A comparison of mixture cure fraction models to traditional parametric survival models in estimation of the cost-effectiveness of nivolumab for relapsed small cell lung cancer.

BACKGROUND: In August 2018, the US FDA granted accelerated approval for nivolumab in small cell lung cancer (SCLC) that has progressed after platinum-based chemotherapy and at least one other line of therapy. The objective of this study was to evaluate the cost-effectiveness of nivolumab vs. usual care as third-line (3 L) therapy for patients with recurrent SCLC (rSCLC) from the health payer perspective. Given the potential for a meaningful fraction of treated patients to achieve long-term response to nivolumab, we also assessed the impact of using mixture cure modeling (MCM) vs. parametric survival modeling on survival estimates and cost-effectiveness from the US Medicare payer perspective. METHODS: We created a partitioned survival decision model to assess the cost-effectiveness of 3 L nivolumab vs. usual care in rSCLC, based on observed US treatment patterns. Using this approach, we assessed the impact of extrapolating long-term survival from the CheckMate 032 trial, using both MCM and standard parametric curve fits. Nivolumab survival, resource use, and Grade 3/4 adverse event rates were derived from CheckMate 032. Usual care survival, resource use, and costs were derived from an analysis of patients receiving 3 L treatment for rSCLC in the SEER-Medicare registry. We applied 2020 Wholesale Acquisition Cost for drugs and 2020 CMS reimbursement for procedures. Utilities were derived from the literature. We estimated life years (LY), quality-adjusted life years (QALYs), and costs over a lifetime horizon. RESULTS: MCM and parametric survival model extrapolations resulted in 0.43 versus 0.38 more LYs, 0.34 versus 0.30 more QALYs, and $69,308 versus $61,336 more expenditure for nivolumab vs. usual care, respectively. The costs per QALY gained using mixture cure versus parametric survival modeling were $204,386 and $207,431, respectively. CONCLUSIONS: Mixture cure modeling was equivalent compared to parametric modeling in estimating the cost-effectiveness of nivolumab-based therapy due to the small fraction of patients achieving a long-term response with nivolumab (12.9%).

Current challenges for assessing the long-term clinical benefit of cancer immunotherapy: a multi-stakeholder perspective.

Immuno-oncologics (IOs) differ from chemotherapies as they prime the patient's immune system to attack the tumor, rather than directly destroying cancer cells. The IO mechanism of action leads to durable responses and prolonged survival in some patients. However, providing robust evidence of the long-term benefits of IOs at health technology assessment (HTA) submission presents several challenges for manufacturers. The aim of this article was to identify, analyze, categorize, and further explore the key challenges that regulators, HTA agencies, and payers commonly encounter when assessing the long-term benefits of IO therapies. Insights were obtained from an international, multi-stakeholder steering committee (SC) and expert panels comprising of payers, economists, and clinicians. The selected individuals were tasked with developing a summary of challenges specific to IOs in demonstrating their long-term benefits at HTA submission. The SC and expert panels agreed that standard methods used to assess the long-term benefit of anticancer drugs may have limitations for IO therapies. Three key areas of challenges were identified: (1) lack of a disease model that fully captures the mechanism of action and subsequent patient responses; (2) estimation of longer-term outcomes, including a lack of agreement on ideal methods of survival analyses and extrapolation of survival curves; and (3) data limitations at the time of HTA submission, for which surrogate survival end points and real-world evidence could prove useful. A summary of the key challenges facing manufacturers when submitting evidence at HTA submission was developed, along with further recommendations for manufacturers in what evidence to produce. Despite almost a decade of use, there remain significant challenges around how best to demonstrate the long-term benefit of checkpoint inhibitor-based IOs to HTA agencies, clinicians, and payers. Manufacturers can potentially meet or mitigate these challenges with a focus on strengthening survival analysis methodology. Approaches to doing this include identifying reliable biomarkers, intermediate and surrogate end points, and the use of real-world data to inform and validate long-term survival projections. Wider education across all stakeholders-manufacturers, payers, and clinicians-in considering the long-term survival benefit with IOs is also important.

Accounting for Cured Patients in Cost-Effectiveness Analysis.

