US-Based Drug Cost Parameter Estimation for Economic Evaluations

Cost Effectiveness of Dapagliflozin for Heart Failure Across the Spectrum of Ejection Fraction: An Economic Evaluation Based on Pooled, Individual Participant Data From the DELIVER and DAPA-HF Trials

BACKGROUND

The sodium glucose cotransporter-2 inhibitors are guideline-recommended to treat heart failure across the spectrum of left ventricular ejection fraction; however, economic evaluations of adding sodium glucose cotransporter-2 inhibitors to standard of care in chronic heart failure across a broad left ventricular ejection fraction range are lacking.

METHODS AND RESULTS

We conducted a US-based cost-effectiveness analysis of dapagliflozin added to standard of care in a chronic heart failure population using pooled, participant data from the DAPA-HF (Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure) and DELIVER (Dapagliflozin Evaluation to Improve the Lives of Patients With Preserved Ejection Fraction Heart Failure) trials. The 3-state Markov model used estimates of transitional probabilities, effectiveness of dapagliflozin, and utilities from the pooled trials. Costs estimates were obtained from published sources, including published rebates in dapagliflozin cost. Adding dapagliflozin to standard of care was estimated to produce an additional 0.53 quality-adjusted life years (QALYs) compared with standard of care alone. Incremental cost effectiveness ratios were $85 554/QALY when using the publicly reported full (undiscounted) Medicare cost ($515/month) and $40 081/QALY, at a published nearly 50% rebate ($263/month). The addition of dapagliflozin to standard of care would be of at least intermediate value (<$150 000/QALY) at a cost of <$872.58/month, of high value (<$50 000/QALY) at <$317.66/month, and cost saving at <$40.25/month. Dapagliflozin was of at least intermediate value in 92% of simulations when using the full (undiscounted) Medicare list cost in probabilistic sensitivity analyses. Cost effectiveness was most sensitive to the dapagliflozin cost and the effect on cardiovascular death.

CONCLUSIONS

The addition of dapagliflozin to standard of care in patients with heart failure across the spectrum of ejection fraction was at least of intermediate value at the undiscounted Medicare cost and may be potentially of higher value on the basis of the level of discount, rebates, and price negotiations offered.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01035255 & NCT01920711.

Health care resource utilization and costs in patients with painful diabetic neuropathy treated with 10 kHz spinal cord stimulation therapy

BACKGROUND: Diabetic peripheral neuropathy, a common comorbidity of diabetes, is a neurodegenerative disorder that targets sensory, autonomic, and motor nerves frequently associated with painful diabetic neuropathy (PDN). PDN carries an economic burden as the result of reduced work and productivity. A recent multicenter randomized controlled trial, SENZA-PDN (NCT03228420), assessed the impact of high-frequency (10 kHz) spinal cord stimulation (SCS) on pain relief. The effects of high-frequency SCS on health care resource utilization and medical costs are not known. OBJECTIVE: To evaluate the effect of high-frequency (10 kHz) SCS on health care resource utilization (HRU) and medical costs in patients with PDN using data from the SENZA-PDN trial. METHODS: Participants with PDN were randomly assigned 1:1 to receive either 10 kHz SCS plus conventional medical management (CMM) (SCS treatment group) or CMM alone (CMM treatment group). Patient outcomes and HRU up to the 6-month follow-up are reported here. Costs (2020 USD) for each service was estimated based on publicly available Medicare fee schedules, Medicare claims data, and literature. HRU metrics of inpatient and outpatient contacts and costs are reported as means and SDs. Univariate and bivariate analyses were used to compare SCS and CMM treatment groups at 6 months. RESULTS: At 6-month follow up, the SCS arm experienced approximately half the mean rate of hospitalizations per patient compared with the CMM treatment group (0.08 vs 0.15; P = 0.066). The CMM treatment group's total health care costs per patient were approximately 51% higher compared with the SCS treatment group (equivalent to mean annual cost per patient of $9,532 vs $6,300). CONCLUSIONS: Our analysis of the SENZA-PDN trial indicates that the addition of 10 kHz SCS therapy results in lower rates of hospitalization and consequently lower health care costs among patients with PDN compared with those receiving conventional management alone.

Estimating Drug Costs: How do Manufacturer Net Prices Compare with Other Common US Price References?

BACKGROUND

Drug costs are frequently estimated in economic analyses using wholesale acquisition cost (WAC), but what is the best approach to develop these estimates? Pharmaceutical manufacturers recently released transparency reports disclosing net price increases after accounting for rebates and other discounts.

