Novel neurokinin 3 receptor antagonist for VMS clears phase II study

Treatment with the neurokinin 3 receptor antagonist GS1-144 appears to help reduce the frequency and severity of vasomotor symptoms (VMS) in postmenopausal Chinese women, according to a phase II study.

The study included Chinese women aged 40 and 64 years who were experiencing moderate-to-severe VMS. These participants were randomly assigned to receive GS1-144 at 30 mg once daily, 60 mg once daily, or 30 mg twice daily or placebo for 12 weeks.

Changes in the frequency and severity of VMS from baseline to weeks 4 and 12 were assessed as the study’s co-primary endpoints.

Of the participants, 271 (98.2 percent) completed 4 weeks of treatment, and 258 (93.5 percent) completed the entire 12 weeks.

A significant reduction in VMS frequency was observed with GS1-144 at the 30-mg twice-daily dosing at week 4 (least squares mean difference, −1.31, 90 percent confidence interval [CI], −2.35 to −0.26; p=0.04) and week 12 (least squares mean difference, −1.41, 90 percent CI, −2.28 to −0.54; p=0.008), as well as with the 60-mg once-daily dosing at week 12 (least squares mean difference, −1.42, 90 percent CI, −2.28 to 0.55; p=0.007) relative to placebo.

In terms of VMS severity, GS1-144 at the 30-mg twice-daily dosing was associated with reductions at week 4 (least squares mean difference, −0.14, 90 percent CI, −0.26 to −0.01; p=0.07) and week 12 (least squares mean difference, −0.24, 90 percent CI, −0.43 to −0.05; p=0.04) compared with placebo. Reductions were also observed with the 60-mg once-daily dosing at weeks 4 (least squares mean difference, −0.13, 90 percent CI, −0.26 to −0.01; p=0.07) and 12 (least squares mean difference, −0.19, 90 percent CI, −0.38 to 0.00; p=0.098) relative to placebo.

Treatment-emergent adverse events occurred in 67.6 percent of GS1-144-treated participants and in 62.3 percent of those who received placebo. No liver safety risks emerged with GS1-144.