DLA Piper, Nabarro and King & Wood Mallesons (KWM) are among the firms that have advised a clutch of pharmaceutical companies, including GlaxoSmithKline (GSK), as they were fined £45m. 

GSK has been fined alongside a raft of other pharmaceutical firms for paying rival drug makers to delay the release of their competing drugs into the UK marketplace between 2001 and 2004.

The Competition and Markets Authority (CMA) ruled that the payments from GSK broke competition rules and "potentially deprived the NHS of the significant price falls that generally result from generic competition".

Nabarro has advised pharmaceutical giant GSK which was hit with a £37.6m fine.

The firm's team was led by competition partner Brian Sher. The firm also instructed Brick Court Chambers' James Flynn QC on the case and was supported by economist Charles River Associates.

The firm has advised GSK on competition issues before. Sher led a team working on the competition aspects of its acquisition of Maxinutrition in 2010. On that deal Slaughter and May advised GSK on corporate law and Macfarlanes acted for the seller of Maxinutrition Darwin Private Equity.

DLA Piper advised pharmaceutical company Merck group, the parent company of Generics UK, one of the companies that received payments from GSK, as it was handed a fine of £5.8m in the case.

The firm's team on the case includes London competition partner Kate Vernon, Brussels competition partner Bertold Bar-Bouyssiere and Frankfurt antitrust partner Michael Holzhauser.

The other pharmaceutical company that received payment for its delay into the market, Alpharma, received fines totalling £1.5m. This fine is being shared between three companies Activis UK, Xellia Pharmaceuticals and Alpharma, due to changes in ownership.

Activis turned to King & Wood Mallesons joint head of life sciences & healthcare Cameron Firth for advice on the case.

Xellia declined to comment on its legal advisers. Alpharma has been approached for comment.

Michael Grenfell, the CMA's executive director for enforcement, said that the companies' behaviour was "designed to stifle competition at the expense of customers – in this case, the NHS and, ultimately, taxpayers".

GSK is set to appeal the ruling.