By Mary Welch

Principia Pharmaceutical Corp. is a new company developing a technology platform that uses recombinant albumin fusion proteins to provide sustained activity and improved stability.

"We are a development company that produces proteins with sustained activities from products already proven as well as ones that we will develop," said Christopher Prior, president and founder of the King of Prussia, Pa.-based company. "We have the worldwide licensing rights to the technology from Centeon LLC [also of King of Prussia]. The albumin-based fusion protein technology was not part of their business focus and we have the worldwide licensing rights in exchange for a licensing fee, equity, milestones and royalties."

The start-up's platform is based on genetically fusing a therapeutic protein to human albumin, the most copious blood protein and a natural carrier molecule with a circulation lifetime of several weeks. "It's a benign protein with no intrinsic activity," he said. "It's a perfectly natural carrier."

Principia's albumin-based fusion proteins can be produced in mammalian cell culture, where correct glycosylation of the proteins is essential. For products not requiring glycosylation, a proprietary yeast expression system secretes fusion products in the fermentor.

"We don't have to chemically modify our products, we just purify them - again, more convenient, safe and less costly," he added.

"Albumin confers excellent stability in liquid form, which also offers marketing advantages over competitive products," Prior said. "Overall, we believe our technology, by reducing the number of treatments and toxicity, will help lower medical costs."

The company, which now has seven employees, has three products in the preclinical stage. It intends to file investigational new drug applications for two of them by next June; the other by the third quarter of 2000. Its initial focus will be on proteins for the treatment of cancer, viral diseases and growth deficiencies.

Two of the albumin-based fusion constructs in the yeast system are available for immediate development. One is a human growth hormone (HA-hGH), the other an alpha-interferon (HA-a-INF). The third, either interleukin 2, G-CSF, Hirudin, or insulin, is still under selection for clinical development.

The company's business plan is to fuse albumin with already approved products "to make them even better by extending their half-life and reducing toxicity," Prior said. The second target is peptides. The third is to provide enabling technology for discovery and optimization of antibiotics.

"Since we intend to fuse products [with drugs] whose therapeutic targets and efficacy are already known, we eliminate years of research from the product development path," Prior said. "We believe we will attract licensing partners, especially large pharmaceutical companies whose patents may be running out and need to do something to extend the product's life through patent extensions."

Prior is the former general manager of The Immune Response Corp., of Carlsbad, Calif. The company's chairman, Frederick Kyle, is the former president of worldwide commercial operations for SmithKline Beecham Pharmaceuticals. Another co-founder is Richard Gore, former senior manager at Immune Response.

The company was funded with seed money from Health Care Ventures Inc., of Princeton, N.J., and a second round already is in the works.

"We're making inroads with investors and we've had serious inquiries from three potential partners so far," Prior said. "Longer-acting proteins or drugs in combination with drug delivery will provide significant therapeutic and cost benefits. Development companies, like Principia, will make major contributions in this area."