Potential first-to-market long acting levodopa combo from Impax/GSK shows promise in PD
This article was originally published in Scrip
Executive Summary
Impax and GlaxoSmithKline have announced that IPX066 has demonstrated a statistically significant improvement over carbidopa-levodopa plus entacapone in reducing the percentage of “off-time” in the ASCEND-PD Phase III trial of Parkinson’s disease patients (Scripintelligence.com, 15 August, 2011). The strength of the extended release cabidopa-levodopa formulation lies in its increased "off time" compared to immediate-release formulations, reduced motor symptoms, and less frequent administration. However, the pricing strategy for IPX066 will have a critical bearing on the drug’s commercial success.
Impax and GlaxoSmithKline have announced that IPX066 has demonstrated a statistically significant improvement over carbidopa-levodopa plus entacapone in reducing the percentage of “off-time” in the ASCEND-PD Phase III trial of Parkinson’s disease patients (Scripintelligence.com, 15 August, 2011). The strength of the extended release cabidopa-levodopa formulation lies in its increased "off time" compared to immediate-release formulations, reduced motor symptoms, and less frequent administration. However, the pricing strategy for IPX066 will have a critical bearing on the drug’s commercial success.
Results of the study found that treatment with IPX066 led to a 33.5% decrease in “off time” compared to a 10% decrease for CLE. As such, IPX066 led to an 84 minute improvement in “off time” over CLE therapy without troublesome dyskinesia. “Off time” is the functional state when patients’ medication effect has worn off and there is a return of motor symptoms.
Reducing motor complications represents one of the most pressing unmet needs in the management of Parkinson’s disease. As the disease progresses, it becomes increasinglis y difficult to control the symptoms adequately, with studies suggesting that almost 40% of patients treated with levodopa therapy for 4–6 years are likely to suffer dyskinesias.
Consequently, Datamonitor believes that the key benefit of IPX066 its ability to rapidly attain and maintain steady levodopa concentrations in the therapeutic window, unlike immediate-release carbidopa/levodopa formulations where patients still experience an average of 5–8 hours of Off time during waking hours. Differentiating IPX066 from existing immediate-release carbidopa/levodopa formulations by addressing the key unmet need of motor fluctuations will be key to its success.
Additional clinical benefits of IPX066 are its reduced pill burden and comparable safety profile to cabidopa/levodopa. The results of the ASCEND-PD study are in line with positive top-line results of the Phase III APEX-PD study announced in November 2010. Impax plans to submit these Phase III data as part of IPX066’s NDA to the FDA, which is planned for late 2011.
Such encouraging Phase III data bode well for regulatory approval of IPX066 in Parkinson’s disease, with Datamonitor expecting US and EU launch to take place in 2012. Upon EU launch, IPX066 is to be commercialised by GlaxoSmithKline, a company which has experience in the Parkinson’s disease market through Requip (ropinirole). As such, GlaxoSmithKline’s prior experience in the market, along with its substantial sales and marketing capabilities will aid market penetration of IPX066. However, due to the highly genericised nature of the carbidopa/levodopa market, the major challenge for Impax/GlaxoSmithKline is to convince payers that IPX066 is cost-effective.
Datamonitor forecasts seven major market revenues of IPX066 to peak at $160 million in 2019.
Charlotte Mackey is a senior healthcare analyst at Datamonitor