US FDA's Dose Optimization Postmarketing Requirements and Commitments of Oncology Approvals and the Impact on Product Labels from 2010 to 2022: An Emerging Landscape from Traditional to Novel Therapies.

BACKGROUND: Dose optimization is a focal point of many US Food and Drug Administration (FDA) drug approvals. We sought to understand the impact of the FDA's Postmarketing Commitments/Postmarketing Requirements (PMCs/PMRs) on dose optimization and prescriber labeling for oncology drugs. METHODS: Publicly available information was aggregated for all FDA oncology drug approvals between January 1, 2010, and December 31, 2022. Study completion dates were compared to product labeling before and after PMC/PMR fulfillment dates to evaluate labeling changes associated with dose-related PMCs/PMRs. Data were analyzed individually (2010-2015 and 2016-2022) due to differences in available information. RESULTS: From 2010 to 2015, 14 of 42 (33.3%) new molecular entities (NMEs) had dose-related PMCs/PMRs, with 6 of 14 (42.9%) resulting in a relevant label change. From 2016 to 2022, of the 314 new or supplemental applications approved, 21 had dose-related PMCs/PMRs (6.7%), which trended upward over time; 71.4% of dose-related PMCs/PMRs were NMEs. Kinase inhibitors (KIs) and antibody/peptide drug conjugates (ADCs/PDCs) were the most affected drug classes. Ten of the 21 approvals with dose-related PMCs/PMRs fulfilled their dosing PMCs/PMRs, and 3 of the 10 (30%) had relevant label changes. CONCLUSION: Most dose-related PMRs/PMCs were issued for NMEs. Of these, KIs and ADCs/PDCs were highly represented, reflecting their novelty and greater uncertainty around their safety profile. PMC/PMR issuance broadly increased over time. With the implementation of the FDA's Project Optimus in 2021, it remains to be seen whether fewer dose-related PMCs/PMRs emerge in future due to enhanced dose optimization in the premarketing setting.

The Association Between Baseline Hepatic or Renal Function and Clinical Outcomes for Patients With Non-Small Cell Lung Cancer Treated With a PD-1/PD-L1 Blocking Antibody Using Real-World and Trial Data.

Clinical trials have demonstrated the benefit of PD-1/PD-L1 blocking antibodies for the treatment of patients with advanced non-small cell lung cancer (NSCLC) in defined patient populations that often exclude patients with moderate or severe hepatic or renal impairment. We assessed the association between overall survival (OS) and baseline organ function in patients with advanced NSCLC treated with PD-1/PD-L1 blocking antibodies in real-world data (RWD; patient-level data from electronic health records) and pooled clinical trial data submitted to the US Food and Drug Administration (FDA). The Kaplan-Meier estimator was used to estimate OS in different subgroups based on organ function. Unadjusted and adjusted Cox proportional hazards models were used to estimate the association between OS and organ function. In this hypothesis-generating study, baseline renal impairment did not appear to be associated with OS, while patients with baseline liver impairment had shorter OS. RWD provided information on a broader range of renal and hepatic function than was evaluated in clinical trials and hold promise to complement trial data in better understanding populations not represented in clinical trials.

Clinical Trial Diversity in Oncology: FDA Takes Action with Post-Marketing Requirements or Commitments.

In recent years, there has been a renewed focus on promoting the inclusion of patients from racial and ethnic minority groups in oncology clinical trials. FDA Oncology has long pointed to the underrepresentation of racial minorities in registration trials leading to approval. US FDA's Guidance on diversity discusses how diversity could be handled within clinical trials, giving recommendations on broadening eligibility criteria, inclusive trial practices, and alternative trial designs. While there is no specific guidance from the FDA on cancer clinical trials, the recommendation is to include a representative population applicable to the US population. With the recent renewed focus on diversity in oncology clinical trials, FDA Oncology has recently asked for the completion of a Diversity Plan during drug development and has issued post-marketing commitments and requirements at the time of approval. As FDA has started to issue post-marketing requirements or commitments regarding diversity in 2020, we sought to analyze the post-marketing studies asking for a study of racial and ethnic minorities issued by the FDA's Office of Oncologic Diseases (OOD). The analysis demonstrated the need to increase the enrollment of a diverse patient population in cancer clinical trials.

