Bone-Targeted Drug Delivery Systems

CD Bioparticles' state-of-the-art drug development services provide cutting-edge solutions aimed at the development of therapeutics targeting the bone. With a dedicated focus on utilizing advanced technologies such as nanocarriers, ligand modifications, and comprehensive evaluations for activity and efficacy, we ensure the rapid development and efficient delivery of targeted treatments for various bone-related diseases and conditions. We can provide you with reliable and professional services to improve the performance of your bone targeted drugs with better effectiveness, stability and biocompatibility.

Introduction to Bone-Targeted Drug Delivery Systems

The skeletal system is vital for maintaining body structure and support, comprising bones, ligaments, cartilage, and connective tissues. However, bone-related diseases, such as osteoporosis, osteomyelitis, multiple myeloma, osteosarcoma, and bone metastasis, present significant challenges due to the limited blood supply and poor drug penetration of the bone itself, particularly in vascular and cartilage areas. This often requires high-dose drug administration to maintain optimal blood drug concentration, leading to systemic toxic side effects. In response to these challenges, bone-targeted drugs have emerged as a promising approach.

In the context of non-specific bone-targeted drug delivery systems, there exist physical-chemical targeted and passive targeted drug delivery systems. Physical-chemical targeted drug delivery systems entail methods such as magnetic targeting, thermal-sensitive targeting, pH-sensitive targeting, and photo-sensitive targeting. On the other hand, passive targeted drug delivery systems use specialized carriers such as liposomes, nanoparticles, nanocapsules, and microparticles to enclose drug compounds. These carrier vehicles can either accumulate in bone tissues via physiological means or be absorbed and conveyed to the bone through the mononuclear phagocyte system. With the advent of nanotechnology, a more specific approach to active targeting drug delivery systems for bone diseases is now feasible.

Figure 1 Internal structure of a bone^[1]

The Specific Features of Bone-Targeted Drug Delivery Systems:

In the field of targeted drug delivery to the skeletal system, two highly effective approaches have been identified: cell-specific targeting and whole bone tissue targeting. The former strategy involves targeting bone marrow mesenchymal stem cells and osteoclasts, while the latter targets the bone tissue primarily composed of hydroxyapatite. Nanocarriers represent a highly promising approach to improve drug delivery in bone targeting systems. These small-scale carriers help improve drug solubility, modulation of release rate, protection against enzymatic degradation, longer circulation times, and reduced drug toxicity. Different kinds of nanocarriers are used in bone targeting drug delivery systems, including inorganic nanocarriers such as silica particles, titanium, nanotubes, gold nanoparticles, and calcium phosphate nanoparticles, and organic nanocarriers such as chitosan nanoparticles, polymer nanoparticles, and lipid nanoparticles. While inorganic nanocarriers are usually used for local administration, organic nanocarriers are typically used for systemic administration in bone targeting drug delivery systems.

The Applications of Bone-Targeted Drug Delivery Systems:

Multiple nanomedicines targeted for bone marrow inflammation, osteosarcoma, bone metastatic cancer, multiple myeloma, and osteoporosis have been used for research and treatment. Below is a partial list of FDA-approved bone-targeting drugs for your reference.

Table 1 FDA-approved Bone-targeting drugs

Our Featured Services:

Figure 2 The modification of the drug we can provide^[2]

• Design and Synthesis: CD Bioparticles can provide you with the most scientific and reliable bone targeting strategies, a variety of bone targeting vehicles and services including nano-based delivery systems such as lipids, liposome, polymeric and inorganic nanocarriers, micelles, microparticles and nanoaggregates for bone treatment.
• Drug Modifications: A range of ligand coating services are available from CD Bioparticles, including small molecules, proteins, peptides, antibodies, polymer and aptamers (Figure 2).
• Analysis and Characterization: Size, surface properties, encapsulation efficiency, lipophilicity, roughness, rigidity, etc.
• Testing in vitro and in vivo: Toxicity, drug efficacy, immunogenicity, metabolic level, drug aggregation, organ distribution, drug release ability, localization studies, etc.

References:
1. Patricia I: Scientists Identify Possible GD-Linked Bone Disease Therapeutic Target (gaucherdiseasenews.com) 2018.
2. Vargason AM, Anselmo AC, Mitragotri S: The evolution of commercial drug delivery technologies. Nat Biomed Eng. 2021, 5(9):951-967.