Feasibility of Indirect Treatment Comparisons Between Niraparib Plus Abiraterone Acetate and Other First-Line Poly ADP-Ribose Polymerase Inhibitor Treatment Regimens for Patients with BRCA1/2 Mutation-Positive Metastatic Castration-Resistant Prostate Cancer.

INTRODUCTION: Poly(ADP-ribose) polymerase inhibitors (PARPi) are a novel option to treat patients with metastatic castration-resistant prostate cancer (mCRPC). Niraparib plus abiraterone acetate and prednisone (AAP) is indicated for BRCA1/2 mutation-positive mCRPC. Niraparib plus AAP demonstrated safety and efficacy in the phase 3 MAGNITUDE trial (NCT03748641). In the absence of head-to-head studies comparing PARPi regimens, the feasibility of conducting indirect treatment comparisons (ITC) to inform decisions for patients with first-line BRCA1/2 mutation-positive mCRPC has been explored. METHODS: A systematic literature review was conducted to identify evidence from randomized controlled trials on relevant comparators to inform the feasibility of conducting ITCs via network meta-analysis (NMA) or population-adjusted indirect comparisons (PAIC). Feasibility was assessed based on network connectivity, data availability in the BRCA1/2 mutation-positive population, and degree of within- and between-study heterogeneity or bias. RESULTS: NMAs between niraparib plus AAP and other PARPi regimens (olaparib monotherapy, olaparib plus AAP, and talazoparib plus enzalutamide) were inappropriate due to the disconnected network, differences in trial populations related to effect modifiers, or imbalances within BRCA1/2 mutation-positive subgroups. The latter issue, coupled with the lack of a common comparator (except for olaparib plus AAP), also rendered anchored PAICs infeasible. Unanchored PAICs were either inappropriate due to lack of population overlap (vs. olaparib monotherapy) or were restricted by unmeasured confounders and small sample size (vs. olaparib plus AAP). PAIC versus talazoparib plus enzalutamide was not possible due to lack of published arm-level baseline characteristics and sufficient efficacy outcome data in the relevant population. CONCLUSION: The current randomized controlled trial evidence network does not permit robust comparisons between niraparib plus AAP and other PARPi regimens for patients with 1L BRCA-positive mCRPC. Decision-makers should scrutinize any ITC results in light of their limitations. Real-world evidence combined with clinical experience should inform treatment recommendations in this indication.

The Inflation Reduction Act: An Opportunity to Accelerate Confidence in Real-World Evidence in the United States.

OBJECTIVES: The Inflation Reduction Act (IRA), enacted in 2022, brings substantial reforms to the US healthcare system, particularly regarding Medicare. A key aspect includes the introduction of Medicare price negotiation. The objective of this commentary is to explore the implications of the IRA for US pharmaceutical companies, with a specific focus on the role of real-world evidence (RWE) in the context of Medicare reforms. METHODS: This commentary uses a qualitative analysis of the IRA's provisions related to healthcare and pharmaceutical regulation, focusing on how these reforms change the evidence requirements for pharmaceutical companies. It discusses the methodological aspects of generating and using RWE, including techniques such as target trial emulation and quantitative bias analysis methods to address biases inherent in RWE. RESULTS: This commentary highlights that the IRA introduces a unique approach to value assessment in the United States by evaluating drug value several years after launch, as opposed to at launch, similar to health technology assessments in other regions. It underscores the central role of RWE in comparing drug effectiveness across diverse clinical scenarios to improve the accuracy of real-world data comparisons. Furthermore, this article identifies key methodologies for managing the inherent biases in RWE, which are crucial for generating credible evidence for IRA price negotiations. CONCLUSIONS: This article underscores the importance of these methodologies in ensuring credible evidence for IRA price negotiations. It advocates for an integrated approach in evidence generation, positioning RWE as pivotal for informed pricing discussions in the US healthcare landscape.

Carfilzomib, daratumumab, and dexamethasone (KdD) vs. lenalidomide-sparing pomalidomide-containing triplet regimens for relapsed/refractory multiple myeloma: an indirect treatment comparison.

