Newron Pharmaceuticals and Zambon’s planned pivotal trial to evaluate a label extension for Xadago (safinamide) in patients with Parkinson’s disease levodopa-induced dyskinesia (PD-LID) is a strategic approach to boost Xadago’s peak sales and strengthen its competitive advantage in the PD space. This strategy usually helps companies to expand their existing patient pool and capitalize on physicians’ familiarity with their brand. Furthermore, the potential label extension will likely grant Xadago an additional three to five years of patent protection, meaning that its patent expiration will not be until 2029 at least.

Sarah Elsayed, Neurology Analyst at GlobalData, comments: “Xadago is currently approved for treating PD ‘off’ episodes. According to Key Opinion Leaders (KOLs) interviewed by GlobalData, as many as one third of PD patients experience PD-LID, and almost all of them will eventually have ‘off’ periods. In fact, it remains one of the major unmet needs in PD. Adamas’ Gocovri (extended-release amantadine) is currently the only drug approved for treating PD-LID in the US, and, given such limited treatment options, PD-LID is considered an orphan indication within PD.”

Notably, Gocovri’s label extension in ‘off’ episodes last month sets an interesting precedent. GlobalData expects that by H2 2023, Xadago could also score an FDA label extension in PD-LID. Therefore, it will be a strong competitor to Gocovri. Both drugs are oral formulations taken once daily and they have been in the US market since 2017. Thus, they have comparable tolerability profiles.

Elsayed continues: “Xadago boasts a lower annual cost of therapy in the US at around $10,109 per patient, compared to $31,135 for Gocovri. Additionally, Xadago currently has a broader pool of PD patients with fluctuating symptoms and ‘off’ episodes compared to Gocovri, which until last month was only approved in PD-LID, a less common complication. As such, GlobalData estimates that Xadago will generate $246m in sales by 2029 in the 7MM, whereas Gocovri sales are forecast to reach $285m by 2029 in the US.”

Elsayed adds: “PD-LID patients suffer abnormality or impairment of voluntary movement, a typical complication seen in moderate-advanced PD patients on levodopa combination therapy. Effective treatments for PD-LID and ‘off’ episodes remain an ongoing challenge in PD treatment. Several companies need to explore alternative strategies to address this unmet need in the PD pipeline.”

* 7MM: seven major markets (The US, France, Germany, Spain, Italy, the UK and Japan).