Sequential afatinib and osimertinib in patients with EGFR mutation-positive non-small-cell lung cancer: updated analysis of the observational GioTag study

Propensity score analysis of overall survival between first- and second-generation EGFR-TKIs using real-world data

We constructed a data set of EGFR‐mutant non–small‐cell lung carcinoma (NSCLC) patients, and compared the overall survival of first‐generation (1G), and second‐generation (2G) EGFR‐tyrosine kinase inhibitors (TKIs) in clinical practice using a propensity score. We reviewed the clinical data of consecutive EGFR‐mutated NSCLC patients who received EGFR‐TKI therapy between January 2008 and August 2017 at 11 institutions in Japan. The primary endpoint was overall survival (OS). When comparing OS between 1G and 2G EGFR‐TKIs, propensity score analyses were performed using 2 methods: matching and inverse probability of treatment weighting (IPTW). (Clinical Trial information: UMIN000030121) In total, 1400 patients from 11 institutions were enrolled in this study, and the data from the 1366 patients who received only EGFR‐TKI therapy were analyzed (gefitinib [GEF], N = 732; erlotinib [ERL], N = 416; afatinib, N = 218). Median OS times (months [95%CI]) were 29.7 [27.5‐33.5] in the 1G group (gefitinib, 32.0 [28.1‐35.8]; erlotinib, 27.5 [23.9‐31.7]), and 38.6 [32.2‐NR] in the 2G group (afatinib), respectively. The trend of longer OS for afatinib against 1G EGFR‐TKIs remained, even after adjusted by propensity score. (unadjusted, hazard ratio [HR] 0.676, P = .0023; adjusted by IPTW, HR 0.685 P < .0001; adjusted by matching, HR 0.725, P = .0418). Exploratory analysis showed that OS using the 2G EGFR‐TKI was superior to that of the 1G EGFR‐TKIs, suggesting the potential of sequential therapy of 2G EGFR‐TKI followed by osimertinib. (HR 0.419, P = .0519) Real‐world data analysis using 1354 data records, using propensity scoring, indicated that 2G EGFR‐TKI had a trend of longer OS compared with 1G EGFR‐TKIs.

Non-small cell lung cancer patients with ex19del or exon 21 L858R mutation: distinct mechanisms, different efficacies to treatments

With the development of antitumor therapies, different treatment methods including monotherapy and combined therapy have achieved clinical efficacy in advanced epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC) patients. Exon 19 deletion (ex19del) and exon 21 L858R mutation are common sensitive subtypes of EGFR mutation. However, potential distinct mechanisms are found from several dimensions including molecular structures, biological behaviors, concomitant mutations, resistance mechanisms and tumor mutation burdens. More evidence indicates the prognostic difference of EGFR subgroups. This review focused on the progress of potential distinct mechanisms and outcomes in clinical trials of advanced NSCLC patients with ex19del or exon 21 L858R mutation.

Afatinib for the treatment of EGFR mutation-positive NSCLC: A review of clinical findings

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors represent the standard of care in patients with EGFR mutation-positive (EGFRm+) non-small cell lung cancer (NSCLC). The availability of several EGFR tyrosine kinase inhibitors approved for use in the first-line or later settings in NSCLC warrants an in-depth understanding of the pharmacological properties of, and clinical data supporting, these agents. The second-generation, irreversible ErbB-family blocker, afatinib, has been extensively studied in the context of EGFRm+ NSCLC. Results from the LUX-Lung 3 and 6 studies showed that afatinib was more active and better tolerated than chemotherapy in patients with tumors harboring EGFR mutations. Subanalysis of these trials, along with real-world data, indicates that afatinib is active in patients with certain uncommon EGFR mutations (S768I/G719X/L861Q) as well as common mutations (Del19/L858R), and in patients with active brain metastases. In LUX-Lung 7, a head-to-head phase IIb trial, afatinib improved progression-free survival and time-to-treatment failure versus the first-generation reversible EGFR tyrosine kinase inhibitor, gefitinib, albeit with a higher incidence of serious treatment-related adverse events. Nevertheless, afatinib is generally well tolerated, and adverse events are manageable through supportive care and a well-defined tolerability-guided dose adjustment scheme. In this review, we provide a detailed overview of the pharmacology, efficacy, and safety of afatinib, discuss treatment sequencing strategies following emergence of different resistance mechanisms, and shed light on the economic impact of afatinib. We also provide a comparison of afatinib with the available EGFR tyrosine kinase inhibitors and discuss its position within treatment strategies for patients with EGFRm+ NSCLC.

