Melevodopa/carbidopa effervescent formulation in the treatment of motor fluctuations in advanced Parkinson's disease

Melevodopa hydrochloride plus carbidopa in effervescent tablets (M/C) is a readily soluble antiparkinsonian tablet formulation. A total of 221 patients with Parkinson's disease and motor fluctuations entered a randomized, double-blind, double-dummy, controlled parallel group study, which compared the effectiveness of oral M/C effervescent tablets with standard oral formulation levodopa/carbidopa tablets (L/C; Sinemet) in reducing total daily OFF time. The difference of total daily OFF time (intention-to-treat population) between the two groups was not statistically significant (P = 0.07): -39.4 minutes (95%CI: -67.08 to -11.73) in M/C group vs. +3.5 minutes (95%CI: -36.19 to +43.26) in the L/C group. In the intragroup analysis, M/C significantly reduced the baseline daily OFF, which remained unchanged in the L/C group. There were no unexpected adverse events in either treatment arms, and discontinuation rates due to adverse events did not differ between the two groups [M/C: 2 patients (1.3%); L/C: 1 patient (1.4%)]. This study failed to meet the primary endpoint (P = 0.07); however, there was a trend in favour of the M/C preparation, which deserves further attention.