Molecular correlation of response to pyrotinib in advanced NSCLC with HER2 mutation: biomarker analysis from two phase II trials

BACKGROUND

Non-small cell lung cancer (NSCLC) with HER2 mutation has entered into the era of targeted therapy. However, both anti-HER2 antibody-drug conjugates (ADCs) and tyrosine kinase inhibitors (TKIs) showed moderate objective response rate (ORR) and median progression-free survival (PFS). The aim of this study was to investigate the molecular features of responders to pyrotinib in advanced NSCLC with HER2 mutation.

METHODS

Patients from our two previous phase II trials were pooled analyzed. Their circulating tumor DNA (ctDNA) were detected by next-generation sequencing (NGS) panels, and the correlation with the efficacy of pyrotinib was investigated.

RESULTS

This pooled analysis included 75 patients, and 50 of them with baseline plasma samples were finally enrolled with a median age of 57 years old. The overall ORR and median PFS were 28% and 7.0 months respectively. Biomarker analysis showed that 5 patients were ctDNA nonshedding. Patients with TP53 wild type were significantly associated with higher disease control rate (97.1%vs. 68.8%, p = 0.010), PFS (median 8.4 vs. 2.8 months, p = 0.001) and overall survival (OS, median 26.7 vs. 10.4 months, p < 0.001) than those with mutations. ctDNA of nonshedding and clearance exhibited significantly longer PFS (median: 10.2 vs. 9.8 vs. 5.6 months, p = 0.036) and a trend of longer OS (median: 35.3 vs. 18.1 vs. 14.6 months, p = 0.357) than those not.

CONCLUSION

Patients with TP53 wild type, ctDNA nonshedding, or clearance showed superior efficacy of pyrotinib in patients with HER2-mutated advanced NSCLC, which might be helpful to guide the utility of pyrotinib in clinical setting.

TRIAL REGISTRATION

The patients were from two registered clinical trials (ClinicalTrials.gov: NCT02535507, NCT02834936).

Structure-Activity Relationship Studies Based on Quinazoline Derivatives as EGFR Kinase Inhibitors (2017-Present)

The epidermal growth factor receptor (EGFR) plays a critical role in the tumorigenesis of various forms of cancer. Targeting the mutant forms of EGFR has been identified as an attractive therapeutic approach and led to the approval of three generations of inhibitors. The quinazoline core has emerged as a favorable scaffold for the development of novel EGFR inhibitors due to increased affinity for the active site of EGFR kinase. Currently, there are five first-generation (gefitinib, erlotinib, lapatinib, vandetanib, and icotinib) and two second-generation (afatinib and dacomitinib) quinazoline-based EGFR inhibitors approved for the treatment of various types of cancers. The aim of this review is to outline the structural modulations favorable for the inhibitory activity toward both common mutant (del19 and L858R) and resistance-conferring mutant (T790M and C797S) EGFR forms, and provide an overview of the newly synthesized quinazoline derivatives as potentially competitive, covalent or allosteric inhibitors of EGFR.

Real-world efficacy and safety of mobocertinib in EGFR exon 20 insertion-mutated lung cancer

Background

Non-small cell lung cancer (NSCLC) harboring EGFR exon 20 insertions (EGFRex20ins) is relatively resistant to the existing EGFR tyrosine kinase inhibitors (TKIs). Mobocertinib is a novel TKI that selectively targets EGFRex20ins and has demonstrated therapeutic efficacy in pretreated patients with tumors harboring these mutations.

Methods

This is a retrospective, non-interventional, multicenter real-world study aimed at assessing the efficacy and safety of mobocertinib in patients with EGFRexon20ins who received 160 mg QD monotherapy as part of expanded access. Data collection was based on patients’ records. PET-CT or CT scans were used to measure systemic response, while brain MRIs were used to examine intracranial response as part of the follow-up.

Results

16 patients were included in this report. Mobocertinib was administered to 31.3% (5) of patients as first-line, 50% (8) as second-line, and 18.7% (3) as a later-line therapy. The median age was 65 years (range, 38-83), 75% (12/16) were female, and 50% (8/16) had brain metastases at baseline before mobocertinib treatment. The objective response rate (ORR) to mobocertinib was 25% (4/16) (1/5 for first line and 3/11 for other lines), disease control rate (DCR) was 75% (12/16) with a follow-up period of 11 months. The median duration of treatment (mDoT) was 5.6 months across all patients, and 8.6 months in responders. Based on the presence or absence of brain metastasis, the mDoT was 14.8 and 5.4 months (p=0.01), respectively. Mobocertinib Grade ≥3 treatment-related adverse events (TRAEs) included diarrhea (19%), nausea (6%) and renal failure (6%). Dose reduction was reported in 25% of cases to 80 mg.

