Vyleesi (Bremelanotide) in Adults 65 and Older: What the Data Actually Show

What Is Bremelanotide and Why Does Age Matter?

Bremelanotide is a cyclic heptapeptide melanocortin receptor agonist delivered via a single-use subcutaneous auto-injector. The FDA approved it in June 2019 under the brand name Vyleesi for premenopausal women with acquired, generalized HSDD, the same indication held by flibanserin (Addyi). Unlike flibanserin, which requires daily oral dosing, bremelanotide is taken on demand, 45 minutes before anticipated sexual activity, no more than once per 24 hours. FDA prescribing information

Age changes almost every variable that governs drug behavior. Renal and hepatic clearance decline with age, body composition shifts toward higher fat and lower lean mass, plasma protein concentrations fall, and cardiovascular reserve narrows. For a drug whose primary safety signal is a transient but real blood-pressure elevation, those changes are not trivial.

The Mechanism Behind the BP Signal

Bremelanotide activates MC1R, MC3R, and MC4R receptors. MC4R stimulation in the hypothalamus is thought to drive the pro-sexual central effect, but peripheral MC1R and MC3R activation produces vasoconstriction, the mechanism behind the documented blood-pressure rise. Pfaus JG et al., 2010, Pharmacology Biochemistry and Behavior

In younger women with intact baroreceptor reflex and cardiovascular reserve, a 6 mmHg systolic spike resolves within 12 hours and rarely causes clinical harm. In a 70-year-old with baseline hypertension, reduced baroreceptor sensitivity, or concurrent antihypertensive therapy, that same spike may carry meaningfully higher risk.

Why the Geriatric Label Gap Exists

The RECONNECT-1 and RECONNECT-2 randomized controlled trials, the two key studies supporting FDA approval, enrolled a combined 1,267 premenopausal women. Simon JA et al., 2019, Obstetrics and Gynecology The median age in those trials was approximately 38 years. Women over 55 represented fewer than 2% of the combined sample, and the FDA prescribing label contains no pharmacokinetic or safety subgroup data specifically for adults 65 and older. That gap is not incidental. The approved indication is restricted to premenopausal women, so postmenopausal women of any age, and by extension nearly all women 65 and older, fall outside the labeled use.

Clinical Trial Evidence: What the RECONNECT Data Show

The RECONNECT program (Research of CNS Neurons Needing Excitatory Connections Trial) is the primary evidence base for bremelanotide efficacy.

RECONNECT-1 and RECONNECT-2 Efficacy Outcomes

RECONNECT-1 (N=627) and RECONNECT-2 (N=640) were 24-week, randomized, double-blind, placebo-controlled trials. Women self-administered bremelanotide 1.75 mg subcutaneously before sexual events. The co-primary endpoints were change from baseline in the Female Sexual Function Index (FSFI) desire domain score and change in the Female Sexual Distress Scale-Desire/Arousal/Orgasm (FSDS-DAO) item 13 score. Simon JA et al., 2019, Obstetrics and Gynecology

Bremelanotide produced statistically significant improvements on both co-primary endpoints in both trials. The FSFI desire domain improved by a mean of 0.35 points over placebo in RECONNECT-1 and 0.27 points in RECONNECT-2, modest in absolute magnitude but statistically significant (P<0.01 in both). The FSDS-DAO item 13 score (distress about low sexual desire) improved by 0.30 points over placebo.

What "Statistically Significant" Means in Practice

A 0.35-point FSFI subscale improvement is small. The minimum clinically important difference for the full FSFI is debated; some authors place it near 2 to 3 points on the 36-point total scale. Rosen R et al., 2000, Journal of Sex and Marital Therapy Individual responders in RECONNECT did report meaningful subjective improvement, but aggregate effect sizes were modest. For a geriatric patient, weighing a modest benefit against a more complex safety profile is especially important.

Adverse Events in the Trial Population

Nausea occurred in 40.4% of bremelanotide-treated participants vs. 10.1% with placebo, the most common adverse event by a wide margin. Flushing affected 20.3% and headache 11.3% of the bremelanotide group. FDA prescribing information The transient blood-pressure increase (mean peak systolic rise 6 mmHg, diastolic 4 mmHg, heart rate decrease of 3 bpm) resolved within 12 hours in most participants without treatment. Hyperpigmentation of the face, gums, and breasts occurred in 1% of participants with chronic use above the recommended frequency.

None of these adverse-event rates can be directly extrapolated to adults 65 and older, because that group was not studied.

Pharmacokinetics in Older Adults: The Aging Body Changes Everything

Renal Clearance and Bremelanotide Exposure

Bremelanotide is eliminated primarily by peptide hydrolysis and secondarily by renal excretion. Moderate renal impairment (eGFR 30 to 59 mL/min/1.73 m²) increases bremelanotide area under the curve (AUC) by approximately 72% relative to normal renal function. The FDA label states that bremelanotide is not recommended in severe renal impairment (eGFR <30). FDA prescribing information

The National Health and Nutrition Examination Survey found that approximately 38% of adults aged 65 and older have an eGFR below 60 mL/min/1.73 m². Coresh J et al., 2007, JAMA That means a substantial proportion of geriatric patients would already meet criteria for the "moderate impairment" category associated with a 72% AUC increase, before any dose is given.

