Contemporary Approach to The Diagnosis and Classification of Myelodysplastic Neoplasms/Syndromes- Recommendations from The International Consortium for MDS (icMDS)

Myelodysplastic neoplasms/syndromes (MDS) are a heterogeneous group of biologically distinct entities characterized by variable degrees of ineffective hematopoiesis. Recently, two classification systems (the 5th edition of the WHO Classification and the International Consensus Classification) further sub-characterized MDS into morphologic and genetically defined groups. Accurate diagnosis and subclassification of MDS require a multistep systemic approach. The International Consortium for MDS (icMDS) summarizes a contemporary, practical, and multimodal approach to MDS diagnosis and classification.

Randomized study of induction with bendamustine-rituximab ± bortezomib and maintenance with rituximab ± lenalidomide for MCL

ABSTRACT

Although initial therapy of mantle cell lymphoma (MCL) is not standardized, bendamustine plus rituximab (BR) is commonly used in older patients. Rituximab (R) maintenance after induction is often used. Thus, the open-label, randomized phase 2 ECOG-ACRIN Cancer Research Group E1411 trial was designed to test 2 questions: (1) does addition of bortezomib to BR induction (BVR) and/or (2) addition of lenalidomide to rituximab (LR) maintenance improve progression-free survival (PFS) in patients with treatment-naïve MCL? From 2012 to 2016, 373 previously untreated patients, 87% aged ≥60 years, were enrolled in this trial. At a median follow-up of 7.5 years, there is no difference in the median PFS of BR compared with BVR (5.5 vs 6.4 years; hazard ratio [HR], 0.90; 90% confidence interval [CI], 0.70-1.16). There were no unexpected additional toxicities with BVR treatment compared with BR, with no impact on total dose/duration of treatment received. Independent of the induction treatment, addition of lenalidomide did not significantly improve PFS, with median PFS in R vs LR (5.9 vs 7.2 years; HR, 0.84; 90% CI, 0.62-1.15). Most patients completed the planned 24 cycles of LR at the scheduled dose. In summary, adding bortezomib to BR induction does not prolong PFS in treatment-naïve MCL, and LR maintenance was not associated with longer PFS compared with R alone after BR. Nonetheless, the >5-year median PFS outcomes in this prospective cooperative group trial indicate the efficacy of BR followed by R maintenance as highly effective initial therapy for older patients with MCL. This trial was registered at www.clinicaltrials.gov as #NCT01415752.

Blinatumomab for MRD-Negative Acute Lymphoblastic Leukemia in Adults

BACKGROUND

Many older adults with B-cell precursor acute lymphoblastic leukemia (BCP-ALL) have a relapse despite having a measurable residual disease (MRD)-negative complete remission with combination chemotherapy. The addition of blinatumomab, a bispecific T-cell engager molecule that is approved for the treatment of relapsed, refractory, and MRD-positive BCP-ALL, may have efficacy in patients with MRD-negative remission.

METHODS

In a phase 3 trial, we randomly assigned patients 30 to 70 years of age with BCR::ABL1-negative BCP-ALL (with :: indicating fusion) who had MRD-negative remission (defined as <0.01% leukemic cells in bone marrow as assessed on flow cytometry) after induction and intensification chemotherapy to receive four cycles of blinatumomab in addition to four cycles of consolidation chemotherapy or to receive four cycles of consolidation chemotherapy alone. The primary end point was overall survival, and relapse-free survival was a secondary end point.

RESULTS

The data and safety monitoring committee reviewed the results from the third efficacy interim analysis and recommended that they be reported. Complete remission with or without full count recovery was observed in 395 of 488 enrolled patients (81%). Of the 224 patients with MRD-negative status, 112 were assigned to each group. The characteristics of the patients were balanced between the groups. At a median follow-up of 43 months, an advantage was observed in the blinatumomab group as compared with the chemotherapy-only group with regard to overall survival (at 3 years: 85% vs. 68%; hazard ratio for death, 0.41; 95% confidence interval [CI], 0.23 to 0.73; P = 0.002), and the 3-year relapse-free survival was 80% with blinatumomab and 64% with chemotherapy alone (hazard ratio for relapse or death, 0.53; 95% CI, 0.32 to 0.87). A higher incidence of neuropsychiatric events was reported in the blinatumomab group than in the chemotherapy-only group.