Conclusion

Mobocertinib in compassionate use exhibited an ORR of 25%, which is very similar to that of the phase 2 EXCLAIM study and clearly better than historical data of monochemotherapy or conventional EGFR inhibitors. The greatest benefit was noted in patients without brain metastases, who showed durable effects with mDoT 14.8 months, while intracranial activity was limited. These findings may assist therapeutic considerations, inasmuch as results from the EXCLAIM cohort-3 dedicated to brain lesions are not available yet.

Non-small cell lung cancer with EGFR exon 20 insertion mutation: a systematic literature review and meta-analysis of patient outcomes

INTRODUCTION

EGFR exon 20 insertion mutation-positive non-small cell lung cancer (NSCLC) is rare, has a poor prognosis, and outcomes are not fully established. We describe and evaluate outcomes from real-world and clinical evidence in these patients.

METHODS

A systematic literature review (SLR) identified interventional and real-world evidence (RWE) studies reporting clinical outcomes for EGFR exon 20 insertion mutation-positive NSCLC. Meta-analyses were conducted by line of therapy to synthesize pooled survival and response outcomes across RWE. Published evidence from interventional studies was summarized individually.

RESULTS

The SLR identified 23 RWE and 19 original interventional studies. In the meta-analysis of RWE, pooled response and survival outcomes were low for first-line EGFR-tyrosine kinase inhibitors (TKIs) and immuno-oncology (IO) agents. First-line chemotherapy resulted in a pooled ORR 25.7%, pooled PFS 5.6 months, and pooled OS 18.3 months. Pooled outcomes were further reduced in second or later lines (≥2 L): pooled ORR was 5.0%, 3.3%, and 13.9%; pooled PFS was 2.1 months, 2.3 months, and 4.4 months; and pooled OS was 14.1 months, 8.8 months, and 17.1 months (not a pooled result) for EGFR-TKIs, IO agents, and chemotherapy, respectively. Interventional studies reported outcomes for TKIs (mobocertinib, poziotinib, osimertinib, afatinib, CLN-081, DZD9008), a monoclonal antibody (amivantamab), and a heat shock protein 90 inhibitor (luminespib). While there is limited RWE for the recently approved agents mobocertinib and amivantamab, which specifically target exon 20 insertion mutations, interventional evidence supports their potential as effective treatment options.

CONCLUSIONS

Conventional treatments used in patients with EGFR exon 20 insertion mutation-positive NSCLC have limited efficacy, though chemotherapy appeared to be associated with better response and survival outcomes than non-exon 20 targeting EGFR-TKIs and IO agents. This supports the need to identify EGFR exon 20 insertion mutations as the availability of new targeted treatments may offer additional therapeutic options to these patients.

High dose osimertinib in patients with advanced stage EGFR exon 20 mutation-positive NSCLC: Results from the phase 2 multicenter POSITION20 trial

INTRODUCTION

Patients with life-threatening advanced non-small cell lung cancer (NSCLC) who harbor an exon 20 deletion and/or insertion mutation (EGFRex20 + ) have limited effective treatment options. The high dose 3rd generation tyrosine kinase inhibitor (TKI) osimertinib shows promising in vitro activity in EGFRex20 + NSCLC tumors.

METHODS

The POSITION20 is a single arm phase II, multicenter study investigating 160 mg osimertinib in patients with EGFRex20+, T790M negative NSCLC. We allowed patients to be treatment naïve and to have asymptomatic brain metastases. The primary endpoint was overall response rate (ORR). Secondary outcomes were duration of response (DoR), progression free survival (PFS), overall survival (OS), and treatment related adverse events (trAEs).

