Biopharmaceuticals are increasingly important in the pipelines of major pharmaceutical companies, but key technical issues
exist in bringing certain biopharmaceuticals such as peptides to market. Improving delivery technologies, developing peptides
with increased stability and half-life, and synthesizing long-chain peptides are some challenges in advancing commercialization.
Compared with other therapeutic proteins, peptides are a niche area. Roughly 430 proteins are in clinical development compared
with130 peptides, and 70 proteins are in Phase III and registration compared with 20 peptides (1).
Lured by potential in clinical efficacy, however, the pharmaceutical majors and emerging drug companies are building their
pipelines with peptide-based drugs and with technology to optimize the synthesis and delivery of peptides.
Pharma majors target peptides
A case in point is Pfizer, Inc. (New York, NY), which earlier this year agreed to acquire BioRexis Pharmaceutical Corporation (King of Prussia, PA), a biopharmaceutical company with several diabetes drug candidates and a protein-engineering technology
based upon human transferrin designed to provide therapeutic agents with longer duration of action than synthetic peptides.
BioRexis's technology produces biopharmaceuticals by genetically engineering protein and peptide drugs into the scaffold of
a natural variant of the human plasma protein transferrin. The engineered fusion protein is designed to enhance drug half-life
from minutes or hours to several days or weeks, thus overcoming the problem of short half-life associated with peptide drugs.
The engineered-fusion technology allows the drugs to be manufactured in yeast and genetically fuses therapeutic proteins and
peptides to the N or C terminus, or both, of the carrier protein, nonglycosylated transferrin, according to the company.
BioRexis's lead candidate is a fusion of the well-known glucagon-like peptide (GLP-1), a 30-amino-acid peptide, to transferrin,
for treating Type 2 diabetes. Pfizer also is developing a GLP-1 compound (PF 734200) to treat diabetes.
Sanofi-Aventis and Wyeth.
Zealand Pharma (Copenhagen, Denmark) is another company specializing in peptide development and technology. Its stabilization of peptide
("SIP") technology is designed to increase biological half-life and improve product stability. Zealand is partnered with Sanofi-Aventis SA (Paris, France) for developing AVE0010, a GLP-1 for treating Type 2 diabetes, and with Wyeth (Madison, NJ) for developing rotigaptide, a peptide cardiovascular drug.
Eli Lilly and Company (Indianapolis, IN) has a global development and commercialization pact with Amylin Pharmaceuticals, Inc. (San Diego, CA) for "Byetta" (exenatide), a 39-amino-acid peptide amide with incretin-mimetic actions to treat Type 2 diabetes.
The drug received US regulatory approval in 2005 and European approval in 2006.
Amlyin obtains exenatide, the active ingredient in Byetta from peptide supplier Bachem (Torrance, CA) and Mallinckrodt, Inc. (St. Louis, MO) under long-term supply agreements , according to Amylin's 2006 annual report.
The Eli Lilly–Amylin pact includes the development of a long-acting release (LAR) formulation of exenatide. Amylin is working
with Alkermes, Inc. (Cambridge, MA) to develop a once-weekly dosing of exenatide. Amylin expects to complete the commercial-scale manufacturing
process for the LAR formulation of exenatide and commission a new manufacturing facility in West Chester, Ohio in the second
half of 2008, according to Amylin's annual report.