Early Cost-Effectiveness Analysis of Intra-articular Delivery of a PBAE-DEX Conjugate for Osteoarthritis in a UK...

Osteoarthritis affects the cartilage tissue lining the joint. Current management plans often require intra-articular injections to relieve symptoms. This approach is hindered by the difficulty in localising the drug released in the synovial fluid into the cartilage surrounding the affected joint. Drug delivery systems have been developed to support cartilage drug uptake, potentially reducing the number of injections required. We developed an approach to drug localisation that exploits the highly electrostatically charged nature of cartilage constituents through binding biologically active molecules to positively charged polymers, and demonstrated high efficacy and safety in ex vivo tests.

We wanted to demonstrate the potential value of cartilage drug localisation technology beyond a clinical perspective, through health economic considerations and cost-effectiveness analysis, in order for these technologies to reach patients. We also conducted threshold analyses to determine, for different effectiveness levels of reducing injections, at what price the treatment will be cost-effective.

We conducted an early health economic analysis of our technology, developing a cost-effectiveness model with a Markov structure. The analyses were conducted from an NHS perspective and the model was also used to estimate potential cost-effectiveness depending on target product profiles. The health states quality of life values were derived for a UK population through EQ-5D questionnaires collected and analysed in a Bayesian framework.

At the cost and effectiveness values set for the new treatment, it was cost-effective (increased costs of £16.28 and 0.001126 QALY per patient, resulting in an incremental cost-effectiveness ratios [ICER] of £14,459/QALY) but the results were highly uncertain (at a willingness-to-pay [WTP] of £20,000 and £30,000/QALY the probability of being cost-effective was 56.5% and 67.3%, respectively); while sensitivity analyses (one-way deterministic and probabilistic), within plausible ranges of model parameters, revealed that the efficacy of the technology in reducing intra-articular injections and its cost are the most influential parameters.

Clinical trials are needed to validate the in vivo drug delivery system efficacy, but our study suggests that the system is likely to be a cost-effective use of NHS resources, also improving healthcare providers capacity.