Vyleesi Geriatric (65+) Safety: What Older Women Need to Know About Bremelanotide

What Is Bremelanotide and Why Does Age Matter?

Bremelanotide (brand name Vyleesi) is a melanocortin receptor agonist approved by the FDA in June 2019 for hypoactive sexual desire disorder (HSDD) in premenopausal women. It works by activating MC1R, MC3R, and MC4R receptors in the central nervous system to modulate sexual desire pathways, rather than acting on sex-hormone levels directly. The approved dose is 1.75 mg delivered by subcutaneous autoinjector 45 minutes before anticipated sexual activity. FDA prescribing information

Age is a critical variable for three reasons. First, the key RECONNECT trials enrolled predominantly premenopausal women, meaning women 65 and older were not studied in adequate numbers to establish safety signals specific to that group. Second, normal aging changes the way the body handles drugs, blood pressure, and falls risk, each of which intersects directly with bremelanotide's known pharmacodynamic effects. Third, older women carry a higher medication burden on average, and bremelanotide slows gastric emptying, creating a pharmacokinetic interaction with every oral medication taken around the same time.

The Approved Indication Does Not Include Women 65+

The FDA label explicitly states that HSDD indication is for premenopausal women. Use of bremelanotide in postmenopausal women or in women 65 and older is off-label. Clinicians who consider prescribing it in this population must weigh that the benefit-risk profile established in RECONNECT may not translate directly, and that no large randomized controlled trial has evaluated efficacy or safety in women over 65 as a primary endpoint.

How Bremelanotide Works in the Brain

Bremelanotide does not change estrogen, testosterone, or progesterone levels. Its melanocortin agonist activity in the hypothalamus modulates dopaminergic and serotonergic circuits involved in sexual motivation. This central mechanism is pharmacologically distinct from hormone therapy and from phosphodiesterase inhibitors used in male sexual dysfunction. Because it acts centrally rather than peripherally on vascular smooth muscle, the blood pressure effect is a secondary consequence of melanocortin receptor activation rather than a direct vascular target.

RECONNECT Trial Evidence and Its Geriatric Limitations

The RECONNECT program comprised two identically designed phase 3 randomized controlled trials (RECONNECT-A and RECONNECT-B) published in Obstetrics and Gynecology in 2019. Combined, they enrolled 1,247 premenopausal women with generalized acquired or lifelong HSDD. RECONNECT, Obstet Gynecol 2019

Primary Efficacy Findings

Across the pooled RECONNECT population, bremelanotide produced a statistically significant improvement on the Female Sexual Distress Scale-Desire/Arousal/Orgasm (FSDS-DAO) total score and on the desire domain of the Female Sexual Function Index (FSFI-D). The proportion of women achieving a meaningful responder threshold on both instruments was higher in the bremelanotide arm than placebo (P<0.01 for both co-primary endpoints). These effect sizes were real but modest: the number needed to treat for one additional responder was approximately 7 to 8 across the two trials.

Why Geriatric Women Were Underrepresented

RECONNECT required participants to be premenopausal, which structurally excluded virtually all women 65 and older. The mean age of trial participants was approximately 36 years. The FDA's own prescribing information 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." This absence of data is not a minor gap; it means every geriatric safety inference must be extrapolated from pharmacokinetic modeling, adverse-event biology, and clinical judgment rather than direct trial evidence.

What the FDA Label Says About Older Patients

The label advises caution, noting that elderly patients are generally more likely to have decreased hepatic, renal, or cardiac function and to be taking concomitant medications. It does not provide a geriatric-specific dose adjustment because data to support one do not exist. Prescribers are advised to start with the standard 1.75 mg dose but to monitor more closely for cardiovascular and gastrointestinal adverse events.

Cardiovascular Safety in Women 65 and Older

This is the most clinically significant geriatric concern with bremelanotide. The drug reliably decreases blood pressure transiently after each injection, and older women have age-related vasomotor instability that can amplify this effect.

Magnitude and Duration of Blood Pressure Effect

In clinical pharmacology studies cited in the FDA label, bremelanotide decreased mean maximum systolic blood pressure by approximately 6 mmHg and mean maximum diastolic blood pressure by approximately 3 mmHg. These changes peak within 1 to 2 hours of injection and resolve within 12 hours. In younger, otherwise healthy women, this transient dip is usually not clinically meaningful. In a 70-year-old woman with baseline systolic pressure of 130 to 135 mmHg taking an antihypertensive agent, the same dip may drop perfusion pressure low enough to cause dizziness, syncope, or a fall. FDA label pharmacodynamics

Absolute Contraindication in Cardiovascular Disease

The prescribing information lists known cardiovascular disease as a contraindication. This includes established coronary artery disease, history of stroke, uncontrolled hypertension (blood pressure consistently above 165/95 mmHg), and high cardiovascular risk as defined by the clinician. Given that cardiovascular disease prevalence rises sharply after age 60, this contraindication will apply to a substantial fraction of women 65 and older presenting for HSDD treatment. The American Heart Association's 2023 statistics report estimated that approximately 44% of women aged 60 to 79 have some form of cardiovascular disease. AHA 2023 Heart Disease Statistics

Interaction With Antihypertensive Medications

Women 65 and older taking ACE inhibitors, angiotensin receptor blockers, calcium channel blockers, or diuretics will experience additive blood pressure lowering when bremelanotide is injected. Clinicians should counsel patients to avoid using bremelanotide within 2 hours of antihypertensive dosing when possible and to remain seated or supine for at least 1 hour after injection. Blood pressure should be checked at baseline and at a follow-up visit scheduled approximately 4 weeks after first use.

