Impact of Increasing PD-L1 Levels on Outcomes to PD-1/PD-L1 Inhibition in Patients With NSCLC: A Pooled Analysis of 11 Prospective Clinical Trials

BACKGROUND

Programmed death ligand 1 (PD-L1) expression is recognized as a key biomarker in the treatment of non-small cell lung cancer (NSCLC) with anti-PD(L)1 inhibitors. Previous work has highlighted that outcomes in patients with NSCLC treated with anti-PD(L)1 inhibitors generally improve with increasing PD-L1 expression. The objectives of these analyses are to quantitate the effect of PD-L1 expression on outcomes, to characterize the potentially nonlinear relationship between PD-L1 expression and outcomes, and to assess potential differences in these relationships across subgroups.

PATIENTS AND METHODS

We performed a retrospective, pooled analysis of 11 clinical trials submitted to the US FDA between 2015 and 2022 that included patients with advanced NSCLC treated with anti-programmed death 1 or anti-PD-L1 immune checkpoint inhibitor (ICI) monotherapy in the first-line (1L) or second-line (2L) treatment setting. The clinical outcomes explored were overall survival (OS), progression-free survival (PFS), and objective response rate (ORR).

RESULTS

The primary analysis population included 3806 patients with advanced NSCLC, of which 2040 were treated in 1L and 1766 in 2L. For patients with a PD-L1 score of 100% in the 1L setting, the hazard ratio versus a patient with 1% PD-L1 was 0.55 (95% CI, 0.43 to 0.70) for OS and 0.50 (95% CI, 0.41 to 0.61) for PFS. For patients with a PD-L1 score of 100% in the 2L setting, the hazard ratio versus a patient with 0% PD-L1 was 0.55 (95% CI, 0.43 to 0.71) for OS and 0.51 (95% CI, 0.41 to 0.63) for PFS. Subgroup analyses suggested that this relationship may vary by subgroup, particularly by region.

CONCLUSIONS

These analyses suggest PD-L1 expression has an appreciable impact on clinical outcomes for patients with NSCLC treated with ICI. As the impact of PD-L1 expression on outcomes may vary across regions, it is critical that future trials are multiregional and enroll a diverse patient population.

FDA Approval Summary: Alpelisib for PIK3CA-Related Overgrowth Spectrum

On April 5, 2022, FDA granted accelerated approval to alpelisib for the treatment of adult and pediatric patients 2 years of age and older with severe manifestations of PIK3CA-related overgrowth spectrum (PROS) who require systemic therapy. Efficacy was evaluated using real-world data (RWD) from EPIK-P1 (NCT04285723), a single-arm clinical study in patients 2 years of age and older with severe or life-threatening PROS who received alpelisib as part of an expanded access program (EAP) for compassionate use. The primary endpoint was confirmed radiologic response rate at week 24 as determined by blinded independent central review (BICR), using volumetric-based criteria given the atypical growth pattern and irregular shape of PROS lesions. Radiologic response was defined as a ≥20% reduction from baseline in the sum of measurable target lesion volume in up to three lesions. Of the 37 patients in the efficacy population, 27% [95% confidence interval (CI), 14-44] had a radiologic response at week 24. Duration of response (DOR) was an additional efficacy outcome measure, and among responders, 60% had a response lasting ≥12 months. Furthermore, supportive clinical documentation suggested early signals of clinical benefit (i.e., improvement in PROS-related signs and symptoms). The most common (≥10%) adverse reactions were diarrhea, stomatitis, and hyperglycemia.

A U.S. Food and Drug Administration-pooled Analysis of Frontline Combination Treatment Survival Benefits by Risk Groups in Metastatic Renal Cell Carcinoma

BACKGROUND

While frontline immuno-oncology/tyrosine kinase inhibitor (IO/TKI) combination therapy has established a benefit in metastatic renal cell carcinoma (mRCC), this may differ by International Metastatic RCC Database Consortium (IMDC) risk grouping. Looking at individual trials, we noted an apparently smaller magnitude of benefit for favorable-risk disease.

OBJECTIVE

We aimed to assess treatment benefit by risk groupings, especially in favorable-risk, augmenting patient numbers via a pooled analysis.

DESIGN, SETTING, AND PARTICIPANTS

We pooled four frontline mRCC trials of IO/TKI combinations including 3,098 patients (839 favorable-risk) with approvals from 2019 to 2021.

INTERVENTION

All trials used IO/TKI combinations as the treatment option and sunitinib as the control.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We analyzed progression-free survival (PFS) and overall survival (OS) by IMDC groupings. To specifically address the favorable-risk group, we combined all others into an intermediate/poor-risk group.

RESULTS AND LIMITATIONS

In this exploratory analysis adjusted for baseline covariates, IO/TKI combinations have yet to demonstrate an OS benefit in favorable-risk (hazard ratio [HR] 1.24; 95% confidence interval [CI]: 0.86, 1.78) despite demonstrating an OS benefit in the intermediate/poor-risk group (HR 0.64; 95% CI: 0.55, 0.75). In contrast, IO/TKI demonstrated a PFS benefit for both the favorable-risk (HR 0.63; 95% CI: 0.50, 0.79) and the intermediate/poor-risk (HR 0.52; 95% CI: 0.45, 0.60) group. For objective response rate, a smaller difference was observed between the combination and sunitinib arms in favorable-risk (68.2% vs 49.9%) versus intermediate/poor-risk (59.9% vs 36.5%) groups, while the difference in complete response rate was larger for favorable-risk (15.3% vs 6.0%) versus intermediate/poor-risk (9.1% vs 3.4%) groups.

CONCLUSIONS

The frontline IO/TKI combination therapy benefit was shown to be greater in the intermediate/poor-risk group than in the favorable-risk group. The OS benefit observed with IO/TKI for mRCC has yet to be demonstrated for favorable-risk patients; longer follow-up is needed.

PATIENT SUMMARY

Patients with intermediate/poor-risk metastatic renal cell carcinoma derive an overall survival benefit from immuno-oncology/tyrosine kinase inhibitor combinations, while data for favorable-risk remain immature.

FDA Approval Summary: Amivantamab for the Treatment of Patients with Non-Small Cell Lung Cancer with EGFR Exon 20 Insertion Mutations

The FDA granted accelerated approval for amivantamab-vmjw (hereafter referred to as amivantamab), a bispecific antibody directed against EGFR and mesenchymal-epithelial transition receptor, on May 21, 2021, for the treatment of adult patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) with EGFR exon 20 insertion mutations whose disease has progressed on or after platinum-based chemotherapy. Approval was based on results of an ongoing, multicenter, nonrandomized, open-label, multicohort clinical trial (CHRYSALIS, NCT02609776), demonstrating a substantial overall response rate (ORR) and durable responses, with an ORR of 40% [95% confidence interval (CI): 29-51] and a median response duration of 11.1 months (95% CI: 6.9-not evaluable). Guardant360 CDx was contemporaneously approved as a companion diagnostic for this indication to identify EGFR exon 20 insertion mutations in plasma specimens. The most notable safety finding was the high incidence (66%) of infusion-related reactions, which is addressed in both the Dosage and Administration and Warnings and Precautions sections of the product label. Other common adverse reactions (occurring in ≥20% of patients) were rash, paronychia, musculoskeletal pain, dyspnea, nausea and vomiting, fatigue, edema, stomatitis, cough, and constipation. The approval of amivantamab was the first approval of a targeted therapy for patients with advanced NSCLC harboring EGFR exon 20 insertion mutations.

FDA Approval Summary: Atezolizumab as Adjuvant Treatment following Surgical Resection and Platinum-Based Chemotherapy for Stage II to IIIA NSCLC

On October 15, 2021, the FDA approved atezolizumab as adjuvant therapy in patients with stage II to IIIA non-small cell lung cancer (NSCLC) whose tumors have programmed cell death ligand 1 (PD-L1) expression on ≥1% of tumor cells (TC), as detected by an FDA-approved test. The approval was based on results from the IMpower010 trial, in which 1,005 patients with NSCLC who had completed tumor resection and cisplatin-based adjuvant chemotherapy were randomly assigned 1:1 to receive atezolizumab for 16 cycles or best supportive care. The primary endpoint of disease-free survival (DFS) as assessed by investigator was tested hierarchically in the following analysis populations: stage II-IIIA NSCLC with PD-L1 expression on ≥1% of TCs (PD-L1 ≥ 1% TC); all randomly assigned patients with stage II-IIIA NSCLC; and the intent-to-treat population comprising all randomly assigned patients. At the prespecified interim DFS analysis, IMpower010 demonstrated a statistically significant and clinically meaningful improvement in DFS in the stage II-IIIA PD-L1 ≥ 1% TC analysis population, with an HR of 0.66 (95% confidence interval, 0.50-0.88; P = 0.004) favoring the atezolizumab arm. The safety profile of atezolizumab was generally consistent with known toxicities of anti-PD-(L) antibodies. The VENTANA PD-L1 (SP263) Assay (Ventana Medical Systems, Inc.) was contemporaneously approved as a companion diagnostic device to select patients with NSCLC who are PD-L1 ≥ 1% TC for adjuvant treatment with atezolizumab. Atezolizumab is the first immune checkpoint inhibitor approved by FDA for the adjuvant treatment of NSCLC.

