Duration of benefit per Dose: Carbidopa-Levodopa immediate release vs. extended release capsules (Rytary®)

For patients with Parkinson's disease, clinicians commonly assess duration of benefit for individual doses of levodopa in order to consider medication changes.

To determine the mean duration of ON time per dose and mean duration of ON time without troublesome dyskinesia (WoTD) per dose of CD-LD IR vs. CD-LD ER in the ADVANCE-PD trial.

We performed a post hoc analysis of the ADVANCE-PD trial. Mean ON time per dose and ON time WoTD was calculated at baseline and end-of-study (EOS). Changes were compared between CD-LD IR and CD-LD ER (Rytary®) treatment groups using an ANCOVA model.

Mean (SD) baseline ON time per dose of CD-LD IR (n = 393) was 2.20 h. Patients randomized to double-blind treatment with CD-LD IR (n = 192) experienced an increase in mean ON time per dose from baseline to EOS from 2.24 h to 2.38 h. In comparison, patients randomized to double-blind treatment with CD-LD ER (n = 201) experienced an increase in mean ON time per dose from baseline (on CD-LD IR) to EOS (on CD-LD ER) from 2.17 h to 3.55 h. Conversion and optimization with CD-LD ER increased ON time per dose by 1.21 h more than optimization of CD-LD IR (p < 0.0001). Similarly, CD-LD ER increased ON time WoTD per dose by 1.16 h more than CD-LD IR (p < 0.0001).

In the ADVANCE-PD trial, CD-LD ER significantly increased ON time per dose compared to CD-LD IR (+1.21 h, p < 0.0001) and provided significantly more ON time per dose (3.55 h vs 2.38 h, p < 0.0001).