BACKGROUND: Economic evaluations often measure an intervention effect with mean overall survival (OS). Emerging types of cancer treatments offer the possibility of being "cured" in that patients can become long-term survivors whose risk of death is the same as that of a disease-free person. Describing cured and noncured patients with one shared mean value may provide a biased assessment of a therapy with a cured proportion. OBJECTIVE: The purpose of this article is to explain how to incorporate the heterogeneity from cured patients into health economic evaluation. METHODS: We analyzed clinical trial data from patients with advanced melanoma treated with ipilimumab (Ipi; n = 137) versus glycoprotein 100 (gp100; n = 136) with statistical methodology for mixture cure models. Both cured and noncured patients were subject to background mortality not related to cancer. RESULTS: When ignoring cured proportions, we found that patients treated with Ipi had an estimated mean OS that was 8 months longer than that of patients treated with gp100. Cure model analysis showed that the cured proportion drove this difference, with 21% cured on Ipi versus 6% cured on gp100. The mean OS among the noncured cohort patients was 10 and 9 months with Ipi and gp100, respectively. The mean OS among cured patients was 26 years on both arms. When ignoring cured proportions, we found that the incremental cost-effectiveness ratio (ICER) when comparing Ipi with gp100 was $324,000/quality-adjusted life-year (QALY) (95% confidence interval $254,000-$600,000). With a mixture cure model, the ICER when comparing Ipi with gp100 was $113,000/QALY (95% confidence interval $101,000-$154,000). CONCLUSIONS: This analysis supports using cure modeling in health economic evaluation in advanced melanoma. When a proportion of patients may be long-term survivors, using cure models may reduce bias in OS estimates and provide more accurate estimates of health economic measures, including QALYs and ICERs.

An expanded portfolio of survival metrics for assessing anticancer agents.

OBJECTIVES: With the introduction of more effective anticancer agents that prolong survival, there is a need for new methods to define the clinical value of treatments. The objective of this preliminary qualitative and quantitative analysis was to assess the utility of an expanded portfolio of survival metrics to differentiate the value of anticancer agents. STUDY DESIGN: A literature review was conducted of phase 3 trial data, reported in regulatory submissions within the last 10 years of agents for 6 metastatic cancers (breast cancer, colorectal cancer [CRC], melanoma, non-small cell lung cancer [NSCLC], prostate cancer [PC], and renal cell cancer [RCC]). METHODS: A new, simplified cost-value analysis tool was applied using survival outcomes and total drug costs. Metrics included median overall survival (OS), mean OS, 1-year survival rate, and number needed to treat (NNT) to avoid 1 death at 1 year. Survival results were compiled and compared both within and across trials by tumor type. Total drug costs were calculated by multiplying each agent's cost per month (from October/November 2013, based on the database Price Rx/Medi-Span) by duration of therapy. RESULTS: Relative clinical value for each agent was not consistent across survival outcomes. In 3 tumor types, both the highest improvement in median OS and the highest improvement in mean OS occurred with the same anticancer agent (ipilimumab with melanoma, pemetrexed with NSCLC, and sunitinib with RCC); the highest improvement in the 1-year survival rate and the lowest NNT occurred together with the same anticancer agent in 5 tumor types (bevacizumab with CRC, ipilimumab with melanoma, erlotinib with NSCLC, abiraterone with PC, and temsirolimus with RCC). In the cost-value analysis, agents were inconsistent and achieved a high relative value with some survival outcomes, but not others. CONCLUSIONS: This analysis suggests that any 1 metric may not completely characterize the expected survival benefit of all patients. The cost-value analysis tool may be applied to trial data and may be useful in helping to make treatment decisions, regardless of the agent's effectiveness. A combined metric will be needed, as well as further research that includes more mature data, other tumor types, and emerging treatments.

Health related quality of life outcomes for unresectable stage III or IV melanoma patients receiving ipilimumab treatment.

