A Real-World Study of Patient Characteristics and Clinical Outcomes in EGFR Mutated Lung Cancer Treated with First-Line Osimertinib: Expanding the FLAURA Trial Results into Routine Clinical Practice.

Osimertinib is a tyrosine kinase inhibitor of the epidermal growth factor receptor (EGFR) that is used for first-line therapy in EGFR mutated non-small cell lung cancer (NSCLC) based on the results of the randomized FLAURA trial (ClinicalTrials.gov number NCT02296125). We performed a retrospective analysis of baseline characteristics and clinical outcomes in 56 real-world patients treated with osimertinib. In total, 45% of patients were determined to be FLAURA-eligible and 55% were FLAURA-ineligible based on the published inclusion/exclusion criteria of the aforementioned trial. For clinical outcomes, the median osimertinib time to treatment discontinuation (TTD) for all patients was 16.9 months (95% CI: 12.6-35.1), whereas the median TTD was 31.1 months (95% CI: 14.9-not reached) in the FLAURA-eligible cohort and the median TTD was 12.2 months (95% CI: 8.1-34.6 months) in the FLAURA-ineligible cohort. Re-biopsy at acquired resistance disclosed both on- and off-target mechanisms. The most common therapies following osimertinib included local therapies followed by post-progression osimertinib, platinum-doublet chemotherapy with or without osimertinib, and osimertinib combinatory targeted therapies. The median overall survival for all patients was 32.0 months (95% CI: 15.7-not reached), the median survival was not reached for the FLAURA-eligible cohort, and it was 16.5 months for the FLAURA-ineligible cohort. Our data support the use of osimertinib in real-word settings and highlight the need for designing registration trials that are more inclusive of patient/disease characteristics seen in routine clinical practice. It is yet to be determined if the use of evolving first-line EGFR inhibitor combination strategies (either platinum-doublet chemotherapy plus osimertinib or amivantamab plus lazertinib) will similarly translate from clinical trials to real-word settings.

The Impact of On-Target Resistance Mediated by EGFR-T790M or EGFR-C797S on EGFR Exon 20 Insertion Mutation Active Tyrosine Kinase Inhibitors.

Introduction: Mechanisms of resistance to EGFR exon 20 insertion mutation active inhibitors have not been extensively studied in either robust preclinical models or patient-derived rebiopsy specimens. We sought to characterize on-target resistance mutations identified in EGFR exon 20 insertion-mutated lung cancers treated with mobocertinib or poziotinib and evaluate whether these mutations would or would not have cross-resistance to next-generation inhibitors zipalertinib, furmonertinib, and sunvozertinib. Methods: We identified mechanisms of resistance to EGFR exon 20 insertion mutation active inhibitors and then used preclinical models of EGFR exon 20 insertion mutations (A767_V769dupASV, D770_N771insSVD, V773_C774insH) plus common EGFR mutants to probe inhibitors in the absence/presence of EGFR-T790M or EGFR-C797S. Results: Mobocertinib had a favorable therapeutic window in relation to EGFR wild type for EGFR exon 20 insertion mutants, but the addition of EGFR-T790M or EGFR-C797S negated the observed window. Zipalertinib had a favorable therapeutic window for cells driven by EGFR-A767_V769dupASV or EGFR-D770_N771insSVD in the presence or absence of EGFR-T790M. Furmonertinib and sunvozertinib had the most favorable therapeutic windows in the presence or absence of EGFR-T790M in all cells tested. EGFR-C797S in cis to all EGFR mutations evaluated generated dependent cells that were resistant to the covalent EGFR tyrosine kinase inhibitors mobocertinib, zipalertinib, furmonertinib, sunvozertinib, poziotinib, and osimertinib. Conclusions: This report highlights that poziotinib and mobocertinib are susceptible to on-target resistance mediated by EGFR-T790M or -C797S in the background of the most prevalent EGFR exon 20 insertion mutations. Furmonertinib, sunvozertinib, and to a less extent zipalertinib can overcome EGFR-T790M compound mutants, whereas EGFR-C797S leads to covalent inhibitor cross-resistance-robust data that support the limitations of mobocertinib and should further spawn the development of next-generation covalent and reversible EGFR exon 20 insertion mutation active inhibitors with favorable therapeutic windows that are less vulnerable to on-target resistance.