OBJECTIVE

Our objective was to determine whether manufacturer net prices (MNPs) could approximate the discounted prices observed by the U.S. Department of Veterans Affairs (VA).

METHODS

We compared the annual, average price discounts voluntarily reported by three pharmaceutical manufacturers with the VA price for specific products from each company. The top 10 drugs by total sales reported from company tax filings for 2016 were included. The discount observed by the VA was determined from each drug's list price, reported as WAC, in 2016. Descriptive statistics were calculated for the VA discount observed and a weighted price index was calculated using the lowest price to the VA (Weighted VA Index), which was compared with the manufacturer index.

RESULTS

The discounted price as a percentage of the WAC ranged from 9 to 74%. All three indexes estimated by the average discount to the VA were at or below the manufacturer indexes (42 vs. 50% for Eli Lilly, 56 vs. 65% for Johnson & Johnson, and 59 vs. 59% for Merck).

CONCLUSIONS

Manufacturer-reported average net prices may provide a close approximation of the average discounted price granted to the VA, suggesting they may be a useful proxy for the true pharmacy benefits manager (PBM) or payer cost. However, individual discounts for products have wide variation, making a standard discount adjustment across multiple products less acceptable.

A Transparent and Consistent Approach to Assess US Outpatient Drug Costs for Use in Cost-Effectiveness Analyses

BACKGROUND

Assessment of drug costs for cost-effectiveness analyses (CEAs) in the United States is not straightforward because the prices paid for drugs are not publicly available and differ between payers. CEAs have relied on list prices that do not reflect the rebates and discounts known to be associated with these purchases.

OBJECTIVES

To review available cost measures and propose a novel strategy that is transparent, consistent, and applicable to all CEAs taking a US health care sector perspective or a societal payer's perspective.

METHODS

We propose using the National Average Drug Acquisition Cost (NADAC), the Veterans Affairs Federal Supply Schedule (VAFSS), and their midpoint as the upper bound, lower bound, and base case, respectively, to estimate net drug prices for various payers. We compare this approach with wholesale acquisition cost (WAC), the most common measure observed in our literature review. The minimum WAC is used to provide the most conservative comparison.

RESULTS

Our sample consists of 1436 brand drugs and 1599 generic drugs. On average, the upper bound (NADAC) is 1% and 9.8% lower than the WAC for brand and generic drugs respectively, whereas the lower bound (VAFSS) is 48.3% and 54.2% lower than the WAC. The NADAC is less than the WAC in 89.6% of drug groups. The distributions of these relationships do not show a clear mode and have wide variation.

CONCLUSIONS

Our study suggests that the WAC may be an overestimate for the base case because the minimum WAC is higher than the NADAC for most drugs. Our approach balances uncertainty and lack of data for the cost of pharmaceuticals with the need for a transparent and consistent approach for valid CEAs.

Innovative assessment of inpatient and pulmonary drug costs for children with cystic fibrosis

BACKGROUND

Previous estimates of the cost of care for pediatric Cystic fibrosis (CF) showed wide variation, without specific summary of pulmonary drug costs.

METHODS

Enrolled CF children from the Wisconsin newborn screening trial were evaluated quarterly per protocol. Assessments systematically included all treatments, hospitalizations, and nutritional and pulmonary outcomes. Direct medical costs from hospital billing and medical records from 1989 to 2010 were used to describe costs by age-ranges and subgroups throughout follow-up. Outpatient drugs were separated by category (pulmonary/otherwise). Inpatient and drug costs were examined by clinical risk factors (presence of meconium ileus, pancreatic insufficiency, and expected severity of genetic mutations).

RESULTS

Seventy-three children were followed for an average of 12.9 years with an average annual total cost of care of $24,768. Outpatient drug costs (53%) and hospitalizations (32%) represented the majority of costs. Drug costs were 48% for pulmonary indications and 52% for non-pulmonary. Pulmonary drug costs for children taking dornase were 54% of their drug costs while pulmonary drug costs were only 31% for children not taking dornase. Significant differences in frequency of inpatient stays existed for children with pancreatic insufficiency. Substantial differences in treatment costs exist as children age and by clinical risk factor.

CONCLUSION

This study provides more accurate longitudinal estimates of CF care costs throughout childhood and shows that increasing age, pancreatic insufficiency, use of dornase, and hospitalizations are key determinants of cost. These estimates can be included in evaluations of the cost-effectiveness of new, highly expensive treatments being introduced for any CF population. Pediatr Pulmonol. 2016;51:1295-1303. © 2016 Wiley Periodicals, Inc.