Impact of abciximab versus tirofiban on hospital length of stay for PCI patients

Tirofiban for the treatment of ischaemic stroke

Tirofiban is one of three glycoprotein IIb/IIIa receptor antagonists approved by the US FDA, beside abciximab and eptifibatide. The approval of tirofiban covers conservative treatment of myocardial infarction and unstable angina, as well as percutaneous coronary intervention, for which treatment with tirofiban is recommended in moderate-to-high-risk patients. The efficacy of glycoprotein IIb/IIIa antagonists in myocardial infarction indicated that these agents may also be helpful in the treatment of acute ischaemic stroke. Although experimental data are lacking, observational studies are promising. In recent years, increasing effort in studying glycoprotein IIb/IIIa antagonists has been made, mostly for treatment with abciximab. However, there is one Phase II trial that investigated treatment with tirofiban.

Choice of GPIIb/IIIa antagonist in percutaneous coronary intervention: how should economic criteria be factored in?

OBJECTIVE

Three GPIIb/IIIa antagonists are available in the market. In France, as in many countries, their acquisition costs strongly differ. The objective of this study was to analyze how economic criteria-beyond the acquisition cost-should be factored in, when choosing a GPIIb/IIIa antagonist.

METHOD

Both clinical and economic papers on the use of GPIIb/IIIa antagonists in percutaneous coronary interventions published in peer-review journals from 1994 to 2002 were reviewed and analyzed.

RESULTS

Cost differentials between products strongly vary from one 'cost concept' to another, i.e., acquisition cost, administration cost, hospital cost, net treatment cost. The comparison of efficacy is even more complicated, as most of the time only indirect comparisons are available, based on different clinical studies, with different durations and definitions of outcomes. Finally, cost-effectiveness ratios range from US dollar 10,695 per avoided event for eptifibatide (IMPACT II study) to US dollar 74,047 for tirofiban (RESTORE study).

CONCLUSION

The concept of cost, inevitably entering into the choice of a medicinal strategy, must be used with caution. The amplitude of the difference between products, and the product favored by the difference, vary according to the cost concept retained.

Outcomes with changes in prescribing of glycoprotein IIb/IIIa inhibitors in PCI

BACKGROUND

Glycoprotein IIb/IIIa receptor antagonists have been shown to have an impact on the outcomes of death/myocardial infarction (MI) in patients undergoing percutaneous coronary intervention. At our institution, tirofiban has largely replaced abciximab in an attempt to decrease costs.

OBJECTIVE

To assess the impact of this change on patient outcomes in the absence of head-to-head trials.

METHODS

Medical records were reviewed and telephone follow-ups were conducted on patients receiving tirofiban (n = 83) at our facility between February and November 1999. Death/MI at 30 days and 6 months after infusion were recorded. Safety and length of stay (LOS) were also assessed. These data were compared using chi2 analysis with results obtained from a previous review of abciximab use (n = 83) collected between May 1997 and November 1998.

RESULTS

There was no difference in the baseline incidence of (1) cardiovascular risk factors, (2) prior revascularization, (3) prior MI, (4) the number of vessels with atherosclerotic disease assessed by angiography, and (5) the number of vessels receiving procedures. Death/MI trended to be worse with tirofiban versus abciximab at our institution at 30 days (4.8% abciximab vs. 12% tirofiban; p = 0.163) and 6 months (6% abciximab vs. 18.1% tirofiban; p = 0.032). Bleeding and median LOS (3 d abciximab vs. 3 d tirofiban) were not different. Despite an increase in pharmacy cost, the use of abciximab provided these outcomes without an increase in total hospital cost.

CONCLUSIONS

The perceived economically driven change in medication selection from abciximab to tirofiban may not have been appropriate based on the negative trends seen in this review. To maintain optimal patient outcomes, this change should be reevaluated.

Abciximab: an updated review of its therapeutic use in patients with ischaemic heart disease undergoing percutaneous coronary revascularisation