Hepatic Metabolism Considerations

Bremelanotide undergoes extensive peptide bond hydrolysis. Hepatic impairment studies showed no clinically relevant change in exposure with mild-to-moderate hepatic impairment, and severe hepatic impairment has not been studied. FDA prescribing information The hepatic contribution to clearance appears less consequential than the renal pathway, but age-related reductions in hepatic blood flow (estimated at 0.3 to 1.5% per year after age 25) still reduce first-pass clearance for many co-administered drugs, complicating polypharmacy risk assessment. Le Couteur DG et al., 2013, Clinical Pharmacology and Therapeutics

Volume of Distribution and Body Composition

Bremelanotide is approximately 21% plasma-protein bound, relatively low, meaning protein-binding displacement by competing drugs is unlikely to be a major interaction mechanism. However, the volume of distribution at steady state is approximately 40 L. In older adults, increased adipose tissue relative to lean body mass may alter distribution of lipophilic peptide fragments, potentially extending effective exposure. No geriatric-specific volume-of-distribution data have been published.

Blood Pressure Risk in Geriatric Patients: A Closer Look

Baseline Hypertension Prevalence in Adults 65+

Hypertension affects approximately 70% of U.S. Adults aged 65 and older, based on National Health and Nutrition Examination Survey data analyzed for the American College of Cardiology/American Heart Association 2017 guideline. Whelton PK et al., 2018, Journal of the American College of Cardiology The bremelanotide prescribing label explicitly states that the drug should not be used in patients with cardiovascular disease, including uncontrolled hypertension, because of the additive risk from the drug's vasoconstrictive mechanism. The intersection of a 70% hypertension prevalence rate and a drug carrying a blood-pressure warning creates an obvious prescribing challenge in geriatric practice.

Baroreceptor Reflex Decline

Age-related baroreceptor reflex impairment is well documented. Older adults show a reduced heart-rate response to blood-pressure perturbations, meaning that the compensatory mechanisms that attenuate a transient vasopressor event in younger patients are less effective. Monahan KD, 2007, Exercise and Sport Sciences Reviews The 3-bpm heart-rate decrease seen in RECONNECT participants (reflecting baroreflex-mediated compensation) may be attenuated or absent in older patients, leaving the systolic spike unchecked.

The 12-Hour No-Drive Window

The FDA label requires patients to avoid driving or hazardous activity for 12 hours after each dose because of flushing, dizziness, and the BP perturbation. Older adults already carry higher fall and motor vehicle crash risk. A 12-hour mandatory activity restriction per sexual encounter adds a practical safety burden that should be discussed explicitly.

HSDD in Postmenopausal Women: What Else Works?

Because bremelanotide's labeled indication excludes postmenopausal women, prescribers evaluating a patient 65 or older with HSDD should consider alternatives with evidence in that population.

Estrogen and Testosterone in Older Women

Systemic estrogen therapy remains the foundation of postmenopausal sexual function treatment when genitourinary symptoms drive the complaint. The 2022 Menopause Society (formerly NAMS) Clinical Practice Statement supports low-dose vaginal estrogen for genitourinary syndrome of menopause (GSM) with a favorable safety profile at doses below systemic threshold. The Menopause Society, menopause.org

Testosterone therapy, specifically transdermal testosterone at 300 mcg/day, is supported by a Cochrane review of 36 randomized trials (N=8,480) showing benefit for postmenopausal women with HSDD, with a standardized mean difference of 0.36 (95% CI 0.22 to 0.49) for satisfying sexual events. Islam RM et al., 2019, Cochrane Database of Systematic Reviews No testosterone formulation is FDA-approved for women in the United States, but off-label use is common and supported by international guideline bodies including the Endocrine Society.

Flibanserin (Addyi) Comparison

Flibanserin, the only other FDA-approved HSDD treatment, is also labeled for premenopausal women only. Its daily oral dosing, alcohol-interaction black box warning, and CNS side-effect profile (somnolence, dizziness) may be even less favorable in older adults than bremelanotide's on-demand use pattern. Neither drug has been rigorously studied in adults 65 and older.

Polypharmacy and Drug Interaction Risk

Adults 65 and older take an average of 5 prescription medications per day. Charlesworth CJ et al., 2015, Journals of Gerontology Bremelanotide carries a documented interaction with naltrexone (the drug reduces bremelanotide bioavailability by approximately 35%) and may affect the oral bioavailability of co-administered drugs taken within 1 hour of injection, because it transiently slows gastric emptying. FDA prescribing information

Clinicians should review any oral medication taken on sexual-event days with attention to narrow therapeutic index drugs, including warfarin, digoxin, and certain antiepileptics, that may have absorption altered by delayed gastric emptying. The interaction data were collected in younger adults; geriatric patients with more complex regimens have not been specifically studied.

What the FDA Label Actually Says About Older Patients

The FDA-approved prescribing information for bremelanotide states: "Clinical studies of bremelanotide did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects." FDA prescribing information This standard geriatric disclaimer reflects genuine absence of data rather than a safety clearance.

