Abstract Pharmaceutically acceptable, non-immunogenic compositions are formed by covalently binding atelopeptide collagen to pharmaceutically pure, synthetic, hydrophilic polymers via specific types of chemical bonds to provide collagen/polymer conjugates. The atelopeptide collagen can be type I, type II or type III and may be fibrillar or non-fibrillar. The synthetic hydrophilic polymer may be polyethylene glycol and derivatives thereof having a weight average molecular weight over a range of from about 100 to about 20,000. The compositions may include other components such as liquid, pharmaceutically acceptable, carriers to form injectable formulations, and/or biologically active proteins such as growth factors. The collagen-polymer conjugates of the invention generally contain large amounts of water when formed. The conjugates can be dehydrated to form a relatively solid object. The dehydrated, solid object can be ground into particles which can be suspended in a non-aqueous fluid such as an oil and injected into a living being for the purpose of providing soft tissue augmentation. Once in place, the particles rehydrate and expand in size five fold or more.
A method for augmenting a tissue in a mammal, comprising the steps of: providing a collagen-polymer conjugate comprising reconstituted collagen chemically conjugated by a covalent ether bond to a non-immunogenic synthetic hydrophilic polymer; dehydrating the polymer in order to form a substantially solid material; grinding the solid material into particles; forming a suspension by combining the particles with a non-aqueous carrier; administering the suspension at a site in need of augmentation; and allowing the non-aqueous carrier to diffuse away and allowing the particles to rehydrate.
Claim 2
Independent Claim
85 words
A method for augmenting a tissue in a mammal, comprising the steps of: providing a collagen-polymer conjugate comprising reconstituted collagen chemically conjugated by a covalent ether bond to a non-immunogenic synthetic hydrophilic polymer; dehydrating the polymer in order to form a substantially solid material; grinding the solid material into particles; forming a suspension by combining the particles with a non-aqueous carrier; administering the suspension at a site in need of augmentation; and allowing the non-aqueous carrier to diffuse away and allowing the particles to rehydrate.
Claim 3
Dependent Claim
12 words
The method of claim 1, wherein the synthetic polymer is polyethylene glycol.
Claim 4
Dependent Claim
22 words
The method of claim 2, wherein the polyethylene glycol has a molecular weight in the range of about 100 to about 20,000.
Claim 5
Dependent Claim
23 words
The method as claimed in claim 1, wherein the non-aqueous carrier is a naturally-occurring, fatty acid ester containing 12 to 22 carbon atoms.
Claim 6
Dependent Claim
24 words
The method as claimed in claim 1, wherein the particles have a particle size in the range of about 0.01 mm to 0.5 mm.