CONCLUSIONS

The addition of blinatumomab to consolidation chemotherapy in adult patients in MRD-negative remission from BCP-ALL significantly improved overall survival. (Funded by the National Institutes of Health and others; E1910 ClinicalTrials.gov number, NCT02003222.).

Follow-up from the A041202 study shows continued efficacy of ibrutinib regimens for older adults with CLL

ABSTRACT

A041202 (NCT01886872) is a phase 3 study comparing bendamustine plus rituximab (BR) with ibrutinib and the combination of ibrutinib plus rituximab (IR) in previously untreated older patients with chronic lymphocytic leukemia (CLL). The initial results showed that ibrutinib-containing regimens had superior progression-free survival (PFS) and rituximab did not add additional benefits. Here we present an updated analysis. With a median follow-up of 55 months, the median PFS was 44 months (95% confidence interval [CI], 38-54) for BR and not yet reached in either ibrutinib-containing arm. The 48-month PFS estimates were 47%, 76%, and 76% for BR, ibrutinib, and IR, respectively. The benefit of ibrutinib regimens over chemoimmunotherapy was consistent across subgroups of patients defined by TP53 abnormalities, del(11q), complex karyotype, and immunoglobulin heavy chain variable region (IGHV). No significant interaction effects were observed between the treatment arm and del(11q), the complex karyotype, or IGHV. However, a greater difference in PFS was observed among the patients with TP53 abnormalities. There was no difference in the overall survival. Notable adverse events with ibrutinib included atrial fibrillation (afib) and hypertension. Afib was observed in 11 patients (pts) on BR (3%) and 67 pts on ibrutinib (18%). All-grade hypertension was observed in 95 pts on BR (27%) and 263 pts on ibrutinib (55%). These data show that ibrutinib regimens prolong PFS compared with BR for older patients with treatment-naïve CLL. These benefits were observed across subgroups, including high-risk groups. Strikingly, within the ibrutinib arms, there was no inferior PFS for patients with abnormalities in TP53, the highest risk feature observed in CLL. These data continue to demonstrate the efficacy of ibrutinib in treatment-naïve CLL.

Assessment of the safety of nivolumab in people living with HIV with advanced cancer on antiretroviral therapy: the AIDS Malignancy Consortium 095 Study

BACKGROUND

Although immunotherapy has emerged as a therapeutic strategy for many cancers, there are limited studies establishing the safety and efficacy in people living with HIV (PLWH) and cancer.

METHODS

PLWH and solid tumors or Kaposi sarcoma (KS) receiving antiretroviral therapy and a suppressed HIV viral load received nivolumab at 3 mg/kg every 2 weeks, in two dose deescalation cohorts stratified by CD4 count (stratum 1: CD4 count > 200/µL and stratum 2: CD4 count 100-199/µL). An expansion cohort of 24 participants with a CD4 count > 200/µL was then enrolled.

RESULTS

A total of 36 PLWH received nivolumab, including 15 with KS and 21 with a variety of other solid tumors. None of the first 12 participants had dose-limiting toxicity in both CD4 strata, and five patients (14%) overall had grade 3 or higher immune related adverse events. Objective partial response occurred in nine PLWH and cancer (25%), including in six of 15 with KS (40%; 95% CI, 16.3-64.7). The median duration of response was 9.0 months overall and 12.5 months in KS. Responses were observed regardless of PDL1 expression. There were no significant changes in CD4 count or HIV viral load.

CONCLUSIONS

Nivolumab has a safety profile in PLWH similar to HIV-negative subjects with cancer, and also efficacy in KS. Plasma HIV remained suppressed and CD4 counts remained stable during treatment and antiretroviral therapy, indicating no adverse impact on immune function.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02408861.