Trends in the approval of cancer therapies by the FDA in the twenty-first century

The cancer treatment landscape has changed dramatically since the turn of the century, resulting in substantial improvements in outcomes for patients. This Review summarizes trends in the approval of oncology therapeutic products by the United States Food and Drug Administration (FDA) from January 2000 to October 2022, based on a categorization of these products by their mechanism of action and primary target. Notably, the rate of oncology indication approvals has increased in this time, driven by approvals for targeted therapies, as has the rate of introduction of new therapeutic approaches. Kinase inhibitors are the dominant product class by number of approved products and indications, yet immune checkpoint inhibitors have the second most approvals despite not entering the market until 2011. Other trends include a slight increase in the share of approvals for biomarker-defined populations and the emergence of tumour-site-agnostic approvals. Finally, we consider the implications of the trends for the future of oncology therapeutic product development, including the impact of novel therapeutic approaches and technologies.

US Food and Drug Administration Approval Summary: Nivolumab Plus Platinum-Doublet Chemotherapy for the Neoadjuvant Treatment of Patients With Resectable Non-Small-Cell Lung Cancer

PURPOSE

On March 4, 2022, the US Food and Drug Administration (FDA) approved nivolumab plus platinum-doublet chemotherapy for the neoadjuvant treatment of patients with resectable non-small-cell lung cancer (NSCLC). We discuss the FDA's review of the key data and regulatory considerations supporting this approval.

PATIENTS AND METHODS

The approval was based on the results of CheckMate 816, an international, multiregional, active-controlled trial that randomly assigned 358 patients with resectable NSCLC, stage IB (≥4 cm) to IIIA (N2) per the American Joint Committee on Cancer seventh staging edition to receive either nivolumab plus platinum-doublet or platinum-doublet chemotherapy alone for three cycles before planned surgical resection. The major efficacy end point that supported this approval was event-free survival (EFS).

RESULTS

At the first planned interim analysis (IA), the hazard ratio (HR) for EFS was 0.63 (95% CI, 0.45 to 0.87; P = .0052; statistical significance boundary = .0262) favoring the nivolumab plus chemotherapy arm; the median EFS was 31.6 months (95% CI, 30.2 to not reached) in the nivolumab plus chemotherapy arm versus 20.8 months (95% CI, 14.0 to 26.7) in the chemotherapy-only arm. At the time of a prespecified IA for overall survival (OS), 26% of patients had died, and the HR for OS was 0.57 (95% CI, 0.38 to 0.87; P = .0079; statistical significance boundary = .0033). Eighty-three percent of patients in the nivolumab-containing arm versus 75% in the chemotherapy-only arm received definitive surgery.

CONCLUSION

This approval, the first for any regimen for the neoadjuvant treatment of NSCLC in the United States, was supported by a statistically significant and clinically meaningful improvement in EFS with no evidence of detriment in OS or negative impact on patients' receipt and timing of surgery or surgical outcomes.

The Development of the Oncology Center of Excellence Patient-Friendly Language Glossary of Oncology Clinical Trial Terms

Oncology clinical trials terms and definitions have become increasingly complex, which has led to shortcomings among research staff and healthcare providers in informing clinical trial participants with the study results and consenting procedures in simple language. Understanding oncology clinical trial terms is of critical importance to assist patients and caregivers in making cancer treatment decisions, including enrollment into clinical trials. The U.S. Food and Drug Administration's (FDA) Oncology Center of Excellence (OCE) organized a physician and patient advocate-led focus group, with the primary goal of publishing a patient-centric public glossary of select cancer clinical trial terms for healthcare providers, patients, and caregivers. This commentary reports the results of the focus group sessions that gave FDA OCE valuable insights into how patients perceive clinical trial terms and how oncology clinical trial definitions can be improved to effectively communicate information to the patients to make better informed decisions about their treatment options.

US Food and Drug Administration Approval Summary: Fam-Trastuzumab Deruxtecan-nxki for Human Epidermal Growth Factor Receptor 2-Low Unresectable or Metastatic Breast Cancer

PURPOSE

The US Food and Drug Administration approved fam-trastuzumab deruxtecan-nxki (DS-8201a, T-DXd) for the treatment of adult patients with unresectable or metastatic human epidermal growth factor receptor 2 (HER2)-low (immunohistochemistry 1 + or immunohistochemistry 2+/in situ hybridization-) breast cancer who have received a prior chemotherapy in the metastatic setting or developed disease recurrence during or within 6 months of completing adjuvant chemotherapy.

PATIENTS AND METHODS

Approval was based on DESTINY-Breast04, a phase III, randomized, open-label, multicenter trial in patients with unresectable or metastatic HER2-low breast cancer, determined at a central laboratory. A total of 557 patients were randomly assigned (2:1) to receive either T-DXd 5.4 mg/kg intravenously once every 3 weeks (n = 373) or physicians' choice of chemotherapy (n = 184).

RESULTS

The study met its primary efficacy end point of progression-free survival (PFS) by blinded independent central review assessment in the hormone receptor-positive (HR+) cohort (N = 494) with an estimated hazard ratio (HR) of 0.51(95% CI, 0.40 to 0.64; P < .0001). Key secondary end points were also met, including PFS in the intent-to-treat population with an HR of 0.50 (95% CI, 0.40 to 0.63; P < .0001), overall survival (OS) in the HR+ cohort with an HR of 0.64 (95% CI, 0.48 to 0.86; P = .0028) and OS in the intent-to-treat with an HR of 0.64 (95% CI, 0.49 to 0.84; P = .0010). The safety profile of T-DXd was consistent with previously approved indications, and no new safety signals were observed in this study population.

CONCLUSION

The approval of T-DXd in HER2-low metastatic breast cancer was based on statistically significant and clinically meaningful PFS and OS improvements observed in the DESTINY-Breast04 trial and represents the first approved therapy specifically for the treatment of HER2-low metastatic breast cancer.

Differential Protein Citrullination in Human ER- and ER+ Tumor and Adjacent Healthy Breast Tissue

Post-translational modification of arginine to citrulline is catalyzed by members of the peptidylarginine deiminase (PAD) family. Dysregulation of this catalysis is a significant driver of the pathogenesis of numerous inflammatory diseases, including cancer. However, dysregulation of PAD activity has not been examined in breast cancer with respect to hormone receptor status. In this study, we measured PAD enzyme levels using Western blotting and investigated protein citrullination using a mass spectrometry-based proteomics approach in primary estrogen receptor negative (ER-) or positive (ER+) breast tumor and matched adjacent normal tissue. Our findings reveal 72 and 41 citrullinated proteins in ER- tumor and adjacent healthy tissue, respectively, where 20 of these proteins are common between the two groups. We detected 64 and 49 citrullinated proteins in ER+ tumor and adjacent healthy tissue, respectively, where 32 proteins are common. Interestingly, upon comparison of ER- and ER+ tumor tissue, only 32 citrullinated proteins are shared between the two and the rest are unique to the tumor's receptor status. Using the STRING database for protein-protein interaction network analysis, these proteins are involved in protein-folding events (i.e., heat shock proteins) in ER- samples and blood-clotting events (i.e., fibulin) in ER+ samples. Constituents of the extracellular matrix structure (i.e., collagen and fibrinogen) were found in both. Herein, we establish evidence that supports the role of this unique post-translational modification in breast cancer biology. Finally, to aid drug discovery against citrullination, we developed a liquid chromatography-ultraviolet method to measure PAD enzymatic activity and optimized glucagon-like peptide II to quantitatively measure the ability of PADs to citrullinate its substrate.

