LONDON (Reuters) - GlaxoSmithKline's (>> GlaxoSmithKline plc) new injectable asthma drug Nucala has been recommended for use in Britain's state-run health service in the most severe patients, after the drugmaker provided further analyses on its use and made an additional price cut.

The National Institute for Health and Care Excellence (NICE) initially declined to endorse the antibody treatment as evidence presented by GSK suggested it would be used in less severe cases and would not be cost effective.

The latest draft guidance from NICE, published on Thursday, now backs the medicine for the sickest patients with high levels of white blood cells called eosinophils. The U.S. Food and Drug Administration made a similar ruling earlier in the month.

The drug is designed to lower the level of eosinophils, too many of which can cause lung inflammation.

Nucala is given by injection every four weeks. Its list cost is 840 pounds ($1,050) per dose but the price the National Health Service will pay is confidential.

NICE is also appraising Teva Pharmaceutical Industries' (>> Teva Pharmaceutical Industries Limited) rival biotech drug Cinqaero for severe eosinophilic asthma and has asked Teva to provide more information on cost-effectiveness.

(Reporting by Ben Hirschler Editing by Jeremy Gaunt)