A multicenter phase Ib trial of the histone deacetylase inhibitor entinostat in combination with pembrolizumab in patients with myelodysplastic syndromes/neoplasms or acute myeloid leukemia refractory to hypomethylating agents

Patients with myelodysplastic syndromes/neoplasms (MDS) or acute myeloid leukemia (AML) with hypomethylating agent failure have a poor prognosis. Myeloid-derived suppressor cells (MDSCs) can contribute to MDS progression and mediate resistance to anti-PD1 therapy. As histone deacetylase inhibitors (HDACi) decrease MDSCs in preclinical models, we conducted an investigator-initiated, NCI-Cancer Therapy Evaluation Program-sponsored, multicenter, dose escalation, and expansion phase Ib trial (NCT02936752) of the HDACi entinostat and the anti-PD1 antibody pembrolizumab. Twenty-eight patients (25 MDS and 3 AML) were enrolled. During dose escalation (n=13 patients), there was one dose-limiting toxicity (DLT) on dose level (DL) 1 (G5 pneumonia/bronchoalveolar hemorrhage) and two DLTs at DL 2 (G3 pharyngeal mucositis and G3 anorexia). Per the 3 + 3 dose escalation design, DL 1 (entinostat 8 mg PO days 1 and 15 + pembrolizumab 200 mg IV day 1 every 21 days) was expanded and another 15 patients were enrolled. Hematologic adverse events (AEs) were common. The most common non-hematologic ≥G3 AEs were infection (32%), hypoxia/respiratory failure (11%), and dyspnea (11%). There were no protocol-defined responses among the 28 patients enrolled. Two patients achieved a marrow complete remission (mCR). Using a systems immunology approach with mass cytometry and machine learning analysis, mCR patients had increased classical monocytes and macrophages but there was no significant change of MDSCs. In conclusion, combining entinostat with pembrolizumab in patients with advanced MDS and AML was associated with limited clinical efficacy and substantial toxicity. Absence of an effect on MDSCs could be a potential explanation for the limited efficacy of this combination. ClinicalTrial.gov Identifier: NCT02936752.

The New NCI Precision Medicine Trials

Basket, umbrella, and platform trial designs (master protocols) have emerged over the last decade to study precision medicine approaches in oncology. First-generation trials like NCI-MATCH (Molecular Analysis for Therapy Choice) have proven the principle that studying targeted therapies on a large scale is feasible both from the laboratory and clinical perspectives. However, single-agent targeted therapies have shown limited ability to control metastatic disease, despite careful matching of drug to target. As such, newer approaches employing combinations of targeted therapy, or targeted therapy with standard therapies, need to be considered. The NCI has recently embarked on three second-generation precision medicine trials to address this need: ComboMATCH, iMATCH, and myeloMATCH. The design of these trials and necessary infrastructure are discussed in the following perspective.

Classification, risk stratification and response assessment in myelodysplastic syndromes/neoplasms (MDS): A state-of-the-art report on behalf of the International Consortium for MDS (icMDS)

The guidelines for classification, prognostication, and response assessment of myelodysplastic syndromes/neoplasms (MDS) have all recently been updated. In this report on behalf of the International Consortium for MDS (icMDS) we summarize these developments. We first critically examine the updated World Health Organization (WHO) classification and the International Consensus Classification (ICC) of MDS. We then compare traditional and molecularly based risk MDS risk assessment tools. Lastly, we discuss limitations of criteria in measuring therapeutic benefit and highlight how the International Working Group (IWG) 2018 and 2023 response criteria addressed these deficiencies and are endorsed by the icMDS. We also address the importance of patient centered care by discussing the value of quality-of-life assessment. We hope that the reader of this review will have a better understanding of how to classify MDS, predict clinical outcomes and evaluate therapeutic outcomes.

The NCI-MATCH trial: lessons for precision oncology

The NCI-MATCH (Molecular Analysis for Therapy Choice) trial ( NCT02465060 ) was launched in 2015 as a genomically driven, signal-seeking precision medicine platform trial-largely for patients with treatment-refractory, malignant solid tumors. Having completed in 2023, it remains one of the largest tumor-agnostic, precision oncology trials undertaken to date. Nearly 6,000 patients underwent screening and molecular testing, with a total of 1,593 patients (inclusive of continued accrual from standard next-generation sequencing) being assigned to one of 38 substudies. Each substudy was a phase 2 trial of a therapy matched to a genomic alteration, with a primary endpoint of objective tumor response by RECIST criteria. In this Perspective, we summarize the outcomes of the initial 27 substudies in NCI-MATCH, which met its signal-seeking objective with 7/27 positive substudies (25.9%). We discuss key aspects of the design and operational conduct of the trial, highlighting important lessons for future precision medicine studies.