FDA Approval Summary: Mobocertinib for Metastatic Non-Small Cell Lung Cancer with EGFR Exon 20 Insertion Mutations

On September 15, 2021, the FDA granted accelerated approval to mobocertinib (Exkivity, Takeda Pharmaceuticals USA, Inc.) for the treatment of adult patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) with EGFR exon 20 insertion mutations, as detected by an FDA-approved test, whose disease has progressed on or after platinum-based chemotherapy. The approval was based on data from Study AP32788-15-101 (NCT02716116), an international, non-randomized, multi-cohort clinical trial that included patients with locally advanced or metastatic NSCLC with EGFR exon 20 insertion mutations. The overall response rate in 114 patients whose disease had progressed on or after platinum-based chemotherapy was 28% [95% confidence interval (CI), 20%-37%] with a median duration of response of 17.5 months (95% CI, 7.4-20.3). The most common adverse reactions (>20%) were diarrhea, rash, nausea, stomatitis, vomiting, decreased appetite, paronychia, fatigue, dry skin, and musculoskeletal pain. Product labeling includes a Boxed Warning for QTc prolongation and torsades de pointes. This is the first approval of an oral targeted therapy for patients with advanced EGFR exon 20 insertion mutation-positive NSCLC.

Use of Single-Arm Trials for US Food and Drug Administration Drug Approval in Oncology, 2002-2021

Importance

Single-arm trials have allowed for transformative therapies to be made available to patients expeditiously. However, using single-arm trials to support drug approval presents several challenges that must be carefully considered.

Observations

Between January 1, 2002, and December 31, 2021, the US Food and Drug Administration granted 176 new malignant hematology and oncology indications based on single-arm trials, including 116 accelerated approvals (AAs) and 60 traditional approvals. Overall, 87 approvals (49%) were for new molecular entities or original biologics and 89 (51%) were supplemental indications. Response rate (RR) was the most common end point used to support approval in these single-arm trials (173 of 176 [98%]). Of the 116 AAs based on single-arm trials, 45 (38%) fulfilled their postmarketing requirement to verify clinical benefit, 61 (52%) are pending verification of benefit, and 10 (9%) were withdrawn from the market as of December 31, 2021. Most (56 of 61 [92%]) AAs based on single-arm trials pending verification of benefit occurred during the previous 5 years and have ongoing confirmatory trials as of December 2021.

Conclusions and Relevance

Single-arm trials have been a common development strategy to support regulatory approval as early-stage expansion cohorts with promising durable RRs have become more prevalent. In the appropriate context, single-arm trials using durable RRs can allow patients expedited access to novel therapies and will continue to serve a role in advancing drug development in oncology. However, single-arm trials have a smaller noncomparative safety data set, inability to use time-to-event end points, and other limitations that require careful consideration within the context of the disease and available therapies. The randomized clinical trial remains the preferred approach in clinical investigation.

Regulatory implications of ctDNA in immuno-oncology for solid tumors

In the era of precision oncology, use of circulating tumor DNA (ctDNA) is emerging as a minimally invasive approach for the diagnosis and management of patients with cancer and as an enrichment tool in clinical trials. In recent years, the US Food and Drug Administration has approved multiple ctDNA-based companion diagnostic assays for the safe and effective use of targeted therapies and ctDNA-based assays are also being developed for use with immuno-oncology-based therapies. For early-stage solid tumor cancers, ctDNA may be particularly important to detect molecular residual disease (MRD) to support early implementation of adjuvant or escalated therapy to prevent development of metastatic disease. Clinical trials are also increasingly using ctDNA MRD for patient selection and stratification, with an ultimate goal of improving trial efficiency through use of an enriched patient population. Standardization and harmonization of ctDNA assays and methodologies, along with further clinical validation of ctDNA as a prognostic and predictive biomarker, are necessary before ctDNA may be considered as an efficacy-response biomarker to support regulatory decision making.

FDA Approval Summary: Nivolumab for the Adjuvant Treatment of Adults with Completely Resected Esophageal/Gastroesophageal Junction Cancer and Residual Pathologic Disease

The FDA approved nivolumab on May 20, 2021, for the adjuvant treatment of completely resected (negative margins) esophageal or gastroesophageal junction cancer (EC/GEJC) in patients who had residual pathologic disease following chemoradiotherapy. The approval was based on data from the double-blind CheckMate 577 trial, which randomly allocated patients to receive nivolumab or placebo. Disease-free survival (DFS) was the primary endpoint. At the time of the final DFS analysis and the prespecified interim overall survival (OS) analysis, the estimated median DFS was 22.4 months [95% confidence interval (CI), 16.6-34.0] in the nivolumab arm versus 11.0 months (95% CI, 8.3-14.3) in the placebo arm, with an HR of 0.69 (95% CI, 0.56-0.85; two-sided P value = 0.0003). An unblinded review of OS did not indicate a detrimental effect on survival. Adverse reactions occurring in ≥20% of patients receiving nivolumab were fatigue/asthenia, diarrhea, nausea, rash, musculoskeletal pain, and cough. Approval of nivolumab is likely to change the treatment paradigm for the adjuvant treatment of patients with completely resected (negative margins) EC/GEJC who have residual pathologic disease following chemoradiotherapy based on the study results and favorable risk:benefit of nivolumab administration.

FDA Approval Summary: Pembrolizumab for Neoadjuvant and Adjuvant Treatment of Patients with High-Risk Early-Stage Triple-Negative Breast Cancer

On July 26, 2021, the FDA granted approval to pembrolizumab in combination with chemotherapy for neoadjuvant treatment and then continued as a single agent for adjuvant treatment following surgery for patients with high-risk, early-stage triple-negative breast cancer. Approval was based on results from KEYNOTE-522, an ongoing randomized (2:1) trial evaluating pembrolizumab or placebo in combination with chemotherapy for neoadjuvant treatment and then as a single agent for adjuvant treatment. The co-primary endpoints were pathological complete response (pCR) rate and event-free survival (EFS). The trial demonstrated an improvement in pCR and EFS in the pembrolizumab arm compared with the control arm. The number of patients who experienced an EFS event was 123 (16%) and 93 (24%), respectively [HR: 0.63, 95% confidence interval (CI), 0.48-0.82, P = 0.00031]. Patients on the pembrolizumab arm experienced EFS benefit regardless of tumor PD-L1 status. The absolute pCR rate improvement with the addition of pembrolizumab was 7.5% (95% CI, 1.6-13.4). Among patients receiving pembrolizumab, 44% experienced an immune-related adverse reaction. This article summarizes FDA's review of pembrolizumab and the data supporting the favorable benefit-risk assessment.

FDA Approval Summary: Belzutifan for von Hippel-Lindau Disease-Associated Tumors

On August 13, 2021, the FDA approved belzutifan (WELIREG, Merck), a first-in-class hypoxia-inducible factor (HIF) inhibitor for adult patients with von Hippel-Lindau (VHL) disease who require therapy for associated renal cell carcinoma (RCC), central nervous system (CNS) hemangioblastomas, or pancreatic neuroendocrine tumors (pNET), not requiring immediate surgery. The FDA granted approval based on the clinically meaningful effects on overall response rate (ORR) observed in patients enrolled in Study MK-6482-004. All 61 patients had VHL-associated RCC; some also had CNS hemangioblastomas and/or pNET. For VHL disease-associated RCC, ORR was 49% [95% confidence interval (CI), 36-62], median duration of response (DoR) was not reached, 56% of responders had DoR ≥12 months, and median time to response was 8 months. Twenty-four patients had measurable CNS hemangioblastomas with an ORR of 63% (95% CI, 41-81), and 12 patients had measurable pNET with an ORR of 83% (95% CI, 52-98). For these tumors, median DoR was not reached, with 73% and 50% of patients having response durations ≥12 months for CNS hemangioblastomas and pNET, respectively. The most common adverse reactions, including laboratory abnormalities, reported in ≥20% were anemia, fatigue, increased creatinine, headache, dizziness, increased glucose, and nausea. Belzutifan can render some hormonal contraceptives ineffective and can cause embryo-fetal harm during pregnancy. This article summarizes the data and the FDA thought process supporting traditional approval of belzutifan for this indication.

FDA Approval Summary: Cabozantinib for Differentiated Thyroid Cancer

On September 17, 2021, the FDA approved cabozantinib (Cabometyx; Exelixis, Inc.) for the treatment of adult and pediatric patients 12 years of age and older with locally advanced or metastatic differentiated thyroid cancer (DTC) that has progressed following prior VEGFR-targeted therapy and who are radioactive iodine (RAI)-refractory or ineligible. This is the first approval for patients with RAI-refractory locally advanced or metastatic DTC who have progressed following prior therapy and the first approval in pediatric patients with DTC. The approval was based on data from COSMIC-311 (Study XL184-311, NCT03690388), an international, randomized, double-blind trial in which patients with locally advanced or metastatic RAI-refractory DTC that progressed during or following treatment with at least one VEGFR-targeting tyrosine kinase inhibitor were treated with either cabozantinib 60 mg orally once daily (N = 170) or placebo with best supportive care (N = 88). The primary efficacy outcome measures were progression-free survival (PFS) and overall response rate (ORR) by blinded independent central review per RECIST 1.1. The median PFS was 11.0 months [95% confidence interval (CI), 7.4-13.8] in the cabozantinib arm compared with 1.9 months (95% CI, 1.9-3.7) in the control arm, with an HR of 0.22 (95% CI, 0.15-0.31). The endpoint of ORR was not met. No new safety signals were identified with the exception of hypocalcemia, which was added as a warning in the product labeling.