Nearly all patients with multiple myeloma eventually relapse or become refractory to treatment. Lenalidomide is increasingly administered in the frontline until disease progression or intolerance to therapy, resulting in the need for highly effective, lenalidomide-sparing options. In this study, carfilzomib plus daratumumab and dexamethasone were evaluated against lenalidomide-sparing, pomalidomide-containing triplets using matching-adjusted indirect comparison in the absence of head-to-head data. The analyses utilized long-term follow-up data from the CANDOR study (NCT03158688). Treatment with carfilzomib, daratumumab, and dexamethasone resulted in significantly longer progression-free survival (hazard ratio 0.60 [95% confidence interval: 0.37, 0.88])vs. pomalidomide plus bortezomib and dexamethasone, and numerically longer progression-free survival (hazard ratio 0.77 [95% confidence interval: 0.50, 1.08]) vs. daratumumab plus pomalidomide and dexamethasone in patients with relapsed/refractory multiple myeloma and previous lenalidomide exposure, the majority of whom were lenalidomide refractory. Carfilzomib plus daratumumab and dexamethasone offers a highly effective, lenalidomide-sparing treatment option for this population.

Improved estimation of overall survival and progression-free survival for state transition modeling.

Aim: National Institute for Health and Care Excellence guidance (Technical Support Document 19) highlights a key challenge of state transition models (STMs) being their difficulty in achieving a satisfactory fit to the observed within-trial endpoints. Fitting poorly to data over the trial period can then have implications for long-term extrapolations. A novel estimation approach is defined in which the predicted overall survival (OS) and progression-free survival (PFS) extrapolations from an STM are optimized to provide closer estimates of the within-trial endpoints. Materials & methods: An STM was fitted to the SQUIRE trial data in non-small-cell lung cancer (obtained from Project Data Sphere). Two methods were used: a standard approach whereby the maximum likelihood was utilized for the individual transitions and the best-fitting parametric model selected based on AIC/BIC, and a novel approach in which parameters were optimized by minimizing the area between the STM-predicted OS and PFS curves and the corresponding OS and PFS Kaplan-Meier curves. Sensitivity analyses were conducted to assess uncertainty. Results: The novel approach resulted in closer estimations to the OS and PFS Kaplan-Meier for all combinations of parametric distributions analyzed compared with the standard approach. Though the uncertainty associated with the novel approach was slightly larger, it provided better estimates to the restricted mean survival time in 10 of the 12 parametric distributions analyzed. Conclusion: A novel approach is defined which provides an alternative STM estimation method enabling improved fits to modeled endpoints, which can easily be extended to more complex model structures.

MET Exon 14 Skipping in NSCLC: A Systematic Literature Review of Epidemiology, Clinical Characteristics, and Outcomes.

INTRODUCTION: MET exon 14 (METex14) skipping is a rare oncogenic driver in non-small-cell lung cancer (NSCLC) for which targeted therapy with MET tyrosine kinase inhibitors (TKIs) was recently approved. Given the heterogeneity in published data of METex14 skipping NSCLC, we conducted a systematic literature review to evaluate its frequency, patient characteristics, and outcomes. METHODS: On June 13, 2022 we conducted a systematic literature review of publications and conference abstracts reporting frequency, patient characteristics, or outcomes of patients with METex14 skipping NSCLC. RESULTS: We included 139 studies reporting frequency or patient characteristics (350,997 patients), and 39 studies reporting clinical outcomes (3989 patients). Median METex14 skipping frequency was 2.0% in unselected patients with NSCLC, with minimal geographic variation. Median frequency was 2.4% in adenocarcinoma or nonsquamous subgroups, 12.0% in sarcomatoid, and 1.3% in squamous histology. Patients with METex14 skipping NSCLC were more likely to be elderly, have adenocarcinoma histology; there was no marked sex or smoking status distribution. In first line of treatment, median objective response rate ranged from 50.7% to 68.8% with targeted therapies (both values correspond to MET TKIs), was 33.3% with immunotherapy, and ranged from 23.1% to 27.0% with chemotherapy. CONCLUSIONS: Patients with METex14 skipping are more likely to have certain characteristics, but no patient subgroup can be ruled out; thus, it is crucial to test all patients with NSCLC to identify suitable candidates for MET inhibitor therapy. MET TKIs appeared to result in higher efficacy outcomes, although no direct comparison with chemotherapy or immunotherapy regimens was found.