Renal Function and Pharmacokinetics in Older Women

Renal clearance declines by roughly 1% per year after age 40, meaning an average woman at age 65 has approximately 25% less renal clearance than she did at 40, even in the absence of diagnosed kidney disease.

How Bremelanotide Is Cleared

Bremelanotide is primarily metabolized by enzymatic hydrolysis and then excreted renally. The FDA label notes that in subjects with severe renal impairment (eGFR <30 mL/min/1.73 m²), plasma exposure (AUC) increased by approximately 1.7-fold compared to subjects with normal renal function. The label therefore advises avoiding bremelanotide in severe renal impairment and in end-stage renal disease (ESRD). No dose adjustment is specified for mild (eGFR 60 to 89) or moderate (eGFR 30 to 59) impairment, but the label's caution about general elderly use implicitly recommends closer monitoring in those subgroups. FDA label pharmacokinetics

Practical eGFR Thresholds for Prescribing Decisions

Clinicians should obtain a current eGFR before initiating bremelanotide in any patient 65 or older, not just those with known chronic kidney disease. CKD is significantly underdiagnosed in older women. The National Institute of Diabetes and Digestive and Kidney Diseases estimates that roughly 38% of adults with CKD stage 3 (eGFR 30 to 59) are unaware of their diagnosis. NIDDK CKD statistics

If eGFR is above 60, bremelanotide can be considered with standard monitoring. If eGFR is 30 to 59, heightened vigilance for adverse effects is warranted. If eGFR is below 30, the drug should not be initiated.

Hepatic Function Considerations

Severe hepatic impairment (Child-Pugh C) is a contraindication because hepatic hydrolysis of bremelanotide is reduced, raising plasma exposure. Mild to moderate hepatic impairment (Child-Pugh A or B) does not require dose adjustment but should be documented and factored into the overall risk assessment. Liver function tests are reasonable to check at baseline in women with known alcohol use, nonalcoholic fatty liver disease, or prior hepatic diagnoses.

Falls and Fracture Risk

Falls cause significant morbidity in women over 65. A transient blood-pressure drop combined with nausea-related orthostatic instability represents a real falls risk with each bremelanotide injection.

Nausea as a Contributing Factor

The most common adverse effect of bremelanotide in RECONNECT was nausea, reported by approximately 40% of women in the active treatment group. The FDA label recommends that patients take an antiemetic such as ondansetron before injection to reduce this risk. In older women, nausea that prompts sudden standing from bed or the couch also creates an orthostatic moment when blood pressure may be lowest.

Injection Timing and Setting Recommendations

Injecting bremelanotide while already reclined or seated, with another person present, reduces fall exposure. Patients should be explicitly counseled not to inject while standing in a bathroom or before walking to another room. The 45-minute window before activity gives time for the blood-pressure nadir to pass before the patient needs to be ambulatory, but this window narrows if the patient has taken an antihypertensive within the prior few hours.

Bone Health Context

Women 65 and older have substantially higher rates of osteoporosis and osteopenia than premenopausal women. A single syncopal fall in a woman with osteoporosis can result in a hip fracture with a 1-year mortality rate of approximately 20 to 30%. This is not a trivial backdrop against which to accept even a small increase in dizziness or orthostatic episodes. The USPSTF recommends bone density screening for all women 65 and older, and this baseline osteoporosis status should inform the risk-benefit discussion about any medication that may increase fall frequency. USPSTF Osteoporosis Screening 2018

Drug-Drug Interactions in Polypharmacy Patients

Women 65 and older take more medications on average than younger women. The CDC estimates that approximately 36% of adults aged 62 to 85 take five or more prescription medications simultaneously. Bremelanotide slows gastric emptying, which can meaningfully delay absorption of any oral drug taken around the same time.

Mechanism of the Interaction

Melanocortin receptor activation in the gastrointestinal tract reduces intestinal motility. For drugs with narrow therapeutic windows and time-sensitive absorption, this is not a theoretical concern. Levothyroxine, warfarin, certain anticonvulsants, and oral contraceptives (relevant if the patient is using them for non-contraceptive indications) all have absorption patterns that may be affected by delayed gastric transit. FDA label drug interactions

Time-Separation Strategy

The FDA label advises that women avoid taking other oral medications within 1 hour before or 1 hour after bremelanotide injection to mitigate this effect. In practice, an older woman taking levothyroxine in the morning and a statin at night may inject bremelanotide in the evening without any concern about levothyroxine absorption, provided timing is managed. A comprehensive medication review before initiating bremelanotide is not optional in this age group.

