Gideon Michael Blumenthal

Pathological complete response and long-term clinical benefit in breast cancer: the CTNeoBC pooled analysis

BACKGROUNDnPathological complete response has been proposed as a surrogate endpoint for prediction of long-term clinical benefit, such as disease-free survival, event-free survival (EFS), and overall survival (OS). We had four key objectives: to establish the association between pathological complete response and EFS and OS, to establish the definition of pathological complete response that correlates best with long-term outcome, to identify the breast cancer subtypes in which pathological complete response is best correlated with long-term outcome, and to assess whether an increase in frequency of pathological complete response between treatment groups predicts improved EFS and OS.nnnMETHODSnWe searched PubMed, Embase, and Medline for clinical trials of neoadjuvant treatment of breast cancer. To be eligible, studies had to meet three inclusion criteria: include at least 200 patients with primary breast cancer treated with preoperative chemotherapy followed by surgery; have available data for pathological complete response, EFS, and OS; and have a median follow-up of at least 3 years. We compared the three most commonly used definitions of pathological complete response--ypT0 ypN0, ypT0/is ypN0, and ypT0/is--for their association with EFS and OS in a responder analysis. We assessed the association between pathological complete response and EFS and OS in various subgroups. Finally, we did a trial-level analysis to assess whether pathological complete response could be used as a surrogate endpoint for EFS or OS.nnnFINDINGSnWe obtained data from 12 identified international trials and 11u2008955 patients were included in our responder analysis. Eradication of tumour from both breast and lymph nodes (ypT0 ypN0 or ypT0/is ypN0) was better associated with improved EFS (ypT0 ypN0: hazard ratio [HR] 0·44, 95% CI 0·39-0·51; ypT0/is ypN0: 0·48, 0·43-0·54) and OS (0·36, 0·30-0·44; 0·36, 0·31-0·42) than was tumour eradication from the breast alone (ypT0/is; EFS: HR 0·60, 95% CI 0·55-0·66; OS 0·51, 0·45-0·58). We used the ypT0/is ypN0 definition for all subsequent analyses. The association between pathological complete response and long-term outcomes was strongest in patients with triple-negative breast cancer (EFS: HR 0·24, 95% CI 0·18-0·33; OS: 0·16, 0·11-0·25) and in those with HER2-positive, hormone-receptor-negative tumours who received trastuzumab (EFS: 0·15, 0·09-0·27; OS: 0·08, 0·03, 0·22). In the trial-level analysis, we recorded little association between increases in frequency of pathological complete response and EFS (R(2)=0·03, 95% CI 0·00-0·25) and OS (R(2)=0·24, 0·00-0·70).nnnINTERPRETATIONnPatients who attain pathological complete response defined as ypT0 ypN0 or ypT0/is ypN0 have improved survival. The prognostic value is greatest in aggressive tumour subtypes. Our pooled analysis could not validate pathological complete response as a surrogate endpoint for improved EFS and OS.nnnFUNDINGnUS Food and Drug Administration.

Lung Master Protocol (Lung-MAP)-A Biomarker-Driven Protocol for Accelerating Development of Therapies for Squamous Cell Lung Cancer: SWOG S1400

The Lung Master Protocol (Lung-MAP, S1400) is a groundbreaking clinical trial designed to advance the efficient development of targeted therapies for squamous cell carcinoma (SCC) of the lung. There are no approved targeted therapies specific to advanced lung SCC, although The Cancer Genome Atlas project and similar studies have detected a significant number of somatic gene mutations/amplifications in lung SCC, some of which are targetable by investigational agents. However, the frequency of these changes is low (5%–20%), making recruitment and study conduct challenging in the traditional clinical trial setting. Here, we describe our approach to development of a biomarker-driven phase II/II multisubstudy “Master Protocol,” using a common platform (next-generation DNA sequencing) to identify actionable molecular abnormalities, followed by randomization to the relevant targeted therapy versus standard of care. Clin Cancer Res; 21(7); 1514–24. ©2015 AACR.