Changes in Circulating Tumor DNA Reflect Clinical Benefit Across Multiple Studies of Patients With Non-Small-Cell Lung Cancer Treated With Immune Checkpoint Inhibitors

PURPOSE

As immune checkpoint inhibitors (ICI) become increasingly used in frontline settings, identifying early indicators of response is needed. Recent studies suggest a role for circulating tumor DNA (ctDNA) in monitoring response to ICI, but uncertainty exists in the generalizability of these studies. Here, the role of ctDNA for monitoring response to ICI is assessed through a standardized approach by assessing clinical trial data from five independent studies.

PATIENTS AND METHODS

Patient-level clinical and ctDNA data were pooled and harmonized from 200 patients across five independent clinical trials investigating the treatment of patients with non-small-cell lung cancer with programmed cell death-1 (PD-1)/programmed death ligand-1 (PD-L1)-directed monotherapy or in combination with chemotherapy. CtDNA levels were measured using different ctDNA assays across the studies. Maximum variant allele frequencies were calculated using all somatic tumor-derived variants in each unique patient sample to correlate ctDNA changes with overall survival (OS) and progression-free survival (PFS).

RESULTS

We observed strong associations between reductions in ctDNA levels from on-treatment liquid biopsies with improved OS (OS; hazard ratio, 2.28; 95% CI, 1.62 to 3.20; P < .001) and PFS (PFS; hazard ratio 1.76; 95% CI, 1.31 to 2.36; P < .001). Changes in the maximum variant allele frequencies ctDNA values showed strong association across different outcomes.

CONCLUSION

In this pooled analysis of five independent clinical trials, consistent and robust associations between reductions in ctDNA and outcomes were found across multiple end points assessed in patients with non-small-cell lung cancer treated with an ICI. Additional tumor types, stages, and drug classes should be included in future analyses to further validate this. CtDNA may serve as an important tool in clinical development and an early indicator of treatment benefit.

FDA Approval Summary: Ivosidenib for the Treatment of Patients with Advanced Unresectable or Metastatic, Chemotherapy Refractory Cholangiocarcinoma with an IDH1 Mutation

On August 25, 2021, the FDA approved ivosidenib for the treatment of adult patients with unresectable locally advanced or metastatic hepatocellular isocitrate dehydrogenase 1 (IDH1) mutated cholangiocarcinoma (CCA) as detected by an FDA-approved test with disease progression after 1 to 2 prior lines of systemic therapy for advanced disease. The approval was based on data from Study AG120-C-005 (ClarIDHy), a double-blind placebo-controlled trial that randomly allocated (2:1) patients to receive either ivosidenib or placebo. Independently assessed progression-free survival (PFS) was the primary endpoint. With a median follow-up of 6.9 months, the HR for PFS was 0.37 [95% confidence interval (CI), 0.25-0.54; P < 0.0001). Overall survival (OS) was the key secondary endpoint. At the final analysis of OS, with 70.5% of patients in the placebo arm receiving ivosidenib post disease progression, a non-statistically significant improvement in the ivosidenib arm with an HR = 0.79 (95% CI, 0.56-1.12) and median OS of 10.3 months (95% CI, 7.8-12.4) and 7.5 months (95% CI, 4.8-11.1) in the ivosidenib and placebo arms, respectively, were reported. Adverse reactions occurring in >20% of patients receiving ivosidenib were fatigue/asthenia, nausea, diarrhea, abdominal pain, ascites, vomiting, cough, and decreased appetite. Adverse reactions occurring in >20% of patients receiving placebo were fatigue/asthenia, nausea, abdominal pain, and vomiting. This is the first approval for the subset of patients with CCA harboring an IDH1 mutation.

Updated FDA pooled analysis of pain medication use in trial participants with HR+, HER2-negative metastatic breast cancer treated with endocrine therapy and a CDK 4/6 inhibitor

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Background: Pain medications (PMs) are commonly used to treat pain in patients with advanced or metastatic breast cancer (MBC). We previously reported an initial analysis of PM prescribing patterns in clinical trial participants with breast cancer receiving CDK 4/6 inhibitor (CDKI)-based treatment. We present an updated analysis here. Methods: We pooled data from 7 randomized controlled trials of CDKI + endocrine therapy (ET) in patients with HR+, HER2-negative MBC. All analyzed patients received at least 1 dose of CDKI/placebo+ET and a concomitant PM with a documented start date. Medications administered during hospitalizations were not included. We looked at PM use in all patients, patients who took PM only before or after the trial started, and those who took PM both before and during the trial. PMs were categorized as opioid (includes codeine-containing), NSAIDS, or other (i.e. bone-directed, antiepileptic, topical PMs). Results: 4200 patients enrolled across the 7 trials who received at least one dose of CDKI/placebo+ET (n = 2616 CDKI, n = 1548 placebo). Of these, 2881 took a PM at any time (n = 1774 CDKI, n = 1107 placebo). Of the 1774 patients who received CDKI+ET, 487 (27%) took at least one opioid and one NSAID at any time, 782 (44%) took at least one NSAID at any time but no opioids, 244 (14%) took at least one opioid at any time but no NSAIDs, and 261 (15%) took only PM that were not opioids or NSAIDs. Of the 1107 patients who received placebo+ET, 297 (27%) took at least one opioid and one NSAID at any time, 490 (44%) took at least one NSAID at any time but no opioids, 153 (14%) took at least one opioid at any time but no NSAIDS, and 167 (15%) took only PM that were not opioids or NSAIDs. Of the 2881 patients who took a PM at any time, 2038 patients (n = 1222 CDKI, n = 816 placebo) had documented start for their PM. Of these, 544 took PM only before the trial started (n = 334 CDKI, n = 210 placebo), 915 took a PM only during the trial (n = 551 CDKI, n = 364 placebo), and 579 took a PM both before and during the trial (n = 337 CDKI, n = 242 placebo). Overall, more patients took NSAIDs only compared to opioids only. Patient characteristics at baseline were balanced between the two arms. Conclusions: Overall, PM prescribing patterns were similar between the arms. NSAID use was higher than opiates in all groups. These findings are hypothesis generating and additional research is needed to determine the impact of PM on participants’ pain and physical function. Further research should include an understanding of the duration of PM needed in patients with MBC.

Association of progression-free survival and overall response rate with overall survival in first-line randomized trials of immune checkpoint inhibitor–based regimens for metastatic non–small cell lung cancer (NSCLC): An FDA pooled analysis

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Background: Overall Survival (OS) has represented the endpoint of choice to support approvals of Immune Checkpoint Inhibitors (ICIs) in first-line metastatic NSCLC. Despite continued interest in the use of earlier clinical endpoints as true surrogates for OS in this setting, the correlation of Progression-Free Survival (PFS) and Overall Response Rate (ORR) with OS remain an area of active investigation. We conducted a patient-level and trial-level pooled analysis of first-line randomized trials of ICI-based regimens to assess correlations of early clinical endpoints of PFS and ORR with OS in first-line metastatic NSCLC. Methods: The analysis included randomized trials comparing ICI-based regimens (anti-PD-(L)1 with or without anti-CTLA4 antibodies, with or without platinum-based chemotherapy) to platinum-based chemotherapy alone for the first-line treatment of patients with metastatic NSCLC that were submitted to the U.S. Food and Drug Administration between July 2016 to March 2021 to support a marketing application. Patient-level associations were estimated using Spearman (rs) correlation coefficients for PFS and OS, and Cox Proportional Hazards models in RECIST response-based subgroups for ORR and OS. At the trial level, associations were estimated using R2 coefficients from weighted linear regression models, using the log of hazard-ratio (HRs) for PFS and OS and log-odds ratio for ORR. Results: The pooled analysis included 13 trials enrolling 9,285 patients total. Seven trials compared ICIs combined with chemotherapy vs chemotherapy; 6 trials compared ICIs alone vs chemotherapy. Among all patients, the distribution of PD-L1 expression was 31%, 66%, and 32% for PD-L1 <1%, ≥1%, and ≥50%, respectively. The table shows the correlation coefficients for PFS and OS, and ORR and OS at the patient and trial levels. At the patient level, the OS HR comparing ICI-based regimens to chemotherapy was 0.54 (95% CI: 0.48, 0.61) for RECIST responders and 0.96 (95% CI: 0.90, 1.02) for non-responders. Conclusions: This pooled analysis did not indicate a strong correlation between endpoints of PFS and ORR with OS at the patient and trial levels in first-line randomized trials of ICI-based regimens for metastatic NSCLC, potentially because of use of subsequent therapies, cross-over to ICIs, and continuation of ICIs beyond progression. Future research will explore the correlation of alternative endpoints with OS, such as time to treatment discontinuation. Our analysis supports the continued importance of OS as an endpoint for first-line NSCLC trials of ICI-based regimens.[Table: see text]