The label also notes that bremelanotide is contraindicated in patients with known cardiovascular disease, and it should not be used in patients with uncontrolled hypertension. Given the cardiovascular co-morbidity burden in adults over 65, these contraindications will apply to a large fraction of geriatric patients being considered for the drug.

A Clinical Decision Framework for Prescribers

When a patient 65 or older presents requesting bremelanotide, a structured evaluation should address five questions before any prescription:

1. Is the indication within the label? Bremelanotide is approved only for premenopausal women. Postmenopausal use is off-label and should be documented as such, with informed consent.
2. Is cardiovascular disease or uncontrolled hypertension present? Either is a contraindication. Obtain a recent BP measurement and review the cardiac history.
3. What is the current eGFR? A value below 60 mL/min/1.73 m² signals a 72% or greater AUC increase; below 30 mL/min/1.73 m² the drug is not recommended.
4. What oral medications are taken on sexual-event days? Identify any narrow therapeutic index drugs and counsel the patient to take those medications at least 1 hour before the injection or to delay them until after gastric emptying normalizes.
5. Has the patient been offered evidence-based alternatives? Low-dose vaginal estrogen, transdermal testosterone (off-label), and psychosexual therapy all carry evidence in postmenopausal women and should be discussed.

Special Populations Within the 65+ Group

Adults 75 and Older

No subgroup data exist for adults 75 and older. The physiologic changes described above (reduced renal clearance, baroreceptor impairment, polypharmacy) are more pronounced in the "oldest old." Any consideration of bremelanotide in this group would require even more careful individual risk assessment than in the 65-to-74 range.

Patients With Cognitive Impairment

Bremelanotide crosses the blood-brain barrier, that is intrinsic to its central mechanism of action. In animal models, melanocortin system activation has shown neuroprotective signals, but no human data exist on bremelanotide effects in patients with Alzheimer disease or other dementias. Catania A et al., 2004, Pharmacological Reviews Informed consent capacity must be assessed before prescribing any sexual-enhancement therapy to patients with cognitive impairment.

Patients on Antidepressants

Selective serotonin reuptake inhibitors (SSRIs) are among the most common causes of acquired HSDD in women of all ages. Clayton AH et al., 2018, Journal of Clinical Psychiatry Older adults have high rates of SSRI use for depression, anxiety, and neuropathic pain. Bremelanotide's mechanism is distinct from serotonergic pathways, so pharmacodynamic antagonism is not expected, but the interaction has not been formally studied in geriatric populations.

Injection Technique and Practical Administration in Older Adults

Bremelanotide is supplied as a 1.75 mg/0.3 mL single-use auto-injector for subcutaneous administration into the abdomen or thigh. FDA prescribing information Older adults may face barriers including reduced grip strength, impaired fine motor control, and subcutaneous tissue changes that affect absorption. Prescribers should assess injection technique capability during the initial visit and consider whether a caregiver or partner may need instruction.

The auto-injector does not require refrigeration. Storage at room temperature (below 30°C) is acceptable, which reduces the management burden for patients who travel.

Monitoring Recommendations for Older Patients

Given the pharmacokinetic and cardiovascular concerns detailed above, the following monitoring parameters are reasonable for any older adult prescribed bremelanotide off-label:

Blood pressure should be measured at baseline and again approximately 2 weeks after the first use. Patients should be instructed to record their BP at home for the 12 hours following their first two to three injections, using a calibrated home monitor. If systolic BP rises above 140 mmHg or diastolic above 90 mmHg during this window, the prescriber should be notified.

Renal function (serum creatinine and calculated eGFR) should be checked at baseline. Any eGFR below 30 mL/min/1.73 m² is a reason to withhold the drug. An eGFR between 30 and 59 mL/min/1.73 m² warrants explicit discussion of the 72% increase in drug exposure and potential dose-effect on blood pressure.

A medication reconciliation review should occur at the time of prescribing, with specific attention to the gastric-emptying interaction window and narrow therapeutic index oral drugs. FDA prescribing information

Regulatory and Guideline Context

The International Society for the Study of Women's Sexual Health (ISSWSH) published a process-of-care algorithm for HSDD in 2019, predating any geriatric-specific guidance on bremelanotide. The algorithm recommends bremelanotide as a second-line option after shared decision-making, psychoeducation, and addressing contributing medical factors. Goldstein I et al., 2019, Mayo Clinic Proceedings The ISSWSH guidance does not include age-specific recommendations or geriatric dosing modifications because the data do not yet exist to support them.

The Endocrine Society's 2019 clinical practice guideline on female sexual dysfunction emphasizes that evaluation should include assessment of relationship factors, mental health, and medication effects before any pharmacologic treatment is initiated. Parish SJ et al., 2019, Journal of Clinical Endocrinology and Metabolism That recommendation applies with extra weight in older patients, where co-morbidities, relationship context, and medication burden are all more complex.

As of the article's last review date, the FDA has not issued any label update extending bremelanotide's indication to postmenopausal women or providing geriatric-specific dosing guidance. Clinicians should check the current prescribing information at accessdata.fda.gov for the most recent labeling.