CSL's (ASX:CSL) Andembry drug showed a favorable safety and tolerability profile in a phase 3b study in children aged between two and 11 years with hereditary angioedema, a genetic disorder characterized by severe swelling, according to a late Monday statement.

The company said it observed treatment response across the study population, with most of the participants remaining attack-free during the 12-month treatment period.

The topline results support CSL's plan to seek an expanded pediatric indication for Andembry, and the company intends to start submitting filings to health authorities in the first half of its fiscal year.

CSL shares gained 1% in recent Tuesday trade.