Osteoarthritis (OA) is the most common form of arthritis. There is no cure for it and the current treatments only manage symptomatic pain and inflammation. Among all the treatments available, non-steroidal anti-inflammatory drugs (NSAIDs) are the most widely prescribed. There are 2 types of NSAIDs – non-selective cyclooxygenase (COX) inhibitors and selective COX-2 inhibitors. Selective COX-2 inhibitors are preferred as they cause less side-effects compared to non-selective COX inhibitors. Only one COX-2 inhibitor (Celebrex®, Pfizer, CT, USA) has been approved by both FDA and EMA. This approval is despite the fact that Celebrex (having the celecoxib as active pharmaceutical ingredient) has a black box warning concerning possible side-effects for cardiovascular events and gastrointestinal bleeding following oral administration. Injecting the drug directly into the OA joint via intra articular (IA) injection could be an efficient way to reduce or eliminate these side effects. However, the free celecoxib (Cel) molecules are likely to be removed from knee joints within a few hours due to their low molecular weight, thus decreasing the local bioavailability and efficacy. The only way to increase the retention time of Cel is to load the drug in a biocompatible nanoparticle (NP) and inject the drug-loaded NP to the inflamed joint through IA injection.
This project is important because it will attempt to reduce the side-effects that are associated with the commonly used medicine for OA i.e. Cel. Moreover, it will increase the bioavailability of the drug which will decrease the overall treatment cost. The NP that was developed in this project could potentially be loaded with drugs used for other indications like cancer and could have similar benefits of increased bioavailability, more efficacy, low side-effects, and reduced treatment cost.
The main objective of this project was to develop a Cel-loaded biocompatible NP and demonstrate its application for IA drug delivery of Cel to treat OA.
The other objectives of the project were:
1. To enhance the knowledge of the researcher in terms of technical, transferable, and complementary skills.
2. To enhance the host supervisor capacity in delivering nanomedicine projects.
3. To disseminate, communicate and exploit the results of the project.
In summary, the biocompatible Cel-loaded human serum albumin (HSA) NPs were successfully synthesised and characterised. The NPs reduced markers associated with inflammation in an activated human monocytic cell line (THP-1) and in primary chondrocytes from the knee joints of OA patients.