Organogenesis Inc. said Friday that this month it will beginexpanded preclinical feasibility studies of ligamentreplacement using its dense fibrillar collagen (DFC) technology.

The studies will be conducted at the Memorial Medical Centerin Long Beach, Calif.

Results from an initial feasibility study completed recently atTufts University School of Veterinary Medicine demonstratedthat implanted collagen constructs provided for guided tissueregeneration, resulting in the formation of new tissue thatclosely resembles normal ligaments.

The study involved the use of DFC for two orthopedicapplications: tendon repair and tendon and ligamentreplacement.

Thomas Tully, president and chief operating officer of theCambridge, Mass., company, said that although other companieshave attempted to use collagen for ligament repair andreplacement, Organogenesis is the only company to besuccessful.

"In other attempts, an appropriate collagen material wasn'tpresent," said Tully. The collagen wasn't strong enough in thesecases to be durable in ligament treatment, he said.

DFC was discovered by Organogenesis scientists working onGraftskin, the company's collagen-based skin replacementtherapy, according to Jennifer Pierce, director of corporatecommunicatins. They found that Organogenesis' proprietaryacid bath extraction method allowed them to remove collagen,which is taken from the hooves of calves, in a much strongerform than previously available.

Other companies "cleave" the ends of the collagen molecules toextract the compound, which results in a weaker and lesspliable product than Organogenesis has developed, Pierce said.

DFC can be manipulated into a variety of forms, such asthreads, knits, yarns, weaves, cylinders and sheets. When it isused for ligaments, DFC resembles a steel cable wrapped incollagen to give it strength and durability, Pierce said.

In ligament repair therapy, a sheath -- a woven skin of DFC --is placed over the tendon and sutured to each end. Thistechnique spreads the stress over a much wider area and helpsthe tendon recover its original strength.

Ligament replacement therapy uses a structure made frombraided DFC as a tendon or ligament prosthesis. The strength ofthe DFC will permit the device to remain intact and functionalwhile it is gradually "remodeled" -- replaced by native collagenduring the natural cycle of protein turnover and reshaped toresemble its original structure. As the remodeling takes place,the structure is reabsorbed by the body.

Tully said he hopes that by the end of next year -- assumingthat the studies produce positive results -- the company willsubmit an investigational device exemption (IDE) to the FDA,and will begin clinical trials soon thereafter.

Tully told BioWorld that 250,000 ligament procedures areperformed annually in both the U.S. and Europe.

-- Michelle Slade Associate Editor

(c) 1997 American Health Consultants. All rights reserved.