Peptides now represent one of the fastest growing classes of new drugs. Though they currently account for only 2% of drugs on the market, they comprise roughly 50% of drugs in the pipelines of major drug manufacturers. The market for peptide drugs is now growing at a compound annual rate of 7.5% and is estimated to be worth in excess of $13 billion by 2010.
Great. So what is a peptide?
A peptide is a molecule formed by joining two or more amino acids. Those that contain more than 50 amino acids are characterized as proteins (polypeptides). They are present in every living cell and possess a variety of cellular and physiological functions, acting as enzymes, hormones, antibiotics and receptors. Drug discovery can be seen as a 3- step process. 1) analysis of protein behavior 2) development of molecules of similar shape and charge that will bind to the specific protein to modulate that behavior and 3) testing of molecule’s effect on underlying protein. The use of peptides aids in each step and thus, they are seen as a vital tool in the future of drug discovery.
Most drugs are known as small molecule drugs, and peptides differ in several important ways. Peptides are more potent, less toxic and more specific in their ability to bind to protein targets. Toxicity is a key reason that the pipelines of many pharmaceutical companies are quite thin. Many promising new drug candidates that show excellent efficacy in preclinical animal models fail when it is found that they cause toxic effects in humans. With these advantages, why has the peptide drug market more or less stalled since insulin (a peptide hormone) was developed in 1959? Costs.
Natural peptides have a short half life and often fail to thrive in vivo – making their manufacture quite expensive. Only very recently have advances in sustainable synthetic peptides and the use of peptide libraries (somewhat similar to gene mapping) lowered the price tag. The cheaper costs and aforementioned toxicity issues have led to renewed interest in the use of peptides for use not only as therapeutics, but for vaccines, diagnostics and drug delivery devices.
Compugen (Nasdaq: CGEN) of Tel Aviv recently released news of a novel peptide therapeutic for the treatment of retinopathy, a serious eye condition caused by overgrowth of blood vessels that is the leading cause of adult onset visual disability and blindness. Compugen has a peptide drug discovery division, “Blockers of Disease-Associated Conformation” (DAC Blockers) that attempts to identify peptides that block proteins from adopting their disease-associated conformations. Albany Molecular Research (Nasdaq:AMRI) – I will let you figure out which in city the company is based – is preparing an IND submission for a drug to treat obesity. The Company has isolated Melanin concentrating hormone (MCH), a potent appetite stimulating peptide known to exert an effect on food intake and body weight regulation, and developed a drug to modulate its impact.
Commonwealth Biotechnologies* (Nasdaq: CBTE) is the world’s largest supplier of research grade peptides and a leader in value added peptide drug discovery consulting. The Company is the proverbial seller of picks and shovels – it has partnered with Genzyme Pharmaceuticals to develop synthetic peptides, peptide libraries, assay and protein-antibody mapping – that drug companies will use for their peptide research.
The increased use of protein therapeutics will lead to greater opportunities for drug delivery firms. The market is largely immediate release via injection but pharma companies will look to sustained release and oral formulations to differentiate themselves from a crowded market. http://www.emisphere.com/pdfs/Drug_Dlvry_Tech-Protein-Peptide-3-09.pdf. Drug delivery technology firm SurModics Inc. (Nasdaq: SRDX) of Eden Prairie, MN is developing injectable products for 4 to 6 month delivery cycles. It has partnered with Genzyme to perform drug delivery-based screening on lead peptides in discovery to provide the optimum peptide for use in controlled delivery. Emisphere Technologies (OTC: EMIS) of Cedar Knolls, NJ has a proprietary technology to develop novel oral forms of poorly absorbed compounds. Its Eligen® technology protects peptide molecules from dissolving in the gastrointestinal tract before absorption occurs.
*client of Allen & Caron, publisher of this blog