Disparities in outcomes between Black and White patients in North America with thoracic malignancies and COVID-19 infection (TERAVOLT).

BACKGROUND: Patients with thoracic malignancies who develop COVID-19 infection have a higher hospitalization rate compared to the general population and to those with other cancer types, but how this outcome differs by race and ethnicity is relatively understudied. METHODS: The TERAVOLT database is an international, multi-center repository of cross-sectional and longitudinal data studying the impact of COVID-19 on individuals with thoracic malignancies. Patients from North America with thoracic malignancies and confirmed COVID-19 infection were included for this analysis of racial and ethnic disparities. Patients with missing race data or races and ethnicities with fewer than 50 patients were excluded from analysis. Multivariable analyses for endpoints of hospitalization and death were performed on these 471 patients. RESULTS: Of the 471 patients, 73% were White and 27% were Black. The majority (90%) were non-Hispanic ethnicity, 5% were Hispanic, and 4% were missing ethnicity data. Black patients were more likely to have an Eastern Cooperative Oncology Group (ECOG) Performance Status ≥ 2 (p-value = 0.04). On multivariable analysis, Black patients were more likely than White patients to require hospitalization (Odds Ratio (OR): 1.69, 95% CI: 1.01-2.83, p-value = 0.044). These differences remained across different waves of the pandemic. However, no statistically significant difference in mortality was found between Black and White patients (OR 1.29, 95% CI: 0.69-2.40, p-value = 0.408). CONCLUSIONS: Black patients with thoracic malignancies who acquire COVID-19 infection are at a significantly higher risk of hospitalization compared to White patients, but there is no significant difference in mortality. The underlying drivers of racial disparity among patients with thoracic malignancies and COVID-19 infection require ongoing investigation.

EGFR Tyrosine Kinase Inhibitors for the Treatment of Metastatic Non-Small Cell Lung Cancer Harboring Uncommon EGFR Mutations: A Podcast.

Supplementary file1 (MP4 21169 KB).

EGFR exon 20 insertion mutations and ERBB2 mutations in lung cancer: a narrative review on approved targeted therapies from oral kinase inhibitors to antibody-drug conjugates.

Background and Objective: This review will provide an overview of EGFR and ERBB2 mutations in non-small-cell lung cancer (NSCLC) with a focus on recent clinical approvals. Methods: We obtained data from the literature in accordance with narrative review reporting guidelines. Key Content and Findings: EGFR mutations are present in up to 15-20% of all NSCLCs; amongst these, 10% correspond to kinase domain insertions in exon 20. Structurally similar, ERBB2 (HER2) mutations occurs in 1-4% of NSCLCs, mostly consisting of insertions or point mutations. The majority of EGFR exon 20 insertions occur within the loop following the regulatory C-helix and activate the kinase domain of EGFR without generating a therapeutic window to gefitinib, erlotinib, afatinib, dacomitinib or osimertinib. Mobocertinib represents a novel class of covalent EGFR inhibitors with a modest therapeutic window to these mutants and induces anti-tumor responses in a portion of patients [at 160 mg/day: response rate of <30% with duration of response (DoR) >17 months and progression-free survival (PFS) of >7 months] albeit with mucocutaneous and gastrointestinal toxicities. The bi-specific EGFR-MET antibody amivantamab-vmjw has modest but broad preclinical activity in EGFR-driven cancers and specifically for EGFR exon 20 insertion-mutated NSCLC has response rates <40% and PFS of <8.5 months at the cost of both infusion-related plus on-target toxicities. Both drugs were approved in 2021. The clinical development of kinase inhibitors for ERBB2-mutated NSCLC has been thwarted by mucocutaneous/gastrointestinal toxicities that preclude a pathway for drug approval, as the case of poziotinib. However, the activation of ERBB2 has allowed for repurposing of antibody-drug conjugates (ADCs) that target ERBB2 with cytotoxic payloads. The FDA approved fam-trastuzumab deruxtecan-nxki in 2022 for NSCLC based on response rate of >55%, DoR >9 months, PFS >8 months and manageable adverse events (including cytopenias, nausea and less commonly pneumonitis). Other therapies in clinical development include sunvozertinib and zipalertinib, among others. In addition, traditional cytotoxic chemotherapy has some activity in these tumors. Conclusions: The approvals of mobocertinib, amivantamab, and trastuzumab deruxtecan represent the first examples of precision oncology for EGFR exon 20 insertion-mutated and ERBB2-mutated NSCLCs.

