Effects of E2/P4 oral capsules on bone turnover in women with vasomotor symptoms

Objective:
To evaluate bone turnover markers (BTM) in the REPLENISH trial (NCT01942668).

Methods:
REPLENISH evaluated oral estradiol/progesterone (E2/P4) for the treatment of moderate to severe vasomotor symptoms (VMS) in postmenopausal women with a uterus. Eligible women for this analysis had ≥50 moderate to severe VMS/wk, were <5 years since last menstrual period, and had BTM measurements at baseline, and months 6 and 12. Percent changes for three BTM (bone-specific alkaline phosphatase [BSAP], C-terminal telopeptide of type I collagen [CTX-1], and N-terminal propeptide of type I procollagen [P1NP]) assessed by immunoassay methods were evaluated from baseline to months 6 and 12 for the 1 mg E2/100 mg P4, 0.5 mg E2/100 mg P4, and placebo groups.

Results:
A total of 157 women (40-61 y, 69% White) were analyzed. Mean baseline values ranged from 14.0 to 14.3 U/L for BSAP, 0.34 to 0.39 ng/mL for CTX-1, and 76.9 to 79.3 ng/mL for PINP. Mean differences in percent change from baseline for both E2/P4 doses versus placebo significantly decreased at months 6 and 12 and ranged from −8% to −16% for BSAP (all, P < 0.05), −30% to −41% for CTX-1 (all, P ≤ 0.001), and −14% to −29% for PINP (all, P < 0.01).

Conclusions:
REPLENISH data provide support for a potential skeletal benefit of E2/P4 when it is used for the treatment of moderate to severe VMS. Further studies are warranted.