Response Rate, Event-Free Survival, and Overall Survival in Newly Diagnosed Acute Myeloid Leukemia: US Food and Drug Administration Trial-Level and Patient-Level Analyses.

PURPOSE: To explore trial-level and patient-level associations between response (complete remission [CR] and CR + CR with incomplete hematologic [CRi] or platelet [CRp] recovery), event-free survival (EFS), and overall survival (OS) in newly diagnosed acute myeloid leukemia (AML) trials of intensive chemotherapy. METHODS: We identified data from eight randomized, active-controlled trials of intensive chemotherapy submitted to the US Food and Drug Administration for treatment of newly diagnosed AML (N = 4,482). Associations between trial-level odds ratios (ORs) for CR and CR + CRi or CRp, and hazard ratios (HRs) for EFS and OS were analyzed using weighted linear regression models. We performed patient-level responder analyses to compare OS by response using pooled data from all studies. RESULTS: In trial-level analyses, association between HR for OS and OR for CR was moderate (R2 = 0.49; 95% CI, 0.05 to 0.86), as was the association with OR for CR + CRi or CRp (R2 = 0.48; 95% CI, 0.05 to 0.99). For OS versus EFS, a strong association was observed (R2 = 0.87; 95% CI, 0.47 to 0.98) when EFS definitions were harmonized across trials using raw data. In the patient-level responder analyses, patients who achieved CR had better OS compared with CRi or CRp responders (0.73; 95% CI, 0.64 to 0.84) and nonresponders (HR, 0.33; 95% CI, 0.31 to 0.37). CONCLUSION: On a trial level, there is a moderate association between OS and CR rate. A strong association between EFS and OS was observed. However, CIs were wide, and results became moderate using alternative definitions for EFS. Patient-level analyses showed CR responders have better OS compared with CRi or CRp responders and nonresponders. A therapy in newly diagnosed AML with benefit in EFS or substantial benefit in CR rate would be likely to have an OS effect.

Model Development of CDK4/6 Predicted Efficacy in Patients With Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Advanced or Metastatic Breast Cancer.

PURPOSE: Three cyclin-dependent kinase 4/6 inhibitors (CDKIs) are approved by the US Food and Drug Administration for the treatment of patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced or metastatic breast cancer in combination with hormonal therapy (HT). We hypothesized that on an individual basis, efficacy outcomes and adverse event (AE) development can be predicted using baseline patient and tumor characteristics. METHODS: Individual-level data from seven randomized controlled trials submitted to the US Food and Drug Administration for new or supplemental marketing applications of CDKIs were pooled. Progression-free survival (PFS), overall survival (OS), and AE prediction models were developed for specific treatment regimens (HT v HT plus CDKI). An individual's characteristics were used in all models simultaneously to create a group of predicted outcomes that are comparable across treatment settings. RESULTS: Accuracy of the PFS and OS prediction models for HT were 66% and 64%, respectively, with the strongest predictors being menopausal status and therapy line. The corresponding AE prediction models resulted in an average area under the curve of 0.613. Accuracy of the PFS and OS prediction models for HT plus CDKI were 62% and 63%, respectively, with the strongest predictors being histologic grade for both. The corresponding AE prediction models resulted in an average area under the curve of 0.639. CONCLUSION: This exploratory analysis demonstrated that models of efficacy outcomes and AE development can be developed using baseline patient and tumor characteristics. Comparison of paired models can inform treatment selection for individuals on the basis of the patient's personalized goals and concerns. Although use of CDKIs is standard of care in the first- or second-line setting, this model provides prognostic information that may inform individual treatment decisions.

Systematic Review of PD-1/PD-L1 Inhibitors in Oncology: From Personalized Medicine to Public Health.