BACKGROUND: In an international, randomized Phase III trial ipilimumab demonstrated a significant overall survival benefit in previously treated advanced melanoma patients. This report summarizes health-related quality of life (HRQL) outcomes for ipilimumab with/without gp100 vaccine compared to gp100 alone during the clinical trial's 12 week treatment induction period. METHODS: The Phase III clinical trial (MDX010-20) was a double-blind, fixed dose study in 676 previously treated advanced unresectable stage III or IV melanoma patients. Patients were randomized 3:1:1 to receive either ipilimumab (3 mg/kg q3w x 4 doses) + gp100 (peptide vaccine; 1 mg q3w x 4 doses; ipilimumab plus gp100, n = 403); gp100 vaccine + placebo (gp100 alone, n = 136); or ipilimumab + placebo (ipilimumab alone, n = 137). The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30) assessed HRQL. Baseline to Week 12 changes in EORTC QLQ-C30 function, global health status, and symptom scores were analyzed for ipilimumab with/without gp100 vaccine compared to gp100 alone. Mean change in scores were categorized "no change" (0-5), "a little" (5-10 points), "moderate" (10-20 points), and "very much" (>20). RESULTS: In the ipilimumab plus gp100 and ipilimumab alone groups, mean changes from baseline to Week 12 generally indicated "no change" or "a little" impairment across EORTC QLQ-C30 global health status, function, and symptom subscales. Significant differences in constipation, favoring ipilimumab, were observed (p < 0.05). For ipilimumab alone arm, subscales with no or a little impairment were physical, emotional, cognitive, social function, global health, nausea, pain, dyspnea, constipation, and diarrhea subscales. For the gp100 alone group, the observed changes were moderate to large for global health, role function, fatigue, and for pain. CONCLUSIONS: Ipilimumab with/without gp100 vaccine does not have a significant negative HRQL impact during the treatment induction phase relative to gp100 alone in stage III or IV melanoma patients. TRIAL REGISTRATION: Clinicaltrials.gov identification number NCT00094653.

Persistence with COX-2 inhibitors in managed care: an analysis of claims data.

Drug tolerability strongly influences patients' persistence with treatment. In this study, patterns of medication persistence with cyclooxygenase 2 (COX-2)-specific inhibitors and nonspecific nonsteroidal anti-inflammatory drugs (NSAIDs) were compared in a managed care setting. Pharmacy, enrollment, and medical claims data from 19 health plans were used to match subjects newly treated with celecoxib, rofecoxib, ibuprofen, naproxen, or diclofenac between July 1, 1999 and June 30, 2000. By using multiple regression analysis, users of COX-2-specific inhibitors were found to be 56.8% less likely to discontinue medication use and 60.3% less likely to switch treatment than were users of nonspecific NSAIDs (P < .001). Celecoxib users were 4.6% less likely to discontinue treatment than were rofecoxib users (P < .001). The greater persistence observed among users of COX-2 inhibitors might reflect improved treatment efficacy and patient satisfaction.

The prevalence of cardiorenal risk factors in patients prescribed nonsteroidal anti-inflammatory drugs: data from managed care.

BACKGROUND: Nonsteroidal anti-inflammatory drugs (NSAIDs) have been shown to cause abnormalities in renal function. This is an important concern in patients with cardiorenal risk factors, including hypertension, congestive heart failure, edema, renal impairment, and advanced age. OBJECTIVES: The goals of this study were to determine the prevalence of cardiorenal risk factors in patients with rheumatoid arthritis (RA) or osteoarthritis and ascertain whether these risk factors are associated with prescribing patterns of cyclooxygenase (COX)-2-selective inhibitors and other NSAIDs. METHODS: This was a retrospective, longitudinal claims analysis using data from 19 large independent-practice-model managed care health plans in the United Stated. Three cohorts were identified based on claims for celecoxib, rofecoxib, or other NSAIDs from October 1, 1999, through September 30, 2000. Logistic regression models were used to explore whether baseline cardiorenal risk factors were related to choice of therapy. RESULTS: A total of 77,552 patients received celecoxib (n = 6779 [8.74%]), rofecoxib (n = 7189 [9.27%]), or other NSAIDs (n = 63,584 [81.99%]). Patients prescribed COX-2-selective inhibitors were older than those receiving other NSAIDs and had a diagnosis of RA more often. Overall, 42% of patients had >or=1 cardiorenal risk factor, and approximately one third had hypertension. Cardiorenal risk factors were not related to physicians' prescribing of celecoxib or rofecoxib, but the presence of any cardiorenal risk factor was associated with an increase in the use of COX-2-selective inhibitors compared with other NSAIDs, from 12% for cerebrovascular disease (point estimate, 1.124; P<0.001) to 74% for chronic renal failure/nephritis (point estimate, 1.738; P=0.025). RA and advanced age were associated with the use of celecoxib rather than rofecoxib. CONCLUSIONS: The prevalence of cardiorenal risk factors was found to be similar in patients prescribed celecoxib or rofecoxib for arthritis. Patients with these risk factors were more likely to receive a COX-2-selective inhibitor than other NSAIDs.