An adjusted indirect comparison of everolimus and sorafenib therapy in sunitinib-refractory metastatic renal cell carcinoma patients using repeated matched samples

Comparative effectiveness of lazertinib in patients with EGFR T790M-positive non-small-cell lung cancer using a real-world external control

Lazertinib is a recently developed third-generation epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors used for patients with advanced EGFR T790M-positive non-small-cell lung cancer. We evaluated the effectiveness of lazertinib compared with osimertinib using an external control. We obtained individual patient data for the lazertinib arm from the LASER201 trial and the osimertinib arm from registry data at the Samsung Medical Center. In total, 75 and 110 patients were included in the lazertinib and osimertinib groups, respectively. After propensity score matching, each group had 60 patients and all baseline characteristics were balanced. The median follow-up duration was 22.0 and 29.6 months in the lazertinib and osimertinib group, respectively. The objective response rate (ORR) were 76.7% and 86.7% for lazertinib and osimertinib, respectively (p = 0.08). The median progression-free survival (PFS) was 12.3 months (95% confidence interval [CI] 9.5-19.1) and 14.4 months (95% CI 11.8-18.1) for the lazertinib and osimertinib group, respectively (hazard ratio [HR] 0.97; 95% CI 0.64-1.45, p = 0.86). The median overall survival with lazertinib was not reached and that with osimertinib was 29.8 months (HR 0.44; 95% CI 0.25-0.77, p = 0.005). Our study suggests that lazertinib has an ORR and PFS comparable to those of osimertinib and has the potential for superior survival benefits.

Survival Outcomes of Patients With Tropomyosin Receptor Kinase Fusion-Positive Cancer Receiving Larotrectinib Versus Standard of Care: A Matching-Adjusted Indirect Comparison Using Real-World Data

PURPOSE

Larotrectinib, a highly specific tropomyosin receptor kinase (TRK) inhibitor, previously demonstrated high response rates in single-arm trials of patients with TRK fusion-positive cancer, but there are limited data on comparative effectiveness against standard-of-care (SoC) regimens used in routine health care practice, before widespread adoption of TRK inhibitors as SoC for TRK fusion-positive cancers. Matching-adjusted indirect comparison, a validated methodology that balances population characteristics to facilitate cross-trial comparisons, was used to compare the overall survival (OS) of larotrectinib versus non-TRK-inhibitor SoC.

MATERIALS AND METHODS

Individual patient data from three larotrectinib trials (ClinicalTrials.gov identifiers: NCT02122913, NCT02637687, and NCT02576431) were compared with published aggregate real-world data from patients with locally advanced/metastatic TRK fusion-positive cancer identified in the Flatiron Health/Foundation Medicine database. OS was defined as the time from advanced/metastatic disease diagnosis to death. After matching population characteristics, the analyses included (1) a log-rank test of equality to test whether the two groups were similar before larotrectinib initiation; and (2) estimation of treatment effect of larotrectinib versus non-TRK-inhibitor SoC. These analyses are limited to prognostic variables available in real-world data.

RESULTS

Eighty-five larotrectinib patients and 28 non-TRK-inhibitor SoC patients were included in the analyses. After matching, log-rank testing showed no difference in baseline characteristics between the two groups (P = .31). After matching, larotrectinib was associated with a 78% lower risk of death, compared with non-TRK-inhibitor SoC (adjusted hazard ratio, 0.22 [95% CI, 0.09 to 0.52]; P = .001); median OS was 39.7 months (95% CI: 16.4, NE [not estimable]) for larotrectinib and 10.2 months (95% CI: 7.2, 14.1) for SoC.

CONCLUSION

Matching-adjusted indirect comparison analyses suggest longer OS with larotrectinib, compared with non-TRK-inhibitor SoC, in adult patients with TRK fusion-positive cancer.

