PT-141 and women's health

What sources report

Who the approval covers

The label defines HSDD as low sexual desire that causes marked distress or interpersonal difficulty.¹ The low desire must not be due to another medical or psychiatric condition, problems in the relationship, or a medicine or drug.⁷ Acquired HSDD develops in a woman who previously had no problems with desire.¹ Generalized HSDD occurs regardless of the type of stimulation, situation or partner.¹ The approval covers premenopausal women with this acquired, generalized form.¹

Who was studied

The two RECONNECT trials randomized 1,267 premenopausal women 1:1 to bremelanotide or placebo for 24 weeks.² Of those, 1,247 were in the safety analysis and 1,202 in the efficacy analysis.² Their mean age was 39, with a range of 19 to 56, and 86% were white and 12% Black.¹ On average they had been in monogamous relationships for about 12 years and had had HSDD for about 4 years.¹ Women injected 1.75 mg by autoinjector as needed.¹ Most used it two to three times a month and no more than once a week.¹

What women experienced

On average, desire scores rose and distress about low desire fell more than with placebo, but the number of satisfying sexual events did not differ significantly from placebo.²¹ About 58% of women on bremelanotide rated themselves as benefiting on a global question, versus about 36% on placebo.² Put another way, roughly 22 more women in every 100 reported benefit than on placebo, while many women on placebo also reported benefit.² In a 52-week open-label extension, 684 women continued, and the authors reported sustained improvement; 272 completed it.¹⁰ The effect sizes and the independent re-analyses are covered in PT-141 benefits and uses.

The most common side effects were nausea (40%), flushing (20.3%), injection site reactions (13.2%) and headache (11.3%).¹ Nausea began a median of 30 minutes after a dose and lasted a median of 2.4 hours.² Each dose raised blood pressure by up to 6 mmHg systolic, usually back to baseline within 12 hours.¹ The full list is in PT-141 side effects.

Other studies that enrolled women

• Dose-finding trial (2016): 12 weeks in premenopausal women with female sexual dysfunction, comparing three doses with placebo; 327 women were in the efficacy analysis.¹¹
• Blood pressure monitoring trial (2017): in 397 premenopausal women, the 1.75 mg dose raised systolic pressure about 3 mmHg more than placebo in the 4 hours after a dose, and peak rises usually lasted under 15 minutes.¹²
• Daily dosing study: in 127 premenopausal women given Vyleesi once daily for 8 days, average daytime systolic pressure rose 1.9 mmHg and diastolic 1.7 mmHg.¹
• Nausea prevention study: in 228 healthy women, ondansetron taken 30 minutes before a dose did not reduce nausea.¹
• Alcohol study: 12 of the 24 healthy adults were women; a 20 mg nasal dose taken with alcohol caused no significant drug-related drops in blood pressure.¹³

What the label asks prescribers to check

Before and during treatment, the label asks prescribers to weigh cardiovascular risk and make sure blood pressure is well controlled.¹ It contraindicates the drug in uncontrolled high blood pressure or known cardiovascular disease.¹ It tells prescribers to advise effective contraception during use and stopping if pregnancy is suspected.¹ It also covers oral medicines: slowed stomach emptying can reduce their absorption, so the label advises avoiding Vyleesi with oral drugs that need a threshold level to work, such as antibiotics.¹ Finally, it sets an 8-week point at which treatment stops if a woman reports no improvement.¹

Groups the evidence does not cover well

• After menopause: effectiveness has not been established, and the label does not cover postmenopausal women.²¹
• Women of color: the trial population was mostly white, which the authors list as a limitation.² People with dark skin were also more likely to develop patches of darker skin.¹
• Women with heart risk: bremelanotide must not be used with uncontrolled high blood pressure or known cardiovascular disease, and it is not recommended at high cardiovascular risk.¹
• Pregnancy: the trials recorded 7 pregnancies among more than 1,057 women treated for up to 12 months, with no major birth defects reported.¹ Two required pregnancy outcome studies, a registry and an insurance claims study, are scheduled for completion in May 2030.⁷
• Women taking oral medicines: bremelanotide may slow stomach emptying and reduce absorption of drugs taken by mouth.¹ The label says to avoid it with oral naltrexone products.¹
• Daily use: in a label study of 8 days of daily dosing, 38% developed patches of darker skin.¹ The label advises against more than 8 doses a month.¹

What female animal studies add

In female rats, PT-141 selectively increased solicitation behavior without affecting lordosis, pacing or other sexual behaviors.¹⁴ A 2022 review links its effect on desire to MC4 receptors in the hypothalamus and dopamine release, a model based mainly on animal studies.¹⁵ The label itself says the mechanism in women with HSDD is unknown.¹

Another approved option for HSDD

Flibanserin (Addyi) is also FDA approved for acquired, generalized HSDD in women.⁶ It is a 100 mg tablet taken every night at bedtime.⁶ Since a December 2025 label change, it covers women under 65, including postmenopausal women.⁶ It acts on serotonin receptors, and its label carries a boxed warning about low blood pressure and fainting, including with alcohol taken close in time.¹⁶⁶ A full comparison is on What is Vyleesi?.

What the label says

The Vyleesi label approves 1.75 mg under the skin of the abdomen or thigh, as needed, at least 45 minutes before anticipated sexual activity.¹ It allows no more than one dose in 24 hours, does not recommend more than 8 doses a month and says to stop after 8 weeks without improvement.¹ The prescriber sets the dose and decides whether the drug suits a patient. The label excludes postmenopausal women, men and use to enhance sexual performance.¹ It advises women who can become pregnant to use effective contraception while taking it.¹ Its approval letter required a breastfeeding trial and two pregnancy outcome studies after approval.⁷

For dosing details, see PT-141 dosage, and for the compound itself, What is PT-141?. Other compounds studied for women's health are on Peptides and women's health.