BACKGROUND: This retrospective study aimed to investigate treatment patterns and outcomes in patients with NSCLC harboring EGFR20ins in China. EGFR20ins mutations are associated with poor responses to EGFR-TKIs, and limited real-world data exist regarding the efficacy of various treatment modalities.
METHODS: In this retrospective, single-center study, treatment outcomes, including PFS and ORR, were evaluated for different treatment regimens based on imaging assessments. The impact of mutation heterogeneity on treatment efficacy was also explored.
RESULTS: Data from 302 patients diagnosed with NSCLC with EGFR20ins were analyzed. EGFR-TKI monotherapy demonstrated suboptimal PFS compared to platinum-based chemotherapy in the first-line setting (3.00 m vs. 6.83 m, HR = 3.674, 95%CI = 2.48-5.44, p < 0.001). Platinum plus pemetrexed plus bevacizumab combination therapy showed improved PFS and ORR compared to platinum plus pemetrexed (7.50m vs. 5.43 m, HR = 0.593, 95%CI = 0.383-0.918, p = 0.019). In later-line treatments, monotherapy with EGFR-TKIs or ICIs exhibited suboptimal efficacy. The specific EGFR20ins subtype, A763_Y764insFQEA, showed favorable responses to EGFR-TKIs in real-world settings.
CONCLUSIONS: This large-scale real-world study provides valuable insights into the treatment patterns and outcomes of NSCLC patients with EGFR20ins mutations in China. These findings contribute to the understanding of EGFR20ins treatment and provide real-world benchmark for future clinical trials and drug development.

BACKGROUND: Although amivantamab has shown clinical benefits for non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) exon 20 insertions, its cost-effectiveness requires further investigation.
OBJECTIVE: To evaluate the cost-effectiveness of amivantamab plus chemotherapy for the treatment of NSCLC patients with EGFR exon 20 insertions from the United States payer perspective.
METHODS: A partitioned survival model was developed based on the data from the PAPILLON trial. Costs were derived from the pricing files of Medicare and Medicaid Services and published literature, and utility values were derived from previous studies. A 3% annual discount rate was applied to both costs and outcomes. The primary outcome was the incremental cost-effectiveness ratio (ICER). One-way sensitivity analysis, probabilistic sensitivity analysis and scenario analysis, were conducted to test the model stability.
RESULTS: Amivantamab plus chemotherapy yielded an additional 1.12 quality-adjusted life years (QALYs) while increasing costs by $483,769.50 relative to the chemotherapy regimen, leading to an ICER of $432,401.16/QALY. The combination of amivantamab with chemotherapy was not cost effective at a threshold of $150,000/QALY. In the scenario analysis, the results showed that the ICERs were $263,680.69/QALY and $418,416.35/QALY when different utility values and 10-year time horizons were adopted, respectively. For PSA, the probability that amivantamab plus chemotherapy would be cost-effective was 0% if the willingness-to-pay (WTP) threshold was $150,000/QALY.
CONCLUSIONS: Amivantamab plus chemotherapy is unlikely to be a cost-effective option for NSCLC patients with EGFR exon 20 insertions. Reducing the cost of amivantamab may produce favorable economic outcomes.

BACKGROUND: Mobocertinib, an EGFR exon 20 insertion (Ex20ins)-specific tyrosine kinase inhibitor has been used for treatment of advanced/metastatic EGFR Ex20ins-mutant non-small cell lung cancer (NSCLC). However, resistance mechanisms to EGFR Ex20ins-specific inhibitors and the efficacy of subsequent amivantamab treatment is unknown.
METHODS: To investigate resistance mechanisms, tissue and cfDNA samples were collected before treatment initiation and upon development of resistance from NSCLC patients with EGFR Ex20ins mutations received mobocertinib, poziotinib, and amivantamab treatments. Genetic alterations were analyzed using whole-genome and targeted sequencing, and in vitro resistant cell lines were generated for validation.
RESULTS: EGFR amplification (n = 6, including 2 broad copy number gain) and EGFR secondary mutation (n = 3) were observed at the resistance of mobocertinib. One patient had both EGFR secondary mutation and high EGFR focal amplification. In vitro models harboring EGFR alterations were constructed to validate resistance mechanisms and identify overcoming strategies to resistance. Acquired EGFR-dependent alterations were found to mediate resistance to mobocertinib in patients and in vitro models. Furthermore, two of six patients who received sequential amivantamab followed by an EGFR tyrosine kinase inhibitor had MET amplification and showed partial response.
CONCLUSIONS: Our study revealed EGFR-dependent and -independent mechanisms of mobocertinib resistance in patients with advanced EGFR Ex20ins-mutant NSCLC.