Matching-adjusted indirect comparison via a polynomial-based non-linear optimisation method

Aim: To demonstrate the potential of fourth-order polynomials within a non-linear optimisation framework for matching-adjusted indirect comparison (MAIC). Materials & methods: Simulated individual patient data were reweighted via fourth-order polynomials (polyMAIC) to match aggregate-level data across multiple baseline characteristics. The polyMAIC approach employed pre-specified matching tolerances and maximum allowable weights. Matching performance against aggregate-level targets was assessed, and also compared against the current industry-standard MAIC approach (Signorovitch). Results: The polyMAIC method matched aggregate-level targets within pre-specified tolerances. Effective sample sizes were either similar to or somewhat higher than those obtained from the Signorovitch method. Performance gains from polyMAIC tended to increase as matching complexity increased. Conclusion: PolyMAIC incorporates greater flexibility than the industry-standard MAIC approach and demonstrates matching potential.

Systemic therapy in metastatic renal cell carcinoma: Emerging challenges in therapeutic choice

The treatment landscape for metastatic renal cell carcinoma (mRCC) has undergone a substantial evolution in the past decade, with a dramatic increase in the number of available systemic therapies. Although this offers promise for improved patient outcomes, this rapid pace in development has led to new challenges in therapeutic choice. For instance, the absence of direct comparative evidence across all therapeutic options has led to a critical gap in evidence to clearly define preferred systemic therapy choice. Additionally, the rising cost of systemic therapies being evaluated for mRCC necessitates demonstration of cost-effectiveness prior to widespread adoption. This review provides an overview of the current treatment landscape in mRCC to highlight the emerging challenges faced by clinicians and health policy-makers. In addition, this review summarizes the currently available evidence that aims to address the above challenges.

Matching-adjusted indirect comparisons of annualized bleeding rate and utilization of BAY 94-9027 versus three recombinant factor VIII agents for prophylaxis in patients with severe hemophilia A

Background: BAY 94-9027 is an extended half-life recombinant factor VIII (rFVIII) that prevents bleeding in persons with hemophilia A at twice-weekly, 5-day, and 7-day dosing intervals. In rare diseases such as hemophilia, where small populations preclude head-to-head comparisons in randomized controlled trials, outcomes from different studies can be compared by matching-adjusted indirect treatment comparisons (MAICs) via matched summary statistics of individual patient data. This study compared MAIC-adjusted outcomes of BAY 94-9027 with other FVIII agents for prophylaxis of hemophilia. Methods: Weighted patient data from the BAY 94-9027 PROTECT VIII trial were used to compare annualized bleeding rates (ABRs), percentage of patients with zero bleeds, and factor utilization against published data on rFVIII-Fc fusion protein (rFVIIIFc), BAX 855, and recombinant antihemophilic factor/plasma/albumin-free method (rAHF-PFM). Results: After matching BAY 94-9027 and comparators, the mean BAY 94-9027 utilization was significantly lower than rFVIIIFc pre- and post-matching (66.2 vs 82.2 IU/kg/week; 66.5 vs 82.2 IU/kg/week; both P<0.001). Median BAY 94-9027 utilization (IU/kg/week) trended lower than BAX 855 (64.3 vs 87.4) and rAHF-PFM (2004 study: 64.0 vs 107.5; 2012 study: 63.6 vs 109.9). Mean ABRs and percentages of patients with zero bleeds were similar post-matching between BAY 94-9027 and comparators. Conclusion: BAY 94-9027 demonstrated similar MAIC-adjusted ABR with lower utilization than rFVIIIFc, BAX 855, and rAHF-PFM.

Comparative effectiveness from a single-arm trial and real-world data: alectinib versus ceritinib

Aim: To compare the overall survival of anaplastic lymphoma kinase-positive non-small-cell lung cancer patients who received alectinib with those who received ceritinib. Materials & methods: Two treatment arms (alectinib [n = 183] and ceritinib [n = 67]) were extracted from clinical trials and an electronic health record database, respectively. Propensity scores were applied to balance baseline characteristics. Kaplan–Meier and multivariate Cox regression were conducted. Results: After propensity score adjustment, baseline characteristics were balanced. Alectinib had a prolonged median overall survival (alectinib = 24.3 months and ceritinib = 15.6 months) and lower risk of death (hazard ratio: 0.65; 95% CI: 0.48–0.88). Conclusion: Alectinib was associated with prolonged overall survival versus ceritinib, which is consistent with efficacy evidence from clinical trials.