Alone, together: On the benefits of Bayesian borrowing in a meta-analytic setting.

It is common practice to use hierarchical Bayesian model for the informing of a pediatric randomized controlled trial (RCT) by adult data, using a prespecified borrowing fraction parameter (BFP). This implicitly assumes that the BFP is intuitive and corresponds to the degree of similarity between the populations. Generalizing this model to any K ≥ 1 historical studies, naturally leads to empirical Bayes meta-analysis. In this paper we calculate the Bayesian BFPs and study the factors that drive them. We prove that simultaneous mean squared error reduction relative to an uninformed model is always achievable through application of this model. Power and sample size calculations for a future RCT, designed to be informed by multiple external RCTs, are also provided. Potential applications include inference on treatment efficacy from independent trials involving either heterogeneous patient populations or different therapies from a common class.

Evaluation of Cost-Effectiveness of Adjuvant Osimertinib in Patients with Resected EGFR Mutation-Positive Non-small Cell Lung Cancer.

BACKGROUND: For many patients with resected epidermal growth factor receptor mutation-positive (EGFRm) non-small cell lung cancer (NSCLC), current standard of care (SoC) is adjuvant chemotherapy; however, disease recurrence remains high. Based on positive results from ADAURA (NCT02511106), adjuvant osimertinib was approved for treatment of resected stage IB‒IIIA EGFRm NSCLC. OBJECTIVE: The aim was to assess the cost-effectiveness of adjuvant osimertinib in patients with resected EGFRm NSCLC. METHODS: A five-health-state, state-transition model with time dependency was developed to estimate lifetime (38 years) costs and survival of resected EGFRm patients treated with adjuvant osimertinib or placebo (active surveillance), with/without prior adjuvant chemotherapy, using a Canadian Public Healthcare perspective. Transitions between health states were modeled using ADAURA and FLAURA (NCT02296125) data, Canadian life tables, and real-world data (CancerLinQ Discovery®). The model used a 'cure' assumption: patients remaining disease free for 5 years after treatment completion for resectable disease were deemed 'cured.' Health state utility values and healthcare resource usage estimates were derived from Canadian real-world evidence. RESULTS: In the reference case, adjuvant osimertinib treatment led to a mean 3.20 additional quality-adjusted life-years (QALYs; (11.77 vs 8.57) per patient, versus active surveillance. The modeled median percentage of patients alive at 10 years was 62.5% versus 39.3%, respectively. Osimertinib was associated with mean added costs of Canadian dollars (C$)114,513 per patient and a cost/QALY (incremental cost-effectiveness ratio) of C$35,811 versus active surveillance. Model robustness was demonstrated by scenario analyses. CONCLUSIONS: In this cost-effectiveness assessment, adjuvant osimertinib was cost-effective compared with active surveillance for patients with completely resected stage IB‒IIIA EGFRm NSCLC after SoC.

Bayesian hierarchical model-based network meta-analysis to overcome survival extrapolation challenges caused by data immaturity.

Aim: This research evaluated standard Weibull mixture cure (WMC) network meta-analysis (NMA) with Bayesian hierarchical (BH) WMC NMA to inform long-term survival of therapies. Materials & methods: Four trials in previously treated metastatic non-small-cell lung cancer with PD-L1 >1% were used comparing docetaxel with nivolumab, pembrolizumab and atezolizumab. Cure parameters related to a certain treatment class were assumed to share a common distribution. Results: Standard WMC NMA predicted cure rates were 0.03 (0.01; 0.07), 0.18 (0.12; 0.24), 0.07 (0.02; 0.15) and 0.03 (0.00; 0.09) for docetaxel, nivolumab, pembrolizumab and atezolizumab, respectively, with corresponding incremental life years (LY) of 3.11 (1.65; 4.66), 1.06 (0.41; 2.37) and 0.42 (-0.57; 1.68). The Bayesian hierarchical-WMC-NMA rates were 0.06 (0.03; 0.10), 0.17 (0.11; 0.23), 0.12 (0.05; 0.20) and 0.12 (0.03; 0.23), respectively, with incremental LY of 2.35 (1.04; 3.93), 1.67 (0.68; 2.96) and 1.36 (-0.05; 3.64). Conclusion: BH-WMC-NMA impacts incremental mean LYs and cost-effectiveness ratios, potentially affecting reimbursement decisions.