BACKGROUND: To review and summarize all U.S. Food and Drug Administration (FDA) approvals of programmed death (PD)-1 and PD-ligand 1 blocking antibodies (collectively referred to as PD-[L]1 inhibitors) over a 6-year period and corresponding companion/complementary diagnostic assays. MATERIALS AND METHODS: To determine the indications and pivotal trials eligible for inclusion, approval letters and package inserts available on Drugs@FDA were evaluated for approved PD-[L]1 inhibitors to identify all new indications granted from the first approval of a PD-[L]1 inhibitor on September 4, 2014, through September 3, 2020. The corresponding FDA drug and device reviews from the marketing applications for the approved indications were identified through FDA internal records. Two reviewers independently extracted information for the endpoints, efficacy data, basis for approval, type of regulatory approval, and corresponding in vitro diagnostic device test. The results were organized by organ system and tumor type. RESULTS: Of 70 Biologic Licensing Application or supplement approvals that resulted in new indications, 32 (46%) were granted based on response rate (ORR) and durability of response, 26 (37%) on overall survival, 9 (13%) on progression-free survival, 2 (3%) on recurrence-free survival, and 1 (1%) on complete response rate. Most ORR-based approvals were granted under the accelerated approval provisions and were supported with prolonged duration of response. Overall, 21% of approvals were granted with a companion diagnostic. Efficacy results according to tumor type are discussed. CONCLUSION: PD-[L]1 inhibitors are an effective anticancer therapy in a subset of patients. This class of drugs has provided new treatment options for patients with unmet need across a wide variety of cancer types. Yet, the modest response rates in several tumor types signal a lack of understanding of the biology of these diseases. Further preclinical and clinical investigation may be required to identify a more appropriate patient population, particularly as drug development continues and additional treatment alternatives become available. IMPLICATIONS FOR PRACTICE: The number of PD-[L]1 inhibitors in drug development and the associated companion and complementary diagnostics have led to regulatory challenges and questions regarding generalizability of trial results. The interchangeability of PD-L1 immunohistochemical assays between PD-1/PD-L1 drugs is unclear. Furthermore, robust responses in some patients with low levels of PD-L1 expression have limited the use of PD-L1 as a predictive biomarker across all cancers, particularly in the setting of diseases with few alternative treatment options. This review summarizes the biomarker thresholds and assays approved as complementary and companion diagnostics and provides regulatory perspective on the role of biomarkers in oncology drug development.

Reducing Uninformative IND Safety Reports: A List of Serious Adverse Events anticipated to Occur in Patients with Lung Cancer.

Expedited reporting of unexpected serious adverse reactions that occur during clinical trials conducted under an IND is a critical component of the clinical trial process designed to protect patients by identifying potential safety issues with new agents. However, in recent years, the US FDA has presented extensive data about the problem of uninformative IND safety reporting. Despite published guidance documents aimed at clarifying requirements for submission of IND safety reports for individual events, there continues to be significant over-reporting of these events by many sponsors. This leads to excessive burden for the sponsors, the investigators who conduct clinical trials, and the FDA reviewers, who must evaluate each individual report submitted by the sponsor. This trend has the potential to endanger patients by obscuring true safety signals. To address this problem, LUNGevity Foundation empaneled a multi-sector working group of its Scientific and Clinical Research Roundtable (SCRT) charged with identifying ways to reduce unnecessary distribution of serious adverse events (SAEs) reports. This paper outlines the working group's activities, including a brief list of serious adverse events "anticipated" to occur within the lung cancer population that are either related to the underlying disease or condition being studied, concomitant or background therapy, or events associated with a demographic parameter such as age. These "anticipated" events, while required to be reported by investigators to sponsors, in general, should not then be individually reported by sponsors to FDA and to individual investigators in an IND safety report because these events require aggregate analysis across the development program to determine if they occur more frequently in treated versus untreated patients. This paper also includes discussion of how the use of background threshold values, generated from real-world data, could serve as one potential tool to guide sponsors in making causality assessments. If sponsors and other key stakeholders within the clinical research ecosystem embrace this type of approach and refrain from reporting "anticipated" events as single IND safety reports to the FDA staff and to each participating investigator, it could significantly reduce the amount of unnecessary reporting and serve as a model for other disease areas.