EGFR exon 19 insertion EGFR-K745_E746insIPVAIK and others with rare XPVAIK amino-acid insertions: Preclinical and clinical characterization of the favorable therapeutic window to all classes of approved EGFR kinase inhibitors.

BACKGROUND: The epidermal growth factor receptor (EGFR)-K745_E746insIPVAIK and others with XPVAIK amino-acid insertions are exon 19 insertion mutations, which, at the structural modeling level, resemble EGFR tyrosine kinase inhibitor (TKI)-sensitizing mutants. An important unmet need is the characterization of therapeutic windows plus clinical outcomes of exon 19 XPVAIK amino-acid insertion mutations to available EGFR TKIs. METHODS: We used preclinical models of EGFR-K745_E746insIPVAIK and more typical EGFR mutations (exon 19 deletion, L858R, L861Q, G719S, A763_Y764insFQEA, other exon 20 insertion mutations) to probe representative 1st (erlotinib), 2nd (afatinib), 3rd generation (osimertinib), and EGFR exon 20 insertion active (mobocertinib) TKIs. We also compiled outcomes of EGFR exon 19 insertion mutated lung cancers-from our institution plus the literature-treated with EGFR TKIs. RESULTS: Exon 19 insertions represented 0.3-0.8% of all EGFR kinase domain mutation in two cohorts (n = 1772). Cells driven by EGFR-K745_E746insIPVAIK had sensitivity to all classes of approved EGFR TKIs when compared to cells driven by EGFR-WT in proliferation assays and at the protein level. However, the therapeutic window of EGFR-K745_E746insIPVAIK driven cells was most akin to those of cells driven by EGFR-L861Q and EGFR-A763_Y764insFQEA than the more sensitive patterns seen with cells driven by an EGFR exon 19 deletion or EGFR-L858R. The majority (69.2%, n = 26) of patients with lung cancers harboring EGFR-K745_E746insIPVAIK and other mutations with rare XPVAIK amino-acid insertions responded to clinically available EGFR TKIs (including icotinib, gefitinib, erlotinib, afatinib and osimertinib), with heterogeneous periods of progression-free survival. Mechanisms of acquired EGFR TKI resistance of this mutant remained underreported. CONCLUSIONS: This is the largest preclinical/clinical report to highlight that EGFR-K745_E746insIPVAIK and other mutations with exon 19 XPVAIK amino-acid insertions are rare but sensitive to clinically available 1st, 2nd, and 3rd generation as well as EGFR exon 20 active TKIs; in a pattern that mostly resembles the outcomes of models with EGFR-L861Q and EGFR-A763_Y764insFQEA mutations. These data may help with the off-label selection of EGFR TKIs and clinical expectations of outcomes when targeted therapy is deployed for these EGFR mutated lung cancers.

ALK Deletion Exons 2 to 19: Case Report of a Rare ALK Inhibitor-Responsive Lung Cancer Driver Oncogene.

ALK internal deletions of nonkinase domain exons occur in 0.01% of lung cancers with ALK genomic aberrations. We report a lung adenocarcinoma with a previously undescribed somatic ALK deletion of exons 2 to 19 with dramatic and sustained (>23 mo) response to alectinib. Our and other reported cases with ALK nonkinase domain deletions (between introns and exons 1-19) can display positive results in nonsequencing-based lung cancer diagnostic tests (such as immunohistochemistry) used to screen for more common ALK rearrangements. This case report emphasizes that "ALK-driven" lung cancers should be expanded to encompass those harboring not only ALK rearrangements with other genes but also ALK nonkinase domain deletions.

TIP60 is required for tumorigenesis in non-small cell lung cancer.