FDA Approval: Alectinib for the Treatment of Metastatic, ALK-Positive Non–Small Cell Lung Cancer Following Crizotinib

On December 11, 2015, the FDA granted accelerated approval to alectinib (Alecensa; Genentech) for the treatment of patients with anaplastic lymphoma receptor tyrosine kinase (ALK)-positive, metastatic non–small cell lung cancer (NSCLC) who have progressed on or are intolerant to crizotinib. This approval was based on two single-arm trials including 225 patients treated with alectinib 600 mg orally twice daily. The objective response rates (ORR) by an independent review committee in these studies were 38% [95% confidence interval (CI), 28–49] and 44% (95% CI, 36–53); the median durations of response (DOR) were 7.5 months and 11.2 months. In a pooled analysis of 51 patients with measurable disease in the central nervous system (CNS) at baseline, the CNS ORR was 61% (95% CI, 46–74); the CNS DOR was 9.1 months. The primary safety analysis population included 253 patients. The most common adverse reactions were fatigue (41%), constipation (34%), edema (30%), and myalgia (29%). The most common laboratory abnormalities were anemia (56%), increased aspartate aminotransferase (51%), increased alkaline phosphatase (47%), increased creatine phosphokinase (43%), hyperbilirubinemia (39%), hyperglycemia (36%), increased alanine aminotransferase (34%), and hypocalcemia (32%). Dose reductions due to adverse reactions occurred in 12% of patients, whereas 27% of patients had alectinib dosing interrupted for adverse reactions. Permanent discontinuation of alectinib due to adverse reactions occurred in only 6% of patients. With the clinically meaningful ORR and DOR as well as the safety profile observed in these trials, alectinib was determined to have a favorable benefit–risk profile for the treatment of the indicated population. Clin Cancer Res; 22(21); 5171–6. ©2016 AACR.

The role of nonrandomized trials in the evaluation of oncology drugs

Although randomized trials provide the most reliable evidence of a drugs safety and efficacy, there are situations where randomized trials are not possible or ethical. In this article we discuss when and how single‐arm trials can be used to support full approval of oncology drugs. These include situations in which an unprecedented effect on tumor response is observed in a setting of high unmet medical need, clinical trial patients have been well characterized, enabling a target population to be clearly defined, experience exists in a sufficient number of patients to allow adequate assessment of the risk:benefit relationship, and a proper historical context can be provided for analysis. We also discuss how response rates might be considered predictive of long‐term outcomes or clinically meaningful in and of themselves in certain contexts.

FDA Approval Summary: Pembrolizumab for Treatment of Metastatic Non‐Small Cell Lung Cancer: First‐Line Therapy and Beyond

This FDA approval summary provides an update on approval of pembrolizumab for treatment of patients with metastatic non‐small cell lung cancer whose tumors express PD‐L1 as determined by an FDA‐approved test. The results of KEYNOTE‐010 and KEYNOTE‐024 trials are presented.

Overestimation of the Effect Size in Group Sequential Trials

Group sequential designs (GSD), which provide for interim monitoring of efficacy data and allow potential early trial termination while preserving the type I error rate, have become commonplace in oncology clinical trials. Although ethically appealing, GSDs tend to overestimate the true treatment effect size at early interim analyses. Overestimation of the treatment effect may exaggerate the benefit of a drug and provide imprecise information for physicians and their patients about a drugs true effect. The cause and effect of such a phenomenon are generally not well understood by many in clinical trial practice. In this article, we provide a graphical explanation for why the phenomenon of overestimation in GSDs occurs. The potential overestimation of the magnitude of the treatment effect is of particular concern in oncology, in which the more subjective endpoint of progression-free survival has increasingly been adopted as the primary endpoint in pivotal phase III trials. Clin Cancer Res; 18(18); 4872–6. ©2012 AACR.

Real-world Data for Clinical Evidence Generation in Oncology

Conventional cancer clinical trials can be slow and costly, often produce results with limited external validity, and are difficult for patients to participate in. Recent technological advances and a dynamic policy landscape in the United States have created a fertile ground for the use of real-world data (RWD) to improve current methods of clinical evidence generation. Sources of RWD include electronic health records, insurance claims, patient registries, and digital health solutions outside of conventional clinical trials. A definition focused on the original intent of data collected at the point of care can distinguish RWD from conventional clinical trial data. When the intent of data collection at the point of care is research, RWD can be generated using experimental designs similar to those employed in conventional clinical trials, but with several advantages that include gains in efficient execution of studies with an appropriate balance between internal and external validity. RWD can support active pharmacovigilance, insights into the natural history of disease, and the development of external control arms. Prospective collection of RWD can enable evidence generation based on pragmatic clinical trials (PCTs) that support randomized study designs and expand clinical research to the point of care. PCTs may help address the growing demands for access to experimental therapies while increasing patient participation in cancer clinical trials. Conducting valid real-world studies requires data quality assurance through auditable data abstraction methods and new incentives to drive electronic capture of clinically relevant data at the point of care.

Assessment of benefits and risks in development of targeted therapies for cancer--The view of regulatory authorities.

