Economic evaluation of the randomised, double

Treating chronic, uncontrolled, cancer pain with subcutaneous ketamine in patients unresponsive to opioids and co-analgesics remains controversial, especially in light of recent evidence demonstrating ketamine does not have net clinical benefit in this setting. To evaluate the cost-effectiveness of subcutaneous ketamine versus placebo in this patient population. A within-trial cost-effectiveness analysis of the Australian Palliative Care Clinical Studies Collaborative’s randomised, double-blind, placebo-controlled trial of ketamine was conducted from a healthcare provider perspective. Mean costs and outcomes were estimated from participant-level data over 5？days including positive response, health-related quality of life (HrQOL) measured with the Functional Assessment of Chronic Illness Therapy–Palliative Care (FACIT-Pal), ketamine costs, medication usage and in-patient stays. There was no statistically significant difference in responder rates, but higher toxicity and worse HrQOL for ketamine participants (mean change ？3.10 (standard error (SE) 1.76), ketamine n？=？93; 4.53 (SE 1.38), placebo n？=？92). Estimated total mean costs were AU$706 higher per ketamine participant (AU$6608) compared with placebo (AU$5902), attributable to the cost of higher in-patient costs as well as costs of ketamine administration. The results were robust to sensitivity analyses accounting for different medication use costing methods and removal of cost outliers. The findings suggest subcutaneous ketamine in conjunction with opioids and standard adjuvant therapy is neither an effective nor cost-effective treatment for refractory pain in advanced cancer patients