Outcomes of anti–PD-(L)1 therapy with or without chemotherapy (chemo) for first-line (1L) treatment of advanced non–small cell lung cancer (NSCLC) with PD-L1 score ≥ 50%: FDA pooled analysis

9000

Background: FDA-approved 1L treatment options for patients with PD-L1-high advanced NSCLC (PD-L1 score ≥50%) include IO ± chemo (± anti-angiogenics) but it is unclear if chemo substantially improves efficacy outcomes when added to IO in this patient population. Methods: Data was pooled from 12 randomized controlled trials that investigated anti-PD-(L)1 regimens ± chemo for the 1L treatment of patients with advanced NSCLC. PD-L1 score was defined as the proportion of tumor cells stained by the assay and analysis was conducted for patients with tumor PD-L1 score ≥50%. OS, PFS, and ORR were compared between chemo-IO and IO alone via a pooled analysis. Median survival times were estimated using Kaplan-Meier methods. Hazard ratios were estimated using Cox proportional hazards models stratified by trial; odds ratios were estimated using a logistic regression model with trial as a covariate. All analyses were adjusted for age, sex, race, ECOG, histology and smoking status. Results: A total of 3,189 patients with NSCLC and PD-L1 score ≥50% were identified for this analysis. Baseline characteristics were: 38% ages 65-74 years and 11% ages ≥75 years; 69% male; 80% White; 66% ECOG ≥1; and 89% former/current smokers. Median OS in the pooled chemo-IO ( N=455) and IO-only ( N=1,298) arms was 25.0 vs 20.9 months (HR 0.82; 95% CI: 0.62, 1.08); median PFS was 9.6 vs 7.1 months, respectively (HR 0.69; 95% CI: 0.55, 0.87). ORR was higher with chemo-IO than with IO alone (61% vs 43%; Odds ratio 1.2, 95% CI: 1.1, 1.3). Conclusions: This exploratory, hypothesis-generating pooled analysis suggests that most subgroups of patients with advanced NSCLC with PD-L1 score ≥50% receiving FDA-approved chemo-IO regimens may have OS and PFS outcomes that are comparable with or better than IO-only regimens. Patients ≥75 years of age receiving chemo-IO may not have improved outcomes over IO. These results support shared decision-making that balances potential benefits and risks of adding chemo to IO regimens based on patient factors that may impact tolerability. [Table: see text]

Outcomes of first-line immune checkpoint inhibitors with or without chemotherapy according to KRAS mutational status and PD-L1 expression in patients with advanced NSCLC: FDA pooled analysis

9001

Background: While existing data suggest a detriment of immune checkpoint inhibitors (ICI) in other targetable mutations in non-small cell lung cancer (NSCLC), limited retrospective analyses suggest patients with Kirsten rat sarcoma oncogene ( KRAS)-mutated NSCLC benefit from ICI in the front-line (1L). To better define this benefit, pooled data from 12 registrational clinical trials investigating 1L ICI with or without chemotherapy (chemo) in patients with documented KRAS status (mutant or wildtype) was evaluated for efficacy of ICI+chemo, ICI alone, and chemo alone. Methods: Pooled data was evaluated for objective response rate (ORR) and overall survival (OS) by KRAS status (mutant, G12C, or wildtype). ORR and 95% confidence intervals (CI) were estimated using Clopper-Pearson method; median OS was estimated using Kaplan-Meier methods. Subgroup analyses were performed using Cox model stratified by KRAS status and PD-L1 status (Positive (combined positive score (CPS) ≥1), Negative (CPS<1), High (CPS≥50), Low (CPS<50)). Results: KRAS mutational status was reported in 1430 patients (61% wildtype, 39% mutated). KRAS G12C was reported in 11% of patients with a KRAS mutation (157/555). Demographics were similar between KRAS mutated, G12C, and wildtype patients. Amongst all patients, 60% were male, 89% white, 60% positive PD-L1, 67% former or current smokers. Table 1 shows outcomes of chemo+ICI, ICI alone, and chemo alone in each population. Conclusions: This retrospective, pooled analysis suggests that patients with KRAS-mutated NSCLC benefit from 1L chemo-ICI similarly to those with KRAS wild-type NSCLC, and should receive combination therapy upfront. Patients with KRAS-mutated NSCLC derived the greatest benefit from the combination of chemo-ICI as compared to ICI or chemo alone. The small number of patients with documented KRAS G12C mutation limits interpretation of the data for this subgroup. Clinical trials investigating targeted therapies for KRAS-mutated NSCLC in the 1L should include a chemo-ICI comparator arm. [Table: see text]

FDA analysis of expanded access use in pediatric patients from 2015 to 2020

1529

Background: Expanded Access is a regulatory mechanism that enables patients with a life-threatening condition or serious disease to receive treatment with an investigational drug outside of a clinical trial when no comparable or satisfactory alternative options are available. FDA has decades of experience with expanded access, but little has been reported about its use in pediatric cancer patients. Methods: FDA’s central electronic database was queried for single-patient investigational new drug (spIND) applications submitted to the Office of Oncologic Diseases between January 2015 through December 2020. Data collection included IND receipt date, IND type/status, drug name, and patient demographics. Duplicate or exempt INDs, those cancelled by the physician-sponsor before initiating therapy, and those requested for indications that occur almost exclusively in adults (e.g. lung cancer) or were missing patient age were excluded. Results: Of 2,901 unique spINDs granted, 534 (18%) were for patients less than 18 years of age. The pediatric population was 57% male, median age 6.0 years (range 0.1 to 17); race/ethnicity were reported in <1%. Patients were treated in 132 zip codes across 39 states; one-quarter of submissions were from 5 large academic hospitals. Central nervous system tumors were the most common indication (Table 1). A total of 98 unique drugs were requested, with 1 to 73 spINDs for each drug; approximately 50% were for tyrosine kinase inhibitors, 25% for other small molecules, and the remainder for immunotherapies and other drug types. Median time for FDA to grant was 1 day. Follow-up information was provided for 75% (annual report or withdrawal letter); 1/3 were withdrawn within 1 year. Over the last 2 years, utilization of the program increased by 120%. Conclusions: While approximately 1% of all cancers per year are diagnosed in children under 17 years of age, 18% of spINDs over the last five years were for pediatric patients. Although utilization of this program for children is robust, efforts are needed to assess its impact on patient outcomes and ensure its availability to patients, families, and institutions more widely. These data highlight interest within the pediatric oncology community in accessing innovative therapies, which supports early investigation of promising new drugs in children.[Table: see text]

US Food and Drug Administration Analysis of Patient-Reported Diarrhea and Its Impact on Function and Quality of Life in Patients Receiving Treatment for Breast Cancer

OBJECTIVES

Many trials conclude "no clinically meaningful detriment" to health-related quality of life (HRQL) or function between arms, even when notable differential toxicity is observed. Mean change from baseline analyses of function or HRQL can possibly obscure important change in subgroups experiencing symptomatic toxicity. We evaluate the impact of diarrhea, a key treatment arm toxicity, on patient-reported HRQL and functioning in clinical trials submitted to US Food and Drug Administration.

METHODS

This study used 4 randomized, breast cancer trials (adjuvant to late-line metastatic) as case examples. Diarrhea, physical functioning (PF), and global health status and quality of life (GHS/QoL) from the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-C30 were analyzed at baseline and approximately 3 and 6 months.

RESULTS

Generally, patients reporting very much diarrhea at months 3 and 6 had worse PF (9-19 points lower) and GHS/QoL (16-19 points lower) than patients reporting no diarrhea regardless of treatment arm. In the change from baseline analysis, patients reporting very much diarrhea also experienced a greater decrease in PF (6-13 points) and GHS/QoL (6-16 points) versus patients reporting no diarrhea in both arms.

CONCLUSIONS

In trials with moderate to large differences in symptomatic toxicity by arm, reporting "no meaningful difference in functioning and HRQL between arms" based on mean change from baseline analysis is insufficient and may obscure important impacts on subgroups experiencing symptomatic adverse events. Additional exploratory analyses with simple data visualizations evaluating functioning or HRQL in patient subgroups experiencing expected symptomatic toxicities can further inform the safety and tolerability of an investigational agent.