Drug licensing and approval decisions involve the balancing of benefits against the risks (harms) in the presence of uncertainty. Typically, the benefits are estimated from primary efficacy endpoints from confirmatory (phase III) clinical trials although exceptions where promising early data from single‐arm studies have led to accelerated approvals are not uncommon, particularly for cancer drugs.

Time dependent pharmacokinetics of pembrolizumab in patients with solid tumor and its correlation with best overall response

Pembrolizumab is a monoclonal antibody that targets the programmed death-1 receptor to induce immune-mediated clearance (CL) of tumor cells. Originally approved by the US Food and Drug Administration in 2014 for treating patients with unresectable or metastatic melanoma, pembrolizumab is now also used to treat patients with non-small-cell lung cancer, classical Hodgkin lymphoma, head and neck cancer, and urothelial cancer. This paper describes the recently identified feature of pembrolizumab pharmacokinetics, the time-dependent or time-varying CL. Overall results indicate that CL decreases over the treatment period of a typical patient in a pattern well described by a sigmoidal function of time with three parameters: the maximum proportion change in CL from baseline (approximately Imax or exactly eImaxxa0−xa01), the time to reach Imax/2 (TI50), and a Hill coefficient. Best overall response per response evaluation criteria in solid tumor category was found to be associated with the magnitude of Imax.

Exploratory analysis of the association of depth of response and survival in patients with metastatic non-small-cell lung cancer treated with a targeted therapy or immunotherapy