Trial Design Considerations to Increase Older Adult Accrual to National Cancer Institute Clinical Trials

Although adults aged 65 years or older make up a strong majority of cancer patients, their underrepresentation in cancer clinical trials leads to the lack of representative data to guide evidence-based therapeutic decisions in this patient population. The Trial Design Working Group, convened as part of the workshop titled, Engaging Older Adults in the National Cancer Institute Clinical Trials Network: Challenges and Opportunities, recommended study designs and design elements that could improve accrual of older adults in National Cancer Institute-funded clinical trials. These include trials that are specifically designed to enroll older adults, trials that include a cohort of older patients (parallel cohort, stratified cohort, or embedded cohort), and trials with pragmatic design elements to facilitate enrollment of older adults. This manuscript provides brief descriptions of the recommended designs, examples of successful trials, and considerations for implementation of these designs. As with any clinical trial, the scientific questions and trial objectives should drive the study design, the selection of endpoints and intervention, and eligibility criteria. When designing trials that include older adults, the heterogeneity of fitness levels is an important consideration as fitness can influence accrual rates and outcomes. Appropriately incorporating geriatric assessments can help identify the optimal subset of older patients for inclusion and minimize selection bias. Incorporating pragmatic design elements to reduce the burden on trial participants as well as on accruing sites and retaining essential elements to ensure that the main goal of the trial can be accomplished can enhance enrollment without compromising the integrity of trials.

Update on Enrollment of Older Adults Onto National Cancer Institute National Clinical Trials Network Trials

BACKGROUND

Older adults are a large and growing proportion of cancer cases in the United States, but concerns persist about whether older adults are adequately represented in the cancer clinical trials that test new options for treatment and cancer care.

METHODS

This paper describes adult patient enrollments by age group to the National Cancer Institute's National Clinical Trials Network (NCTN) from 2016 to 2021, compares patient enrollment by age with the estimated incident cancer population across cancer types, and explores possible associations between patient age and patient race, ethnicity, and sex.

RESULTS

This analysis found that patients aged 18 to 69 years were overrepresented in NCTN trials, whereas patients aged 70 years and older were underrepresented compared with the estimated incident cancer population. Underrepresentation of older patients was seen across cancer types. Older patients who enrolled to NCTN trials were more likely to be non-Hispanic White than the estimated incident cancer population.

CONCLUSIONS

Compared with earlier analyses, NCTN trials are enrolling greater proportions of older adults, primarily driven by higher enrollment among patients aged 65 to 74 years. There is still significant room for improvement, however, especially among patients aged 75 years and older. Additionally, patient demographics should not be viewed in isolation: older Hispanic patients, for instance, were particularly underrepresented among patients enrolled to NCTN trials. The intersection between trial enrollment and age, race, and ethnicity warrants further study so that more targeted enrollment enhancement efforts can be developed that enhance trial diversity across demographic groups.

Integrating Geriatric Assessment Measures into National Cancer Institute Clinical Trials

To improve the care of older adults with cancer, the traditional approach to clinical trial design needs to be reconsidered. Older adults are underrepresented in clinical trials with limited or no information on geriatric-specific factors, such as cognition or comorbidities. To address this knowledge gap and increase relevance of therapeutic clinical trial results to the real-life population, integration of aspects relevant to older adults is needed in oncology clinical trials. Geriatric assessment (GA) is a multidimensional tool comprising validated measures assessing specific health domains that are more frequently affected in older adults, including aspects related to physical function, comorbidity, medication use (polypharmacy), cognitive and psychological status, social support, and nutritional status. There are several mechanisms for incorporating either the full GA or specific GA measures into oncology therapeutic clinical trials to contribute to the overarching goal of the trial. Mechanisms include utilizing GA measures to better characterize the trial population, define trial eligibility, allocate treatment receipt within the context of the trial, develop predictive models for treatment outcomes, guide supportive care strategies, personalize care delivery, and assess longitudinal changes in GA domains. The objective of this manuscript is to review how GA measures can contribute to the overall goal of a clinical trial, to provide a framework to guide the selection and integration of GA measures into clinical trial design, and ultimately enable accrual of older adults to clinical trials by facilitating the design of trials tailored to older adults treated in clinical practice.