A review of methods for comparing treatments evaluated in studies that form disconnected networks of evidence

A network meta-analysis allows a simultaneous comparison between treatments evaluated in randomised controlled trials that share at least one treatment with at least one other study. Estimates of treatment effects may be required for treatments across disconnected networks of evidence, which requires a different statistical approach and modelling assumptions to account for imbalances in prognostic variables and treatment effect modifiers between studies. In this paper, we review and discuss methods for comparing treatments evaluated in studies that form disconnected networks of evidence. Several methods have been proposed but assessing which are appropriate often depends on the clinical context as well as the availability of data. Most methods account for sampling variation but do not always account for others sources of uncertainty. We suggest that further research is required to assess the properties of methods and the use of approaches that allow the incorporation of external information to reflect parameter and structural uncertainty.

Evaluating Matching-Adjusted Indirect Comparisons in Practice: A Case Study of Patients with Attention-Deficit/Hyperactivity Disorder

Differences in patient characteristics across trials may bias efficacy estimates from indirect treatment comparisons. To address this issue, matching-adjusted indirect comparison (MAIC) measures treatment efficacy after weighting individual patient data to match patient characteristics across trials. To date, however, there is no consensus on how best to implement MAIC. To address this issue, we applied MAIC to measure how two attention-deficit/hyperactivity disorder (ADHD) treatments (guanfacine extended release and atomoxetine hydrochloride) affect patients' ADHD symptoms, as measured by the ADHD Rating Scale IV score. We tested MAIC sensitivity to: matched patient characteristics, matched statistical moments, weighting matrix, and placebo-arm matching (i.e., matching on outcomes in the placebo arm). After applying MAIC, guanfacine and atomoxetine had similar reductions in ADHD symptoms (Δ: 0.4, p < 0.737). The results were similar for three of four sensitivity analyses. When we applied MAIC with placebo-arm matching, however, guanfacine reduced symptoms more than atomoxetine (Δ: -3.9, p < 0.004). We discuss the implication of this finding and advise MAIC practitioners to carefully consider the use of placebo-arm matching, depending on the presence of residual confounding across trials. Copyright © 2016 John Wiley & Sons, Ltd.

Methods for Population-Adjusted Indirect Comparisons in Health Technology Appraisal

Standard methods for indirect comparisons and network meta-analysis are based on aggregate data, with the key assumption that there is no difference between the trials in the distribution of effect-modifying variables. Methods which relax this assumption are becoming increasingly common for submissions to reimbursement agencies, such as the National Institute for Health and Care Excellence (NICE). These methods use individual patient data from a subset of trials to form population-adjusted indirect comparisons between treatments, in a specific target population. Recently proposed population adjustment methods include the Matching-Adjusted Indirect Comparison (MAIC) and the Simulated Treatment Comparison (STC). Despite increasing popularity, MAIC and STC remain largely untested. Furthermore, there is a lack of clarity about exactly how and when they should be applied in practice, and even whether the results are relevant to the decision problem. There is therefore a real and present risk that the assumptions being made in one submission to a reimbursement agency are fundamentally different to—or even incompatible with—the assumptions being made in another for the same indication. We describe the assumptions required for population-adjusted indirect comparisons, and demonstrate how these may be used to generate comparisons in any given target population. We distinguish between anchored and unanchored comparisons according to whether a common comparator arm is used or not. Unanchored comparisons make much stronger assumptions, which are widely regarded as infeasible. We provide recommendations on how and when population adjustment methods should be used, and the supporting analyses that are required to provide statistically valid, clinically meaningful, transparent and consistent results for the purposes of health technology appraisal. Simulation studies are needed to examine the properties of population adjustment methods and their robustness to breakdown of assumptions.

