As he approaches the first anniversary of his appointment as chief executive of GlaxoSmithKline, Andrew Witty can look back on a year that has combined smooth consistency in strategy with energetic disruptiveness in tactics.

The purchase of Stiefel Laboratories for up to $3.6bn (£2.5bn) is the largest deal he has yet conducted. But it is in line with an approach of “grow, deliver and simplify” outlined internally (when he was competing for the top job against two rivals) and externally once he formally took over last June.