Histone modifications play crucial roles in transcriptional activation, and aberrant epigenetic changes are associated with oncogenesis. Lysine (K) acetyltransferases 5 (TIP60, also known as KAT5) is reportedly implicated in cancer development and maintenance, although its function in lung cancer remains controversial. Here we demonstrate that TIP60 knockdown in non-small cell lung cancer cell lines decreased tumor cell growth, migration, and invasion. Furthermore, analysis of a mouse lung cancer model with lung-specific conditional Tip60 knockout revealed suppressed tumor formation relative to controls, but no apparent effects on normal lung homeostasis. RNA-seq and ChIP-seq analyses of inducible TIP60 knockdown H1975 cells relative to controls revealed transglutaminase enzyme (TGM5) as downstream of TIP60. Investigation of a connectivity map database identified several candidate compounds that decrease TIP60 mRNA, one that suppressed tumor growth in cell culture and in vivo. In addition, TH1834, a TIP60 acetyltransferase inhibitor, showed comparable antitumor effects in cell culture and in vivo. Taken together, suppression of TIP60 activity shows tumor-specific efficacy against lung cancer, with no overt effect on normal tissues. Our work suggests that targeting TIP60 could be a promising approach to treating lung cancer.

Complete pathologic response to short-course neoadjuvant alectinib in mediastinal node positive (N2) ALK rearranged lung cancer.

OBJECTIVES: Neoadjuvant therapy prior to surgical resection for locally advanced lung cancer has evolved to incorporate systemic cytotoxic chemotherapy +/- immunotherapy +/- radiotherapy. The role of neoadjuvant precision therapies remains understudied. MATERIALS AND METHODS: We report cases with major and complete pathologic responses to off-label neoadjuvant alectinib. RESULTS: A case with stage IIIA (cT1b cN2 cM0) EML4-ALK variant 3a/b lung adenocarcinoma received 6 weeks of alectinib followed by R0 left upper lobectomy with complete pathological response (ypT0 ypN0). Another case with stage IIIA (cT3 cN2 cM0) EML4-ALK variant 2 received 12 weeks of alectinib followed by R0 right middle lobectomy with a major pathologic response (ypT1a ypN0) but systemic recurrence 12 months post-operatively. CONCLUSION: Ongoing clinical trials are evaluating the role of both neoadjuvant and adjuvant ALK-directed therapy. Our cases support the completion of ongoing trials (ALINA: NCT03456076 and ALNEO: NCT05015010), and highlight the ability of second generation ALK inhibitors to induce major and complete pathologic responses in the neoadjuvant setting plus the likely role of long-term adjuvant kinase inhibitor therapy to prevent radiographic/clinical recurrence.

EGFR-D770>GY and Other Rare EGFR Exon 20 Insertion Mutations with a G770 Equivalence Are Sensitive to Dacomitinib or Afatinib and Responsive to EGFR Exon 20 Insertion Mutant-Active Inhibitors in Preclinical Models and Clinical Scenarios.

Epidermal growth factor receptor (EGFR) exon 20 insertion mutations account for a tenth of all EGFR mutations in lung cancers. An important unmet clinical need is the identification of EGFR exon 20 insertion mutants that can respond to multiple classes of approved EGFR-TKIs. We sought to characterize variants involving EGFR-D770 to EGFR-G770 position equivalence changes that structurally allow for response to irreversible 2nd generation EGFR-TKIs. Our group used preclinical models of EGFR exon 20 insertion mutations to probe representative 1st (erlotinib), 2nd (afatinib, dacomitinib), 3rd generation (osimertinib) and EGFR exon 20 insertion mutant-active (poziotinib, mobocertinib) TKIs; we also queried the available clinical literature plus our institutional database to enumerate clinical outcomes. EGFR-D770>GY and other EGFR insertions with a G770 equivalence were identified at a frequency of 3.96% in separate cohorts of EGFR exon 20 insertion mutated lung cancer (n = 429). Cells driven by EGFR-D770>GY were insensitive to erlotinib and osimertinib, displayed sensitivity to poziotinib and dacomitinib and were uniquely sensitive to afatinib and dacomitinib in comparison with other more typical EGFR exon 20 insertion mutations using proliferation and biochemical assays. Clinical cases with EGFR-G770 equivalence from the literature and our center mirrored the preclinical data, with radiographic responses and clinical benefits restricted to afatinib, dacomitinib, poziotinib and mobocertinib, but not to erlotinib or osimertinib. Although they are rare, at <4% of all exon 20 insertion mutations, EGFR-G770 equivalence exon 20 insertion mutations are sensitive to approved 2nd generation EGFR TKIs and EGFR exon 20 insertion mutant-active TKIs (mobocertinib and poziotinib). EGFR-D770>GY and other insertions with a G770 equivalence join EGFR-A763_Y764insFQEA as exon 20 insertion mutationsresponsive to approved EGFR TKIs beyond mobocertinib; this data should be considered for clinical care, genomic profiling reports and clinical trial elaboration.