UNASSIGNED: In the single-arm CHRYSALIS trial, advanced non-small cell lung cancer patients harboring epidermal growth factor receptor (EGFR) exon 20 insertion (Exon 20ins) showed durable responses to amivantamab, an EGFR-MET bispecific antibody targeting tumors with EGFR Exon 20ins. This study compared the effectiveness of amivantamab to real-world systemic anti-cancer therapies in Japan.
UNASSIGNED: External control patients were selected by applying CHRYSALIS eligibility to Japanese patients from LC-SCRUM-Asia. External control patients were included for every qualifying line of therapy after platinum-based chemotherapy. Propensity score weighting was applied to external control patients to adjust for differences in baseline characteristics. Outcomes were compared between external control patients, and all and Asian-only CHRYSALIS patients using weighted Cox proportional hazards regression models for progression-free survival (PFS), time to next therapy (TTNT), and overall survival (OS), and generalized estimating equations with repeated measurements for overall response rate (ORR).
UNASSIGNED: One hundred fifteen CHRYSALIS and 94 external control patients were identified. Compared to external control patients, amivantamab-treated patients had significantly longer OS (median OS 19.88 vs 14.09 months, HR [95% CI] 0.59 [0.40-0.88]), PFS (median PFS 6.74 vs 4.73 months, HR 0.59 [0.45-0.78]), TTNT (median TTNT 12.16 vs 5.09 months, HR 0.39 [0.29-0.53]), and significantly higher ORR (41.7% vs 14.1%). Analyses of amivantamab-treated Asian patients (n = 61) showed similar clinical benefits.
UNASSIGNED: In the absence of clinical evidence from randomized clinical trials, this study reflects the benefit of amivantamab after platinum-based chemotherapy for advanced non-small cell lung cancer patients harboring EGFR Exon 20ins, compared to current real-world therapies.

The third most prevalent type of epidermal growth factor receptor (EGFR) mutation, EGFR exon 20 insertions (EGFRex20ins), involves 2%-12% of all cases of EGFR-positive non-small cell lung cancer (NSCLC). Approximately 90% of the mutations occur within the loop structure region, and the most frequently reported subtypes are A767_V769dup and S768_D770dup, which together account for almost 50% of instances. Apart from the unique subtype of A763_Y764insFQEA, NSCLCs with EGFRex20ins are resistant to approved EGFR tyrosine kinase inhibitors (TKIs) and are also insensitive to chemotherapy or immunotherapy. A new modality of treatment for NSCLC patients with EGFRx20ins has been established with the approval of mobocertinib and amivantamab. There are also numerous novel targeted treatments for NSCLC with EGFRex20ins in development, which are anticipated to improve this patient population\'s survival even further. This review provides a reference for the clinical management of these patients by summarizing the most recent epidemiological, and clinicopathological characteristics, diagnostic techniques, and therapeutic advances of EGFRex20ins in NSCLC.