Panobinostat Plus Bortezomib Versus Lenalidomide in Patients with Relapsed and/or Refractory Multiple Myeloma: A Matching-Adjusted Indirect Treatment Comparison of Survival Outcomes using Patient-level Data

BACKGROUND

In the UK, the standard of care for patients with multiple myeloma who received ≥2 prior treatments is lenalidomide plus dexamethasone (LEN + DEX) and pomalidomide plus DEX (POM + DEX) (in Wales only). Recently, panobinostat plus bortezomib and DEX (PAN + BTZ + DEX) was licensed in this setting. The current study assessed the progression-free survival (PFS) and overall survival (OS) outcomes with PAN + BTZ + DEX versus LEN + DEX (primary comparator) and POM + DEX (exploratory comparator).

METHODS

Since an anchor-based indirect treatment comparison was not feasible, the matching-adjusted indirect treatment comparison approach was used. To compare the survival outcomes, patient-level data were generated for the comparators utilizing published Kaplan-Meier survival estimates. The use of approximated patient-level data and matched data for PAN + BTZ + DEX allowed the use of Cox proportional hazards models and the assessment of the proportional hazards assumption. In cases where there was evidence that the proportional hazards assumption was violated, time-dependent hazard ratios (HRs) were estimated. Median and mean values for PFS and OS were predicted.

RESULTS

For both PFS and OS, the proportional hazards assumption was not satisfied, therefore time-dependent HRs were estimated. Using time-dependent HRs, the mean PFS was estimated to be 11.83 months for PAN + BTZ + DEX and 10.96 months for LEN + DEX. The corresponding mean OS estimates were 30.73 and 27.76 months, respectively. Comparisons with POM + DEX were affected by large uncertainty and did not allow making robust inferences.

CONCLUSIONS

To our knowledge, this is the first study that combined matching-adjusted indirect treatment comparison with time-dependent HRs to address changing patterns in the HR. The results suggest that treatment with PAN + BTZ + DEX and LEN + DEX are associated with similar mean PFS and OS in the third-line treatment setting of multiple myeloma.

Review and comparison of methodologies for indirect comparison of clinical trial results: an illustration with ranibizumab and aflibercept

AIM

To review and compare methods for indirect comparison of aflibercept and ranibizumab in patients with diabetic macular edema.

METHODS

Post-stratification, inverse probability weighting based on simulated data, weight optimization, and regression model techniques were used to compare pooled individual patient-level data from the RESTORE and RESPOND (ranibizumab 0.5 mg as needed after 3 initial monthly doses) studies with summary-level data from the VIVID and VISTA (aflibercept 2.0 mg every 8 weeks after 5 initial monthly doses, 2q8) studies. The impact of adjusting for up to two baseline characteristics was assessed.

RESULTS

All methods provided similar results. After adjustment for baseline best-corrected visual acuity and central retinal thickness, no statistically significant difference in average gain in baseline best-corrected visual acuity from baseline at month 12 was found between ranibizumab 0.5 mg and aflibercept 2q8.

CONCLUSIONS

Weight optimization and regression methods are useful options to adjust for more than one baseline characteristic.

Molecular analysis of sunitinib resistant renal cell carcinoma cells after sequential treatment with RAD001 (everolimus) or sorafenib