Evaluation of Serious Postmarket Safety Signals Within 2 Years of FDA Approval for New Cancer Drugs.

BACKGROUND: We examined how often new serious safety signals were identified by the U.S. Food and Drug Administration within the first 2 years after approval for new molecular entities (NMEs) for treatment of cancer that required specific regulatory actions described here. METHODS: We identified, for all NMEs approved for treatment of cancer or malignant hematology indications between 2010 and 2016, substantial safety-related changes within the first 2 years after approval, which included a new Boxed Warning or Warning and Precaution; requirement for (or modification of existing) Risk Evaluation and Mitigation Strategies (REMS); and withdrawal from the market because of safety concerns. RESULTS: Fifty-five NMEs were approved between 2010 and 2016: 32 (58%) under regular approval (RA) and 23 (42%) under accelerated approval (AA). Of these 55 NMEs, 9 (16%) had substantial safety-related changes after approval. Across all 55 NMEs, one was temporarily withdrawn from the market for safety reasons (1.8%); one (1.8%) required a new REMS; nine required labeling revisions-new Boxed Warnings were required for two NMEs (3.6%), and new Warnings and Precautions subsections were required for eight (14.6%). One drug (ponatinib) was responsible for several of the substantial safety-related changes (withdrawal, REMS, Boxed Warnings). One of 32 NMEs approved under RA required a new Warning and Precaution, whereas 7 of 23 NMEs approved under AA had substantial safety-related changes in the first 2 years after approval. CONCLUSION: Based on our analysis we conclude that although there was a greater incidence of substantial safety-related changes to AA drugs versus RA drugs, the majority of these were changes to the Warnings and Precautions and did not substantially alter the benefit-risk profile of the drug. IMPLICATIONS FOR PRACTICE: The majority of new cancer drugs (84%) approved in the U.S. do not have new substantial safety information being added to the label within the first 2 years of approval. Unprecedented efficacy seen in contemporary cancer drug development has led to early availability of effective cancer therapies based on large effects in smaller populations. More limited premarket safety data require diligent postmarketing safety surveillance as we continue to learn and update drug labeling throughout the product lifecycle.

Older adults in hematologic malignancy trials: Representation, barriers to participation and strategies for addressing underrepresentation.

Despite a high incidence of hematologic malignancies in older adults, available data indicate that there is disproportionately low representation of adults ≥65 years with hematologic malignancies (greater in patients ≥75 years) in clinical trials. Biological and clinical differences between older and younger adults and diversity within older patients necessitate adequate representation of the older subpopulation in hematologic malignancy trials. This would allow trial results to be generalizable and inform treatment decisions in the older patient population. Restrictive eligibility criteria may be barriers to adequate representation, as older adults do not typically meet these criteria. Efforts to broaden eligibility criteria in clinical trials have been proposed and may promote enrollment of a representative older population with hematologic malignancies. Collaboration among a diverse group of stakeholders will be needed to implement current proposals and evaluate their impact on increasing representation of older adults in trials evaluating therapies for hematologic malignancies.

Expanding Access to Lung Cancer Clinical Trials by Reducing the Use of Restrictive Exclusion Criteria: Perspectives of a Multistakeholder Working Group.

Low rates of adult patient participation have been a persistent problem in cancer clinical trials and have continued to be a barrier to efficient drug development. The routine use of significant exclusion criteria has contributed to this problem by limiting participation in studies and creating significant clinical differences between the study cohorts and the real-world cancer patient populations. These routine exclusions also unnecessarily restrict opportunities for many patients to access potentially promising new therapies during clinical development. Multiple efforts are underway to broaden eligibility criteria, allowing more patients to enroll in studies and generating more robust data regarding the effect of novel therapies in the population at large. Focusing specifically on lung cancer as an example, a multistakeholder working group empaneled by the LUNGevity Foundation identified 14 restrictive and potentially outdated exclusion criteria that appear frequently in lung cancer clinical trials. As a part of the project, the group evaluated data from multiple recent lung cancer studies to ascertain the extent to which these 14 criteria appeared in study protocols and played a role in excluding patients (screen failures). The present report describes the working group's efforts to limit the use of these routine exclusions and presents clinical justifications for reducing the use of 14 criteria as routine exclusions in lung cancer studies, potentially expanding trial eligibility and improving the generalizability of the results from lung cancer trials.