In search of autophagy biomarkers in breast cancer: Receptor status and drug agnostic transcriptional changes during autophagy flux in cell lines

Autophagy drives drug resistance and drug-induced cancer cell cytotoxicity. Targeting the autophagy process could greatly improve chemotherapy outcomes. The discovery of specific inhibitors or activators has been hindered by challenges with reliably measuring autophagy levels in a clinical setting. We investigated drug-induced autophagy in breast cancer cell lines with differing ER/PR/Her2 receptor status by exposing them to known but divergent autophagy inducers each with a unique molecular target, tamoxifen, trastuzumab, bortezomib or rapamycin. Differential gene expression analysis from total RNA extracted during the earliest sign of autophagy flux showed both cell- and drug-specific changes. We analyzed the list of differentially expressed genes to find a common, cell- and drug-agnostic autophagy signature. Twelve mRNAs were significantly modulated by all the drugs and 11 were orthogonally verified with Q-RT-PCR (Klhl24, Hbp1, Crebrf, Ypel2, Fbxo32, Gdf15, Cdc25a, Ddit4, Psat1, Cd22, Ypel3). The drug agnostic mRNA signature was similarly induced by a mitochondrially targeted agent, MitoQ. In-silico analysis on the KM-plotter cancer database showed that the levels of these mRNAs are detectable in human samples and associated with breast cancer prognosis outcomes of Relapse-Free Survival in all patients (RSF), Overall Survival in all patients (OS), and Relapse-Free Survival in ER⁺ Patients (RSF ER⁺). High levels of Klhl24, Hbp1, Crebrf, Ypel2, CD22 and Ypel3 were correlated with better outcomes, whereas lower levels of Gdf15, Cdc25a, Ddit4 and Psat1 were associated with better prognosis in breast cancer patients. This gene signature uncovers candidate autophagy biomarkers that could be tested during preclinical and clinical studies to monitor the autophagy process.

Abstract P2-11-05: Generating real-world external comparators for randomized clinical trials (RCTs) in metastatic breast cancer (mBC) using electronic health records (EHRs)

Objectives: Real-world data (RWD) from the routine care of patients with cancer captured through EHRs is a valuable resource for research. Understanding the relationship between characteristics and outcomes of patients treated in the real world and those treated in clinical trials is essential to produce evaluable trial-like populations using RWD in oncology for research and regulatory purposes. Methods: This study used: a) RWD from the Flatiron Health EHR-derived, de-identified, longitudinal database (comprising patient-level structured and unstructured data, curated via technology-enabled abstraction selected from approximately 280 US cancer clinics [~800 sites of care]) and b) patient-level data from three completed RCTs (PALOMA-2, MONALEESA-2, and MONARCH-3) including patients with previously untreated hormone receptor positive (HR+), HER2/neu negative (HER2-) mBC, then separately pooled across the trials into two treatment groups, patients who received aromatase inhibitor monotherapy (AI) or a CDK4/6 inhibitor + AI. Key eligibility criteria were similar across the RCTs and were used to select a real world external cohort (rwEC) initiating AI monotherapy on or prior to 11 Nov 2015 (end of MONARCH-3 enrollment period). Patients from the rwEC were matched separately to the control arm and experimental arm patients from the pooled RCT using propensity score method (PSM). The propensity score was estimated by a logistic regression using baseline covariates of age, race, site of disease (visceral, non-visceral), Eastern Cooperative Oncology Group Performance Status (ECOG PS) (0, 1), and metastatic disease (recurrent, new). The matching ratio was 1:1 without replacement with calipers. Covariate balance was measured by the absolute standardized mean difference (ASMD). Due to the high percentage of missing ECOG PS data, matching was repeated 100 times with imputed ECOG PS. The impact of including additional key covariates for propensity matching such as number of disease sites, bone-only disease, and prior endocrine therapy was assessed. Results: There were 1326 patients with HR+, HER2- mBC selected from the EHR-derived database who received first-line AI therapy and 1827 patients randomized in the RCTs (1106 and 721 patients for experimental and control arms, respectively). With 100 matching iterations, 563 rwEC patients on average (range, 547-572) were matched to the RCTs control arm, and 753 rwEC patients on average (range: 741-761) were matched to the RCTs experimental arm. Prior to matching, the ASMD varied widely across all prespecified baseline covariates (4.3 for the rwEC vs. RCTs control arm, 2.6 for the rwEC vs. RCTs experimental arm). After matching was performed, across all baseline covariates used in the PSM, the ASMD was reduced to be under 0.12 for the rwEC vs. RCTs control arm, and under 0.2 for the rwEC vs. RCTs experimental arm in more than 90% of the matching iterations. Analyses looking at the additional baseline covariates to the propensity matching resulted in similar ASMDs. Conclusions: EHR-derived RWD can be used to generate a cohort of patients with similar baseline characteristics to those treated on RCT. The next step in our trial emulation framework is to analyze the comparability of outcomes between these two matched cohorts.

Citation Format: Laleh Amiri-Kordestani, Xin Gao, Shrujal Baxi, Erik Bloomquist, Jonathan Bryan, Lynn Howie, Catherine Keane, Paul G. Kluetz, Christy Osgood, Prashni Paliwal, Donna R. Rivera, James Roose, Julie Schneider, Harpreet Singh, Shenghui Tang, Lijun Zhang, Julia A. Beaver. Generating real-world external comparators for randomized clinical trials (RCTs) in metastatic breast cancer (mBC) using electronic health records (EHRs) [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-11-05.

Floor and ceiling effects in the EORTC QLQ-C30 Physical Functioning Subscale among patients with advanced or metastatic breast cancer

BACKGROUND

The European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 Physical Functioning subscale is a widely used patient-reported outcome measure that quantifies cancer patients' physical functioning. Strong floor/ceiling effects can affect a scale's sensitivity to change. The aim of this study was to characterize floor/ceiling effects of the physical functioning domain in patients with advanced/metastatic breast cancer enrolled in commercial clinical trials and a community-based trial.

METHODS

The clinical trial cohort comprised patients from 5 registrational trials submitted to the Food and Drug Administration for review (2010-2017). The community cohort comprised a subgroup of patients from the Alliance Patient Reported Outcomes to Enhance Cancer Treatment (PRO-TECT) trial. The distribution of patient responses to Physical Functioning items and the summed score were assessed at the baseline and 3-month follow-up for both cohorts. Descriptive statistics were used to determine floor/ceiling effects at the item and scale levels.

RESULTS

The clinical trial cohort and the community cohort consisted of 2407 and 178 patients, respectively. Twenty-four percent or more of the respondents reported "not at all" for having trouble/needing help with each Physical Functioning item across both cohorts and measurement time points. Fourteen to twenty percent of the patients scored perfectly (100 of 100) on the Physical Functioning subscale summary measure (where higher scores indicated better physical functioning) across both cohorts and time points.

CONCLUSIONS

Minor floor effects and notable ceiling effects were found at the item and scale levels of the Physical Functioning subscale, regardless of cohort, and this creates some uncertainty about its ability to detect changes in physical functioning among high-functioning patients. Investigators may consider adding additional high-functioning items from the EORTC's item library to more accurately describe the impact of anticancer treatment on patients' physical functioning.

Abstract P5-19-02: Methodological approaches to the use of real-world data(RWD) for medical products to treat breast cancer: An FDA oncology center of excellence evaluation of RWD submissions

Background: Aligning with 21st Century Cures legislation, FDA is exploring various methodologies to advance appropriate uses of Real-World Data (RWD) to generate Real-World Evidence (RWE). Inclusion of RWD to support regulatory decision making has increased in oncology, and this review specifically focused on characterizing RWD submissions for the treatment of breast cancer (BC). Methods: A systematic search was conducted using internal FDA databases to identify RWD submissions from 2010 to 2020. Search terms included real world evidence, real world data, cancer registry, administrative claims, external control arm, and other terms relevant to RWD/RWE. Relevant regulatory submissions were reviewed, pre-defined common data elements were extracted, and the subset applicable to breast cancer was evaluated. Results: Of 142 regulatory submissions that included RWD, 6 specifically evaluated BC indications and 3 were for solid tumor indications with potential applicability to BC, corresponding to 4 new molecular entities. Regulatory objectives included support for labeling changes including efficacy (expanded indications), safety , and dose or administration modifications. The most commonly used design was a retrospective observational study with structured electronic health records (EHRs) or medical claims data, supplemented by unstructured data from medical records or chart review for missing data elements. Four of the 6 BC submissions were significantly limited by a high degree of data missingness and confounding, with some studies including key covariates that were missing in &gt;50% of the structured data. RWD was used to provide contextual evidence for label expansion for populations not included or adequately represented in the registration trial. Of note, for the application expanding the label to include treatment of male BC, the regulatory decision was primarily based on clinical trial data. The primary rwEndpoints submitted were overall survival (rwOS), progression free survival (rwPFS), response rate (rwORR) and time to next treatment (TTNT). Safety outcomes were investigated in all but 1 of the studies, most commonly as a secondary RWD endpoint. Conclusion: In our review of regulatory submissions relevant to breast cancer therapies, RWD has largely been used to contextualize and complement prospective clinical trial data. Evaluating that selected RWD is fit for purpose to address the regulatory objective(s) and all analytical plans are prespecified allows for robust data characterization, and appropriate evaluation. Data relevance (availability of key variables) along with reliability assessment which includes evaluating data for completeness, consistency, and trends over time are necessary for the rigorous evaluation of RWE in drug development. Data missingness is a key issue in RWD, especially when structured data are not available and specific variables are unlikely to be captured in a reliable way in the unstructured data or further validation is not feasible. To optimize RWD as evidence for specific patient populations, attention to the proportion of patients excluded is necessary to avoid concerns regarding the generalizability of the data. Careful selection of rwEndpoints must be aligned with the study design and objective, include data such as prior, concomitant and subsequent anti-cancer treatments, and the ability for outcome validation to be methodologically appropriate. When contemplating a regulatory submission using RWD, early consultation with the appropriate FDA review division can provide additional feedback on the appropriate use of RWD or pragmatic designs.