BACKGROUNDnResponse Evaluation Criteria in Solid Tumors (RECIST) permits rapid evaluation of new therapeutic strategies in cancer. However, RECIST does not capture the heterogeneity of response in highly active therapies. Depth of tumor response may provide a more granular view of response. We explored the association between, depth of response (DepOR), with overall survival (OS) and progression-free survival (PFS) for patients with NSCLC being treated with an ALK inhibitor (ALKi) or an anti-PD-1 antibody (Ab).nnnMETHODSnExperimental arms from two randomized controlled trials (RCTs) of an ALKi and two RCTs of an anti-PD-1 Ab were separately pooled. Patient responses were grouped into DepOR quartiles by percentage of maximal tumor shrinkage (Q1=1%-25%, Q2=26%-50%, Q3=51%-75%, and Q4=76%-100%), Q0 had no shrinkage. We carried out a retrospective exploratory responder analysis to evaluate the association between DepOR and OS or PFS using hazard ratios (HR) generated by the Cox proportional hazards model.nnnRESULTSnIn the pooled ALK analysis there were 12, 39, 70, 144, and 40 patients in quartiles 0-4, respectively. The DepOR versus PFS/OS analyses HR were: 0.19/0.94 for Q10.11/0.56 for Q2, 0.05/0.28 for Q3, and 0.03/0.05 for Q4. In the PD-1 trials within quartiles 0-4 there were 168, 70, 44, 45, and 28 patients, respectively. The DepOR versus PFS/OS analyses HR were 0.3/0.52 for Q1, 0.22/0.47 for Q2, 0.09/0.07 for Q3, and 0.07/0.14 for Q4.nnnCONCLUSIONSnOur analysis suggests a greater DepOR is associated with longer PFS and OS for patients receiving ALKi or anti-PD1 Ab. Overall, this suggests that DepOR may provide an additional outcome measure for clinical trials, and may allow better comparisons of treatment activity.BACKGROUNDnResponse Evaluation Criteria in Solid Tumors (RECIST) permits rapid evaluation of new therapeutic strategies in cancer. However, RECIST does not capture the heterogeneity of response in highly active therapies. Depth of tumor response may provide a more granular view of response. We explored the association between, depth of response (DepOR), with overall survival (OS) and progression-free survival (PFS) for patients with NSCLC being treated with an ALK inhibitor (ALKi) or an anti-PD-1 antibody (Ab).nnnMETHODSnExperimental arms from two randomized controlled trials (RCTs) of an ALKi and two RCTs of an anti-PD-1 Ab were separately pooled. Patient responses were grouped into DepOR quartiles by percentage of maximal tumor shrinkage (Q1=1%-25%, Q2=26%-50%, Q3=51%-75%, and Q4=76%-100%), Q0 had no shrinkage. We carried out a retrospective exploratory responder analysis to evaluate the association between DepOR and OS or PFS using hazard ratios (HR) generated by the Cox proportional hazards model.nnnRESULTSnIn the pooled ALK analysis there were 12, 39, 70, 144, and 40 patients in quartiles 0-4, respectively. The DepOR versus PFS/OS analyses HR were: 0.19/0.94 for Q10.11/0.56 for Q2, 0.05/0.28 for Q3, and 0.03/0.05 for Q4. In the PD-1 trials within quartiles 0-4 there were 168, 70, 44, 45, and 28 patients, respectively. The DepOR versus PFS/OS analyses HR were 0.3/0.52 for Q1, 0.22/0.47 for Q2, 0.09/0.07 for Q3, and 0.07/0.14 for Q4.nnnCONCLUSIONSnOur analysis suggests a greater DepOR is associated with longer PFS and OS for patients receiving ALKi or anti-PD1 Ab. Overall, this suggests that DepOR may provide an additional outcome measure for clinical trials, and may allow better comparisons of treatment activity.BackgroundnResponse Evaluation Criteria in Solid Tumors (RECIST) permits rapid evaluation of new therapeutic strategies in cancer. However, RECIST does not capture the heterogeneity of response in highly active therapies. Depth of tumor response may provide a more granular view of response. We explored the association between, depth of response (DepOR), with overall survival (OS) and progression-free survival (PFS) for patients with NSCLC being treated with an ALK inhibitor (ALKi) or an anti-PD-1 antibody (Ab).nnnMethodsnExperimental arms from two randomized controlled trials (RCTs) of an ALKi and two RCTs of an anti-PD-1 Ab were separately pooled. Patient responses were grouped into DepOR quartiles by percentage of maximal tumor shrinkage (Q1u2009=u20091%-25%, Q2u2009=u200926%-50%, Q3u2009=u200951%-75%, and Q4u2009=u200976%-100%), Q0 had no shrinkage. We carried out a retrospective exploratory responder analysis to evaluate the association between DepOR and OS or PFS using hazard ratios (HR) generated by the Cox proportional hazards model.nnnResultsnIn the pooled ALK analysis there were 12, 39, 70, 144, and 40 patients in quartiles 0-4, respectively. The DepOR versus PFS/OS analyses HR were: 0.19/0.94 for Q1u20090.11/0.56 for Q2, 0.05/0.28 for Q3, and 0.03/0.05 for Q4. In the PD-1 trials within quartiles 0-4 there were 168, 70, 44, 45, and 28 patients, respectively. The DepOR versus PFS/OS analyses HR were 0.3/0.52 for Q1, 0.22/0.47 for Q2, 0.09/0.07 for Q3, and 0.07/0.14 for Q4.nnnConclusionsnOur analysis suggests a greater DepOR is associated with longer PFS and OS for patients receiving ALKi or anti-PD1 Ab. Overall, this suggests that DepOR may provide an additional outcome measure for clinical trials, and may allow better comparisons of treatment activity.BACKGROUNDnResponse Evaluation Criteria in Solid Tumors (RECIST) permits rapid evaluation of new therapeutic strategies in cancer. However, RECIST does not capture the heterogeneity of response in highly active therapies. Depth of tumor response may provide a more granular view of response. We explored the association between, depth of response (DepOR), with overall survival (OS) and progression-free survival (PFS) for patients with NSCLC being treated with an ALK inhibitor (ALKi) or an anti-PD-1 antibody (Ab).nnnMETHODSnExperimental arms from two randomized controlled trials (RCTs) of an ALKi and two RCTs of an anti-PD-1 Ab were separately pooled. Patient responses were grouped into DepOR quartiles by percentage of maximal tumor shrinkage (Q1=1%-25%, Q2=26%-50%, Q3=51%-75%, and Q4=76%-100%), Q0 had no shrinkage. We carried out a retrospective exploratory responder analysis to evaluate the association between DepOR and OS or PFS using hazard ratios (HR) generated by the Cox proportional hazards model.nnnRESULTSnIn the pooled ALK analysis there were 12, 39, 70, 144, and 40 patients in quartiles 0-4, respectively. The DepOR versus PFS/OS analyses HR were: 0.19/0.94 for Q10.11/0.56 for Q2, 0.05/0.28 for Q3, and 0.03/0.05 for Q4. In the PD-1 trials within quartiles 0-4 there were 168, 70, 44, 45, and 28 patients, respectively. The DepOR versus PFS/OS analyses HR were 0.3/0.52 for Q1, 0.22/0.47 for Q2, 0.09/0.07 for Q3, and 0.07/0.14 for Q4.nnnCONCLUSIONSnOur analysis suggests a greater DepOR is associated with longer PFS and OS for patients receiving ALKi or anti-PD1 Ab. Overall, this suggests that DepOR may provide an additional outcome measure for clinical trials, and may allow better comparisons of treatment activity.