An Analysis of Recent FDA Oncology Scientific Publications.

In addition to its primary regulatory role, the Office of Hematology and Oncology Products at the U.S. Food and Drug Administration (FDA) is engaged in many forms of scientific authorship. During the period of 2010 to 2018, FDA oncology staff contributed to 356 publications in the scientific literature. Here, we collaborated with analysts in the Office of Program Planning, Analysis, and Evaluation at the National Institute of General Medical Sciences, National Institutes of Health (NIH), to present a series of analyses aimed at quantifying the characteristics and potential impact of these contributions, as well as characterizing the areas of work addressed. We found that FDA oncology papers are enriched for high-impact publications and have about two times the number of citations as an average NIH-funded paper. Further impact of the publications was measured based on the presence of 65 publications that were cited by guidelines and 12 publications cited by publicly listed clinical trials. The results seen here are promising in determining the impact of FDA oncology publication work but prompt further investigation into longer-term impacts, such as the influence of this work on other regulatory activities at FDA. IMPLICATIONS FOR PRACTICE: This article describes the first comprehensive study of scientific publications produced by U.S. Food and Drug Administration (FDA) oncology staff. The analysis illustrates that staff are highly engaged in publishing in the scientific literature in addition to completing regulatory review work. Publications are generally in clinical medicine, consistent with the large number of medical oncologists working at the Office of Hematology and Oncology Products (OHOP). OHOP publications generally focus either on communicating important regulatory work (approval summaries) or highlighting regulatory science issues to encourage dialogue with the scientific community (commentaries, reviews, and expert working papers). The analysis also suggests that several FDA oncology publications may influence clinical guidelines, but further work is needed to evaluate impact.

FDA Approval Summary: Ruxolitinib for Treatment of Steroid-Refractory Acute Graft-Versus-Host Disease.

On May 24, 2019, the Food and Drug Administration approved ruxolitinib for steroid-refractory acute graft-versus-host disease (SR-aGVHD) in adult and pediatric patients 12 years and older. Approval was based on Study INCB 18424-271 (REACH-1; NCT02953678), an open-label, single-arm, multicenter trial that included 49 patients with grades 2-4 SR-aGVHD occurring after allogeneic hematopoietic stem cell transplantation. Ruxolitinib was administered at 5 mg twice daily, with dose increases to 10 mg twice daily permitted after 3 days in the absence of toxicity. The Day-28 overall response rate was 57.1% (95% confidence interval [CI]: 42.2-71.2). The median duration of response was 0.5 months (95% CI: 0.3-2.7), and the median time from Day-28 response to either death or need for new therapy for acute GVHD was 5.7 months (95% CI: 2.2 to not estimable). Common adverse reactions included anemia, thrombocytopenia, neutropenia, infections, edema, bleeding, and elevated transaminases. Ruxolitinib is the first drug approved for treatment of SR-aGVHD. IMPLICATIONS FOR PRACTICE: Ruxolitinib is the first Food and Drug Administration-approved treatment for steroid-refractory acute graft-versus-host disease in adult and pediatric patients 12 years and older. Its approval provides a treatment option for the 60% of those patients who do not respond to steroid therapy.

FDA Approval Summary: Atezolizumab Plus Paclitaxel Protein-bound for the Treatment of Patients with Advanced or Metastatic TNBC Whose Tumors Express PD-L1.

