Validation and Application of Thresholds to Define Meaningful Change in Vasomotor Symptoms Frequency: Analysis of Pooled SKYLIGHT 1 and 2 Data

Vasomotor symptoms (VMS), the characteristic symptoms of menopausal transition, are often the primary reason women seek treatment. Current treatment options for VMS include fezolinetant, a nonhormonal, selective neurokinin 3 receptor antagonist. This study aimed to define a clinically meaningful threshold for reduction of moderate-to-severe VMS in postmenopausal women treated with fezolinetant and then apply it in a responder analysis of the pooled trial data. This analysis pooled data from two identical phase 3, double-blind, placebo-controlled studies that randomized women with moderate-to-severe VMS to once-daily fezolinetant 30 mg, 45 mg, or placebo (SKYLIGHT 1 and 2). The frequency of VMS was collected daily using an electronic diary. Patients completed the Patient Global Impression of Change in VMS (PGI-C VMS) instrument, which assessed changes in hot flushes/night sweats at weeks 4 and 12 compared with baseline using a seven-point Likert scale. VMS frequency data were anchored to PGI-C VMS data; the anchor level for meaningful within-patient change in PGI-C VMS was "moderately better." In the pooled population (N = 1022), the mean (standard deviation) estimated thresholds for a meaningful within-patient change in moderate-to-severe VMS frequency were - 5.73 (3.47) at week 4 and - 6.20 (5.18) at week 12. Applying the thresholds for meaningful within-patient change to responder analyses ("missing as non-responder" imputation method) indicated a favorable clinical benefit: greater proportions of responders were observed in the fezolinetant 30-mg and 45-mg groups compared with placebo at week 4 (odds ratio range 2.48-2.91; P < 0.001) and week 12 (odds ratio range 1.908-2.68; P < 0.001). PGI-C VMS is sensitive to change and correlates with VMS frequency: a reduction of approximately six VMS episodes per day from baseline to week 12 was meaningful at the individual patient level. Fezolinetant provides a meaningful clinical benefit for women with moderate-to-severe VMS associated with menopause and represents an important nonhormonal treatment option. NCT04003155 and NCT04003142.