Randomized Phase II Study of 3 Months or 2 Years of Adjuvant Afatinib in Patients With Surgically Resected Stage I-III EGFR-Mutant Non-Small-Cell Lung Cancer.

For patients with surgically resected disease, multiple studies suggest a benefit of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in delaying cancer recurrence. The necessary duration of therapy for benefit is unknown. MATERIALS AND METHODS: This randomized phase II study enrolled patients with completely resected stage IA-IIIB EGFR-mutant non-small-cell lung cancer (American Joint Committee on Cancer 7th edition) after stage-appropriate standard-of-care adjuvant therapy. Patients were randomly assigned 1:1 to 3 months or 2 years of adjuvant afatinib starting at 30 mg by mouth daily. Computed tomography imaging was performed every 6 months for 3 years and then annually. The primary study end point for this planned 92-patient trial was recurrence rate at 2 years from randomization. A 20% improvement (from 70% with 3 months to 90% with 2 years) was targeted. RESULTS: Forty-six patients enrolled and 45 were treated. The assigned course of afatinib treatment was completed by 96% (22/23) of patients in the 3-month group and only 41% (9/22) in the 2-year group. The 2-year recurrence-free survival (RFS) rates were 70% in the 3-month group and 81% in the 2-year group (P = .55). The median RFS was 42.8 months in the 3-month group and 58.6 months in the 2-year group. Side effects were consistent with those previously described for afatinib. CONCLUSION: Recurrences at 2 years were 11% less common with 2 years versus 3 months of adjuvant afatinib. This difference did not meet the 20% primary study target, likely because of underaccrual and early drug discontinuation on the 2-year group. With the availability of osimertinib with better efficacy and tolerability than earlier-generation agents, the optimal duration of adjuvant EGFR TKI therapy remains an important question.

Preclinical characterization of mobocertinib highlights the putative therapeutic window of this novel EGFR inhibitor to EGFR exon 20 insertion mutations.

BACKGROUND: Epidermal growth factor receptor (EGFR) exon 20 insertion mutations account for 10% of all EGFR mutations and are mostly insensitive to approved EGFR-tyrosine kinase inhibitors (EGFR-TKIs). Novel EGFR-TKIs have been developed or repurposed for these mutants. A limited number of preclinical studies have detailed these EGFR-TKIs. We sought to use commercially available mobocertinib (TAK-788) to characterize the preclinical therapeutic window of this EGFR-TKI against EGFR mutations and to probe possible on-target mechanisms of resistance (EGFR-C797S). METHODS: We used models of EGFR mutations to probe representative 1st, 2nd, 3rd generation, and in-development EGFR exon 20-active (poziotinib, mobocertinib) TKIs. We also introduced EGFR-C797S to these models to identify mechanisms of resistance. RESULTS: Cells driven by the most common EGFR exon 20 insertion mutations (A767_V769dupASV, D770_N771 insSVD, H773_V774insH and others) were inhibited by in-development EGFR TKIs at doses below those affecting EGFR-wildtype; albeit more common EGFR mutations (exon 19 deletions and L858R) were inhibited more readily by mobocertinib and poziotinib. Mobocertinib was able to inhibit phosphorylation of EGFR in multiple preclinical models. The presence of EGFR-C797S led to >200-fold resistance in proliferation assays probing mobocertinib and osimertinib. Review of clinical studies of mobocertinib disclosed responses that could be lasting. CONCLUSIONS: This is one of the initial reports to characterize the novel EGFR TKI mobocertinib and highlights its broad activity against EGFR mutants plus the therapeutic window to EGFR exon 20 insertion mutations; as well as EGFR-C797S as a possible mechanism of resistance. Further clinical development of mobocertinib merits continuation.

