latham has been appointed by Kythera to act as its primary counsel on the deal.

The firm's team is being led by Silicon Valley life sciences co-chairs Mark Roeder and Alan Mendelson and corporate partner Josh Dubofsky.

Corporate advice is being provided by partner Brian Cuneo and antitrust matters are being dealt with by San Francisco partner Karen Silverman and Washington DC counsel Sydney Smith.

Covington is acting for Allergan on the deal. Its team is headed by New York corporate partner Andrew Ment.

Partner Mike Francese is advising on employee benefits, co-chair of the food and drug practice Peter Safir is leading on drug regulatory issues and partners Lee Kelley and Rob Heller are advising on tax.

Allergan is the product of a March 2015 deal in which Actavis, a Dublin-headquartered pharmaceuticals company, acquired Allergan, the maker of Botox, in a $66bn (£41.6bn) transaction. The merged company was named Allergan.

Cleary Gottlieb Steen & Hamilton represented Actavis and Latham acted for legacy Allergan on the deal.

The Cleary team was led by corporate partners Victor Lewkow and Paul Shim. They faced off against legacy Allergan's Latham team, which was headed by corporate partners Cary Hyden, Paul Tosetti and Michael Treska.