Single Dose of Vyleesi in Lactating Female Subjects to Measure the Concentration of Bremelanotide in Breast Milk

What Was Tested

In this phase 4 trial, researchers set out to test PT-141 (Bremelanotide).

The maximum duration of subject participation in the study will be approximately 29 days, consisting of 3-week Screening period, a 1 day treatment period, and up to a 7 day follow-up period.

It had 1 arm (groups): Vyleesi (experimental).

The registry classes the interventions as drug.

Who Took Part

Enrollment: 10 actual participants took part.

It was open to women only aged from 18 years up to 55 years.

Healthy volunteers were not accepted; participants needed the condition being studied.

Examples of who could join: Female subjects ≥18 to 55 years of age (inclusive) and premenopausal. Lactating, between 10 days and 6 months postpartum (inclusive). Exclusively breastfeeds their infant prior to participation in the study. Ensure at the time of screening that the breastfed infant can feed from a bottle during maternal participation in the study. The subject is not pregnant, and does not intend to become pregnant before, during, or within 1 complete menstrual cycle or 2 months after administration of study drug.

The full record lists 7 inclusion and 4 exclusion criteria; among the exclusions: breastfeeding is not well established in the mother-infant pair (e.g., poor latching of the infant or low milk supply); has used any investigational compound and/or an experimental medical device within 28 days before screening; has taken bmt within 24 hours of participation in the study.

How the Study Was Run

The set-up was single-group and open-label.

Nothing was hidden in this open-label PT-141 (Bremelanotide) study: the participants and staff both knew the treatment.

Everyone received the same intervention, so there was no separate comparison group inside the trial.

It started in 2025-07-11 with completion listed for 2025-11-15.

It ran at 1 site in United States.

Its stated primary purpose is treatment.

What Was Measured

The main thing measured (primary outcome): Levels of Bremelanotide (BMT) in Breast Milk Over 24h After Administration of Vyleesi (time frame: 24 hours). Maximum observed concentration (Cmax) of BMT in breast milk (time frame: 24 hours). Time to reach Cmax of BMT in breast milk (Tmax) (time frame: 24 hours).

It also tracked 5 secondary outcomes, for example Levels of Bremelanotide (BMT) in Plasma Over 24h After Administration of Vyleesi, Maximum observed concentration (Cmax) of BMT in Plasma, Time to reach Cmax of BMT in Plasma (Tmax) and Milk:plasma ratio (M/P) of BMT Levels.

What This Means in Plain Language

Put simply, this is a phase 4 trial of PT-141 (Bremelanotide) in 10 people.

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

The trial is marked completed; no results are posted to the registry yet, so nothing here describes outcomes.

More context: the PT-141 (Bremelanotide) compound page, all human trials.