Activity and Safety of Mobocertinib (TAK-788) in Previously Treated Non-Small Cell Lung Cancer with EGFR Exon 20 Insertion Mutations from a Phase I/II Trial.

Mobocertinib, an oral epidermal growth factor receptor (EGFR) inhibitor targeting EGFR gene mutations, including exon 20 insertions (EGFRex20ins), in non-small cell lung cancer, was evaluated in a phase I/II dose-escalation/expansion trial (ClinicalTrials.gov NCT02716116). Dose escalation identified 160 mg/d as the recommended phase 2 dose and maximum tolerated dose. Among 136 patients treated with 160 mg/d, the most common any-grade treatment-related adverse events (TRAE; >25%) were diarrhea (83%), nausea (43%), rash (33%), and vomiting (26%), with diarrhea (21%) the only grade ≥3 TRAE >5%. Among 28 EGFRex20ins patients treated at 160 mg/d, the investigator-assessed confirmed response rate was 43% (12/28; 95% confidence interval, 24%-63%) with median duration of response of 14 months (5.0-not reached) and median progression-free survival of 7.3 months (4.4-15.6). Mobocertinib demonstrated antitumor activity in patients with diverse EGFRex20ins variants with a safety profile consistent with other EGFR inhibitors. SIGNIFICANCE: No oral EGFR-targeted therapies are currently approved for patients with EGFRex20ins NSCLC. Mobocertinib demonstrated antitumor activity with manageable toxicity in patients with advanced EGFRex20ins NSCLC in this study, supporting additional development of mobocertinib in this patient population.See related commentary by Pacheco, p. 1617.This article is highlighted in the In This Issue feature, p. 1601.

Time to SARS-CoV-2 clearance among patients with cancer and COVID-19.

BACKGROUND: For cancer patients, coronavirus disease 19 (COVID-19) infection can lead to delays in cancer therapy both due to the infection itself and due to the need to minimize exposure to other patients and to staff. Clearance guidelines have been proposed, but expected time to clearance has not been established. METHODS: We identified all patients at a tertiary care hospital cancer center between 25 March 2020 and 6 June 2020 with a positive nasopharyngeal reverse transcriptase polymerase chain reaction (RT-PCR) test for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a cancer-related visit within 3 years, and at least one follow-up assay. We determined the time to clearance using American Society of Clinical Oncology (ASCO), the UK National Institute for Health and Care Excellence (UK-NICE), and Centers for Disease Control and Prevention (CDC) criteria. A matched non-cancer comparison cohort was also identified. RESULTS: Thirty-two cancer patients were identified. Nineteen were cleared by ASCO criteria, with estimated median time to clearance of 50 days. Fourteen patients resumed chemotherapy prior to clearance. Using UK-NICE criteria, median time to clearance would have been 31 days, and using CDC criteria, it would have been 13 days. The matched non-cancer cohort had similar clearance time, but with less frequent testing. CONCLUSION: SARS-CoV-2 clearance times differ substantially depending on the criteria used and may be prolonged in cancer patients. This could lead to a delay in cancer care, increased use of clearance testing, and extension of infection control precautions.

Association of Performance Status With Survival in Patients With Advanced Non-Small Cell Lung Cancer Treated With Pembrolizumab Monotherapy.