UNASSIGNED: This study describes treatment patterns and outcomes in patients with NSCLC with EGFR exon 20 insertions (EGFRex20ins) in the United States.
UNASSIGNED: The Flatiron Health electronic health record database was used to select three cohorts among patients diagnosed with NSCLC with EGFRex20ins (January 1, 2011-February 29, 2020): (1) first-line (1L) or patients receiving 1L therapy after documented EGFRex20ins; (2) second or later-line (≥2L) or patients receiving ≥2L therapy after documented EGFRex20ins; and (3) ≥2L postplatinum trial-aligned, or ≥2L patients previously treated with platinum chemotherapy whose baseline characteristics aligned with key eligibility criteria (initiating new treatment after documented EGFRex20ins and ≥1 previous treatment excluding mobocertinib or amivantamab) of the mobocertinib trial NCT02716116. Real-world end points were confirmed overall response rate, overall survival, and progression-free survival.
UNASSIGNED: Of 237 patients with EGFRex20ins-mutated NSCLC, 129 and 114 patients were included in the 1L and ≥2L cohorts, respectively. In 1L patients, platinum chemotherapy plus nonplatinum chemotherapy (31.0%) and EGFR tyrosine kinase inhibitors (28.7%) were the most common regimens. In ≥2L patients, immuno-oncology monotherapy (28.1%) and EGFR tyrosine kinase inhibitors (17.5%) were the most common index treatments. For any 1L, ≥2L, and ≥2L postplatinum trial-aligned patients, the confirmed overall response rate was 18.6%, 9.6%, and 14.0%, respectively; the median overall survival was 17.0, 13.6, and 11.5 months; the median progression-free survival was 5.2, 3.7, and 3.3 months, respectively.
UNASSIGNED: The outcomes for patients with NSCLC with EGFRex20ins were poor. This real-world study provides a benchmark on treatment outcomes in this patient population and highlights the unmet need for improved therapeutic options.

Insertions in exon 20 represent the third most common type of EGFR mutation following in-frame deletions in exon 19 and the point mutation L858R in exon 21. They are generally associated with primary resistance to EGFR-TKIs. Although mobocertinib and amivantamab were approved for adult patients with non-small cell lung cancer (NSCLC) harboring EGFR exon 20 insertion mutations, the efficacy of these two agents was rather moderate. Therefore, other more potent targeted agents are urgently needed. Here, we report a patient with advanced lung adenocarcinoma harboring an EGFR exon 20 insertion mutation (NM_005228: exon 20: c.2316_2321dup: p.773_774dup). After experiencing platinum-based chemotherapy, this patient received a combination of furmonertinib and anlotinib and achieved lasting stable disease (SD). The treatment was well tolerated, and only mild hand-foot syndrome was reported from the patient. To the best of our knowledge, this case firstly reported the encouraging efficacy of combined furmonertinib and anlotinib in an advanced lung adenocarcinoma patient with an EGFR exon 20 insertion mutation who was previously treated with platinum-based chemotherapy. In addition, we summarize the recent literature on therapies against NSCLC with EGFR exon 20 insertion mutations. This case might provide an alternative approach for clinical oncologists.

UNASSIGNED: Previously, we developed a database of 693 patients with NSCLC and uncommon EGFR mutations treated with afatinib. Here, we provide an update of >1000 patients, with more data on specific mutations.
UNASSIGNED: Patients were identified from a prospective database developed by Boehringer Ingelheim and via literature review. Mutations were categorized as T790M-positive, exon 20 insertions, major uncommon (G719X, L861Q, S768I) and \'others\'. Patients with compound mutations (≥2 EGFR mutations) were analyzed separately. Key endpoints were time to treatment failure (TTF) and objective response rate (ORR).
UNASSIGNED: Of 1023 patients included, 587 patients were EGFR TKI-naïve and 425 were EGFR TKI-pretreated. The distribution of mutation categories was: major uncommon (41.4%); exon 20 insertions (22.3%); T790M (20.3%); and \'others\' (15.9%); 38.6% had compound mutations. Overall, median TTF (TKI naïve/pretreated) was 10.7 and 4.5 months. ORR was 49.8% and 26.8%, respectively. In TKI-naïve patients, afatinib demonstrated activity against major uncommon mutations (median TTF: 12.6 months; ORR: 59.0%), \'other\' mutations (median TTF: 10.7 months; ORR: 63.9%) including strong activity against E709X (11.4 months; 84.6%) and L747X (14.7 months; 80.0%), and compound mutations (11.5 months; 63.9%). Although sample sizes were small, notable activity was observed against specific exon 20 insertions at residues A763, M766, N771, and V769, and against osimertinib resistance mutations (G724S, L718X, C797S).
UNASSIGNED: Afatinib should be considered as a first-line treatment option for NSCLC patients with major uncommon, compound, \'other\' (including E709X and L747X) and some specific exon 20 insertion mutations. Moderate activity was seen against osimertinib resistance EGFR mutations.

