Bremelanotide

Bremelanotide, also known as PT-141, is a powerful peptide (a compound consisting of two or more amino acids) that activates internal pathways in the brain involved in normal sexual responses. This FDA-approved drug is also a melanocortin receptor agonist, which helps activate a type of protein known as melanocortin receptor. It is given by subcutaneous injection (under the skin) using a single use autoinjector pen. Scientific studies report that administration of this peptide has shown promise in various aspects of health.

Overall Health Benefits of Bremelanotide

• Improves Sexual Health [1-15]
• Reverses Steroid-Induced Weight Gain [16]
• Improves Mood [17]
• Improves Blood Sugar Levels [18-20]
• Improves Lipid Profile [21]
• Increases Energy Levels [22-24]
• Improves Eye Health [25-27]
• Promotes Weight Loss [28-30]
• Fights Alcohol Addiction [31-33]
• Boosts Immune Function [34-39]
• Improves Cognitive Health [40-48]

Sexual Health

Sexual dysfunction often affects one’s self-confidence and relationship with partner. Fortunately, this condition is very treatable with bremelanotide. In fact, the FDA approved bremelanotide in June 2019 as a therapeutic option for women with low libido after it showed an increase in sexual desire and reduction in distress in two replicate phase 3 trials involving women with hypoactive sexual desire disorder (HSDD). [1-2] It now joins flibanserin, the only other drug approved by the FDA for the treatment of HSDD in premenopausal women.

Numerous human studies have also shown promising results with regards to the therapeutic benefits of bremelanotide on sexual health:

• In premenopausal women with sexual dysfunctions, bremelanotide self-administration at various does (0.75, 1.25 or 1.75 mg) as desired over 12 weeks, resulted in significant improvements in female sexual function index total score and female sexual distress scale-desire/arousal/orgasm total score compared to placebo. [3]
• In female subjects with arousal disorder, administration of 20-mg bremelanotide given as an intranasal spray on “as required” basis 45–60 minutes before attempting sexual intercourse, was associated with significantly greater intercourse satisfaction compared to placebo. [4]
• In premenopausal women with sexual arousal disorder, administration of a single intranasal dose of 20 mg bremelanotide was associated with moderate or high sexual desire and improved satisfaction with their level of sexual arousal compared to placebo treatment. [5]
• In clinical trials, administration of bremelanotide in healthy women showed increased vaginal blood flow as well as increased sexual desire and arousal. [6-8]
• Administration of bremelanotide to normal men and to patients with erectile dysfunction (ED) resulted in a rapid dose-dependent increase in erectile activity. [9]
• In healthy male subjects and in patients with an inadequate response to Viagra, bremelanotide administration at doses greater than 1 mg resulted in a statistically significant erectile response. [10-11]
• In a first Phase IIB at home study, administration of bremelanotide resulted in significant improvements in erectile function as assessed by the International Index of Erectile Function (IIEF). [12]
• Co-administration of sildenafil and 7.5 mg intranasal bremelanotide has been shown to induce significantly prolonged time of penile erections compared with sildenafil alone. [13]
• In a 12-week phase IIb trial recruiting 726 non-diabetic men suffering from ED, bremelanotide administration at a dose of 5 mg was associated with significantly higher scores in the International Index of Erectile Function (IIEF-5) Questionnaire. [14]
• A study found that bremelanotide’s effect on penile erection can be compared to standard drugs for ED. [15]

Steroid Induced Weight Gain

Steroids are often extremely effective in alleviating pain and inflammation. However, this drug can affect fat metabolism, which ultimately leads to weight gain. Studies show that bremelanotide counteracts steroid induced weight gain in patients who are on chronic steroid therapy. [16]

Mood

In men and women with sexual dysfunction, low mood and depression are very common. Because of the therapeutic benefit of bremelanotide on libido and sexual performance, this powerful peptide has been studied for its mood-enhancing effect. Studies show that bremelanotide exerts its antidepressant and anti-anxiety effects by improving the function of the central nervous system, resulting in improved overall mood. [17]

Blood Sugar

Studies show that melanocortin receptor agonists help protect against diabetes and the negative effects of high blood sugar through the following mechanisms:

• By improving the body’s response to the effects of insulin (insulin sensitivity). [18-19]
• In murine models of obesity and type 2 diabetes, melanocortin receptor agonists significantly improve blood sugar tolerance and reduce blood levels of insulin. [20]

Abnormal Lipid Profile

There is also evidence that melanocortin receptor agonists such as bremelanotide may help correct abnormal lipid levels. In streptozotocin-induced diabetic mice, injection of melanocortin receptor agonist reduces fat formation in the liver, thereby improving abnormal lipid metabolism associated with insulin-deficiency. [21]

Energy Levels

Melanocortin receptor agonists such as bremelanotide may help increase energy levels as well as productivity. Studies show that melanocortin receptor agonists play a critical role in the regulation of food intake and energy expenditure, primarily through regulation of the activity of the sympathetic nervous system. [22-24]

Eye Health

Photoreceptor cell, a specialized type of neuron found in the retina, is particularly vulnerable to high blood sugar levels. Studies show that melanocortin receptor agonists helps preserve eye health by:

• In mice, it counteracts the harmful effects of high blood sugar levels on the eyes. [25]
• In murine models, it protects retinal vascular network by inhibiting local inflammatory and immune responses. [26-27]

Weight Loss

Studies show that the melanocortin receptor agonist bremelanotide may also help improve body composition by inducing weight loss:

• In obese nonhuman primate model, treatment with melanocortin receptor agonist decreased food intake by 35%, with persistent weight loss over 8 weeks of treatment (13.5%). [28]
• In rodent models, melanocortin receptor agonists have been shown by several investigators to decrease food intake and body weight. [29-30]

Alcohol Addiction

Recent data have implicated that melanocortin receptor agonists such as bremelanotide may play a role in modulating voluntary ethanol (alcohol) consumption, thereby treating alcohol addiction. In mice, melanocortin receptor agonist administration effectively reduces ethanol drinking, suggesting that it can be a potential therapeutic option for alcohol abuse disorders. [31-33]

Immune Function

Melanocortin receptor agonists such as bremelanotide play a crucial role in strengthening the immune system. Studies show that melanocortin receptor agonists exert its immune boosting effects through the following important mechanisms:

• It enhances the activities of the cells of the immune system, including neutrophils, monocytes, dendritic cells, B-lymphocytes, and white blood cells. [34-36]
• It has potent anti-inflammatory effect. [37-39]

Cognitive Health

There is increasing evidence that bremelanotide along with other melanocortin receptor agonists may help improve cognitive health. Studies show that they exert this effect through the following mechanisms:

• Melanocortin receptor agonists interact with brain chemicals that regulate socioemotional behaviors and cognitive skills, including oxytocin, dopamine, serotonin, and corticotropin-releasing factor. [40-43]
• In rodents, melanocortin receptor agonists improve general cognitive processes, including social information processing and social reinforcement. [44-48]

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