Implementing Modernized Eligibility Criteria in US National Cancer Institute Clinical Trials

In 2018, the Cancer Therapy Evaluation Program (CTEP) at the US National Cancer Institute published new protocol template language that focused on organ function and prior and concurrent cancers in an effort to modernize eligibility criteria for cancer treatment trials. We conducted an analysis of CTEP-supported trials to evaluate the uptake and incorporation of the new language. The analysis included evaluation of 122 protocols approved in the years 2018-2020 for inclusion of the modernized eligibility criteria and consistency with new protocol template language related to 7 major eligibility criteria. These were cardiac function, liver function, kidney function, HIV status, prior and/or concurrent malignancies, treated and/or stable brain metastasis, and new and/or progressive brain metastases. Overall, CTEP trials evaluated in this period demonstrated that eligibility criteria were implemented to a relatively high degree ranging from a low of 54.1% for prior and/or concurrent malignancies to a high of 93.4% for eligibility criteria related to HIV infection. The findings demonstrate that modernized eligibility criteria can be successfully implemented but that consistent implementation requires sustained focused effort. As a result of these findings, CTEP began a new initiative in January 2022 that incorporates a specific review of eligibility criteria for new protocols to promote and improve consistency with the modernization effort.

Long-term outcomes for ibrutinib-rituximab and chemoimmunotherapy in CLL: updated results of the E1912 trial

Herein, we present the long-term follow-up of the randomized E1912 trial comparing the long-term efficacy of ibrutinib-rituximab (IR) therapy to fludarabine, cyclophosphamide, and rituximab (FCR) and describe the tolerability of continuous ibrutinib. The E1912 trial enrolled 529 treatment-naïve patients aged ≤70 years with chronic lymphocytic leukemia (CLL). Patients were randomly assigned (2:1 ratio) to receive IR or 6 cycles of FCR. With a median follow-up of 5.8 years, median progression-free survival (PFS) is superior for IR (hazard ratio [HR], 0.37; P < .001). IR improved PFS relative to FCR in patients with both immunoglobulin heavy chain variable region (IGHV) gene mutated CLL (HR: 0.27; P < .001) and IGHV unmutated CLL (HR: 0.27; P < .001). Among the 354 patients randomized to IR, 214 (60.5%) currently remain on ibrutinib. Among the 138 IR-treated patients who discontinued treatment, 37 (10.5% of patients who started IR) discontinued therapy due to disease progression or death, 77 (21.9% of patients who started IR) discontinued therapy for adverse events (AEs)/complications, and 24 (6.8% of patients who started IR) withdrew for other reasons. Progression was uncommon among patients able to remain on ibrutinib. The median time from ibrutinib discontinuation to disease progression or death among those who discontinued treatment for a reason other than progression was 25 months. Sustained improvement in overall survival (OS) was observed for patients in the IR arm (HR, 0.47; P = .018). In conclusion, IR therapy offers superior PFS relative to FCR in patients with IGHV mutated or unmutated CLL, as well as superior OS. Continuous ibrutinib therapy is tolerated beyond 5 years in the majority of CLL patients. This trial was registered at www.clinicaltrials.gov as #NCT02048813.

Gaps and opportunities in the treatment of relapsed-refractory multiple myeloma: Consensus recommendations of the NCI Multiple Myeloma Steering Committee

A wide variety of new therapeutic options for Multiple Myeloma (MM) have recently become available, extending progression-free and overall survival for patients in meaningful ways. However, these treatments are not curative, and patients eventually relapse, necessitating decisions on the appropriate choice of treatment(s) for the next phase of the disease. Additionally, an important subset of MM patients will prove to be refractory to the majority of the available treatments, requiring selection of effective therapies from the remaining options. Immunomodulatory agents (IMiDs), proteasome inhibitors, monoclonal antibodies, and alkylating agents are the major classes of MM therapies, with several options in each class. Patients who are refractory to one agent in a class may be responsive to a related compound or to a drug from a different class. However, rules for selection of alternative treatments in these situations are somewhat empirical and later phase clinical trials to inform those choices are ongoing. To address these issues the NCI Multiple Myeloma Steering Committee formed a relapsed/refractory working group to review optimal treatment choices, timing, and sequencing and provide recommendations. Additional issues considered include the role of salvage autologous stem cell transplantation, risk stratification, targeted approaches for genetic subsets of MM, appropriate clinical trial endpoints, and promising investigational agents. This report summarizes the deliberations of the working group and suggests potential avenues of research to improve the precision, timing, and durability of treatments for Myeloma.