Network meta-interpolation: Effect modification adjustment in network meta-analysis using subgroup analyses.

Effect modification (EM) may cause bias in network meta-analysis (NMA). Existing population adjustment NMA methods use individual patient data to adjust for EM but disregard available subgroup information from aggregated data in the evidence network. Additionally, these methods often rely on the shared effect modification (SEM) assumption. In this paper, we propose Network Meta-Interpolation (NMI): a method using subgroup analyses to adjust for EM that does not assume SEM. NMI balances effect modifiers across studies by turning treatment effect (TE) estimates at the subgroup- and study level into TE and standard errors at EM values common to all studies. In an extensive simulation study, we simulate two evidence networks consisting of four treatments, and assess the impact of departure from the SEM assumption, variable EM correlation across trials, trial sample size and network size. NMI was compared to standard NMA, network meta-regression (NMR) and Multilevel NMR (ML-NMR) in terms of estimation accuracy and credible interval (CrI) coverage. In the base case non-SEM dataset, NMI achieved the highest estimation accuracy with root mean squared error (RMSE) of 0.228, followed by standard NMA (0.241), ML-NMR (0.447) and NMR (0.541). In the SEM dataset, NMI was again the most accurate method with RMSE of 0.222, followed by ML-NMR (0.255). CrI coverage followed a similar pattern. NMI's dominance in terms of estimation accuracy and CrI coverage appeared to be consistent across all scenarios. NMI represents an effective option for NMA in the presence of study imbalance and available subgroup data.

Novel and existing flexible survival methods for network meta-analyses.

Aim: Technical Support Document 21 discusses trial-based, flexible relative survival models. The authors generalized flexible relative survival models to the network meta-analysis (NMA) setting while accounting for different treatment-effect specifications. Methods: The authors compared the standard parametric model with mixture, mixture cure and nonmixture cure, piecewise, splines and fractional polynomial models. The optimal treatment-effect parametrization was defined in two steps. First, all models were run with treatment effects on all parameters and subsequently the optimal model was defined by removing uncertain treatment effects, for which the parameter was smaller than its standard deviation. The authors used a network in previously treated advanced non-small-cell lung cancer. Results: Flexible model-based NMAs impact fit and incremental mean survival and they increase corresponding uncertainty. Treatment-effect specification impacts incremental survival, reduces uncertainty and improves the fit statistic. Conclusion: Extrapolation techniques already available for individual trials can now be used for NMAs to ensure that the most plausible extrapolations are being used for health technology assessment submissions.

Indirect Treatment Comparison of Daratumumab, Pomalidomide, and Dexamethasone Versus Standard of Care in Patients with Difficult-to-Treat Relapsed/Refractory Multiple Myeloma.

INTRODUCTION: The phase 3 APOLLO study demonstrated significantly better progression-free survival (PFS) and clinical responses with daratumumab, pomalidomide, and dexamethasone (D-Pd) versus pomalidomide and dexamethasone (Pd) in patients with relapsed/refractory multiple myeloma (RRMM). On the basis of these results and those from the phase 1b EQUULEUS trial, D-Pd was approved in this patient population. In the absence of head-to-head data comparing D-Pd with further standard of care (SOC) therapies, indirect treatment comparisons (ITCs) can provide important information to help optimize treatment selection. The objective of this study was to indirectly compare PFS improvement with D-Pd versus daratumumab, bortezomib, and dexamethasone (D-Vd) and D-Pd versus bortezomib and dexamethasone (Vd) in patients with RRMM. METHODS: Patient-level data were from APOLLO, EQUULEUS, and CASTOR. Three methods of adjusting imbalances in baseline characteristics including stabilized inverse probability of treatment weighting (sIPTW), cardinality matching (CM), and propensity score matching (PSM) were initially considered. CM offers mathematically guaranteed largest matched sample meeting pre-specified maximum standardized mean difference criteria for matching covariates. sIPTW and PSM were based on propensity scores derived from logistic regression. Feasibility assessment of the PSM method returned too low effective sample size to support a meaningful comparison. CM was chosen as the base case and sIPTW as a sensitivity analysis. RESULTS: After harmonized eligibility criteria were applied, 253, 104, and 122 patients from the D-Pd, D-Vd, and Vd cohorts, respectively, were included in the ITC analyses. Some imbalances in baseline characteristics were identified between D-Pd and D-Vd/Vd cohorts that remained after adjustment. PFS hazard ratios showed significant improvement for D-Pd over D-Vd and Vd for CM and sIPTW analyses. CONCLUSIONS: Results showed consistent PFS benefit for D-Pd versus D-Vd and Vd regardless of the adjustment technique used. These findings support the use of D-Pd versus D-Vd or Vd in patients with difficult-to-treat RRMM. TRIAL REGISTRATION: NCT03180736; NCT02136134, NCT01998971.