Treatment sequence of first and second generation tyrosine kinase inhibitor followed by osimertinib in EGFR-mutated non-small-cell lung cancer: a real life study

Background: We aimed to assess the effectiveness and cost of patients with first line tyrosine kinase inhibitors (TKIs) sequence of first (1G) and second generation (2G) followed by osimertinib. Materials & methods: Using the French nationwide claims and hospitalization database, we analyzed non-small-cell lung cancer patients who had been treated with osimertinib between April 2015 and December 2017, after a first line treatment with a TKI-1G/2G. Results: The median time on treatment for sequential TKI-1G/2G followed by osimertinib was 34 months (95% CI: 31-46); 13 and 12months, respectively for TKI 1G or 2G and TKI 3G, respectively. The median overall survival for sequential TKI 1G or 2G followed by osimertinib was 37 months (95% CI: 34-42). The mean monthly costs per patient was €5162. Conclusion: These results, in line with those observed during clinical trials, confirm the effectiveness of the sequence TKI-1G/2G followed by osimertinib in EGFR-mutated non-small-cell lung cancer.

Is there a role for dacomitinib, a second-generation irreversible inhibitor of the epidermal-growth factor receptor tyrosine kinase, in advanced non-small cell lung cancer?

INTRODUCTION

Non-small cell lung cancer (NSCLC) is a highly lethal disease. During the past 20 years, the epidermal growth factor receptor (EGFR) has been a relevant target for anticancer drug-design, and a large family of EGFR tyrosine kinase inhibitors (TKI) were designed, which improved therapeutic outcomes compared to conventional chemotherapy in NSCLC patients with specific EGFR mutations. However, resistance to these inhibitors occurs; therefore, the debate on which inhibitor should be used first is still open. Dacomitinib was approved in 2018 for the first-line treatment of NSCLC with EGFR activating mutations.

AREAS COVERED

This manuscript reviews the properties of dacomitinib, including the current information from clinical trials and its potential application as stand-alone therapy, or in combination.

EXPERT OPINION

Dacomitinib is a second-generation EGFR-TKI that has demonstrated significant improvement in overall survival in a phase III randomized study compared with gefitinib, a first-generation TKI. However, the rapid development and approval of a new generation of TKIs (osimertinib), with better clinical profiles, raises the question of which role can dacomitinib play in NSCLC. Further studies are required to evaluate the efficacy of this drug on brain metastases, as a second-line treatment after third-generation TKIs, or in combination with other types of treatments.

Canadian consensus: a new systemic treatment algorithm for advanced EGFR-mutated non-small-cell lung cancer

Background

Multiple clinical trials for the treatment of advanced EGFR-mutated non-small-cell lung cancer (nsclc) have recently been reported. As a result, the treatment algorithm has changed, and many important clinical questions have been raised:■ What is the optimal first-line treatment for patients with EGFR-mutated nsclc?■ What is preferred first-line treatment for patients with brain metastasis?■ What is the preferred second-line treatment for patients who received first-line first- or second-generation tyrosine kinase inhibitors (tkis)?■ What is the preferred treatment after osimertinib?■ What evidence do we have for treating patients whose tumours harbour uncommon EGFR mutations?

Methods

A Canadian expert panel was convened to define the key clinical questions, review recent evidence, and discuss and agree on practice recommendations for the treatment of advanced EGFR-mutated nsclc.

Results

The published overall survival results for osimertinib, combined with its central nervous system activity, have led to osimertinib becoming the preferred first-line treatment for patients with common EGFR mutations, including those with brain metastasis. Other agents could still have a role, especially when osimertinib is not available or not tolerated. Treatment in subsequent lines of therapy depends on the first-line therapy or on T790M mutation status. Treatment recommendations for patients whose tumours harbour uncommon EGFR mutations are guided mainly by retrospective and limited prospective evidence. Finally, the evidence for sequencing and combining tkis with chemotherapy, angiogenesis inhibitors, checkpoint inhibitors, and other new therapeutics is reviewed.

Conclusions

This Canadian expert consensus statement and algorithm were driven by significant advances in the treatment of EGFR-mutated nsclc.

