Are There Different Evidence Thresholds for Genomic Versus Clinical Precision Medicine? A Value of Information-Based Framework Applied to Antiplatelet Drug Therapy

BACKGROUND

The threshold of sufficient evidence for adoption of clinically- and genomically-guided precision medicine (PM) has been unclear.

OBJECTIVE

To evaluate evidence thresholds for clinically guided PM versus genomically guided PM.

METHODS

We develop an "evidence threshold criterion" (ETC), which is the time-weighted difference between expected value of perfect information and incremental net health benefit minus the cost of research, and use it as a measure of evidence threshold that is proportional to the upper bound of disutility to a risk-averse decision maker for adopting a new intervention under decision uncertainty. A larger (more negative) ETC value indicates that only decision makers with low risk aversion would adopt new intervention. We evaluated the ETC plus cost of research (ETCc), assuming the same cost of research for both interventions, over time for a pharmacogenomic (PGx) testing intervention and avoidance of a drug-drug interaction (aDDI) intervention for acute coronary syndrome patients indicated for antiplatelet therapy. We then examined how the ETC may explain incongruous decision making across different national decision-making bodies.

RESULTS

The ETCc for PGx increased over time, whereas the ETCc for aDDI decreased to a negative value over time, indicating that decision makers with even low risk aversion will have doubts in adopting PGx, whereas decision makers who are highly risk-averse will continue to have doubts about adopting aDDI. National recommendation bodies appear to be consistent over time within their own decision making, but had different levels of risk aversion.

CONCLUSION

The ETC may be a useful metric for assessing policy makers' risk preferences and, in particular, understanding differences in policy recommendations for genomic versus clinical PM.

Prasugrel vs. clopidogrel in contemporary Western European patients with acute coronary syndromes receiving drug-eluting stents: Comparative cost-effectiveness analysis from the BASKET-PROVE cohorts

BACKGROUND

Clinical and cost-effectiveness of prasugrel vs. clopidogrel in acute coronary syndrome (ACS) was only evaluated using TRITON-TIMI 38 event rates. A comparative analysis of both drugs in contemporary European ACS patients is lacking.

METHODS

To address this issue, cardiac and bleeding events of 2 "sister" multicenter stent trials, BASKET-PROVE (BP) I with clopidogrel and BPII with prasugrel (for 12months each) were used in a hybrid analysis. Medication costs were 2015 sales prices, event costs modelled for Denmark (DNK), Germany (GER) and Switzerland (SUI) and quality adjusted life years (QALY) by EQ-5D-3L questionnaire.

RESULTS

In BPI and II, 1012 and 985 ACS-patients received drug eluting stents, respectively, followed-up for 2years. Compared to clopidogrel, prasugrel-treated patients had no more major cardiac events (5.2% vs. 6.4%, p=0.422) nor cardiac deaths (1.6% vs. 1.0%, p=0.255), but more major bleedings (4.0% vs. 1.7%, p<0.001) and altogether no difference in QALYs (-0.027 (95%CI: -0.064/0.011)). Prasugrel caused higher total expenditures per patient: 1116.3 (DNK), 1063.5 (GER) and 880.8 (SUI) EURO, respectively. Accordingly, incremental cost-effectiveness was negative for prasugrel vs. clopidogrel with ratios of -45,907 (DNK), -39,909 (GER) and -33,435 (SUI) EURO/QALY gained, making clopidogrel an economically dominant strategy, even after accounting for the non-randomized comparison.

CONCLUSION

Findings of this contemporary European ACS-cohort showed markedly lower cardiac event rates than TRITON-TIMI 38 and no significant difference in 2-year QALYs between prasugrel and clopidogrel-treated patients. At current drug prices, clopidogrel use resulted in an economically dominant treatment strategy in Western European patients.

CYP2C19 LOF and GOF-Guided Antiplatelet Therapy in Patients with Acute Coronary Syndrome: A Cost-Effectiveness Analysis

PURPOSE

This study aimed to examine the cost-effectiveness of CYP2C19 loss-of-function and gain-of-function allele guided (LOF/GOF-guided) antiplatelet therapy in patients with acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI).

METHODS

A life-long decision-analytic model was designed to simulate outcomes of three strategies: universal clopidogrel (75 mg daily), universal alternative P2Y₁₂ inhibitor (prasugrel 10 mg daily or ticagrelor 90 mg twice daily), and LOF/GOF-guided therapy (LOF/GOF allele carriers receiving alternative P2Y₁₂ inhibitor, wild-type patients receiving clopidogrel). Model outcomes included clinical event rates, quality-adjusted life-years (QALYs) gained and direct medical costs from perspective of US healthcare provider.

RESULTS

Base-case analysis found nonfatal myocardial infarction (5.62%) and stent thrombosis (1.2%) to be the lowest in universal alternative P2Y₁₂ inhibitor arm, whereas nonfatal stroke (0.72%), cardiovascular death (2.42%), and major bleeding (2.73%) were lowest in LOF/GOF-guided group. LOF/GOF-guided arm gained the highest QALYs (7.5301 QALYs) at lowest life-long cost (USD 76,450). One-way sensitivity analysis showed base-case results were subject to the hazard ratio of cardiovascular death in carriers versus non-carriers of LOF allele and hazard ratio of cardiovascular death in non-carriers of LOF allele versus general patients. In probabilistic sensitivity analysis of 10,000 Monte Carlo simulations, LOF/GOF-guided therapy, universal alternative P2Y₁₂ inhibitor, and universal clopidogrel were the preferred strategy (willingness-to-pay threshold = 50,000 USD/QALY) in 99.07%, 0.04%, and 0.89% of time, respectively.

