Melanotan 2 (otherwise known as MT2) was first synthesized at the University of Arizona. Researches there knew that onc of the best defenses against skin cancer was melanin activated in the skin, a tan. They hypothesized that an effective way to reduce skin cancer rates in people would be to induce the body's natural pigmentary system to produce a protective tan prior to UV exposure. The body's naturally occuring hormone MSH causes melanogenesis, a process by which the skin's pigment cells (melanocytes) produce the skin's pigment (melanin). They tested to see if administering this endogenous hormone to the body directly could be an effective method to cause sunless tanning. What they found was that while it appeared to work, natural MSH had too short a half life in the body to be practical as a therapeutic drug. So they decided to find a more potent and stable alternative, one that would be more practical.
After synthesizing and screening hundreds of molecules, the researchers headed by Victor J. Hruby and Mac E. Hadley, found a peptide, [Nle4, D-Phe7] MSH, that was approimately 1,000 times more potent than the natural MSH. They dubbed this new peptide molecule, "Melanotan" (later Melanotan-1, now know as afamelanotide). They subsequently developed another analog, Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2), which they called "Melanotan II". The scientists hoped to use these peptides to combat melanoma by stimulating the body's natural pigmentary mechanism to create a tan without first needing exposure to harmful levels of UV radiation. This in turn, they hypothesized, could reduce the potential for skin damage that can eventually lead to skin cancer.
A pilot phase I clinical trial conducted on three males by the College of Medacine, Pharmacology Department, University of Arizona in Tuscon, Arizona pulished in 1996 reported that, "Melanotan II has tanning activity in humans given only 5 low doses every other day by subcutaneous injection." The side effects reported were mild nausea and a "stretching and yawning complex" that correlated with spontaneous penile erections.
The Department of Pharmacology, University of Arizona College of Medacin published in 1998 that involved 10 men who suffered from psychogenic erectile dysfunction. Their trial concluded that, "Melanotan II is a potent initiator of erections in men with pyschogenic erectile dydfunction and has manageable side effects at a dose of 0.025mg/kg.
A clinical study published in 2000 of 20 men with psychogenic and organic erectile dysfunction conducted at the Section of Urology of The University of Arizona College of Medacin concluded, "that Melanotan II is a potent initiator of penile erection in men with ecrectile dysfunction.