Bridging the gap between oncology clinical trials and real-world data: evidence on replicability of efficacy results using German claims data.

Aims: Using German claims, the authors replicated the CHAARTED trial in metastatic hormone-sensitive prostate cancer. Methods: The authors identified metastatic hormone-sensitive prostate cancer patients replicating the inclusion/exclusion criteria of CHAARTED. Patients treated with docetaxel in combination with androgen deprivation therapy (ADT) at first line (docetaxel group) were compared with patients treated with ADT monotherapy (ADT mono group). After propensity score matching, overall survival was compared between the matched cohorts. Results: The authors included 441 patients. After propensity score matching, two equally sized matched cohorts of 74 patients each were compared in terms of overall survival. The hazard ratio (HR) was 0.71 (95% CI: 0.42-1.19), comparable to the HR in CHAARTED (HR: 0.72; 95% CI: 0.59-0.89). Conclusions: Using early comparative evidence from real-world data for regulatory and health technology assessment decisions is useful.

Efficacy of non-intensive therapies approved for relapsed/refractory acute myeloid leukemia: a systematic literature review.

Aim: De novo relapsed and/or refractory acute myeloid leukemia (rrAML) has limited treatment options for patients not eligible ('unfit') to receive intensive chemotherapy-based interventions. The authors aimed to summarize outcomes for licensed therapies in this setting. Materials & methods: A systematic literature review identified licensed therapies in this setting. A feasibility assessment was made to conduct a network meta-analysis to evaluate comparative efficacy. Results: Seven unique trials were identified. Median survival months were 13.8 for gemtuzumab ozogamicin (GO), 9.3 for gilteritinib (FLT3 mutated rrAML), 5.6 for low-dose cytarabine and 3.2 for best supportive care; transplant rates with gilteritinib and GO were 25.5 and 19%, respectively. A network meta-analysis was not feasible. Conclusion: There remains a high unmet need in de novo rrAML patients not eligible for intensive therapy, with GO and gilteritinib (only FLT3-mutated AML) providing the best current options.

Some patients with acute myeloid leukemia (AML) have no response to initial treatment or have a response that is subsequently lost. Follow-on treatment options after that initial stage are limited, especially for patients who are not able to have intensive therapy, such as chemotherapy, due to age, physical or cognitive function, existing comorbidities or symptoms. This study aimed to review the published literature to identify data associated with treatments that are licensed for use in patients ineligible for intensive therapy who do not maintain a response from their initial therapy. The study found that the drug gilteritinib was an option for the subgroup of AML patients with FLT3-mutated disease with an average life expectancy just under 1 year, while gemtuzumab ozogamicin was an option for a wider group of AML patients with a life expectancy just over 1 year. Between a fifth and a quarter of patients went on to receive a stem-cell transplant after treatment with one of these. With limited options, this patient group needs further attention; however, the availability of the previously mentioned treatments is promising.

Health impact of tafamidis in transthyretin amyloid cardiomyopathy patients: an analysis from the Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT) and the open-label long-term extension studies.