Abciximab (Reopro) is an antibody fragment that dose-dependently inhibits platelet aggregation and leucocyte adhesion by binding to the glycoprotein (GP) IIb/IIIa, vitronectin and Mac-1 receptors. Abciximab (0.25 mg/kg bolus plus infusion of 0.125 micro g/kg/min for 12 hours) showed greater efficacy than tirofiban in reducing the 30-day composite endpoint of death, nonfatal myocardial infarction (MI) or urgent target-vessel revascularisation in the randomised, double-blind TARGET study in patients scheduled for stent placement. In addition, the beneficial effects of treatment with abciximab previously observed in the randomised, multicentre, placebo-controlled EPILOG and EPISTENT studies have been maintained to 1 year, with a significantly reduced incidence of ischaemic complications relative to placebo consistently observed across a range of subgroups including age, sex, bodyweight and indication for revascularisation. The incidence of the composite endpoint was reduced in patients presenting with acute MI of <48 hours' duration in comparison with either fibrinolytic therapy or stenting alone in the randomised STOPAMI and ADMIRAL trials, primarily because of a reduced requirement for urgent repeat revascularisation and reduced incidence of mortality. In the randomised, nonblind, multicentre CADILLAC trial in patients with acute myocardial infarction (MI), stenting alone was superior to percutaneous transluminal coronary angioplasty (PTCA) and stenting alone was not inferior to PTCA plus abciximab. Recent large randomised, multicentre studies (ASSENT-3 and GUSTO-V) have shown higher efficacy (on various ischaemic endpoints) of abciximab in combination with either a reduced dose of tenecteplase or reteplase compared with the fibrinolytic drug alone. TIMI grade 3 flow rates at 60 and 90 minutes in the TIMI-14 and SPEED trials were higher in patients who received abciximab in combination with either alteplase or reteplase than abciximab alone and were similar to that seen with the full-dose fibrinolytic alone. In the randomised, multicentre GUSTO IV-ACS study, no significant differences in any of the ischaemic endpoints at either 7 or 30 days in patients with acute coronary syndromes who were not scheduled to undergo early revascularisation (within 12 hours of end of infusion) were apparent between those who received abciximab (bolus and either 24- or 48-hour infusion) and those who received placebo in addition to aspirin and heparin. The most common adverse events associated with the use of abciximab are bleeding complications and thrombocytopenia, although the risk of major bleeding can be limited through adhering to current administration protocols. Treatment costs are generally higher in both stent plus abciximab and angioplasty plus abciximab groups than stent plus placebo, primarily because of the acquisition cost of abciximab. Abciximab appeared most cost beneficial in high-risk patients undergoing elective percutaneous coronary revascularisation; among lower risk patients, abciximab therapy has been associated with higher total in-hospital and 6-month medical costs than eptifibatide.

CONCLUSION

The GP IIb/IIIa receptor antagonist abciximab, when used with aspirin and heparin, has demonstrated efficacy in reducing the short- and long-term risk of ischaemic complications in patients with ischaemic heart disease undergoing percutaneous coronary intervention, when used with aspirin and heparin. High-risk patients (including those with diabetes mellitus) derive particular benefits from abciximab treatment. Abciximab remains an important therapeutic option for the prevention of complications in patients with ischaemic heart disease.

A comparison of total hospital costs for percutaneous coronary intervention patients receiving abciximab versus tirofiban

The purpose of this study was to examine the total hospital costs associated with the receipt of abciximab versus tirofiban for percutaneous coronary intervention (PCI) patients. Hospital billing data for patients with a primary procedure of PCI was examined for the period of July 1998 to June 1999 from HCIA-Sach's Clinical Pathways Database. Data were analyzed for all patient discharges whose records indicated use of abciximab or tirofiban with a PCI. Results are reported for 3,967 patients. Multivariate analysis was used to control for a wide range of factors (GP IIb/IIIa selection, patient demographics, stent use, insurance type, health conditions, admission information, and hospital characteristics) that may influence the cost of hospitalization. A two-stage sample selection model was used to estimate total costs. The first stage of the analysis utilizes a probit regression to determine the factors associated with the likelihood of receiving abciximab versus tirofiban. The second stage of the analysis examines the factors associated with total hospital costs, while controlling for unobserved factors that may be correlated with the patient's likelihood of receiving abciximab. The mean unadjusted cost per hospitalization, including drug costs, was $10,762 (abciximab $10,813 and tirofiban $10,567). After controlling for high-risk indications and selection bias with the two-stage sample selection model, results indicate there was no significant difference in costs associated with the receipt of abciximab versus tirofiban. However, the results also indicate that the two-stage sample selection model may not be needed (lambda was not statistically significant) hence, the cost equation was reestimated using ordinary least-squares methodology (OLS). In the OLS analysis, receipt of abciximab versus tirofiban was associated with a significant reduction in costs ($470 reduction; P = 0.05). This study uses real-world data to examine the total hospital costs for PCI patients who receive abciximab versus tirofiban. Results of the two-stage sample selection model indicate there is no difference in total hospital costs (including drug costs) between abciximab- and tirofiban-treated patients. If the results of the OLS model are considered, a slight decrease in total hospital costs is observed in abciximab recipients. Cost-containment strategies that focus on component costs may not lead to intended overall cost savings.