Bone-forming graft

Details Bone-forming graft Bone-forming graft

1997-03-25

1998-11-03

Page, Thurman K.

Drug, bio-affecting and body treating compositions

Preparations characterized by special physical form

Implant or insert

623 12, 623 16, 523115, A61F 200

Patent

active

058304932

DESCRIPTION:

BRIEF SUMMARY
This application is a 35 USC 371 of PCT JP95/61970 filed Sep. 28, 1995.
1. Technical Field
The present invention relates to a bone-forming graft containing a bone morphogenetic protein, and a composite porous body which may be used as a carrier of the bone morphogenetic protein.
In particular, the present invention relates to a bone-forming graft which comprises a bone morphogenetic protein carried on a composite porous body, said composite porous body comprising a porous frame of a bioabsorbable hydrophilic material and a surface layer of a bioabsorbable polymer material; as well as to the composite porous body which is useful as a carrier for the bone morphogenetic protein.
2. Background Art
Bone morphogenetic protein (BMP) is an active protein which acts on the undifferentiated mesenchymal cells in the subcutaneous or muscle tissue to cause the differentiation thereof into chondroblasts or osteoblasts, and the formation of cartilage or bone. BMP was found in bovine demineralized bone matrix as a substance exhibiting ectopic bone inducing activity, but had not been purely isolated and therefore the concrete structure thereof had remained unknown. By the genetic engineering technique, however, the gene encoding the human BMP was cloned and the amino acid sequence thereof was elucidated. Further, it was found that the human BMP comprises a family of plural closely-related proteins having homologous amino acid sequences. Various types of recombinant human bone morphogenetic proteins Acad. Sci. USA, Vol. 87, pp 2220-2224 (1990); Progress in Growth Factor Research, Vol. 1, pp. 267-280 (1989); Japanese National-phase Publications No. 2-500241, No. 3-503649 and No. 3-505098; WO91/18098, WO92/05199, and WO93/09229!. Further, the rhBMPs were produced from transformants.
Even before the structure of the BMP was elucidated, various methods were proposed to use the BMP for treatment of damage, loss, or hypoplasia of bones or cartilage. Such proposals have been increased along with the production of recombinant BMP. When the BMP is used, it is extremely difficult to induce bone formation by locally implanting the BMP alone, and so the BMP is generally carried on a carrier and then the whole is locally implanted. The main purpose is not to disperse the BMP from the implanted site but to hold the BMP thereat at least for several days to several weeks, because the BMP requires such a period of time for local bone formation. The carrier is implanted in a living body together with the BMP as above, and thus requires low toxicity, low carcinogenicity, low antigenicity and so without affecting the BMP activity. Further, easy availability and, in some cases, biodegradability are desired.
Hitherto, for example, an implantable material wherein BMP is carried on a carrier of atelocollagen (Japanese Unexamined Patent Publication No. 62-89629), an implantable material prepared by impregnating a ceramics support with BMP and collagen carrier (Japanese Unexamined Patent Publication No. 60-253455), and a composition comprising rhBMP, a porous biodegradable polymer and the patient's blood (U.S. Pat. No. 5,171,579), or the like were proposed.
However, a graft composed of only BMP and a collagen carrier does not have sufficient formability nor strength. Further, such a graft quickly decomposes in the living body, and thus the shape cannot sufficiently be maintained or bone formation was not necessarily sufficient. If a non-decomposable or slowly decomposable substance (e.g., a ceramic material) is used as a support or such a substance is mixed with the carrier to improve the formability and cohesiveness in the living body, there is the problem that such a substance remains without being resorbed by the body, which inhibits formation of uniform bone tissues or there is a possibility that the remaining carrier causes bone resorption due to re-modeling of bone, etc. Furthermore, for the composition comprising porous biodegradable polymer particles and the patient's blood, an improvement was desired in terms of the workability and adjustab

REFERENCES:
patent: 4713076 (1987-12-01), Draenert
patent: 5133755 (1992-07-01), Brekke
patent: 5520923 (1996-05-01), Tjia et al.
patent: 5665114 (1997-09-01), Weadock et al.

Affiliated with

Also associated with

Rating

Bone-forming graft does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Bone-forming graft, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Bone-forming graft will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-686821