AIM: The Tafamidis in Transthyretin Cardiomyopathy Clinical Trial (ATTR-ACT) showed that tafamidis reduced all-cause mortality and cardiovascular-related hospitalizations in patients with transthyretin amyloid cardiomyopathy (ATTR-CM). This study aimed to estimate the impact of tafamidis on survival and quality-adjusted life-years (QALYs). METHODS AND RESULTS: A multi-state, cohort, Markov model was developed to simulate the disease course of ATTR-CM throughout a lifetime. For survival extrapolation, survival curves were fitted by treatment arm and New York Heart Association (NYHA) Class I/II (68% of patients) and NYHA Class III (32% of patients) cohorts using the individual patient-level data from both the ATTR-ACT and the corresponding long-term extension study. Univariate and multivariate sensitivity analyses were conducted. The predicted mean survival for the total population (NYHA Class I/II + III) was 6.73 years for tafamidis and 2.85 years for the standard of care (SoC), resulting in an incremental mean survival of 3.88 years [95% confidence interval (CI) 1.32-5.66]. Of the 6.73 life-years, patients on tafamidis spend, on average, 4.82 years in NYHA Class I/II, while patients on SoC spend an average of 1.60 life-years in these classes. The combination of longer survival in lower NYHA classes produced a QALY gain of 5.39 for tafamidis and 2.11 for SoC, resulting in 3.29 incremental QALYs (95% CI 1.21-4.74) in favour of tafamidis. CONCLUSION: Based on the disease simulation model results, tafamidis is expected to more than double the life expectancy and QALYs of ATTR-CM patients compared to SoC. Longer-term follow-up data from the ATTR-ACT extension study will further inform these findings. CLINICAL TRIALS.GOV IDENTIFIER: NCT01994889 (date of registration: 26 November 2013).

Comparison of Parametric Survival Extrapolation Approaches Incorporating General Population Mortality for Adequate Health Technology Assessment of New Oncology Drugs.

OBJECTIVES: Survival extrapolation of trial outcomes is required for health economic evaluation. Generally, all-cause mortality (ACM) is modeled using standard parametric distributions, often without distinguishing disease-specific/excess mortality and general population background mortality (GPM). Recent National Institute for Health and Care Excellence guidance (Technical Support Document 21) recommends adding GPM hazards to disease-specific/excess mortality hazards in the log-likelihood function ("internal additive hazards"). This article compares alternative extrapolation approaches with and without GPM adjustment. METHODS: Survival extrapolations using the internal additive hazards approach (1) are compared to no GPM adjustment (2), applying GPM hazards once ACM hazards drop below GPM hazards (3), adding GPM hazards to ACM hazards (4), and proportional hazards for ACM versus GPM hazards (5). The fit, face validity, mean predicted life-years, and corresponding uncertainty measures are assessed for the active versus control arms of immature and mature (30- and 75-month follow-up) multiple myeloma data and mature (64-month follow-up) breast cancer data. RESULTS: The 5 approaches yielded considerably different outcomes. Incremental mean predicted life-years vary most in the immature multiple myeloma data set. The lognormal distribution (best statistical fit for approaches 1-4) produces survival increments of 3.5 (95% credible interval: 1.4-5.3), 8.5 (3.1-13.0), 3.5 (1.3-5.4), 2.9 (1.1-4.5), and 1.6 (0.4-2.8) years for approaches 1 to 5, respectively. Approach 1 had the highest face validity for all data sets. Uncertainty over parametric distributions was comparable for GPM-adjusted approaches 1, 3, and 4, and much larger for approach 2. CONCLUSION: This study highlights the importance of GPM adjustment, and particularly of incorporating GPM hazards in the log-likelihood function of standard parametric distributions.

Comparing cure rates for gemtuzumab ozogamicin plus standard chemotherapy vs standard chemotherapy alone in acute myeloid leukemia patients.

Aim: Assess the suitability of standard parametric, piecewise and mixture cure models (MCMs) for modeling long-term survival of acute myeloid leukemia patients achieving remission following treatment with gemtuzumab ozogamicin (GO) + standard chemotherapy (SC) or SC alone. MCMs can model survival data comprising of statistically cured (patients in long-term remission) and uncured patients. Materials & methods: Models were fit to patient-level data corresponding to individual treatment arms. Results: Visual inspection showed that MCMs fit the clinical data best. Survival modeling with MCMs showed that treatment with GO + SC versus SC alone results in higher statistical cure rates for event-free survival (rates: 26-35% vs 21-23%) and overall survival (rates: 48-52% vs 38-44%). Conclusion: MCMs are well suited to modeling long-term survival in acute myeloid leukemia patients. Clinical trial registration: NCT00927498 (ClinicalTrials.gov).

