Mechanism and Promise Behind SPN-830 for Parkinson Disease: Stuart Isaacson, MD, FAAN

WATCH TIME: 3 minutes

"Unlike levodopa, it doesn't need conversion...it has 100% bioavailability...and it has remarkably good tolerability, delivering consistent benefits."

Levodopa is considered the cornerstone treatment for Parkinson disease (PD), offering significant benefits in managing motor symptoms, such as tremors, rigidity, and bradykinesia. While it helps replenish the brain’s dwindling dopamine levels, it has several drawbacks, including inconsistent efficacy due to delayed absorption in the gastrointestinal system, leading to fluctuations in symptom. Over time, long-term use can also result in the development of motor complications, such as dyskinesia and “ON-OFF” phenomena, where patient experience periods of sudden worsening or improvement of symptoms.

In early February, the FDA approved a new therapeutic, a subcutaneous apomorphine infusion device dubbed SPN-830, for the treatment of motor fluctuations in adults with advanced PD. The therapy’s approval was based on the TOLEDO study (NCT02006121), a randomized, double-blind trial that showed a 1.89-hour reduction in OFF time for Parkinson's patients using the device compared to placebo. Published in Lancet Neurology (2018), the study involved 106 patients who received either a 3-mg/hour to 8-mg/hour dose of apomorphine (n = 53) or placebo saline (n = 53) during waking hours for 12 weeks.

As part of NeurologyLive's ongoing coverage of the approval, movement disorder expert Stuart Isaacson, MD, FAAN, sat down to discuss the unique mechanism of SPN-830 in treating PD. Isaacson, director of the Parkinson’s Disease and Movement Disorders Center of Boca Roaton, Florida, provided context on how this new device differs from levodopa, which has variable absorption and relies on a complex process to reach the brain. Notably, he spoke on the bioavailability of this new medication and why its direct action on dopamine receptors make it a significance advancement in PD care.

REFERENCES
1. Supernus Announces FDA Approval of ONAPGO™ (apomorphine hydrochloride) for Parkinson’s Disease. News Release. Supernus. Published Febrauary 4, 2025. Accessed February 6, 2025. https://ir.supernus.com/news-releases/news-release-details/supernus-announces-fda-approval-onapgotm-apomorphine
2. Katzenschlager R, Poewe W, Rascol O, et al. Apomorphine subcutaneous infusion in patients with Parkinson's disease with persistent motor fluctuations (TOLEDO): a multicentre, double-blind, randomized, placebo-controlled trial. Lancet Neurol. 2018;17(9):749-759. doi:10.1016/S1474-4422(18)30239-4