Summary
Using the method of willingness to pay (WTP). this study assesses the value of a new antidepressant, moclobemide. relative to that of tricyclic antidepressants (TCAs). which have equivalent efficacy but less favourable adverse effect profiles. From a published meta-analysis of controlled clinical trials. we identified 7 adverse effects. the risk of which differed significantly between moclobemide and TCAs. We obtained risk reduction data and descriptions of adverse effects from interviews with 95 individuals who had mild to moderate depression and who had been taking one or more TCAs in the previous year. Using a visual analogue scale, respondents ranked and rated each adverse effect. Participants were then asked (using the scenario of additional out-of-pocket drug payment) to quantify the maximum amount that the y would pay for a new drug that reduced each adverse effect by the specified probability.
Blurred vision and tremor were ranked and rated as the most bothersome adverse effects. with dry mouth being the least bothersome. On average. respondents were willing to pay an additional $Can22 per month [95% confidence interval (CI) 16-28] to reduce the risk of blurred vision from 10 to 5%. The lowest WTP value was for reducing the risk of dry mouth from 40 to 15%, at $Canl l per month (95%CI 8-l5). Although not measured directly, we derived 2 estimates of WTP for multiple (i.e. all 7) risk reductions. We obtained upper and lower WTP limits of $Can118 and $Can36 per month, respectively, depending upon aggregation assumptions, Compared with the TCAs amitriptyline and imipramine. the net cost of moclobemide is greater, but the overall net benefit (WTP minus cost) is ambiguous given uncertainty about WTP aggregation over adverse effects. However. compared with the TCAs desipramine and clomipramine, the net benefit of moclobemide is unambiguously positive.
We conclude that the WTP approach is a potentially valuable tool that requires more development for use in healthcare economic evaluation.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Elixhauser A, Luce BR, Taylor WR, et al. Health care CBA/CEA: an update in the growth and composition of the literature. Med Care 1993; 31: JS1–11
Commonwealth of Australia. Guidelines for the pharmaceutical industry on preparation of submissions to the Pharmaceutical Benefits Advisory Committee: including submissions involving economic analyses. Canberra: Department of Health, Housing and Community Services, 1990
Detsky A. Guidelines for preparation of economic analysis of pharmaceutical products: a draft document for Ontario and Canada. PharmacoEconomics 1993; 3: 354–61
Adams ME, McCall NT, Gray DT, et al. Economic analysis in randomized control trials. Med Care 1992; 30: 232–43
Phelps CE, Mushlin AI. On the (near) equivalence of cost-effectiveness and cost-benefit analyses. Int J Technol Assess Health Care 1991; 7: 12–21
Doubilet P, Weinstein MC, McNeil BJ. Use and misuse of the term ‘cost-effective’ in medicine. N Engl J Med 1986; 314: 253–5
Mason J, Drummond M, Torrance G. Some guidelines on the use of cost-effectiveness league tables. BMJ 1993; 306: 570–2
Sugden R, Williams AH. The principles of practical cost-benefit analysis. Oxford: Oxford University Press, 1979
Mishan EJ. Evaluation of life and limb: a theoretical approach. J Polit Econ 1971; 79: 687–706
Johannesson M, Jonsson B. Economic evaluation in health care: is there a role for cost-benefit analysis? Health Policy 1991; 17: 1–23
Thompson MS. Willingness to pay and accept risks to cure chronic disease. Am J Publ Health 1986; 76: 392–6
Berwick DM, Weinstein MC. What do patients value? Willingness to pay for ultrasound in normal pregnancy. Med Care 1985; 23: 881–93
Johannesson M, Jonsson B. Willingness to pay for antihypertensive theraphy–results of a Swedish pilot study. J Health Econ 1991; 10: 461–74
Appel LJ, Steinberg EP, Powe NR, et al. Risk reduction from low osmolality contrast media. What do patients think it is worth? Med Care 1990; 28: 324–34
Cosacchia M, Moll E. Moclobemide (RO 11-1163) versus imipramine in the treatment of depression [abstract]. Acta Psychiatr Scand 1990; Suppl. 36: 43
Ucho Udable R, Marquez CA, Trobolli CA, et al. Double-blind comparison of moclobemide, imipramine and placebo in depressive patients. Acta Psychiatr Scand 1990; Suppl. 360: 54–6
Versiani M, Nardi AE, Mundim FD, et al. Moclobemide, imipramine and placebo in the treatment of major depression. Acta Psychiatr Scand 1990; Suppl. 360: 57–8
Biziere K, Berger M. Efficacy of a reversible monoamine oxidase-A inhibitor versus imipramine in subgroups of depressed patients. Acta Psychiatr Scand 1990; Suppl. 360: 59–60
Versiani M, Nardi AE, Mundim FD, et al. Tolerability of moclobemide, a new reversible inhibitor of monoamine oxidase-A, compared with other antidepressants and placebo. Acta Psychiatr Scand 1990b: Suppl. 360: 24–8
Diagnostic and Statistical Manual of Mental Disorders. 3rd rev. ed. (DSM-III-R). Washington, DC: America n Psychiatric Association, 1987
Ontario Drug Benefit Formulary. Ottawa: Ontario Ministry of Health, 1992
Gafni A. Using willingness-to-pay as a measure of benefits: what is the relevant question to ask in the context of public decision making? Med Care 1991; 29: 1246–52
Neumann PJ, Johannesson M. The willingness to pay for in vitro fertilization: a pilot study using contingent valuation. Med Care 1994; 32: 686–99
O’Brien A, Viramontes JL. Willingness-to-pay a valid and reliable measure of health state preference? Med Decis Making 1994; 14: 289–97
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
O’Brien, B.J., Novosel, S., Torrance, G. et al. Assessing the Economic Value of a New Antidepressant. Pharmacoeconomics 8, 34–45 (1995). https://doi.org/10.2165/00019053-199508010-00006
Published:
Issue Date:
DOI: https://doi.org/10.2165/00019053-199508010-00006