Lay abstract To assess the effectiveness of acute myeloid leukemia (AML) treatments, researchers use statistical models to estimate the survival rate of patients who receive a particular treatment. Some patients receiving certain AML treatments can achieve long-term remission and are often considered 'cured'. Standard statistical models cannot differentiate between cured and uncured patients and so tend to underestimate the survival rates of cured patients. Mixture cure models (MCMs) can account separately for the survival of cured versus uncured patients. We tested MCMs and standard statistical models using data from a clinical trial comparing gemtuzumab ozogamicin (GO) + standard chemotherapy against standard chemotherapy alone in AML patients. Of all the models tested, MCMs generated survival extrapolations over time that most closely resembled the data from the clinical trial. Through our analyses, we demonstrated that GO + standard chemotherapy can result in higher survival rates than standard chemotherapy alone.

An indirect comparison between bosutinib, nilotinib and dasatinib in first-line chronic phase chronic myeloid leukemia.

OBJECTIVE: Bosutinib, nilotinib and dasatinib are approved for the treatment of patients with newly diagnosed chronic-phase chronic myeloid leukemia (CP-CML). In the absence of head-to-head comparisons between second-generation tyrosine kinase inhibitors (TKIs), the objective of this study was to indirectly compare the efficacy of bosutinib with nilotinib and dasatinib in first-line (1L) CP-CML. METHODS: Cross-trial heterogeneity in terms of patient baseline characteristics and imatinib dose escalation are difficult to adjust for in network meta-analyses and anchored matching-adjusted indirect treatment comparisons (MAICs). Therefore, an unanchored MAIC was performed using patient level data from bosutinib (BFORE trial) and published aggregated data from nilotinib (ENESTnd) and dasatinib (DASISION) trials. After matching, cytogenetic and molecular responses, and disease progression, after a minimum follow-up of 24 months were compared between nilotinib versus bosutinb and dasatinib versus bosutinib. RESULTS: The comparison of nilotinib versus bosutinib resulted in no statistically significant differences for MMR at and by 24 months, MR4 by 24 months, MR4.5 at and by 24 months, CCyR by 24 months, and disease progression, however, a decreased odds of MR4 at 24 months in favor of bosutinib versus nilotinib was observed. The comparison of dasatinib versus bosutinib by 24 months resulted in no statistically significant differences for MMR, disease progression, and CCyR, however a decreased odds of MR4.5 in favor of bosutinib versus dasatinib was observed. CONCLUSIONS: Overall, in these analyses bosutinib demonstrates equivalent efficacy to nilotinib and dasatinib in the treatment of patients with newly diagnosed CP-CML.

The cost-effectiveness of glasdegib in combination with low-dose cytarabine, for the treatment of newly diagnosed acute myeloid leukemia in adult patients who are not eligible to receive intensive induction chemotherapy in Canada.

AIM: The clinical efficacy and safety of DAURISMO (glasdegib) combined with low-dose cytarabine (LDAC) were demonstrated in the BRIGHT AML 1003 study among newly diagnosed acute myeloid leukemia patients who are not eligible to receive intensive chemotherapy. This study aims to evaluate its cost-effectiveness versus LDAC alone and azacitidine from a Canadian payer perspective. MATERIALS AND METHODS: A partitioned-survival model was developed with three health states: progression-free survival (PFS), relapse/progression and death. Clinical inputs were obtained from the BRIGHT AML 1003 study for glasdegib and LDAC, and from the two trial publications and indirect treatment comparison for azacitidine. Drug acquisition/administration, disease management, adverse event and end-of-life costs were considered. All costs were measured in Canadian dollars. Cost-effectiveness of glasdegib + LDAC was assessed against LDAC alone in main population, and against azacitidine by bone marrow blasts (BMB). A weighted average ICER was calculated to represent the current treatment use of Canadian clinical practice. The reference-case analysis was conducted probabilistically, and numerous probabilistic scenario analyses were conducted. RESULTS: The incremental cost-effectiveness ratios (ICERs) compared to LDAC alone was CAD $177,065 (a mean gain of 0.41 QALYs and an incremental cost of CAD $72,695), to azacitidine in 20-30% and >30% BMB group were CAD $178,201 (a mean gain of 0.34 QALYs and an incremental cost of CAD $59,889) and dominant (a mean gain of 0.28 QALYs while reducing costs by CAD $7,856) respectively, resulting in a weighted average ICER of CAD $81,310 per QALY. LIMITATIONS AND CONCLUSIONS: Though uncertainties remain with the generated PFS curve, the derived azacitidine curves, administration and vial wastage, the model has been built under the best available evidence and relied on clinical opinions where there were data gaps. The weighted average ICER suggests that glasdegib + LDAC is cost-effective at a CAD $100,000 willingness-to-pay threshold.

