Inpharma 1248 - 29 Jul 2000

Sildenafil cost effective versus notreatment

Sildenafil [‘Viagra’] is cost effective relative to notreatment, from both the third-party-payer and societalperspectives, according to the results of an independentUS-based modelling study.

The researchers, from Mercy Hospital of Pittsburghand the University of Pittsburgh, US, conclude that thecost utility of sildenafil compares favourably with thoseof commonly recommended medical interventions,such as renal dialysis, lipid-lowering agents andcoronary artery bypass graft surgery. ‘Therefore, it seemsthat insurance companies that limit or deny coverage forsildenafil have not based their decisions on cost-effectivecalculations’, they comment.

$US11 000 per QALY gainedUsing a Markov decision model, the researchers

estimated that treatment with sildenafil would generatean additional 0.35 quality-adjusted life-years (QALYs),compared with no treatment, in a hypothetical cohort of60-year-old men with erectile dysfunction. From theperspective of a third-party payer, this benefit wouldhave a direct cost of $US3950, where this cost includedcosts related to acquiring sildenafil and treating itsadverse effects.* From the societal perspective,sildenafil treatment was associated with a cost of$US3970, where this cost included direct costs as wellas lost wages due to time spent obtaining care. Usingthese costs, the researchers estimated that each QALYgained with sildenafil, compared with no treatment,would cost $US11 230 from the third-party-payerperspective or $US11 290 from the societalperspective.**

Sensitivity analysis revealed that the results weresensitive to changes in the effectiveness of sildenafil, therates of morbidity and mortality associated withsildenafil, the rate of spontaneous remission of erectiledysfunction, the rate of erectile dysfunction aftersuccessful therapy, the disutility of erectile dysfunction,and the cost of sildenafil. However, the researchersclaim that, on the whole, ‘assumptions biased the base-case analysis against sildenafil use’.* It was assumed that patients took 6 sildenafil tablets per month andthat adverse effects could require hospitalisation and long-termtreatment for cardiac conditions.** Costs (1998 values) and benefits were discounted at 3% per annum.

Smith KJ, et al. The cost-effectiveness of sildenafil. Annals of Internal Medicine132: 933-937, 20 Jun 2000 800836815

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Inpharma 29 Jul 2000 No. 12481173-8324/10/1248-0001/$14.95 Adis © 2010 Springer International Publishing AG. All rights reserved