Title:Design and Development of a Novel Supportive Care Product for the Treatment of Sialorrhea in Parkinson’s Disease
Volume: 15
Issue: 10
Author(s): Neal M. Farber, Santiago Perez-Lloret and Elkan R. Gamzu
Affiliation:
Keywords:
Anticholinergics, Clinical study, Drooling, Drug delivery, Parkinson’s, Sialorrhea, Thin strips, Tropicamide.
Abstract: Sialorrhea or excessive drooling is a significant medical issue in Parkinson’s disease (PD) and neurodegenerative
disorders, although it is often underreported by patients. Sialorrhea affects a large proportion of PD patients, ranging
up to 78% in advanced stages, with many PD patients considering drooling as their worst non-motor symptom. Sialorrhea
affects up to a million patients with diverse neurological impairments, including cerebral palsy, amyotrophic lateral sclerosis
(ALS), Huntington’s, survivors of stroke and severe traumatic brain injury. Numerous approaches have been attempted
to treat sialorrhea in PD patients, including surgical procedures, prosthetic devices, botulinum injections, systemic
anticholinergic drugs, and speech and behavioral therapy. A novel drug treatment (NH004) to control the symptoms
of sialorrhea is under development. The active ingredient is the anticholinergic drug tropicamide. Anticholinergic drugs
work by blocking acetylcholine muscarinic receptors and ultimately decreasing saliva secretion via the reduction of parasympathetic
autonomic nervous system activity. The tropicamide is delivered in a thin film designed to adhere to the buccal
mucosa and to slowly dissolve within the oral cavity, allowing the drug to reach the underlying salivary gland. A pilot
study testing NH004 in PD patients has suggested a potentially useful sialorrhea-reducing effect with NH004 compared to
placebo. The advantages of NH004 include local bioavailability with low systemic exposure, rapid onset of action and,
importantly, convenience of use for patients. This review summarizes the current knowledge and impact of sialorrhea as a
common non-motor symptom in PD, treatment options, the anticholinergic drug tropicamide, the design and development
of the thin film drug delivery system, and NH004 for the treatment of sialorrhea.
