The London-listed firm is one of several companies that had been trying to make generics of GlaxoSmithKline’s former respiratory diseases blockbuster for the US market.
Advair (fluticasone+salmeterol) is approved to prevent flare-ups or worsening of chronic obstructive pulmonary disease (COPD) and prevent asthma attacks.
It propped up sales at GSK for years after patents expired because of delays developing cheaper copycats in the US, where the FDA has tough rules for drug/device combination products such as asthma inhalers.