Protein Polymer Presents Data on Tissue Engineering, Surgical Adhesives
and Protein Polymer Hydrogels
SAN DIEGO, April 27, 1998 -- Protein Polymer Technologies,
Inc. (Nasdaq: PPTI), presented on Saturday data on the comparative performance
of the Company's surgical adhesives and sealants, and on the mechanical
properties of its Silk-Elastin hydrogels being developed as tissue augmentation
agents in the treatment of female stress urinary incontinence and for cosmetic
and reconstructive medical procedures. Previously, the Company presented
results from a study of tissue engineered wound healing matrices. All three
presentations were made at scientific sessions of the 24th Annual Meeting
of the Society for Biomaterials in San Diego, CA.
Joseph Cappello, Ph.D., Vice President of Research and
Development, presented test results from a comparative study of the bond
strengths of different types of surgical adhesives and sealants. In
this study, PPTI's adhesive was found to be stronger than fibrin sealants
and cyanoacrylate adhesives as well as creating more flexible and extensible
bonds, all conditions important to successful wound closure and healing.
PPTI's adhesives are engineered to chemically cross-link to the body's tissue,
enabling the creation of bonds between tissue layers that are superior in
both strength and flexibility to other sealant and adhesive products.
PPTI's engineered adhesives are being developed to replace or augment the
use of sutures and staples in a variety of surgical wound closure applications.
Dr. Cappello, in a presentation last Thursday entitled
"Protein Polymer Porous Scaffolds for Tissue Engineering," discussed
the results of in vivo animal implant studies in which PPTI's resorbable
porous sponges were found to increase the rate of wound healing. As
reported, the results were due to the ability of the sponges to provide
more uniform surface area for new granulation tissue to infiltrate, causing
the cellular re-epithelialization of the sponge, and thus leading to the
deposition of new collagen within the sponge's pores. In these studies,
PPTI's sponges demonstrated excellent biocompatibility and persisted longer
during the wound healing process, as compared to collagen sponges.
PPTI's sponges are expected to be used as scaffolds for the regeneration
of tissues.
Stephen Kennedy, Ph.D., a Senior Research Scientist at
PPTI, Saturday presented the results of a series of studies on the mechanical
properties of hydrogels from Silk-Elastin protein block copolymers.
PPTI's injectable hydrogel technology relies on the ability of these unique
polymers to be injectable as a liquid at room temperature, and then to irreversibly
form a gel at body temperature. By controlling both the structure
of the protein blocks and conditions involved in product formulation, Dr.
Kennedy hypothesized that the rate of gel formation, the strength of the
gels, and the rate or degree of resorption can be predicted and controlled.
These hydrogels are being developed as bulking agents for cosmetic, reconstructive
and urological applications. PPTI anticipates obtaining FDA's approval
of an IDE to begin pilot clinicals for urological indications before the
end of 1998, and clinical testing of the cosmetic/reconstructive indications
to begin in early 1999.
Protein Polymer Technologies, Inc., a San Diego-based
biotechnology company, has a technology platform that allows the creation
of a number of different classes of biocompatible polymers that enable cell
growth, promote the regeneration of tissue, bond to synthetic surfaces,
and are resorbed by tissue at controlled rates. PPTI's lead programs
include a new generation of surgical adhesives and sealants to replace or
augment the use of sutures and staples, and unique hydrogels that can be
injected as liquids, but form pliable, irreversible gel structures once
body temperature is reached.
