With the approval of immunotherapies for a variety of indications, methods to assess treatment benefit addressing the response patterns observed are important. We evaluated RECIST criteria-based ...overall response rate (ORR) and progression-free survival (PFS) as potential surrogate endpoints of overall survival (OS), and explored a modified definition of PFS by altering the threshold percentage determining disease progression to assess the association with survival benefit in immunotherapy trials.
Thirteen randomized, multicenter, active-control trials containing immunotherapeutic agents submitted to the FDA were analyzed. Associations between treatment effects of ORR, PFS, modified PFS, and OS were evaluated at individual and trial levels. Patient-level responder analysis was performed for PFS and OS.
The coefficient of determination (
²) measured the strength of associations, where values near 1 imply surrogacy and values close to 0 suggest no association. At the trial level, the association between hazard ratios (HR) of PFS and OS was
= 0.1303, and between the odds ratio (OR) of ORR and HR of OS was
= 0.1277. At the individual level, the Spearman rank correlation coefficient between PFS and OS was 0.61. Trial-level associations between modified PFS and OS ranged between 0.07 and 0.1, and individual-level correlations were approximately 0.6. HRs of PFS and OS for responders versus nonresponders were 0.129 95% confidence interval (CI), 0.11-0.15 and 0.118 (95% CI, 0.11-0.13), respectively.
Although responders exhibited longer survival and PFS than nonresponders, the trial-level and individual-level associations were weak between PFS/ORR and OS. Modifications to PFS did not improve associations.
.
Clinical trial eligibility criteria are necessary to define the patient population under study and improve trial safety. However, there are concerns that eligibility criteria for cancer clinical ...trials are too restrictive and limit patient enrollment in clinical trials. Recently, there have been initiatives to re-examine and modernize eligibility criteria for oncology clinical trials. To assess current eligibility requirements for cancer clinical trials, we have conducted a comprehensive review of eligibility criteria for commercial investigational new drug clinical trial applications submitted to the US Food and Drug Administration Office of Hematology and Oncology Products in 2015. Our findings suggest that eligibility criteria for current cancer clinical trials tend to narrowly define the study population and limit the study to lower-risk patients, which may not be reflective of the greater patient population outside of the study. We discuss potential areas for expanding eligibility criteria to include more patients in clinical trials and design options for clinical trials incorporating expanded eligibility criteria. The broadening of clinical trial eligibility criteria can be considered to better reflect the real-world patient population, improve clinical trial participation, and increase patient access to new investigational treatments.
On December 22, 2014, the FDA granted accelerated approval to nivolumab (OPDIVO; Bristol-Myers Squibb) for the treatment of patients with unresectable or metastatic melanoma and disease progression ...following ipilimumab and, if BRAF V600 mutation positive, a BRAF inhibitor. Approval was based on a clinically meaningful, durable objective response rate (ORR) in a non-comparative analysis of 120 patients who received 3 mg/kg of nivolumab intravenously every 2 weeks with at least 6-month follow-up in an ongoing, randomized, open-label, active-controlled clinical trial. The ORR as assessed by a blinded independent review committee per RECIST v1.1 was 31.7% (95% confidence interval, 23.5-40.8). Ongoing responses were observed in 87% of responding patients, ranging from 2.6+ to 10+ months. In 13 patients, the response duration was 6 months or longer. The risks of nivolumab, including clinically significant immune-mediated adverse reactions (imARs), were assessed in 268 patients who received at least one dose of nivolumab. The FDA review considered whether the ORR and durations of responses were reasonably likely to predict clinical benefit, the adequacy of the safety database, and systematic approaches to the identification, description, and patient management for imARs in product labeling.
.
Cancer clinical trials have relied on overall survival and measures of tumor growth or reduction to assess the efficacy of a drug. However, benefits are often accompanied by significant symptomatic ...toxicities. The degree to which a therapy improves disease symptoms and introduces symptomatic toxicity affects how patients function in their daily lives. These concepts are important contributors to health-related quality of life (HRQOL). In this article, we discuss patient-reported outcome (PRO) assessment in cancer trials and challenges relying solely on static multi-item HRQOL instruments. We propose focusing on three separate measures of well-defined concepts: symptomatic adverse events, physical function, and disease-related symptoms, which are key contributors to the effect of a therapy on HRQOL. Separate measures of these three concepts may facilitate the incorporation of emerging contemporary instruments that can tailor the PRO assessment strategy to different trial contexts. Irrespective of the PRO measures used, continued improvement in trial design and conduct is crucial to decrease missing data and optimize the quality of PRO information. International stakeholder collaboration and continued research into optimal practices for PRO and other clinical outcome assessments are necessary to advance a common framework for generating and reporting rigorous patient-centered data from cancer clinical trials.