CONCLUSIONS

Using both CYP2C19 GOF and LOF alleles to select antiplatelet therapy appears to be the preferred antiplatelet strategy over universal clopidogrel and universal alternative P2Y₁₂ inhibitor therapy for ACS patients with PCI.

Comparison of healthcare resource utilization and costs in patients hospitalized for acute coronary syndrome managed with percutaneous coronary intervention and receiving prasugrel or ticagrelor

OBJECTIVE

To compare healthcare resource utilization (HCRU) and healthcare costs in patients with acute coronary syndrome (ACS) managed with percutaneous coronary intervention (PCI) and treated with prasugrel or ticagrelor.

METHODS

Hospital charge master data were used to identify ACS-PCI patients aged ≥ 18 years with ≥ 1 in-hospital claim for prasugrel or ticagrelor between August 1, 2011-April 30, 2013. Treatment groups were propensity matched for baseline and index hospitalization characteristics. HCRU and costs were assessed through 90-days post-discharge. Costs were determined based on hospital-specific cost-to-charge ratios and adjusted to 2013 US dollars.

RESULTS

Before matching, ticagrelor patients were older, more-often female, and had increased cardiovascular (CV) and bleeding risks compared with prasugrel patients. Propensity-matched length of index hospital stay (4.7 vs 4.9 days, p = 0.23) and risk for all-cause [30-day: relative risk (RR) = 0.86; 95% CI = 0.73-1.0; 90-day: RR = 0.90; 95% CI = 0.80-1.0, and CV-related (30-day: RR = 0.77; 95% CI = 0.59-1.0; 90-day: RR = 0.89; 95% CI = 0.73-1.1) re-hospitalizations did not significantly differ between prasugrel and ticagrelor, respectively. Compared to ticagrelor, the propensity-matched risk of re-hospitalization for myocardial infarction (MI) (30-day: RR = 0.39; 95% CI = 0.21-0.75; 90-day: RR = 0.53; 95% CI = 0.34-0.81) and an outpatient medical encounter for dyspnea (30-day: RR = 0.49; 95% CI = 0.33-0.74; 90-day: RR = 0.60; 95% CI = 0.46-0.80) were significantly lower for prasugrel patients, with no significant differences in bleeding encounters between groups (30-day: RR =  0.87; 95% CI = 0.54-1.40; 90-day: RR = 1.0; 95% CI = 0.71-1.50). Matched total healthcare costs were not significantly different between groups during the index hospitalization ($36,011 vs $37,247, p = 0.21), 30-days post-discharge ($2007 vs $2522, p = 0.48), 90-days post-discharge ($4564 vs $5242, p = 0.49), and aggregate of the index hospitalization through 90-day follow-up ($40,576 vs $42,494, p = 0.09) timeframes.

CONCLUSIONS

Re-hospitalization for MI and outpatient encounters for dyspnea were lower in prasugrel treated than in ticagrelor treated ACS-PCI patients up to 90-days post-index hospitalization discharge, with no difference in bleeding encounters or healthcare costs between the two populations. This data supports the utility of prasugrel in routine clinical practice. These findings should be considered within limitations of observational research.

Economic outcomes with prasugrel versus clopidogrel in acute coronary syndrome patients: observations from prasugrel users and matched clopidogrel users

OBJECTIVE

To compare healthcare costs between clopidogrel and prasugrel over 30-day and 365-day periods after discharge from the hospital or emergency room (ER) in patients treated with prasugrel who were hospitalized or had an ER visit for an acute coronary syndrome (ACS) event.

METHODS

This retrospective observational study was based on claims from January 2009-July 2012 in the Truven Health Analytics MarketScan database. Clopidogrel patients were propensity-score matched 1:1 to prasugrel-treated patients. Lin's frequentist cost history method for censored data and Bayesian zero-inflated gamma regression models were used to analyze healthcare costs.

RESULTS

The clopidogrel/prasugrel matched-cohort included 10,963 well-matched pairs of patients. Lin's frequentist analysis showed that outpatient visit costs were significantly lower for clopidogrel than prasugrel after 30 days of follow-up. At 30 days, Bayesian data analysis showed strong evidence that clopidogrel was superior to prasugrel for all-cause and ACS-related hospitalization costs and showed very strong evidence that clopidogrel was superior to prasugrel for all-cause and ACS-related outpatient visit costs. At 365 days, Bayesian data analysis showed strong evidence that clopidogrel was superior to prasugrel for all-cause outpatient visit costs and very strong evidence that clopidogrel was superior to prasugrel for ACS-related outpatient visit costs. Point estimates of the all-cause and ACS-related ER visit costs at 30 days and 365 days were similar, but statistical results were inconclusive because of the large variability in this outcome variable.

CONCLUSION

Based on retrospective observational data in a real-world setting, all-cause and ACS-related hospitalization and outpatient visit costs were lower for clopidogrel than prasugrel over 30 days after discharge from a hospitalization or ER visit associated with ACS in patients treated with prasugrel. At 365 days the difference in all-cause and ACS-related outpatient costs remained, but there was little evidence of a difference in either all-cause or ACS-related hospitalization costs.