RESULTS

From June 2018 to October 2021, 25 patients were enrolled across five centers in the Netherlands. The median age was 70 years (range, 47-87), 20 patients (80%) were women, and the median number of previous lines of therapy was 1 (range, 0-3). The exon 20 mutations were clustered between A763 and L777. The most common exon 20 mutations were p.(N771_H773dup) (n = 3) and p.(A767_V769dup) (n = 3). The ORR was 28% (95% CI, 12-49%), including seven partial responses, with a median DoR of 5.3 months (range, 2.7-27.6). The median PFS was 6.8 months (95% CI, 4.6-9.1) and the median OS was 15.2 months (95% CI, 14.3-16.0). The most common trAEs were diarrhea (72%), dry skin (44%), and fatigue (44%). The primary reason for discontinuation was progressive disease in 14 patients (56%).

CONCLUSION

The POSITION20 study showed modest antitumor activity in patients with EGFRex20 + NSCLC treated with 160 mg osimertinib, with a confirmed ORR of 28% and acceptable toxicity.

Epidermal growth factor receptor-targeted therapy for the treatment of non-small cell lung cancer: A review of phase II and III trials

INTRODUCTION

EGFR is one of the most common driver gene mutations in lung cancer. EGFR-TKI monotherapy and EGFR-TKI combined with chemotherapy or anti-angiogenesis drugs have significantly prolonged the survival of patients with EGFR-mutant NSCLC. However, disease progression caused by acquired resistance to EGFR-TKIs is inevitable. And patients with EGFR exon 20ins showed limited efficacy to EGFR-TKIs.

AREAS COVERED

In this review, we initially evaluated the efficacy of existing treatments for EGFR-mutant NSCLC. Second, we reviewed the ongoing phase II and III clinical trials, provide the latest results, discuss the scientific rationale of these trials and the potential development issues.

EXPERT OPINION

The application of EGFR-TKIs has greatly changed the therapeutic strategies for advanced and resected NSCLC with EGFR mutations, and the 5-year OS rate for advanced NSCLC was close to 40%. The current research direction for the treatment of patients with EGFR mutations focuses on the following three aspects: uncommon EGFR mutation subtypes NSCLC, brain metastases, and EGFR TKI-based combination therapy. Future studies on EGFR-mutant NSCLC therapy will focus on overcoming EGFR-TKI-related resistance, preventing drug resistance in advance, and developing bispecific antibody drugs. ADCs may be the promising strategy for patients with acquired resistance to EGFR-TKIs.

Novel targeted therapies for advanced non-small lung cancer

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer accounting for almost 80%-85% of all lung cancer cases. Unfortunately, more than half of the patients will be diagnosed with advanced disease at the time of presentation, which makes their disease incurable. Historically, the 5 year overall survival for advanced NSCLC was 5%. However, there has been a significant increase in our understanding of the genetic basis of NSCLC, which has led to development of both immunotherapy and targeted therapy agents. This has improved the 5 year overall survival to become within the range of 15%-50% depending on certain mutations and biomarkers. Over the last decade the United States Food and Drug Administration (FDA) has approved almost 20 new targeted therapies and clinical trials are still undergoing to evaluate more novel agents. In this review, we will present recent updates on novel targeted therapies.

Cardiovascular Risks with Epidermal Growth Factor Receptor (EGFR) Tyrosine Kinase Inhibitors and Monoclonal Antibody Therapy

PURPOSE OF REVIEW

Tyrosine kinase inhibitors (TKI) and monoclonal antibodies (mAbs) that target the epidermal growth factor receptor (EGFR) have changed the therapeutic landscape across a range of solid malignancies. However, there is little data regarding the cardiovascular (CV) impact of these agents. The purpose of this review is to discuss reported CV effects, pathophysiology, pre-treatment screening, diagnostic workup, and treatment recommendations in this patient population.

RECENT FINDINGS

It is apparent that CV events are not class dependent, and while infrequently reported in clinical trials, unique CV toxicity may occur with EGFR inhibitors, including structural, electrical, and vascular events. There remains an unmet need to fully elucidate the spectrum of CV events associated with EGFR inhibitors. Early CV screening, close clinical monitoring, coupled with a multidisciplinary approach between medical and cardio-oncology is needed to minimize the potentially detrimental impact of cardiotoxicity in this patient population.

