Merz Neuroscience’s Xeomin has become the first agent to be approved by the US Food and Drug Administration to treat excessive drooling.

Sialorrheam, or excessive drooling, is a common symptom among patients who suffer from neurological disorders including Parkinson's disease, amyotrophic lateral sclerosis (ALS), cerebral palsy (CP) or who have experienced a stroke.

The condition can occur from difficulty retaining saliva inside the mouth, issues with swallowing and from problems controlling facial muscles.

Xeomin is a neurotoxin approved for sialorrheam on the back of Phase III data showing a significant reduction in unstimulated salivary flow rate versus placebo.

The treatment also fared well on tolerability, with the overall frequency of adverse events similar between placebo and treatment groups with no new or unexpected adverse events reported, the firm noted.

"This approval represents a significant milestone in addressing the unmet needs for more than 600,000 adults who suffer from chronic sialorrhea, and underscores our commitment to improving the lives of those living with movement disorders,” noted Kevin O'Brien, vice president and US Head of Neurosciences, Merz North America.

This is the fourth neurological indication for Xeomin, which is already on the market for increased muscle stiffness in the arm of adults with upper limb spasticity, the abnormal head position and neck pain that happens with cervical dystonia in adults, and to treat abnormal spasm of the eyelids (blepharospasm) in adults who have had prior treatment with Botox (botulinum toxin A).