Safinamide May Reduce Nonmotor Symptoms in PD, Study Says

Safinamide belongs to a class of drugs called monoamine oxidase type B inhibitors and is used in conjunction with levodopa to manage OFF periods.

Treatment with safinamide 50 mg may significantly reduce nonmotor symptoms in patients with Parkinson disease (PD), according to a recent study.

Safinamide is approved as an add-on treatment in PD for patients taking levodopa and carbidopa to treat OFF phases. It belongs to a class of drugs called monoamine oxidase type B (MAO-B) inhibitors and works by increasing the amount of dopamine.

Continued levodopa use may lead to motor and nonmotor fluctuations. This longitudinal prospective study, conducted in Italy, sought to determine if safinamide 50 mg may improve nonmotor, cognitive, and behavioral symptoms over 6 months of treatment.

Nonmotor symptoms in PD, including cognitive impairment, psychiatric symptoms, sleep disorders, autonomic dysfunction, pain, and fatigue are undertreated, the researchers noted.

The study was conducted from January 2018 to April 2018 in 20 patients with midstage PD. Patients were included if PD developed after the age of 40, had motor fluctuations in OFF periods more than 1.5 hours a day, and had stable dopaminergic treatment in the last 30 days.

More than half (55%) of the patients were male, with a mean age of 63.8.

The researchers assessed clinical features using numerous validated PD-specific scales, including the modified Hoehn and Yahr stage and the Unified Parkinson’s Disease Rating Scale (UPDRS) part III during an on period. In addition, the presence of treatment-related motor complications was assessed by means of the UPDRS part IV.

Nonmotor symptoms were assessed using the Non-Motor Symptom Scale (NMSS). Patient-reported quality of life was evaluated using the Parkinson's Disease Questionnaire 39. The presence and severity of treatment complications were checked with the Wearing-off questionnaire 19 and the Abnormal Involuntary Movements Scale.

Neuropsychological and behavioral assessments were conducted during on periods at baseline and again at 6 months. Global cognitive functioning was checked with the Montreal Cognitive Assessment and the PD Cognitive Rating Scale.

Symtpms of depression, anxiety, autonimic dysfunction, sleep disturbances, impulsive compulsive disorders, pain, apathy, and fatigue were also assessed.

After the baseline assessments, all patients began taking safinamide 50 mg daily, with patients already taking other MAO-B inhibitors switching. After 6 months of therapy, clinical features were rexamined by the same providers.

Compared with their condition at the start of the study, the researchers found significant improvement at the 6-month mark in interest, motivation, apathy, fatigue, and urinary symptoms, according to the NMSS scale.

Neuropsychiatric assessment showed a significant decrease in fatigue and apathy scores, and motor assessment revealed a significant reduction in the total wake-up time spent in the OFF phase.

However, there was no change in global cognitive functions at 6 months or in pain scores.

The study showed that nonmotor and behavioral PD-related symptoms may benefit from even the lowest dose of safinamide, the authors said, possibly due to the drug's neurotransmitter receptor-binding profile. However, more studies are needed to confirm the effect.

Reference

De Micco R, Satolli S, Siciliano M, et al. Effects of safinamide on non-motor, cognitive, and behavioral symptoms in fluctuating Parkinson’s disease patients: a prospective longitudinal study. Neurol Sci. 2022;43(1):357-364. doi:10.1007/s10072-021-05324-w