The Food and Drug Administration is questioning whether the higher of two proposed doses of a Novartis AG (NVS) drug is necessary to treat chronic obstructive pulmonary disease.

Regulators are consulting with outside experts to see whether the dose of 150 micrograms of the drug indacaterol is needed and supported by submitted efficacy data and balancing safety data, according to a report by Reuters, citing analysis by FDA Administration staff.

This is indacaterol’s second review by the FDA. The federal agency rejected the drug in October 2009 and requested more information.

According to a Novartis study, lung function was better after 12 weeks of treatment with either of the two doses compared with the placebo, though the doses were not compared side-by-side.

The drug maker is seeking approval for both doses so that it can move forward with a combination drug that is expected to generate strong sales. But the FDA notes in its analysis that selecting proper dosage is a major safety issue, according to the report.

The panel is set to decide on the dosage Tuesday afternoon. The FDA, which is slated to deliver a final ruling by April 1, historically follows panel recommendations closely.

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