LIB-01 (Volufralin)

Early human Sexual Wellness 3 sources

LIB-01 (Volufralin) is a novel, first-in-class oral drug candidate being developed for the treatment of erectile dysfunction (ED) and premature ejaculation. It works by enhancing melanocortin type-4 receptor (MC4R) signaling in the central nervous system, demonstrating a unique long-lasting effect that can improve erectile function for up to eight weeks after a short dosing period.

01Dosing reference

Amount

10-50 mg (in clinical trials)

Frequency

Once daily for 3 days (investigational regimen)

Cycle

Monthly dosing interval (proposed based on sustained 8-week efficacy)

Reference figures, not a recommendationThese values reflect amounts described in the literature and vendor documentation this database indexes. Use the reconstitution calculator to convert them into syringe units.

02Mechanism of action

MC4R Upregulation

LIB-01 increases the gene expression of both the melanocortin type-4 receptor (MC4R) and its natural agonist in the brain and spinal cord.

Enhanced Neural Signaling

The increased MC4R signaling modulates nerve signals that control sexual function, leading to improved arterial blood flow to the penis and relaxation of erectile tissue.

Sustained Pro-Erectile Effect

Because it alters gene expression rather than just temporarily binding to existing receptors, LIB-01 produces a long-lasting improvement in erectile function that persists even after the drug has left the body.

03Human evidence

In a Phase 2a study, a single 3-day oral treatment of LIB-01 (25 mg and 50 mg) produced clinically meaningful improvements in erectile function at 4 weeks, with effects sustained through 8 weeks.

Double-blind, placebo-controlled trial involving 156 men (ages 26-65) with mild to moderate ED. 31% of patients with moderate ED in the 50 mg group became complete responders.

Phase 1 first-in-human trials demonstrated that LIB-01 was safe and well-tolerated when orally administered at single and multiple ascending doses.

Conducted in healthy male volunteers to establish the primary safety profile and pharmacokinetics before advancing to efficacy trials.

04Preclinical evidence

LIB-01 demonstrated a positive effect on erectile function by upregulating the body's own production of MC4R and its natural activator.

Gene expression analysis in anatomical structures (nerve and vascular tissues) in animal models.

Preclinical studies indicated potential impacts on factors related to metabolic diseases, such as obesity and diabetes, due to MC4R's role in energy metabolism.

Ongoing preclinical evaluations exploring secondary indications beyond sexual dysfunction.

05What is known vs. unknown

Reasonably established

LIB-01 is an oral medication that targets the central nervous system rather than acting locally like PDE5 inhibitors (e.g., Viagra).
It has a unique long-lasting duration of action, showing sustained efficacy for up to 8 weeks after just a 3-day dosing regimen.
Clinical trials indicate it is well-tolerated, with the most common side effect being mild, transient gastrointestinal upset.
It may offer a solution for men who do not respond to current first-line ED treatments.

Unknowns & limits

Long-term safety and efficacy beyond the 8-week period evaluated in Phase 2a trials are not yet fully established.
It is still in clinical development (planning Phase 2b in 2026) and is not yet FDA-approved or available for public use.
The exact extent of its potential benefits for metabolic conditions like obesity remains under preclinical investigation.

06Safety & regulatory context

Regulatory statusLIB-01 is currently an investigational drug in Phase 2 clinical trials and is not approved by the FDA or other regulatory bodies for medical use. In clinical studies to date, it has demonstrated a favorable safety profile and was well-tolerated at all tested dose levels (up to 50 mg). Adverse events have been few, primarily mild and transient, occurring during the initial days of administration. The most commonly reported side effect is mild, self-limiting gastrointestinal upset. Because it acts on the central nervous system via the melanocortin system, ongoing trials will continue to monitor for any central or systemic side effects.

07Compared with PT-141 (Bremelanotide)

LIB-01 (Volufralin) vs. PT-141 (Bremelanotide)

Key difference

While both target the MC4 receptor, PT-141 is a synthetic peptide agonist that binds to existing receptors and requires on-demand dosing (usually via injection). LIB-01 is an oral drug that increases the gene expression of MC4R and its natural agonist, resulting in a sustained effect lasting weeks after a short dosing period.

When researchers discuss each

PT-141 is discussed as an on-demand, FDA-approved (for HSDD in women) injectable option for sexual dysfunction, whereas LIB-01 is discussed as a next-generation, long-acting oral candidate that may eliminate the need for daily or on-demand dosing.

08Glossary

Melanocortin Type-4 Receptor (MC4R)

A receptor in the brain and spinal cord involved in regulating sexual function, hunger, and energy metabolism.

Gene Expression

The process by which information from a gene is used to create functional products like proteins or receptors in the body.

Agonist

A substance that binds to a receptor and activates it to produce a biological response.

09Knowledge check

Q1How does LIB-01's mechanism of action differ from traditional synthetic peptide MC4R agonists like PT-141?

Q2Based on Phase 2a clinical trial results, how long did the pro-erectile effects of a 3-day oral treatment of LIB-01 last?

Q3Which of the following limitations of the current evidence for LIB-01 is explicitly noted in the dossier?

Q4According to the dossier's stated comparison, which practical difference best distinguishes LIB-01 from PT-141 (Bremelanotide)?

Q5Which statement best reflects LIB-01's regulatory and safety context as described in the dossier?

10Sources

More in Sexual Wellness

See all

PT-141 (Bremelanotide)

Sexual Wellness

FDA-approved context

PT-141, also known as bremelanotide, is a synthetic peptide analog of alpha-melanocyte-stimulating hormone (α-MSH). It acts as a non-selective agonist of the melanocortin receptors, primarily MC4R, and is FDA-approved for the treatment of generalized hypoactive sexual desire disorder (HSDD) in premenopausal women. Research shows it can also induce erections in men, working through the central nervous system rather than the vascular system.

1.75 mg (FDA approved dose) or 1-2 mg for research

Alprostadil (Prostaglandin E1)

Sexual Wellness

FDA-approved context

Alprostadil is a synthetic form of prostaglandin E1 (PGE1), a naturally occurring vasodilator. It is widely researched and utilized for its ability to relax smooth muscle and expand blood vessels, making it a primary treatment for erectile dysfunction and a critical intervention for maintaining ductus arteriosus patency in neonates with specific heart conditions.

1.25 to 20 mcg (ED injection); 125 to 1000 mcg (urethral suppository)

Research and educational use onlyNothing on this site is medical advice, a prescription, or a recommendation for human use. Compounds documented here are research chemicals. Consult a qualified clinician before making any health decision.