Hormonal Effects of the Oral Gonadotropin Releasing Hormone (GnRH) Antagonist at Different Periods of the Menstrual Cycle

What Was Tested

The trial (phase 4) is built around Elagolix (non-peptide).

The purpose of this study is twofold: First, to see if elagolix can suppress gonadotropin and ovarian hormones in the short-term period, when only administered for a 72-hour period.

Second, is there a window for when elagolix functions best?

It had three arms (groups): Early Follicular Phase (experimental), Late Follicular Phase (active comparator) and Luteal Phase (active comparator).

The registry classes the interventions as drug.

More on the Plan

Gonadotropin-releasing hormone (GnRH) and its analogs have been utilized in clinical medicine since the early 1970s.

The GnRH analog is more potent with a longer half-life than native GnRH.

When administered continuously rather than in a more physiologic pulsatile manner, the initial stimulation of pituitary gonadotrophs is followed by pituitary desensitization1,2.

This ultimately leads to inhibition of the pituitary-gonadal axis.

Who Took Part

The registry lists 12 planned participants were the target.

It was open to women only aged from 18 years up to 39 years.

Healthy volunteers could join, not only people with the condition.

Examples of who could join: Healthy volunteers from USC Fertility. Documented ovulation with a serum mid-luteal progesterone ≥3pg/mL. Ovulatory with a 24-35-day cycle. Body Mass Index (BMI) 18.1-30.0kg/m2. Consistent condom use for contraception.

The full record lists 7 inclusion and 2 exclusion criteria; among the exclusions: allergy to injectable or oral gnrh-antagonist.

How the Study Was Run

It was run as a non-randomized, parallel-group and open-label study.

The Elagolix (non-peptide) group and the comparison group ran side by side rather than switching.

Being open-label, the Elagolix (non-peptide) study did not mask who received what.

It started in 2019-10-01 with completion listed for 2020-10-30.

Its stated primary purpose is screening.

What Was Measured

Primary outcome: Suppression of gonadotropin and pituitary hormones as measured by hormonal assay status post short-term administration of elagolix (time frame: measured over 4 days).

It also tracked 1 secondary outcome, for example Time interval to next menses.

What This Means in Plain Language

Put simply, this is a phase 4, non-randomized trial of Elagolix (non-peptide) in 12 people.

Its size is small, so on its own it can only give an early look.

Its status is unknown; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the Elagolix (non-peptide) compound page, all human trials.