Sequential application of target drugs is standard procedure after renal cell carcinoma (RCC) patients develop resistance. To optimize the sequence, antitumour effects of the mTOR inhibitor RAD001 or the tyrosine kinase inhibitor (TKI) sorafenib on RCC cells with acquired resistance to the TKI sunitinib was evaluated. RCC cells were exposed to 1 μM sunitinib for 24 hrs (as control) and for 8 weeks (to induce resistance) and then switched to RAD001 (5 nM) or sorafenib (5 μM) for a further 8 weeks. Tumour cell growth, cell cycle progression, cell cycle regulating proteins and intracellular signalling were then investigated. Short-term application of sunitinib (24 hrs) induced cell growth blockade with accumulation in the G2/M phase. RCC cells became resistant to sunitinib after 8 weeks, demonstrated by accelerated cell growth along with enhanced cdk1, cdk2, loss of p27, activation of Akt, Rictor and Raptor. Switching to sorafenib only slightly reduced growth of the sunitinib resistant RCC cells and molecular analysis indicated distinct cross-resistance. In contrast, full response was achieved when the cancer cells were treated with RAD001. p19 and p27 strongly increased, phosphorylated Akt, Rictor and Raptor decreased and the tumour cells accumulated in G0/G1. It is concluded that an mTOR-inhibitor for second-line therapy could be the strategy of choice after first-line sunitinib failure.

Treatment patterns in metastatic renal cell carcinoma: a retrospective review of medical records from US community oncology practices

BACKGROUND

Vascular endothelial growth factor (VEGF) inhibitors, including targeted therapy with tyrosine kinase inhibitors (TKIs) and the angiogenesis inhibitor bevacizumab, and mammalian target of rapamycin (mTOR) inhibitors are now the standard of care for metastatic renal cell carcinoma (mRCC). However, real-world treatment patterns are not well characterized.

OBJECTIVE

To describe treatment patterns during the first, second, and third lines of targeted therapies for mRCC among community oncologists in the US.

METHODS

Participating physicians recruited from a nationwide panel each identified up to 15 adult mRCC patients who initiated a second therapy after January 2010. Information extracted from medical records included types of targeted therapies, reasons for treatment choices, patterns of treatment discontinuation, and dose adjustments.

RESULTS

Thirty-six physicians contributed charts from 433 mRCC patients. Seventy-seven percent of patients received a VEGF inhibitor as first targeted therapy; 23% received an mTOR inhibitor. Among first-line VEGF users, second-line treatments were 66% mTOR and 34% VEGF inhibitors. Among first-line mTOR users, second-line treatments were 94% VEGF and 6% mTOR inhibitors. Sunitinib followed by everolimus was the most commonly used treatment sequence. Estimated median duration for second targeted therapy was 8.6 months, and median overall survival (OS) and progression-free survival (PFS) were 27.4 and 10.8 months, respectively. Efficacy, treatment guidelines and mechanism of action were the most important considerations for treatment choice.

LIMITATIONS

LIMITATIONS include no adjustment for baseline characteristics, possible difference between physician-defined progression and central review in the clinical trial setting, and limited data availability for axitinib during the study period.

CONCLUSION

In this large retrospective chart review among community oncologists, VEGF-mTOR-VEGF was the most common treatment sequence for mRCC. The most common drugs were sunitinib in the first line and everolimus in the second line.

Comparative outcomes of everolimus, temsirolimus and sorafenib as second targeted therapies for metastatic renal cell carcinoma: a US medical record review

OBJECTIVE

To compare outcomes of metastatic renal cell carcinoma (mRCC) patients treated with everolimus, temsirolimus, and sorafenib following initial treatment with a tyrosine kinase inhibitor (TKI) in community and academic practices throughout the US.

RESEARCH DESIGN AND METHODS

Medical records of mRCC patients who received everolimus, temsirolimus or sorafenib as their second therapy following a TKI were retrospectively reviewed from a nationally representative panel of oncologists. Overall survival (OS) and progression-free survival (PFS) of second targeted therapies were compared using multivariable Cox proportional hazard models, with adjustment for demographics, disease severity and prior treatments.

RESULTS

A total of 233, 178, and 123 mRCC patients receiving everolimus, temsirolimus, and sorafenib, respectively, as second targeted therapies were included. Eighty-six percent used sunitinib and the remainder used sorafenib or pazopanib as their initial TKI. After adjusting for baseline characteristics, everolimus was associated with significantly prolonged OS (hazard ratio [HR] 0.60; CI 0.42-0.85; p = 0.004) and PFS (HR 0.73; CI 0.54-0.97; p = 0.032) compared to temsirolimus. Everolimus was associated with significantly longer OS (HR 0.66; CI 0.44-0.99; p = 0.045) and numerically longer PFS compared to sorafenib. No significant differences were observed between temsirolimus and sorafenib.

