Company: OSRH
Filing Date: 2025-01-29
Form Type: S-4/A
Source: 0001213900-25-007923
Chunk: 414

Company: OSR Holdings, Inc.
Filing Date: 2025-01-29
Form: S-4/A
Chunk 414
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 a synthetic bone graft in granular form. The AB protein (AB204) is a synthetic protein, created by fusing Activin and BMP -2, both members of the BMP (Bone Morphogenetic Protein) family, growth factors by Darnatein’s segmental reassembly technology. AB204 combines BMP’s type II receptor binding with activin A’s high -affinitytype II receptor binding. It induces significantly greater and longer -lastingSmad 1/5/8 phosphorylation in osteoblastic cells compared to BMP2, promoting mineral calcium nodule formation crucial for bone apatite formation. Unlike BMP2, AB204 is unaffected by noggin by design and also inhibits activin signaling, which further enhances its bone formation and is noteworthy since activin antagonism itself can promote bone formation. When used in conjunction with existing synthetic bone grafts, it facilitates the generation of new bone and can aid in fracture healing. The synthetic bone graft uses approved products and is composed of hydroxyapatite and beta -tricalciumphosphate, with internal pores connected in a three -dimensionalstructure. By coating a highly bioactive and absorbable ß -TCPon an HA scaffold that can support structurally for a long period with excellent biocompatibility and slow biodegradation, it enables rapid initial bone bonding and long -termsupport dynamics. DRT -102pre -clinicalstudy for toxicity measurement in animal models The toxicity test of DRT -102was conducted with multiple institutions including KTR (Korea Chemical Corporation), KIT (Korea Institute of Toxicology), and ChemOn. The purpose of this study is to evaluate the potential toxicity and determine the dose levels for a repeated toxicity study of DRT -102, when intravenously administered to rats and Beagles(non -rodents) The table below outlines the type, species, purpose and results of the pre -clinicaltoxicology studies so far.

| Type of study                                                   |     | Species     |     | Purpose                                                                                                                                                            |     | Results                                                                                                                                                                                                                                                                                                    |     | Date       |     | Institution |
| Dose Range Finding Study: 2-Week Repeated Intravenous Injection |     | Sprague-    
 Dawley Rats |     | To evaluate the potential toxicity and determine the dose levels for a repeated toxicity study of DRT-102, when intravenously injected to the Sprague-Dawley rats. |     | No deaths were observed. A slight dose-dependent increase in the absolute and relative weights