BACKGROUND: EGFR exon 20 insertions (EGFRex20ins) are a diverse set of mutations in NSCLC that are refractory to tyrosine kinase inhibitors. We describe real-world EGFRex20ins detection patterns in patients with advanced NSCLC in the United States.
METHODS: Data from 2011 to 2020 were extracted from the Flatiron Health electronic health record-derived deidentified database.
RESULTS: Among 67,281 patients with advanced NSCLC and at least two clinic visits, 66.8% were tested for EGFR mutations, of whom 13.9% tested positive. Of these, 4.9% had EGFRex20ins. The median time from NSCLC diagnosis to the first positive EGFRex20ins test result was 23 days, including 9 days of laboratory testing time. The EGFRex20ins were reported in 0.6% to 1.0% of all patients with advanced NSCLC and account for 3.9% to 5.3% of all EGFR mutations. During the study period, reverse transcription-polymerase chain reaction testing rates decreased whereas next-generation sequencing rates increased both in overall and among patients with tumors positive for EGFRex20ins. Tissue was the most common sample type used for EGFR and EGFRexon20ins detection (81.1% and 84.9%, respectively), whereas blood sampling for EGFRexon20ins detection increased from 0% (2011) to 37.2% (2020). For 23.7% of patients with EGFRex20ins, treatment was initiated before receiving the first positive EGFRex20ins test result, with therapies including immuno-oncology agents as the most common treatment type from 2017 to 2020.
CONCLUSIONS: EGFR testing and detection of EGFRex20ins in patients with NSCLC have increased slightly over time with the increasing use of next-generation sequencing. The current late-stage development of EGFRex20ins-targeted therapy is driving a need for more efficient testing.

BACKGROUND: Real-world clinical outcomes in patients with advanced NSCLC harboring EGFR exon 20 insertion (exon20ins) mutations have not been extensively studied. We conducted a retrospective cohort study to assess the clinical outcomes of EGFR exon20ins compared with common EGFR (cEGFR) mutations.
METHODS: Adults with advanced NSCLC harboring any EGFR mutations in the NSCLC Flatiron registry (2011 through May 2020) were included. To compare the relative prognosis (prognostic value) of exon20ins vs cEGFR, real-world overall survival (rwOS) was the primary endpoint. Separately, to compare the relative response to tyrosine kinase inhibitor (TKI) treatment (predictive value), real-world progression-free survival (rwPFS) was the primary endpoint.
RESULTS: For the prognostic value analysis, 3014 patients with EGFR mutant NSCLC (cEGFR, n = 2833; EGFR exon20ins, n = 181) were eligible. The median (95% CI) rwOS was 16.2 (11.04-19.38) months in the EGFR exon20ins cohort vs 25.5 (24.48-27.04) months in the cEGFR cohort (adjusted HR, 1.75 [1.45-2.13]; p < 0.0001); 5-year rwOS was 8% and 19%, respectively. For the predictive value analysis, 2825 patients received TKI treatment and were eligible (cEGFR, n = 2749; EGFR exon20ins, n = 76). The median (95% CI) rwPFS from start of the first TKI was 2.9 (2.14-3.91) months in the EGFR exon20ins cohort vs 10.5 (10.05-10.94) months in the cEGFR cohort (adjusted HR, 2.69 [2.05-3.54]; p < 0001). Among patients with EGFR exon20ins, the most common prescribed first-line therapy was platinum-based chemotherapy (61.3%) followed by EGFR TKIs (21.5%); second-line treatments were varied, with no clear standard of care.
CONCLUSIONS: Patients with EGFR exon20ins have poor prognosis and receive little benefit from EGFR TKI treatment. More effective therapies are needed in this difficult-to-treat population.