RESUMEN
Almost all pharmaceutical products are approved on the basis of their effect in patients representing the "average" of the population studied in registrational trials, with most drug labels allowing, at most, for empirical dose reduction in the case of toxicity. In this perspective article we explore some of the evidence that supports the use of personalised dosing in cancer treatment and show how we have been able to build on existing models linking dose, exposure and toxicity to demonstrate how dose optimisation, including increasing the dose, has the potential to significantly improve efficacy outcomes. We also explore, through the lens of our own experience of developing a personalised dosing platform, some of the hurdles that stand in the way of implementing a personalised approach to dosing in real world settings. In particular, our experience is illustrated by the application of a dosing platform for docetaxel treatment in prostate cancer.
RESUMEN
OBJECTIVES: To evaluate the cost effectiveness of onabotulinumtoxinA (BOTOX(®), 200 units [200 U]) for the management of urinary incontinence (UI) in adults with neurogenic detrusor overactivity (NDO) due to subcervical spinal cord injury or multiple sclerosis that is not adequately managed with anticholinergic drugs (ACHDs). PERSPECTIVE: UK National Health Service (NHS) perspective. METHODS: A Markov state-transition model was developed, which compared onabotulinumtoxinA + best supportive care (BSC) with BSC alone (comprising behavioural therapy and pads, alone or in combination with clean intermittent catheterization and possibly with ACHDs). Non-responders were eligible for invasive procedures. Health states were defined according to the reduction in UI episodes. Efficacy data and estimates of resource utilization were pooled from 468 patients on onabotulinumtoxinA in two phase III clinical trials. Drug costs (2013) and administration costs (NHS Reference Costs 2011-2012) were obtained from published sources. The time horizon of the model was 5 years, and costs and benefits were discounted at 3.5%. Scenario, one-way and probabilistic sensitivity analyses (PSAs) were conducted to explore uncertainties around the assumptions. RESULTS: In the base case, treatment with onabotulinumtoxinA + BSC over 5 years was associated with an increase in costs of £1,689 and an increase in quality-adjusted life-years (QALYs) of 0.4, compared with BSC alone, resulting in an incremental cost-effectiveness ratio of £3,850 per QALY gained. Sensitivity analyses showed that utility values had the greatest influence on model results. PSA suggests that onabotulinumtoxinA + BSC had a 100 % probability of being cost effective at a willingness to pay of <£20,000. CONCLUSION: For adult patients with NDO who are not adequately managed with ACHDs, onabotulinumtoxinA + BSC appears to be a cost-effective use of resources in the UK NHS.