Importance: Despite approximately 40% of patients having Eastern Cooperative Oncology Group (ECOG) performance status (PS) scores of at least 2 in the real world, most landmark clinical trials that led to the use of pembrolizumab as standard of care in advanced non-small cell lung cancer (NSCLC) excluded this group. Objective: To evaluate whether an ECOG PS score of at least 2 at the start of therapy is associated with progression-free survival (PFS) and overall survival (OS) in advanced NSCLC treated with pembrolizumab monotherapy. Design, Setting, and Participants: This cohort study included all consecutive patients with advanced NSCLC who underwent treatment with palliative pembrolizumab monotherapy from February 2016 to October 2019 at a single academic cancer center, with data censoring on January 15, 2020. Exposures: ECOG PS score at start of therapy, with 0 and 1 indicating fully active or restricted in strenuous activity and scores of 2 and higher indicating increasing disability. Main Outcomes and Measures: PFS and OS, measured from initiation of pembrolizumab monotherapy. Results: Of 74 patients (median [range] age, 68.5 [33-87] years; 36 [48.7%] women; 53 [71.6%] White individuals) with median follow-up of 19.5 (95% CI, 13.4-27.8) months, 45 (60.8%) had an ECOG PS of 0 or 1, while 29 (39.2%) had an ECOG PS of at least 2. There were no significant differences in the baseline characteristics, except in age. Compared with patients with PS scores of 0 or 1, those with PS scores of at least 2 had significantly lower disease control rates (38 [88.4%] vs 15 [53.6%]; P = .002), shorter median PFS (7.9 [95% CI, 4.6-15.4] months vs 2.3 [95% CI, 1.8-4.8] months; P = .004), and shorter median OS (23.2 [14.0 vs 35.7] months vs 4.1 [95% CI, 2.1-6.9] months; P < .001). Among those potentially eligible for subsequent cancer-directed therapy beyond pembrolizumab monotherapy, patients in the group with PS scores of at least 2 were less likely to receive it than those with PS scores of 0 or 1 (2 [8.3%] vs 14 [45.2%]; P = .003). Multivariable adjustment for baseline characteristics confirmed ECOG PS of at least 2 as an independent risk factor for worse PFS (HR, 2.02; 95% CI, 1.09-3.74; P = .03) and worse OS (HR, 2.87; 95% CI, 1.40-5.89; P = .004). Conclusions and Relevance: In this cohort study, having an ECOG PS score of at least 2 was associated with poorer prognosis for treatment of advanced NSCLC with palliative pembrolizumab monotherapy. Further prospective studies are needed to evaluate more objective and consistent measures of functional status to facilitate identification of patients with borderline performance status who may achieve durable clinical benefit from treatment with pembrolizumab monotherapy.

Clinical Benefit of Tyrosine Kinase Inhibitors in Advanced Lung Cancer with EGFR-G719A and Other Uncommon EGFR Mutations.

The optimal management of advanced non-small cell lung cancer (NSCLC) with noncanonical epidermal growth factor receptor (EGFR) mutations (i.e., exon 19 deletion and exon 21 L858R) is constrained by the heterogeneous behavior of individual uncommon mutations and limited prospective clinical data in this setting. Despite encouraging results with osimertinib from a recently published phase II trial from South Korea, afatinib remains the only currently approved drug for patients with tumors harboring uncommon EGFR mutations (i.e., S768I, L861Q, and/or G719X). When used at the standard dose of 40 mg daily, afatinib is associated with significant rates of treatment-related adverse events, leading to frequent dose reductions and treatment discontinuations. We report a case of a woman with advanced NSCLC harboring EGFR-G719A mutation treated with afatinib (at an off-label pulse dose strategy that merits further evaluation in prospective studies) with sustained partial response for 20 months with manageable expected toxicities. Subsequent disease progression was mediated by off-target pan-EGFR inhibitor (including osimertinib)-resistant KRAS mutation and not by acquisition of EGFR-T790M. We further present the current state of evidence in the literature behind use of first-, second-, and third-generation tyrosine kinase inhibitors and summarize the evolving spectrum of activity ascribed to osimertinib (and newer EGFR inhibitors with a more favorable therapeutic window and intracranial penetration) in this population of patients with advanced NSCLC and uncommon EGFR mutations. KEY POINTS: Uncommon EGFR mutations characterize a heterogeneous group of patients with advanced non-small cell lung cancer (NSCLC). Afatinib is the only currently U.S. Food and Drug Administration-approved drug for management of advanced NSCLC with uncommon EGFR mutations (S768I, L861Q, and/or G719X). Afatinib treatment at 40 mg daily is associated with high rates of adverse events and dose reductions; alternative strategies including pulse intermittent dosing should be evaluated prospectively. Osimertinib (with favorable safety profile and intracranial penetration) has shown promising results in this population in a phase II trial from South Korea; additional trials are ongoing.