Would a Large tPA Trial for Those 4.5 to 6.0 Hours from Stroke Onset Be Good Value for Information?

• Published in: Value in health 2017-07, Vol.20 (7), p.894-901
• Main Authors: Soeteman, Djøra I., PhD, Menzies, Nicolas A., PhD, Pandya, Ankur, PhD
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Brain Ischemia - drug therapy; Brain Ischemia - economics; Cost-Benefit Analysis; cost-effectiveness/economic; decision analysis; Female; Fibrinolytic Agents - administration & dosage; Fibrinolytic Agents - economics; Fibrinolytic Agents - therapeutic use; Humans; Internal Medicine; Male; Markov Chains; Middle Aged; Quality-Adjusted Life Years; Randomized Controlled Trials as Topic; stroke; Stroke - drug therapy; Stroke - economics; Time Factors; Tissue Plasminogen Activator - administration & dosage; Tissue Plasminogen Activator - economics; Tissue Plasminogen Activator - therapeutic use; Treatment Outcome; value of information
• ISSN: 1098-3015; 1524-4733
• DOI: 10.1016/j.jval.2017.03.004

Abstract Objectives To quantify the potential value of new research in patients treated with thrombolytic treatment (tissue-type plasminogen activator [tPA]) in the 4.5- to 6.0-hour time window after stroke onset and to determine the optimal size of a future trial using value of information analysis. Methods Expected value of partial perfect and sample information (EVPPI and EVSI) analyses were conducted using a probabilistic Markov model. Data for modified Rankin Scale (mRS) distributions in patients 4.5 to 6.0 hours since stroke onset for tPA (n = 576) and placebo (n = 543) were obtained from pooled randomized controlled trials. EVSI was quantified with net monetary benefit (assuming willingness to pay for health as $100,000/QALY). We calculated discounted population-level EVSI by multiplying per-person EVSI by the annual number of eligible patients with stroke in the United States and assuming a 10-year time frame of treatment use. Study costs were based on administrative costs and the costs of tPA. Results The base-case lifetime cost-effectiveness analysis showed that tPA was dominated by placebo in this patient group. EVPPI for mRS distributions was $1003 per person. On the basis of EVSI, the optimal sample size of a new trial collecting data on tPA efficacy in these patients would be 5600 across study arms with expected population-level societal returns (EVSI minus study costs) of $68.7 million. Conclusions Expanding research attention to the 4.5- to 6.0-hour time window for tPA treatment of patients with acute ischemic stroke is justified because the expected returns are substantial. Even a relatively large trial in which more information on treatment efficacy on the basis of mRS scores is collected would represent good value for information.