Reaching beyond maximum grade: progress and future directions for modernising the assessment and reporting of adverse events in haematological malignancies

Remarkable improvements in outcomes for many haematological malignancies have been driven primarily by a proliferation of novel therapeutics over the past two decades. Targeted agents, immune and cellular therapies, and combination regimens have adverse event profiles distinct from conventional finite cytotoxic chemotherapies. In 2018, a Commission comprising patient advocates, clinicians, clinical investigators, regulators, biostatisticians, and pharmacists representing a broad range of academic and clinical cancer expertise examined issues of adverse event evaluation in the context of both newer and existing therapies for haematological cancers. The Commission proposed immediate actions and long-term solutions in the current processes in adverse event assessment, patient-reported outcomes in haematological malignancies, toxicities in cellular therapies, long-term toxicity and survivorship in haematological malignancies, issues in regulatory approval from an international perspective, and toxicity reporting in haematological malignancies and the real-world setting. In this follow-up report, the Commission describes progress that has been made in these areas since the initial report.

SWOG 1918: A phase II/III randomized study of R-miniCHOP with or without oral azacitidine (CC-486) in participants age 75 years or older with newly diagnosed aggressive non-Hodgkin lymphomas - Aiming to improve therapy, outcomes, and validate a prospective frailty tool

Diffuse large B cell lymphoma (DLBCL) is an aggressive but potentially curable malignancy; however, cure is highly dependent on the ability to deliver intensive, anthracycline-based chemoimmunotherapy. Nearly one third of cases of DLBCL occur in patients over age 75 years, and advanced age is an important adverse feature in prognostic models. Despite this incidence in older patients, there is no clear accepted standard of care due to under-representation of this group in large randomized clinical trials. Furthermore, insufficient assessments of baseline frailty and prediction of toxicity hamper clinical decision-making. Here, we present an ongoing randomized study of R-miniCHOP chemoimmunotherapy with or without oral azacitidine (CC-486, Onureg) for patients age 75 and older with newly diagnosed DLBCL and associated aggressive lymphomas. The incorporation of an oral hypomethylating agent is based on increased tumor methylation as a biologic feature of older patients with DLBCL and a desire to minimize the injection burden for this population. This is the first randomized study in this population conducted in North America by the National Clinical Trials Network (NCTN) and will enroll up to 422 patients including 40 patients in a safety run-in phase. This study incorporates an objective assessment of baseline frailty (the FIL Tool) and a serial comprehensive geriatric assessment (CGA). Key correlative tests will include circulating tumor DNA (ctDNA) assays at pre-specified timepoints to explore if ctDNA quantity and methylation patterns correlate with response. S1918 has the potential to impact future trial design and to change the standard of care for patients 75 years and older with aggressive lymphoma given its randomized design, prospective incorporation of geriatric assessments, and exploration of ctDNA correlatives. Trial registration: The trial is registered with ClinicalTrial.gov Identifier NCT04799275.

Adverse event burden in older patients with CLL receiving bendamustine plus rituximab or ibrutinib regimens: Alliance A041202

Ibrutinib has superior progression-free survival compared with bendamustine plus rituximab (BR) in older CLL patients, however, differences in treatment duration, six monthly BR cycles versus continuous ibrutinib, complicate adverse event (AE) comparisons. We introduce the AE burden score (AE_sc) to compare AEs, calculated for each patient by summing over products of reporting period length and grade for each all-cause grade 1-4 AE and dividing by the length of time over which AEs are assessed. A total of 176 patients received BR and 361 ibrutinib alone or with six cycles of rituximab. At 38 months median follow-up, 64% remained on ibrutinib. Median AE_sc was higher with BR versus ibrutinib in the first six cycles (7.2 versus 4.9, p < 0.0001). Within ibrutinib arms, median AE_sc decreased significantly to 3.7 after six cycles (p < 0.0001). 10% and 14% of BR and ibrutinib patients discontinued treatment for AEs. In ibrutinib arms, cumulative incidence of grade 3 or higher atrial fibrillation, hypertension, and infection (AEs of clinical interest) at 12 months was 4.5%, 17.5%, and 12.8%, respectively, and increased more slowly thereafter to 7.7%, 25.4%, and 20.5% at 36 months. Analytical tools including the AE_sc and cumulative incidence of AEs can help to better characterize AE burden over time. ClinicalTrials.gov identifier: NCT01886872.