Citation Format: Melanie E Royce, Jennifer J. Lee, Christy L. Osgood, Laleh Amiri-Kordestani, Julia A. Beaver, Paul G. Kluetz, Donna R. Rivera. Methodological approaches to the use of real-world data(RWD) for medical products to treat breast cancer: An FDA oncology center of excellence evaluation of RWD submissions [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-19-02.

Association of Radiation Therapy With Risk of Adverse Events in Patients Receiving Immunotherapy: A Pooled Analysis of Trials in the US Food and Drug Administration Database

Importance

Immune checkpoint inhibitors (ICIs) and radiation therapy (RT) are widely used to treat various cancers, but little data are available to guide clinicians on ICI use sequentially with RT.

Objective

To assess whether there is an increased risk of serious adverse events (AEs) associated with RT given within 90 days prior to an ICI.

Design, Setting, and Participants

Individual patient data were pooled from 68 prospective trials of ICIs submitted in initial or supplemental licensing applications in the US Food and Drug Administration (FDA) databases through December 2019. Two cohorts were generated: (1) patients who received RT within the 90 days prior to beginning ICI therapy and (2) those who did not receive RT within the 90 days prior to beginning ICI therapy, and AE frequencies were determined. A 1:1 propensity score-matched analysis was performed.

Interventions

All patients received an ICI (atezolizumab, avelumab, cemiplimab, durvalumab, ipilimumab, nivolumab, or pembrolizumab); 1733 received RT within the 90 days prior to starting ICI therapy, and 13 956 did not.

Main Outcomes and Measures

The primary outcome was frequency and severity of AEs. Incidence of AEs was compared descriptively between participants who did vs did not receive RT in the propensity score-matched set. Because all analyses are exploratory (ie, not preplanned and no alpha allocated), assessment for statistical significance of the differences between groups was not considered appropriate.

Results

A total of 25 469 patients were identified; 8634 were excluded because they lacked comparators who had received RT (n = 976), did not receive an ICI (n = 4949), received RT outside of the target window (n = 2338), or had missing data in 1 or more variables used in the propensity analysis (n = 371), leaving 16 835 patients included in the analysis. The majority were younger than 65 years (9447 [56.1%]), male (10 459 [62.1%]), and White (13 422 [79.7%]). Patients receiving RT had generally similar rates of AEs overall to those patients who did not receive RT. The average absolute difference in rates across the AEs was 1.2%, and the difference ranged from 0% for neurologic AEs to 8% for fatigue. No difference in grade 3 to 4 AEs was observed between the 2 groups (absolute difference ranged from 0.01% to 2%). These findings persisted after propensity score matching.

Conclusions and Relevance

In this pooled analysis, administration of an ICI within 90 days following RT did not appear to be associated with an increased risk of serious AEs. Thus, it would appear to be safe to administer an ICI within 90 days of receiving RT. These findings should be confirmed in future prospective trials.

FDA Approval Summary: Abemaciclib With Endocrine Therapy for High-Risk Early Breast Cancer

PURPOSE

The US Food and Drug Administration approved abemaciclib in combination with endocrine therapy (ET) for the adjuvant treatment of adult patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative, node-positive, early breast cancer (EBC) at high risk of recurrence and a Ki-67 score ≥ 20%.

PATIENTS AND METHODS

The approval was based on monarchE, a phase III, open-label, 2-cohort, multicenter trial of patients with EBC randomly assigned to receive abemaciclib plus ET (n = 2,808) or ET alone (n = 2,829). Abemaciclib was given at 150 mg orally twice daily for 2 years.

RESULTS

Invasive disease-free survival (IDFS) in the intent-to-treat population was statistically significant at the second IDFS interim analysis (IA; March 2020; hazard ratio [HR; 95% CI], 0.747 [0.598 to 0.932]; P = .0096); however, only 12.5% of patients had completed adjuvant therapy, and the HR for overall survival (OS) was > 1. A prespecified, controlled analysis of IDFS in patients with Ki-67 ≥ 20% in cohort 1 was statistically significant at the final IDFS analysis (July 2020; HR [95% CI], 0.643 [0.475 to 0.872]; P = .0042). At the first OS IA (April 2021), the majority of patients had completed adjuvant therapy, IDFS remained consistent, and potential detriment in OS was not observed for this subgroup (HR [95% CI], 0.767 [0.511 to 1.152]). The HR for OS in the intent-to-treat population at OS IA remained > 1 (HR [95% CI], 1.091 [0.818 to 1.455]). More patients in the abemaciclib plus ET arm experienced treatment emergent adverse events (all grades 98.4% v 88.8%, grade 3 ≥ 49.7% v 16.3%).

CONCLUSION

The approval of abemaciclib in adjuvant EBC was limited to patients with high risk of recurrence and Ki-67 ≥ 20%, given their favorable benefit:risk with a statistically significant IDFS advantage and no observed detriment on survival.

FDA Approval Summary: Margetuximab plus Chemotherapy for Advanced or Metastatic HER2-Positive Breast Cancer

On December 16, 2020, the FDA granted regular approval to margetuximab-cmkb (MARGENZA), in combination with chemotherapy, for the treatment of adult patients with HER2-positive (HER2⁺) metastatic breast cancer who have received two or more prior anti-HER2 regimens, at least one of which was for metastatic disease. Approval was based on data from SOPHIA, a multicenter, randomized, open-label, active controlled study comparing margetuximab with trastuzumab, in combination with chemotherapy. The primary efficacy endpoint was progression-free survival (PFS) by blinded independent central review. SOPHIA demonstrated a 0.9-month difference in median PFS between the two treatment arms [5.8 vs. 4.9 months, respectively; stratified HR, 0.76 (95% confidence interval: 0.59-0.98; P = 0.0334)]. Overall survival (OS) was immature at the data cut-off date of September 10, 2019. Infusion-related reactions (IRR) are an important safety signal associated with margetuximab plus chemotherapy. In SOPHIA, 13% of patients treated with margetuximab plus chemotherapy reported IRRs, of which 1.5% were grade 3. The most commonly reported adverse drug reactions (>10%) with margetuximab in combination with chemotherapy were fatigue/asthenia, nausea, diarrhea, vomiting, constipation, headache, pyrexia, alopecia, abdominal pain, peripheral neuropathy, arthralgia/myalgia, cough, decreased appetite, dyspnea, IRR, palmar-plantar erythrodysesthesia, and extremity pain. Overall, the favorable risk-benefit profile for margetuximab when added to chemotherapy supported its approval for the intended indication.

FDA Approval Summary: Sotorasib for KRAS G12C-Mutated Metastatic NSCLC

On May 28, 2021, the FDA granted accelerated approval to sotorasib (Lumakras, Amgen) for the treatment of adults with advanced non-small cell lung cancer (NSCLC) with a Kirsten rat sarcoma proto-oncogene (KRAS) G12C mutation who have received at least one prior systemic therapy. The approval was based on CodeBreaK 100 (Study 20170543), a dose-escalation and dose-expansion trial in patients with an advanced, KRAS G12C-mutated, solid tumor. The overall response rate (ORR) observed in patients with KRAS G12C-mutated NSCLC treated with sotorasib (n = 124) was 36% [95% confidence interval (CI), 28-45]. The median duration of response was 10.0 months (95% CI, 6.9-not estimable). The most common adverse reactions (≥20%) were diarrhea, musculoskeletal pain, nausea, fatigue, hepatotoxicity, and cough. This is the first approval of a targeted therapy for KRAS G12C-mutated NSCLC. Because of pharmacokinetic data and ORRs of patient cohorts who took sotorasib at lower doses in the dose-escalation portion of CodeBreaK 100, a dose comparison study is being conducted as a post-marketing requirement.

