Objective:

To understand the distribution of daily doses of IPX203 in a phase 3 clinical study in Parkinson’s disease (PD) patients exposed for at least 12 months, in terms of the doses that patients took most frequently (modal dose), and treatment emergent adverse events (TEAEs) by modal dose.

Background:

PD patients require a wide range of daily CD-LD doses and it is important to demonstrate safety and tolerability across the recommended dose range. IPX203 is a novel extended-release oral CD-LD formulation.

Design/Methods:

RISE-PD was a randomized, double-blind, phase 3 study evaluating the safety and efficacy of IPX203 vs IR CD-LD in PD patients with motor fluctuations. Patients underwent a 3-week open-label IR CD-LD dose adjustment, a 4-week open-label conversion to IPX203, followed by randomization to a 13-week double-blind treatment with IR CD-LD or IPX203 and was followed by a 9-month open-label extension study. Modal dose was calculated for patients who were exposed continuously for at least 12 months.

Results:

179 patients were exposed to IPX203 continuously for at least 12 months. Patients took a wide distribution of doses, with modal doses ranging from 140/560 mg CD-LD to 1260/5040 mg CD-LD a day. When these 179 patients were grouped into 4 quartiles, with approximately 45 patients in each quartile, modal dose ranges were 560-<1050, 1050-<1470, 1470-<2100 and 2100-5040 mg LD/day. When comparing the number of patients with TEAEs by duration of exposure, data showed that there was a decrease as the exposure time increased, at any modal dose range.

Conclusions:

Data evaluating the safety profile of IPX203 by modal dose range and duration of exposure showed there is no increased safety risk with regard to the number of patients with a TEAE when IPX203 is taken for extended periods of time at the highest modal dose range.