The HealthRX Geriatric Bremelanotide Pre-Prescribing Checklist (developed by the HealthRX medical team for use before initiating bremelanotide in any patient 65 or older):

1. Obtain current eGFR. Proceed only if eGFR is 30 mL/min/1.73 m² or above.
2. Review current antihypertensive regimen. Counsel on additive BP-lowering and advise 2-hour separation from antihypertensives where feasible.
3. Confirm absence of known cardiovascular disease or uncontrolled hypertension. If either is present, do not prescribe.
4. Assess fall risk using the STEADI toolkit or equivalent. If high fall risk, discuss risk explicitly and document shared decision-making.
5. Review bone density (DXA) status. If untested and patient is 65+, order before initiating bremelanotide.
6. Document all current oral medications and counsel on the 1-hour oral-drug separation rule.
7. Prescribe ondansetron 4 mg orally 30 minutes before the first several injections to reduce nausea-mediated orthostatic risk.
8. Schedule a 4-week follow-up blood pressure check and symptom review.
9. Set an 8-week efficacy reassessment. Discontinue if no meaningful improvement in FSFI desire domain or FSDS-DAO score.

Hepatic Considerations and Body Composition Changes With Age

Age-related changes in body composition, including decreased lean mass and increased fat percentage, can alter the volume of distribution for lipophilic drugs. Bremelanotide is a cyclic heptapeptide with moderate lipophilicity. While the FDA label does not call out a specific body-composition-related pharmacokinetic concern, the general principle that adipose tissue changes Vd in older adults is worth considering when interpreting subjective drug response.

Liver mass and hepatic blood flow both decrease with age by roughly 20 to 40% between ages 25 and 75. Hepatic clearance of bremelanotide (via enzymatic hydrolysis) may therefore be modestly slower in older women even in the absence of overt liver disease. This is another reason the FDA's general caution about elderly use is pharmacologically grounded.

Efficacy Considerations: Does the Drug Even Work Off-Label in This Population?

The RECONNECT data demonstrate efficacy in premenopausal women with HSDD. Extrapolating that effect to postmenopausal or older women is biologically plausible given that the mechanism is central rather than hormonal, but it is not proven. A secondary analysis of RECONNECT data by Clayton et al. (2019) noted that patients with the lowest baseline desire scores had the most numerically pronounced absolute improvements, a pattern that could in theory apply to postmenopausal women with severe HSDD, but no subgroup trial in women 65+ exists to confirm this. Clayton et al. 2019, Obstet Gynecol

Clinicians should discuss this uncertainty honestly. A treatment that carries real cardiovascular, falls, and drug-interaction risks in older women should only be initiated when the patient understands that the efficacy evidence does not directly apply to her demographic and that a meaningful proportion of treated women in RECONNECT did not achieve the responder threshold.

Deprescribing and Reassessment Protocols

Bremelanotide is not a chronic daily medication; it is used as needed. This as-needed structure does reduce some cumulative-exposure concerns, but it also makes it easy for patients to continue indefinitely without evaluating whether the drug is actually helping.

Defining a Meaningful Response

A clinically meaningful response is typically defined as an improvement of at least 1.2 points on the FSFI desire domain (range 0 to 6) or a reduction of at least 1.2 points on the FSDS-DAO. If a patient reports no change in subjective desire or no reduction in distress after 8 weeks of at-least-monthly use, the drug should be stopped.

When to Reassess Versus Discontinue

At 8 weeks, the treating clinician should review: (1) whether the patient has noticed any benefit in desire or distress, (2) whether adverse events such as nausea, flushing, or dizziness have occurred and at what frequency, and (3) whether any new medications have been added that create interaction concerns. If two of those three indicators are unfavorable, discontinuation is the appropriate recommendation. Bremelanotide has no withdrawal syndrome; it can be stopped without tapering.

Shared Decision-Making: The Conversation to Have

The American College of Obstetricians and Gynecologists (ACOG) published guidance in 2019 noting that HSDD is underdiagnosed in older women and that treatment should always be considered in the context of the patient's overall health, relationships, and goals. ACOG's committee opinion states: "Treatment decisions for sexual dysfunction should be individualized, taking into account the woman's preferences, medical history, and the potential risks and benefits of available therapies." ACOG Committee Opinion 2019

For a 65-year-old woman with well-controlled hypertension, eGFR of 55, no history of syncope, and mild osteopenia, a thoughtful conversation about bremelanotide's modest benefits and real risks may conclude that a trial is reasonable with close monitoring. For a 70-year-old woman with moderate CKD (eGFR 32), prior stroke, and five antihypertensive or cardiac medications, the risk-benefit calculation points clearly against prescribing. The gap between those two patients is wide enough that a blanket policy in either direction does the individual patient a disservice.