RhBMP-2

RhBMP-2 Uses, Dosage, Side Effects, Food Interaction and all others data.

RhBMP-2 is a recombinant human bone morphogenetic protein-2 (rhBMP-2) derived from a recombinant Chinese Hamster Ovary (CHO) cell line . It is implanted in patients undergoing bone surgeries or those with fractures. BMPs are subfamily of the transforming growth factor-β (TGF-β) superfamily that have different actions on the bone matrix . BMP-2 is a potent osteoinductive protein that plays a critical role in the differentiation of osteoprogenitor cells into osteoblasts, thus promoting bone and cartilage formation . Through enhancing osteogenesis at the site of implantation, dibotermin alfa accelerates the healing of open tibial shaft fractures and reduces the need for secondary intervention . In a prospective clinical study of patients with an open tibial fracture, administration of dibotermin alfa resulted in faster fracture- or wound-healing, significantly fewer secondary invasive interventions, and reduced infection rate post-operation . RhBMP-2 was approved by the EMA in 2002 as Inductos for implantation matrix. In 2004, it was approved by the FDA and is marketed as Infuse. In Infuse, rhBMP is a disulfide-linked dimeric protein molecule with two major subunit species of 114 and 131 amino acids. Each subunit is glycosylated with high-mannose-type glycans .

RhBMP-2 promotes bone and cartilage formation through anabolic effects in human osteoblastic cells . Radiographic, biomechanical and histologic evaluation of the induced bone at the site of implantation supports that induced bone from dibotermin alfa therapy is capable of biological and biochemical function as native bone and repair abilities .

RhBMP-2
Uses
Dosage
Side Effect
Precautions
Interactions
Uses during Pregnancy
Uses during Breastfeeding
Accute Overdose
Food Interaction
Half Life
Volume of Distribution
Clearance
Interaction With other Medicine
Contradiction
Storage

Trade Name	RhBMP-2
Generic	Dibotermin alfa
Dibotermin alfa Other Names	BMP 2, BMP-2, Bone morphogenetic protein 2, Bone morphogenetic protein 2 (human recombinant rhBMP-2), Dibotermin alfa, Dibotermina alfa, rhBMP-2
Type
Groups	Approved, Investigational
Therapeutic Class
Manufacturer
Available Country
Last Updated:	September 19, 2023 at 7:00 am

Uses

indicated for the treatment of acute tibia fractures in adults, as an adjunct to standard care using open fracture reduction and intramedullary unreamed nail fixation .
indicated for single-level lumbar interbody spine fusion as a substitute for autogenous bone graft in adults with degenerative disc disease who have had at least 6 months of non-operative treatment for this condition .

RhBMP-2 is also used to associated treatment for these conditions: Tibial Fractures, Single-level lumbar interbody spine fusion

How RhBMP-2 works

In the same pathway shared by endogenous BMPs, recombinant human BMP-2 (rhBMP-2) binds and initiates intracellular signal cascade through an oligomeric transmembrane receptor complex formed by type I and II serine/threonine kinase receptor proteins . These BMP receptors are expressed on the surface of mesenchymal cells and upon binding of BMP-2 to the BMP receptor type II, type II receptor phosphorylates and activates type I receptor. Type I receptor may also undergo autophosphorylation. Activated BMP type I receptor then phosphorylates intracellular effector proteins, the receptor-regulated Smads (R-Smads) . Smad1, Smad 5 and Smad 8 associate with the Co-Smad, Smad4 and once activated via complex formation, they translocate to the nucleus where they associate with other transcription factors and bind promoters of target genes to control their expression . This ultimately results in bone formation at the site of implantation. RhBMP-2 causes mesenchymal cells to differentiate into cartilage- and bone-forming cells. Implantation of dibotermin alfa in trabecular bone results in transient resorption of the bone surrounding the implant, followed by replacement of degraded matrix by newly differentiated cells .

In human bone cells isolated from adult mandibulae, recombinant human BMP-2 (rhBMP-2) was shown to stimulate the activity of early biomarkers of osteoblast differentiation, including alkaline phosphatase and parathyroid hormone (PTH)-dependent 3', 5'-cyclic adenosine monophosphate accumulation . At concentrations of 500 ng/mL, rhBMP-2 also enhanced the mRNA expression level of PTH/PTH related-peptide receptor in human bone cells . There was evidence that rhBMP-2 inhibits 1,25-dihydroxyvitamin D3-induced osteocalcin synthesis at both the mRNA and protein level. rhBMP-2 also significantly suppressed MMP-1 production and MMP-1 mRNA expression at concentrations exceeding 500 ng/mL .

Toxicity

Supportive treatment is recommended in case of overdose. Use of Inductos in patients undergoing cervical spine surgery in amounts lower than or similar to those for lumbar interbody fusion has been associated with reports of localised oedema severe enough to result in airway compromise .

There is no evidence of significant hazards on humans based on non-clinical data of acute and repeated exposure toxicity and genotoxicity studies . In reproductive toxicity studies in rats, intravenous administration of dibotermin alfa was associated with increased fetal weight and increased fetal ossification. The clinical relevance of this effect is unknown . In human tumour cell lines in vitro, dibotermin alfa did not display any potential for promotion of tumour growth or metastasis . Studies investigating the carcinogenicity of dibotermin alfa have not been conducted.

Elimination Route

RhBMP-2 is active at the site of implantation with no detection in the serum. In rat studies with radiolabelled dibotermin alfa, the mean residence time at the site of implantation was 4-8 days . Peak levels of circulating dibotermin alfa (0.1% of the implanted dose) were observed within 6 hours following implantation .

Half Life

When injected intravenously, the terminal half-life of dibotermin alfa was 16 minutes in rats and 6.7 minutes in cynomolgus monkeys .

Clearance

At the site of implantation, dibotermin alfa is expected to be slowly released from the matrix and rapidly cleared when taken up into the systemic circulation .

Elimination Route

As recombinant human bone morphogenetic protein-2 (BMP-2), dibotermin alfa is expected to undergo nonspecific protein degradation pathway shared by endogenous BMP-2.