U.S. FDA Drug Approvals for Gynecological Malignancies: A Decade in Review

Over the last decade, there has been tremendous progress in the treatment of patients with gynecologic cancers with a changing therapy landscape. This summary provides an overview of U.S. Food and Drug Administration (FDA) approvals for gynecologic cancers from 2010 to 2020, totaling 17 new indications. For each of the approved indications, endpoints, trial design, results, and regulatory considerations are outlined. Among these 17 indications, six received accelerated approval (AA) and 11 received regular approval (RA). As of September 2021, of the six AA, three have subsequently demonstrated clinical benefit resulting in conversion to RA and the remaining three have ongoing clinical trials that have not yet reported results. Approval decisions for these 17 indications were supported by primary efficacy endpoints of progression-free survival (n = 10), objective response rate (n = 6), and overall survival (n = 1) and showed a favorable benefit-risk profile. Among the 17 indications, 15 received priority review and three applications participated in one or more novel Oncology Center of Excellence initiatives, including Real Time Oncology Review, Assessment Aid, and Project Orbis. Current FDA thinking on drug development opportunities and regulatory initiatives currently under way will be discussed.

U.S. FDA Drug Approvals for Breast Cancer - A Decade in Review

Over the last decade, the treatment of patients with breast cancer has been greatly impacted by the approval of multiple drugs and indications. This summary describes 30 FDA approvals of treatments for breast cancer from 2010 to 2020. The trial design endpoints, results, and regulatory considerations are described for each approved indication. Of the 30 indications, 23 (76.6%) received regular and 7 (23.3%) received accelerated approval. Twenty-six approvals were granted in metastatic breast cancer (MBC) and four in early breast cancer. Approval decisions for the 26 MBC indications were initially supported by progression-free survival (PFS) in 21 (80.8%), overall survival (OS) or a combination of OS and PFS in two (7.7%), and objective response rate (ORR) in three (11.5%). The four approvals in early breast cancer utilized pathologic complete response (pCR) in one (25%) and invasive disease-free survival (iDFS) in three (75%) trials. Among the 30 indications, 22 received priority review, seven were granted Breakthrough Therapy Designation, and 10 applications participated in one or more pilot Oncology Center of Excellence regulatory review initiatives, including Real Time Oncology Review, Assessment Aid, and Project Orbis. FDA initiatives to advance breast cancer drug development are also described.

The FDA Oncology Center of Excellence Scientific Collaborative: Charting a Course for Applied Regulatory Science Research in Oncology

The FDA Oncology Center of Excellence (OCE) is a leader within the agency in scientific outreach activities and regulatory science research. On the basis of analysis of scientific workshops, internal meetings, and publications, the OCE identified nine scientific priority areas and one cross-cutting area of high interest for collaboration with external researchers. This article describes the process for identifying these scientific interest areas and highlights funded and unfunded opportunities for external researchers to work with FDA staff on critical regulatory science challenges.

Trends in diagnosis and treatment of early breast cancer (eBC) in the United States (US) during the COVID-19 era

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Background: Recent studies have demonstrated a decline in cancer screening and diagnosis during the COVID-19 pandemic. This study explored trends in the diagnosis and management of eBC at a sample of cancer clinics across the US early on in the pandemic. Methods: Patients were selected from the Flatiron Health Research Database (FHRD), an electronic health record-derived de-identified database comprising approximately 280 US cancer clinics (̃800 sites of care). Eligible patients had an ICD code for breast cancer, at least two clinical encounters, and a confirmed eBC (Stage I-III) diagnosis from unstructured documents. Patients were selected into two cohorts based on diagnosis date: a) COVID-19 era cohort diagnosed between February 1, 2020 through June 30, 2020 and b) pre-COVID-19 era cohort diagnosed from February 1, 2019 through June 30, 2019. Descriptive statistics were used to assess diagnosis trends in each time frame. Initial treatment received following eBC diagnosis was categorized as surgery, radiation or systemic therapy and was compared between the two cohorts. Initial treatment modalities for each cohort were further stratified by clinical stage and biomarker subtype (HER2+, HR+/HER2-, triple negative [TN] or unknown). Results: A total of 278 and 253 patients were selected for the pre-COVID-19 era and COVID-19 era cohorts, with a median age at diagnosis of 65 and 64 years, respectively. A 35% decrease in the number of eBC diagnoses was observed in April/May 2020 compared to March 2020, yet this reduction in diagnoses was not observed during the equivalent months in the pre-COVID-19 era cohort. Compared to the pre-COVID-19 era, a greater proportion of patients diagnosed with eBC during the COVID-19 era initiated systemic therapy as their first treatment modality (16.5% vs 29.6%) including patients with HER2+ (27.5% vs. 60%), HR+/HER2- (13.5% vs. 24.9%) and TN (30.8% vs. 40.0%) disease. This trend was observed in patients with stage I (11.7% vs. 24.1%) or II (55.9% vs. 73.0%) but not in patients with stage III (81.2% vs. 77.3%) eBC. Notably, among patients with HR+/HER2- eBC who received systemic therapy as their first treatment, endocrine therapy was most commonly used in keeping with recent recommendations from professional societies due to COVID-related anticipated surgical delays. Conclusions: This study demonstrates that COVID-19 was associated with a decreased incidence of eBC which could be, at least in part, attributed to previously reported delays in routine screening and pandemic healthcare utilization. Further efforts are required to understand who was affected by these delays and the impact on cancer outcomes. Follow-up data are needed to understand if the observed trends in cancer screening and treatment persist and their impact on long-term cancer outcomes.

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.

FDA Approval Summary: Nivolumab in Combination with Ipilimumab for the Treatment of Unresectable Malignant Pleural Mesothelioma

On October 2, 2020, FDA approved nivolumab with ipilimumab as first-line treatment for adult patients with unresectable malignant pleural mesothelioma (MPM). The approval was based on results from Study CA209743 (CHECKMATE-743), an open-label trial of patients with MPM randomized to receive nivolumab and ipilimumab for up to 2 years (n = 303) or six cycles of chemotherapy with cisplatin or carboplatin plus pemetrexed (n = 302). Overall survival (OS) was improved for patients who received nivolumab and ipilimumab, with a median OS of 18.1 months [95% confidence interval (CI), 16.8-21.5] compared with 14.1 months (95% CI: 12.5-16.2; HR, 0.74; 95% CI, 0.61-0.89; P = 0.002), for patients who received chemotherapy. The magnitude of benefit was larger for patients with non-epithelioid versus epithelioid histology. Additional clinical pharmacology data support an alternative dosing regimen of nivolumab than evaluated in the trial, which will reduce the number of required treatment visits. This application was reviewed under FDA's Project Orbis, in collaboration with Australia's Therapeutic Goods Administration, Switzerland's Swissmedic, Health Canada, and Brazil's National Health Surveillance Agency or ANVISA (Agência Nacional de Vigilância Sanitária). Nivolumab and ipilimumab is the first drug regimen approved by FDA for MPM since 2004.

FDA Approval Summary: Tivozanib for Relapsed or Refractory Renal Cell Carcinoma

On March 10, 2021, the FDA granted regular approval to tivozanib for treatment of patients with relapsed or refractory (R/R) advanced renal cell carcinoma (RCC) following two or more prior systemic therapies. Approval was based on the TIVO-3 study, a randomized trial of tivozanib versus sorafenib in patients with R/R advanced RCC. In TIVO-3, patients were randomized to receive either tivozanib 1.34 mg orally once daily for 21 consecutive days of every 28-day cycle or sorafenib 400 mg orally twice daily continuously. The primary endpoint was progression-free survival (PFS) per RECIST v1.1. Tivozanib demonstrated efficacy compared with sorafenib with an improvement in PFS [HR, 0.73; 95% confidence interval (CI), 0.56-0.95; P = 0.016]. The estimated median PFS was 5.6 months and 3.9 months in the tivozanib and sorafenib arms, respectively. There was no evidence of a detrimental effect on overall survival: HR, 0.97 (95% CI, 0.75-1.24). The most common grade 3 to 4 adverse reaction on the tivozanib arm was hypertension (24%). Compared with sorafenib, tivozanib was associated with lower rates of grade 3 to 4 diarrhea, rash, and palmar-plantar erythrodysesthesia. Patients receiving tivozanib in TIVO-3 had lower rates of dose reduction, interruption, or permanent discontinuation than those receiving sorafenib.