LIMITATIONS

Despite adjustment for multiple patient characteristics, comparisons between treatment groups may be confounded by unobserved factors in this retrospective observational study. Tolerability outcomes were not collected.

CONCLUSIONS

In this retrospective, non-randomized study of mRCC patients with prior TKI treatment, everolimus was associated with significantly prolonged OS and PFS compared to temsirolimus and significantly prolonged OS compared to sorafenib.

Small molecule targeted therapies for the second-line treatment for metastatic renal cell carcinoma: a systematic review and indirect comparison of safety and efficacy

BACKGROUND

Patients with metastatic renal cell carcinoma (mRCC) and a good performance status typically receive an anti-vascular endothelial growth factor receptor (VEGFR) TKI (sunitinib or pazopanib) as initial therapy. Upon disease progression or intolerance, there are four orally administered agents approved in the second-line setting (including cytokine-refractory). However, head-to-head comparative trial data are limited. In this study, an indirect statistical comparison of safety and efficacy was undertaken between axitinib, sorafenib, pazopanib and everolimus in second-line therapy mRCC.

METHODS

A systematic review of major databases was conducted from January 2005 to June 2013 for randomized controlled trials (RCTs) evaluating at least one of the four agents in second-line mRCC. Bayesian mixed treatment comparison models were fitted to assess relative effectiveness on multiple endpoints such as objective response rates, dose-limiting grade III/IV toxicities, treatment discontinuations and progression-free survival (PFS).

RESULTS

Four RCTs met the inclusion criteria. All four agents seem able to induce tumor shrinkage and to provide patients with a clinically meaningful PFS benefit. Axitinib was superior to pazopanib [hazard ratio (HR) 0.64; 95 % credible interval (95 % Crl) 0.42-0.96] and sorafenib (HR 0.70; 95 % Crl 0.57-0.87) in terms of PFS. However, axitinib was associated with an elevated risk of fatigue and to a lesser extent stomatitis.

CONCLUSIONS

Keeping in mind the caveats associated with cross-trial statistical comparisons, axitinib provides superior PFS relative to pazopanib and sorafenib. Everolimus, an mammalian target of rapamycin inhibitor, is mechanistically distinct from the other agents and remains a useful option for patient's post-anti-VEGFR TKI failure.

Second-line treatments for the management of advanced renal cell carcinoma: systematic review and meta-analysis

OBJECTIVES

A systematic review/meta-analysis was conducted to assess the effectiveness and safety of second-line treatments for advanced renal cell carcinoma (RCC), which includes the vascular endothelial growth factor inhibitor axitinib.

METHODS

Database searches were conducted to identify randomised controlled trials (RCTs). Indirect comparisons using a fixed-effect Bayesian model were used to assess the relative effectiveness of treatments and reported as hazard ratio (HR) and 95% credible intervals (CrI).

RESULTS

Although 24 RCTs met eligibility criteria, only three studies were included in the fixed-effect Bayesian meta-analysis, due to differences in patient inclusion criteria/reported outcomes in the wider dataset. Robust meta-analysis was restricted to the subgroup pretreated with cytokines. In terms of progression-free survival (PFS), axitinib was superior compared with placebo (HR = 0.25, 95% CrI: 0.17 - 0.38), sorafenib (HR = 0.46, 95% CrI: 0.32 - 0.68) and pazopanib (HR = 0.47, 95% CrI: 0.26 - 0.85). An analysis including all patients, regardless of previous first-line treatment, reported similar results. There was no significant difference in PFS between sorafenib and pazopanib.

CONCLUSION

Results from the present study suggest that axitinib will be an important treatment option to extend PFS in the management of advanced RCC in the second-line setting. Ongoing research will define the optimal treatment algorithm leading to a patient-focused treatment strategy.