EGFR Exon 20 Insertion Mutations in Sinonasal Squamous Cell Carcinoma

Recurrent epidermal growth factor receptor (EGFR)-activating mutations have been identified in a rare form of head and neck cancer known as sinonasal squamous cell carcinoma (SNSCC), a malignant disease with a 5-year mortality rate of ~40%. Interestingly, the majority of EGFR mutations identified in patients with primary SNSCC are exon 20 insertions (Ex20ins), which is in contrast to non-small-cell lung cancer (NSCLC), where the EGFR exon 19 deletion and L858R mutations predominate. These studies demonstrate that EGFR Ex20ins mutations are not exclusive to lung cancer as previously believed, but are also involved in driving SNSCC pathogenesis. Here we review the landscape of EGFR mutations in SNSCC, with a particular focus on SNSCC associated with inverted sinonasal papilloma (ISP), a benign epithelial neoplasm. Taking lessons from NSCLC, we also discuss potential new treatment options for ISP-associated SNSCC harbouring EGFR Ex20ins in the context of targeted therapies, drug resistance and precision cancer medicine. Moving forward, further basic and translational work is needed to delineate the biology of EGFR Ex20ins in SNSCC in order to develop more effective treatments for patients with this rare disease.

EGFR and HER2 exon 20 insertions in solid tumours: from biology to treatment

Protein tyrosine kinases of the human epidermal growth factor receptor family, including EGFR and HER2, have emerged as important therapeutic targets in non-small-cell lung, breast and gastroesophageal cancers, and are of relevance for the treatment of various other malignancies (particularly colorectal cancer). Classic activating EGFR exon 19 deletions and exon 21 mutations, and HER2 amplification and/or overexpression, are predictive of response to matched molecularly targeted therapies, translating into favourable objective response rates and survival outcomes. By comparison, cancers with insertion mutations in exon 20 of either EGFR or HER2 are considerably less sensitive to the currently available tyrosine kinase inhibitors and antibodies targeting these receptors. These exon 20 insertions are structurally distinct from other EGFR and HER2 mutations, providing an explanation for this lack of sensitivity. In this Review, we first discuss the prevalence and pan-cancer distribution of EGFR and HER2 exon 20 insertions, their biology and detection, and associated responses to current molecularly targeted therapies and immunotherapies. We then focus on novel approaches that are being developed to more effectively target tumours driven by these non-classic EGFR and HER2 alterations.

Amivantamab for the treatment of EGFR exon 20 insertion mutant non-small cell lung cancer

INTRODUCTION

Amivantamab is a monoclonal bispecific anti-EGFR-MET antibody that is the first targeted therapy to be approved for non-small cell lung cancer (NSCLC) patients harboring EGFR exon 20 insertion mutations following progression on chemotherapy, marking a watershed moment for a class of mutations which is generally associated with poor outcomes.

AREAS COVERED

In this article, we outline the drug profile of amivantamab compared with EGFR kinase inhibitors under evaluation in EGFR exon 20 insertion mutant NSCLC. We also review the efficacy and safety data reported from the CHRYSALIS phase I trial, which forms the basis of the recent approval of amivantamab.

EXPERT OPINION

Unlike small molecule EGFR kinase inhibitors, amivantamab has an extracellular mode of action and dual activity against EGFR and MET. It remains to be determined what role MET inhibition plays in toxicity and efficacy and whether dual target inhibition can delay the onset of drug resistance in these cancers. Due to its large molecular size, amivantamab is expected to have poor activity to treat brain metastases. Building on the clinical data so far, future trials that will evaluate combination treatments with brain-penetrant EGFR kinase inhibitors will be critical to move the drug toward a first-line treatment.

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.

Treatment Outcomes and Safety of Mobocertinib in Platinum-Pretreated Patients With EGFR Exon 20 Insertion-Positive Metastatic Non-Small Cell Lung Cancer: A Phase 1/2 Open-label Nonrandomized Clinical Trial

IMPORTANCE

Metastatic non-small cell lung cancer (mNSCLC) with EGFR exon 20 insertion (EGFRex20ins) mutations is associated with a poor prognosis. Mobocertinib is an oral tyrosine kinase inhibitor designed to selectively target EGFRex20ins mutations.

OBJECTIVE

To evaluate treatment outcomes and safety of mobocertinib in patients with previously treated EGFRex20ins-positive mNSCLC.

