Background: The efficacy and tolerability of the new micronized purified flavonoid fraction (MPFF) 1000 mg once-daily chewable formulation in comparison with the established MPFF 500 mg conventional tablet at the same daily dose are unknown.
Methods: CHEWY was an international, multicenter, double-blind, double-dummy, randomized, parallel group, non-inferiority phase III study conducted in adult patients with symptomatic chronic venous disease (CVD). Patients were randomly allocated to MPFF 1000 mg chewable or MPFF 2x500 mg daily treatment. The primary efficacy endpoint for clinical non-inferiority (non-inferiority margin predefined at 1 cm) was lower limb discomfort (LLD) assessed by a 10 cm electronic visual analog scale (eVAS) at 8 weeks. Secondary endpoints included leg pain (LP), leg heaviness (LH), and quality of life (QoL) measured by the eCIVIQ-14 questionnaire. Overall acceptability was assessed at each visit by patient and investigator.
Results: Three hundred and nine patients were randomized to MPFF 1000 mg chewable and 302 to MPFF 2x500 mg. After 8 weeks, LLD decreased from baseline by -3.6±2.4 cm and -3.6±2.5 cm in the MPFF chewable and 2x500 mg groups, respectively. Non-inferiority of the once-daily chewable formulation compared with twice daily tablets on improving LLD was demonstrated (adjusted between-group difference [Standard Error]) (E [SE]) = 0.00 (0.18) cm, 95%CI -0.35; 0.35, non-inferiority P value <0.0001. Decreases of similar magnitude were observed at 8 weeks for LP and LH in both treatment arms: -3.4±2.3 cm and -3.5±2.5 cm, respectively for LP, and -3.5±2.5 cm and -3.5±2.6 cm, respectively for LH. QoL (global score) improved by -21.0±17.2 and -22.5±20.1 in the MPFF 1000 mg chewable group and 2x500 mg groups, respectively (E [SE]=1.03 [1.20], 95%CI [-1.32; 3.38]), with similar improvements in the QoL subscore components in both groups. Treatment acceptability was high for both patients and physicians and tolerability similar to the tablet formulation.
Conclusions: MPFF 1000 mg chewable was non-inferior to MPFF 2x500 mg tablets with respect to its effect on LLD. Both formulations were associated with improvements of similar magnitude in lower limb symptoms and QoL. The chewable formulation was observed to be well tolerated and well accepted. Once-daily MPFF chewable tablet offers patients with CVD a good alternative treatment regimen.