Pralmorelin

Abstract

Pralmorelin [GPA 748, GHRP 2, growth hormone-releasing peptide 2, KP-102 D, KP 102 LN] is an orally active, synthetic growth hormone-releasing peptide from a series of compounds that were developed by Polygen in Germany and Tulane University in the US.

Researchers at Tulane University led by Dr Cyril Bowers synthesised a series of small highly active peptides ranging in size from 3–5 amino acids or partial peptides that were suitable for a variety of administration formats (subcutaneous, buccal, oral, depot). These peptides mimic the actions of ghrelin, a 28 amino acid octanoyl peptide that regulates the release of growth hormone (GH), and may play an important role in bone and muscle growth, food intake and possibly improve recovery from injury.

The use of pralmorelin as a diagnostic agent for GH deficiency is based on its ability to markedly increase plasma levels of GH in healthy subjects irrespectively of gender, obesity or age. However, in patients with GH deficiency, the effect of pralmorelin on GH levels is significantly lower compared with healthy controls. Analysis of the receiver-operating characteristics curve provided the cut-off threshold value for the GH peak of 15.0 μg/L for the identification of patients with GH deficiency from those of healthy controls.

Kaken acquired worldwide manufacturing and marketing rights to pralmorelin, and then sublicensed it to Wyeth (formerly American Home Products) for the US and Canada. Kaken retains rights to pralmorelin in Japan. On 11 March 2002 American Home Products changed its name and the names of its subsidiaries Wyeth-Ayerst and Wyeth Lederle to Wyeth.

Kaken also granted exclusive sublicense options in Africa, Australia, Europe, Latin America and New Zealand to unspecified partners.

Pralmorelin as KP-102 D [KP-102D] is currently awaiting approval in Japan as a diagnostic agent for hypothalamo-pituitary function. It is planned to be launched in Japan for this indication in 2004. Pralmorelin is also undergoing phase II clinical trials with Kaken in Japan for short stature (pituitary dwarfism) as KP-102 LN [KP-102LN]. Its launch for the treatment of short stature is planned for 2009 (Kaken, Annual Report 2003).

The agent was undergoing phase II trials in the US for the treatment of GH deficiency with Wyeth; however, it appears that its development was discontinued.

Tulane University was granted a US Patent (6,468,974 issued in October 2002), as well as patent protection in Europe and other countries for a series of synthesised GH-releasing peptides.