Comparative efficacy and safety of bortezomib, thalidomide, and dexamethasone (VTd) without and with daratumumab (D-VTd) in CASSIOPEIA versus VTd in PETHEMA/GEM in transplant-eligible patients with newly diagnosed multiple myeloma, using propensity score matching.

Background: Traditional bortezomib, thalidomide, and dexamethasone (VTd) regimens for patients with newly diagnosed multiple myeloma (NDMM) include doses of thalidomide up to 200 mg/day (VTd-label). Clinical practice has evolved to use a lower dose (100 mg/day) to reduce toxicity (VTd-mod), which was evaluated in the phase III CASSIOPEIA study, without or with daratumumab (D-VTd; an anti-CD38 monoclonal antibody). We used propensity score matching to compare efficacy and safety for VTd-mod and D-VTd with VTd-label. Methods: Patient-level data for VTd-mod and D-VTd from CASSIOPEIA (NCT02541383) and data for VTd-label from the PETHEMA/GEM study (NCT00461747) were analyzed. Propensity scores were estimated using logistic regression, and nearest-neighbor matching procedure was used. Outcomes included overall survival (OS), progression-free survival (PFS), time to progression (TTP), postinduction and posttransplant responses, as well as rate of treatment discontinuation and grade 3/4 peripheral neuropathy. Results: VTd-mod was noninferior to VTd-label for OS, PFS, TTP, postinduction very good partial response or better (≥VGPR) and overall response rate (ORR). VTd-mod was significantly better for posttransplant ≥VGPR and ORR versus VTd-label. VTd-mod safety was not superior to VTd-label despite the lower thalidomide dose. D-VTd was significantly better than VTd-label for OS, PFS, TTP, postinduction and posttransplant ≥VGPR and ORR, and was noninferior to VTd-label for safety outcomes. Conclusions: In transplant-eligible patients with NDMM, D-VTd had superior efficacy compared with VTd-label. Despite a lower dose of thalidomide, VTd-mod was noninferior to VTd-label for safety and was significantly better for posttransplant ≥VGPR/ORR. These data further support the first-line use of daratumumab plus VTd.

A large meta-analysis establishes the role of MRD negativity in long-term survival outcomes in patients with multiple myeloma.

The prognostic value of minimal residual disease (MRD) for progression-free survival (PFS) and overall survival (OS) was evaluated in a large cohort of patients with multiple myeloma (MM) using a systematic literature review and meta-analysis. Medline and EMBASE databases were searched for articles published up to 8 June 2019, with no date limit on the indexed database. Clinical end points stratified by MRD status (positive or negative) were extracted, including hazard ratios (HRs) on PFS and OS, P values, and confidence intervals (CIs). HRs were estimated based on reconstructed patient-level data from published Kaplan-Meier curves. Forty-four eligible studies with PFS data from 8098 patients, and 23 studies with OS data from 4297 patients were identified to assess the association between MRD status and survival outcomes. Compared with MRD positivity, achieving MRD negativity improved PFS (HR, 0.33; 95% CI, 0.29-0.37; P < .001) and OS (HR, 0.45; 95% CI, 0.39-0.51; P < .001). MRD negativity was associated with significantly improved survival outcomes regardless of disease setting (newly diagnosed or relapsed/refractory MM), MRD sensitivity thresholds, cytogenetic risk, method of MRD assessment, depth of clinical response at the time of MRD measurement, and MRD assessment premaintenance and 12 months after start of maintenance therapy. The strong prognostic value of MRD negativity and its association with favorable outcomes in various disease and treatment settings sets the stage to adopt MRD as a treatment end point, including development of therapeutic strategies. This large meta-analysis confirms the utility of MRD as a relevant surrogate for PFS and OS in MM.