Purpose The primary purposes of eligibility criteria are to protect the safety of trial participants and define the trial population. Excessive or overly restrictive eligibility criteria can slow ...trial accrual, jeopardize the generalizability of results, and limit understanding of the intervention's benefit-risk profile. Methods ASCO, Friends of Cancer Research, and the US Food and Drug Administration examined specific eligibility criteria (ie, brain metastases, minimum age, HIV infection, and organ dysfunction and prior and concurrent malignancies) to determine whether to modify definitions to extend trials to a broader population. Working groups developed consensus recommendations based on review of evidence, consideration of the patient population, and consultation with the research community. Results Patients with treated or clinically stable brain metastases should be routinely included in trials and only excluded if there is compelling rationale. In initial dose-finding trials, pediatric-specific cohorts should be included based on strong scientific rationale for benefit. Later phase trials in diseases that span adult and pediatric populations should include patients older than age 12 years. HIV-infected patients who are healthy and have low risk of AIDS-related outcomes should be included absent specific rationale for exclusion. Renal function criteria should enable liberal creatinine clearance, unless the investigational agent involves renal excretion. Patients with prior or concurrent malignancies should be included, especially when the risk of the malignancy interfering with either safety or efficacy endpoints is very low. Conclusion To maximize generalizability of results, trial enrollment criteria should strive for inclusiveness. Rationale for excluding patients should be clearly articulated and reflect expected toxicities associated with the therapy under investigation.
Both objective response rate (ORR) and progression-free survival as defined by RECIST are weakly associated with overall survival (OS) in trials evaluating immunotherapy drug products. We proposed a ...novel intermediate response endpoint (IME) for evaluating immunotherapies.
We defined IME response as having no nontarget lesion progression, no new lesion appearance, and reaching a target lesion response determined by baseline tumor burden, tumor reduction depth, and tumor change dynamics within one year after randomization. Database used consisted of data from randomized active-controlled immunotherapy trials. Criterion for IME was developed on the basis of patient-level data from a training dataset, and further evaluated using an independent testing dataset. A patient-level responder analysis comparing OS between patients with and without an IME response was conducted using combined data. Association between trial-level OS hazard ratio (HR) and IME odds ratio (OR) was analyzed using a weighted linear regression model.
A total of 5,806 patients from 9 randomized studies were included in the database. At patient level, patients with IME response had improved OS compared with nonresponders (HR = 0.09). At trial level, association between OS and IME was moderate (
= 0.68).
The IME was moderately associated with OS, and the association appeared to be stronger than the association observed between RECIST-defined ORR and OS. However, the analyses conducted in this research are exploratory and further evaluation is needed before using this endpoint in future studies.
.
Cancer therapeutics frequently lead to symptomatic adverse events (AE) that can affect treatment tolerability. The NCI has developed the Patient-Reported Outcomes version of the Common Terminology ...Criteria for Adverse Events (PRO-CTCAE) to assess symptomatic AEs by direct patient self-report. Although longitudinal assessment of patient-reported symptomatic AEs holds promise to better inform treatment tolerability, using patient-reported outcome (PRO) measures to assess symptomatic AEs has raised several regulatory and good clinical practice issues among those who conduct cancer clinical trials. These include concerns regarding trial monitoring, clinical review of PRO results by investigators and delegated clinical staff, whether PRO data on symptomatic AEs require investigational new drug (IND) safety reporting, and how the trial conduct and resultant PRO data will be assessed during clinical investigator site inspections. This article addresses current thinking regarding these issues in cancer clinical trials from the FDA, the NCI, and the Office for Human Research Protections. PRO measures, such as PRO-CTCAE, that assess symptomatic AEs in cancer trials are considered similar to other PRO assessments of symptoms, function, and health-related quality of life and can generate complementary data that may inform tolerability. Clarity on operational concerns related to incorporating PRO measures to inform tolerability is critical to continue the advancement of rigorous PRO assessment in cancer clinical trials.
.
On December 19, 2016, the FDA granted accelerated approval to rucaparib (RUBRACA; Clovis Oncology, Inc.) for the treatment of patients with deleterious
mutation (germline and/or somatic)-associated ...advanced ovarian cancer who have been treated with two or more chemotherapies. The FDA also approved the FoundationFocus CDx
test (Foundation Medicine, Inc.), the first next-generation sequencing-based companion diagnostic, for identifying patients with advanced ovarian cancer eligible for treatment with rucaparib based on detection of deleterious
and/or
mutations in tumor tissue. Rucaparib's approval was based primarily on efficacy data from 106 patients with
mutation-associated ovarian cancer who had prior treatment with two or more chemotherapies and safety data from 377 patients with ovarian cancer treated with rucaparib 600 mg orally twice daily on two open-label, single-arm trials. Investigator-assessed objective response rate was 54% 57/106; 95% confidence interval (CI), 44-64, and median duration of response was 9.2 months (95% CI, 6.6-11.7). The approved companion diagnostic verified tumor
mutation status retrospectively in 96% (64/67) of patients. Common adverse reactions (≥20%) to rucaparib were nausea, fatigue, vomiting, anemia, abdominal pain, dysgeusia, constipation, decreased appetite, diarrhea, thrombocytopenia, and dyspnea. This article summarizes the FDA review and data supporting rucaparib's accelerated approval.
.