DESIGN, SETTING, AND PARTICIPANTS

This 3-part, open-label, phase 1/2 nonrandomized clinical trial with dose-escalation/dose-expansion cohorts (28 sites in the US) and a single-arm extension cohort (EXCLAIM; 40 sites in Asia, Europe, and North America) was conducted between June 2016 and November 2020 (data cutoff date). The primary analysis populations were the platinum-pretreated patients (PPP) cohort and the EXCLAIM cohort. The PPP cohort included 114 patients with platinum-pretreated EGFRex20ins-positive mNSCLC who received mobocertinib 160 mg once daily from the dose-escalation (n = 6), dose-expansion (n = 22), and EXCLAIM (n = 86) cohorts. The EXCLAIM cohort included 96 patients with previously treated EGFRex20ins-positive mNSCLC (10 were not platinum pretreated and thus were excluded from the PPP cohort).

INTERVENTIONS

Mobocertinib 160 mg once daily.

MAIN OUTCOMES AND MEASURES

The primary end point of the PPP and EXCLAIM cohorts was confirmed objective response rate (ORR) assessed by independent review committee (IRC). Secondary end points included confirmed ORR by investigator, duration of response, progression-free survival, overall survival, and safety.

RESULTS

Among the PPP (n = 114) and EXCLAIM (n = 96) cohorts, the median (range) age was 60 (27-84) and 59 (27-80) years, respectively; most patients were women (75 [66%] and 62 [65%], respectively) and of Asian race (68 [60%] and 66 [69%], respectively). At data cutoff, median follow-up was 14.2 months in the PPP cohort (median 2 prior anticancer regimens; 40 [35%] had baseline brain metastases), with confirmed ORR of 28% (95% CI, 20%-37%) by IRC assessment and 35% (95% CI, 26%-45%) by investigator assessment; median duration of response by IRC assessment was 17.5 months (95% CI, 7.4-20.3). Median progression-free survival by IRC assessment was 7.3 months (95% CI, 5.5-9.2). Median overall survival was 24.0 months (95% CI, 14.6-28.8). In the EXCLAIM cohort, median follow-up was 13.0 months, with confirmed ORR by IRC assessment of 25% (95% CI, 17%-35%) and by investigator assessment of 32% (95% CI, 23%-43%). The most common treatment-related adverse events were diarrhea and rash.

CONCLUSIONS AND RELEVANCE

In this open-label, phase 1/2 nonrandomized clinical trial, mobocertinib was associated with clinically meaningful benefit in patients with previously treated EGFRex20ins-positive mNSCLC, with a manageable safety profile.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02716116.

Testing for EGFR Mutations and ALK Rearrangements in Advanced Non-Small-Cell Lung Cancer: Considerations for Countries in Emerging Markets

The treatment of patients with advanced non-small-cell lung cancer (NSCLC) in recent years has been increasingly guided by biomarker testing. Testing has centered on driver genetic alterations involving the epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) rearrangements. The presence of these mutations is predictive of response to targeted therapies such as EGFR tyrosine kinase inhibitors (TKIs) and ALK TKIs. However, there are substantial challenges for the implementation of biomarker testing, particularly in emerging countries. Understanding the barriers to testing in NSCLC will be key to improving molecular testing rates worldwide and patient outcomes as a result. In this article, we review EGFR mutations and ALK rearrangements as predictive biomarkers for NSCLC, discuss a selection of appropriate tests and review the literature with respect to the global uptake of EGFR and ALK testing. To help improve testing rates and unify procedures, we review our experiences with biomarker testing in China, South Korea, Russia, Turkey, Brazil, Argentina and Mexico, and propose a set of recommendations that pathologists from emerging countries can apply to assist with the diagnosis of NSCLC.

Targeted therapy in advanced non-small cell lung cancer: current advances and future trends

Lung cancer remains the leading cause of cancer-related mortality in both men and women in the US and worldwide. Non-small cell lung cancer is the most common variety accounting for 84% of the cases. For a subset of patients with actionable mutations, targeted therapy continues to provide durable responses. Advances in molecular and immunohistochemical techniques have made it possible to usher lung cancer into the era of personalized medicine, with the patient getting individualized treatment based on these markers. This review summarizes the recent advances in advanced NSCLC targeted therapy, focusing on first-in-human and early phase I/II clinical trials in patients with advanced disease. We have divided our discussion into different topics based on these agents' mechanisms of action. This article is aimed to be the most current review of available and upcoming targeted NSCLC treatment options. We will also summarize the currently available phase I/II clinical trial for NSCLC patients at the end of each section.