On March 8, 2019, the FDA granted accelerated approval to atezolizumab in combination with paclitaxel protein-bound for the treatment of adult patients with unresectable locally advanced or metastatic triple-negative breast cancer (TNBC) whose tumors express PD-L1 [PD-L1 stained tumor-infiltrating immune cells (IC) of any intensity covering ≥1% of the tumor area], as determined by an FDA-approved test. Approval was based on data from IMpassion130, which randomized patients to receive atezolizumab or placebo in combination with paclitaxel protein-bound. Investigator-assessed progression-free survival (PFS) in the intent-to-treat (ITT) and PD-L1-positive populations were coprimary endpoints. After 13-month median follow-up, the estimated median PFS in the PD-L1-positive population was 7.4 months in the atezolizumab arm and 4.8 months in the placebo arm [HR = 0.60; 95% confidence interval (CI), 0.48-0.77]. Overall survival (OS) results were immature with 43% deaths in the ITT population, representing 59% of the OS events required to perform the final OS analysis. Adverse reactions occurring in ≥20% of patients receiving atezolizumab with paclitaxel protein-bound were alopecia, peripheral neuropathies, fatigue, nausea, diarrhea, anemia, constipation, cough, headache, neutropenia, vomiting, and decreased appetite. Accelerated approval was appropriate taking into account the unmet medical need along with the immaturity of the OS results and potential for PFS in the PD-L1-expressing population to predict clinical benefit.

FDA Approval Summary: Tagraxofusp-erzs For Treatment of Blastic Plasmacytoid Dendritic Cell Neoplasm.

Tagraxofusp-erzs (Elzonris, Stemline) is a cytotoxin that targets CD123-expressing cells. On December 21, 2018, FDA approved tagraxofusp-erzs for the treatment of blastic plasmacytoid dendritic cell neoplasms (BPDCN) in adult and pediatric patients 2 years and older. Approval was based on the response rate in a single-arm trial, Study STML-401-0114; the pivotal cohort included 13 patients with treatment-naïve BPDCN who received tagraxofusp-erzs monotherapy. The complete response or clinical complete response (CR/CRc) rate in the pivotal cohort was 54% (95% CI: 25%-81%), and the median duration of CR/CRc was not reached with a median follow-up of 11.5 months (range: 0.2-12.7). In a separate exploratory cohort, a CR/CRc was achieved by 2 (13%) patients with R/R BPDCN. Safety was assessed in 94 patients with myeloid neoplasms treated with tagraxofusp-erzs at the approved dose and schedule. The major toxicity was capillary leak syndrome (CLS), which occurred in 55% of patients and was fatal in 2%. Hepatotoxicity and hypersensitivity reactions were reported in 88% and 46% of patients, respectively. Other common (≥30%) adverse reactions were nausea, fatigue, peripheral edema, pyrexia, and weight increase. A high proportion of patients (85%) developed neutralizing antidrug antibodies. Tagraxofusp-erzs is the first FDA-approved treatment for BPDCN.

FDA Approval Summary: Calaspargase Pegol-mknl For Treatment of Acute Lymphoblastic Leukemia in Children and Young Adults.

On December 20, 2018, the Food and Drug Administration approved calaspargase pegol-mknl (CALASP), an asparagine-specific enzyme, as a component of a multi-agent chemotherapeutic regimen for acute lymphoblastic leukemia (ALL) in pediatric and young adult patients age 1 month to 21 years. Efficacy was determined on the basis of achievement and maintenance of steady-state nadir serum asparaginase activity (NSAA) above 0.1 U/mL when using CALASP, 2,500 U/m2 intravenously, every 3 weeks. In a randomized comparison to pegaspargase (PEGASP) every 2 weeks, treatment with CALASP every 3 weeks had a similar safety profile and no substantial impairment in event-free survival. The pharmacokinetics of CALASP were studied when administered in combination with multiagent chemotherapy in 124 patients with B-cell ALL in Study AALL07P4 and Study DFCI 11-001. The results showed that 123 [99%, 95% confidence interval (CI), 96%-100%] of the 124 patients maintained NSAA >0.1 U/mL at weeks 6, 12, 18, 24, and 30 of post-induction phase. Maintaining adequate NSAA levels is critical to successful treatment of ALL. Herein, we describe the FDA review and approval of CALASP.See related commentary by Lew, p. 325.