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:''Note: this article describes afamelanotide which is also known by the name melanotan I. afamelanotide should not be confused with melanotan II.'' Afamelanotide ( (INN) (brand name Scenesse), also known as melanotan I (or melanotan-1), originally developed at the University of Arizona and now by Clinuvel Pharmaceuticals, is a synthetic peptide and analogue of the naturally occurring melanocortin peptide hormone α-melanocyte stimulating hormone (α-MSH) that has been shown to induce the production of darkening dermal pigmentation through melanogenesis and thereby subsequently reduce sun (UV) damage to UV light-exposed skin in preliminary research and human clinical trials.〔(【引用サイトリンク】url=http://azcc.arizona.edu/node/2729 )〕 Its amino acid sequence is Ac-Ser-Tyr-Ser-Nle-Glu-His-D-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2, and it is additionally known as ()-α-MSH, which is sometimes abbreviated as NDP-MSH or NDP-α-MSH (especially in the scientific literature). Afamelanotide is the International Nonproprietary Name for the molecule ()α-MSH initially researched and developed as melanotan-1 and later, CUV1647 (by Clinuvel). A marketing trade name for one brand of afamelanotide was approved in 2010 by the European Medicines Agency (EMA) Name Review Group (NRG) and the agency's Committee for Medicinal Products for Human Use (CHMP) as Scenesse (pronounced "sen-esse"). On May 5, 2010 the Italian Medicines Agency (AIFA, or Agenzia Italiana del Farmaco) became the first governmental health organization ever (even before the drug received approval in Europe) to authorize afamelanotide as a medicine for therapeutic treatment of Italian citizens to reduce painful dermal photosensitivity stemming from the orphan disease erythropoietic protoporphyria (EPP). This approval allowed the drug to be immediately available for prescription in Italy and reimbursable under the country's national health system. Authorities in Switzerland have also allowed prescription of the drug for EPP with reimbursement approved by two unnamed insurers.〔http://www.porphyriafoundation.com/node/565〕 Afamelanotide is currently being trialed in the form of a "grain of rice"-sized bioabsorbable subcutaneous implant as a potential therapeutic photoprotection-inducing agent for a series of light-related skin indications as well as a potential dermal repigmentation agent for vitiligo. Afamelanotide, as of October 24, 2014, has been approved by the EMA in Europe for the treatment of EPP. Clinuvel now intends to seek approval of afamelanotide in the United States.〔 Unlicensed and untested powders sold as "melanotan" are found on the Internet and are reported to be used by tens of thousands of members of the general public for sunless tanning. Multiple regulatory bodies have warned consumers that the peptides may be unsafe and ineffective in usage, with one regulatory agency warning that consumers who purchase any product labeled "melanotan" risk buying a counterfeit drug.〔 Clinuvel Pharmaceuticals, the developer of afamelanotide, and medical researchers have warned consumers that counterfeit products sold using the names "melanotan I and II", could "pose a hazard to public health".〔(Clinuvel Position Statement ) on counterfeit products. February 10, 2009.〕 Clinuvel has stated publicly that products sold online as "melanotan" are not afamelanotide. ==Historical development== ()-α-MSH was first synthesized at the University of Arizona. Researchers there knew that one 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 the body's natural photoprotective skin pigmentation (a tan) prior to UV exposure. The body's naturally occurring hormone α-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 means of sunless tanning. What they found was that while it appeared to work, natural α-MSH had too short a half life in the body to be practical as a therapeutic drug. The team then searched for a more potent and stable alternative. After synthesizing and screening hundreds of molecules, the researchers, headed by Victor J. Hruby and Mac E. Hadley, found a peptide, ()-α-MSH, that was approximately 1,000 times more potent than natural α-MSH. They dubbed this new peptide molecule "Melanotan" (later Melanotan-1, now known as afamelanotide). They subsequently developed another analog, Ac-Nle-''cyclo''()-NH2), which they called "Melanotan II". The scientists hoped to use these peptides to prevent melanoma by stimulating the body's natural pigmentary mechanism to create a tan without exposure to harmful levels of UV radiation. This in turn, they hypothesized, could reduce the potential for skin damage in the tanning population that could lead to skin cancer. The scientists licensed their patented peptides, via a technology transfer company, to a number of biotechnology companies intent on developing them into drugs. Afamelanotide (formerly the proprietary CUV1647) has been tested, in an implant delivery formulation, and clinically trialed by the Australian company Clinuvel Pharmaceuticals, for a series of conditions affecting the skin including erythropoietic protoporphyria (EPP), polymorphous light eruption (PMLE), solar urticaria (SU), phototoxicity associated with systemic photodynamic therapy and actinic keratosis (AK) and squamous cell carcinoma skin cancer in patients who have received organ transplants, vitiligo and Hailey Hailey disease. The drug has previously been tested in polymorphous light eruption (PMLE), solar urticaria (SU) and phototoxicity associate with systemic photodynamic therapy.〔http://onlinelibrary.wiley.com/doi/10.1111/ced.12203/abstract〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Afamelanotide」の詳細全文を読む スポンサード リンク
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