Tyrosine Kinase Inhibitors in Cancer: Breakthrough and Challenges of Targeted Therapy

Receptor tyrosine kinases (RTKs) are key regulatory signaling proteins governing cancer cell growth and metastasis. During the last two decades, several molecules targeting RTKs were used in oncology as a first or second line therapy in different types of cancer. However, their effectiveness is limited by the appearance of resistance or adverse effects. In this review, we summarize the main features of RTKs and their inhibitors (RTKIs), their current use in oncology, and mechanisms of resistance. We also describe the technological advances of artificial intelligence, chemoproteomics, and microfluidics in elaborating powerful strategies that could be used in providing more efficient and selective small molecules inhibitors of RTKs. Finally, we discuss the interest of therapeutic combination of different RTKIs or with other molecules for personalized treatments, and the challenge for effective combination with less toxic and off-target effects.

Therapies after first-line afatinib in patients with EGFRm+ NSCLC in Japan: retrospective analysis of LUX-Lung 3

Aim: Acquired resistance to EGFR tyrosine kinase inhibitors is inevitable in non-small-cell lung cancer. To inform subsequent treatment decisions, we retrospectively assessed therapies following afatinib in Japanese patients from LUX-Lung 3. Patients & methods: LUX-Lung 3 was a randomized, open-label, Phase III study of afatinib versus cisplatin/pemetrexed in treatment-naive patients with EGFR mutation-positive ( EGFRm+) advanced lung adenocarcinoma. Results: Among 47 Japanese patients who discontinued first-line afatinib, 91/81/62% received ≥one/two/three subsequent therapies. The most common second-line therapies were platinum-based chemotherapy (38%) and a first-generation EGFR tyrosine kinase inhibitor (17%). Median overall survival (afatinib vs cisplatin/pemetrexed) was 47.8 versus 35.0 months (not significant). Conclusion: First-line afatinib does not appear to diminish suitability for subsequent therapies in EGFRm+ non-small-cell lung cancer.

Observational Study of Sequential Afatinib and Osimertinib in EGFR Mutation-Positive NSCLC: Patients Treated with a 40-mg Starting Dose of Afatinib

Introduction

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are the standard of care for patients with EGFR mutation-positive non-small cell lung cancer (NSCLC). However, questions remain about the optimal treatment sequence of EGFR TKIs. The global, observational GioTag study demonstrated prolonged time on treatment with sequential afatinib and osimertinib therapy in patients who acquired the T790M mutation. Here, we assessed outcomes in patients who received the approved 40-mg starting dose of afatinib, as used in the clinical trial setting.

Methods

In the non-interventional, global, multicenter GioTag study, patients had T790M-positive disease following first-line afatinib and started osimertinib treatment ≥ 10 months prior to data entry. Primary outcome was time on treatment. This subanalysis assessed outcomes in patients who received afatinib 40 mg.

Results

In 169 patients who received an afatinib starting dose of 40 mg, median time on treatment was 27.6 months (90% confidence interval [CI] 26.3–31.3). Benefit was seen across patient subgroups, particularly those with Del19-positive disease and Asian patients; median time on treatment was 29.9 months (90% CI 27.6–46.7) in patients with Del19-positive disease and 46.7 months (90% CI 28.4–not reached) in Asian patients. The 2-year overall survival rate was 80%.

Conclusions

These real-world results support the overall study results and demonstrate prolonged time on treatment with sequential afatinib and osimertinib. The results suggest that sequential afatinib and osimertinib is a feasible therapeutic strategy for patients who acquire the T790M mutation, particularly those with Del19-positive disease or Asian patients.

Trial Registration Number

NCT03370770.

Electronic Supplementary Material

The online version of this article (10.1007/s12325-019-01187-y) contains supplementary material, which is available to authorized users.

Tyrosine Kinase Inhibitors for the Treatment of EGFR Mutation-Positive Non-Small-Cell Lung Cancer: A Clash of the Generations

The availability of 3 generations of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) with different pharmacologic characteristics and clinical profiles has provided oncologists with a potentially confusing choice for the treatment of EGFR mutation-positive non-small-cell lung cancer. Although recent head-to-head clinical trials have demonstrated improved efficacy with second-generation (ie, afatinib, dacomitinib) and third-generation (ie, osimertinib) TKIs compared with the first-generation TKIs (eg, erlotinib, gefitinib), acquired resistance has been inevitable, regardless of which agent has been chosen as first-line therapy. Thus, the potential availability of subsequent treatment options is an important consideration. Recent data have demonstrated that osimertinib confers an overall survival benefit compared with first-generation EGFR TKIs, and dacomitinib has shown an overall survival benefit compared with gefitinib in an exploratory analysis. However, the relative benefits of different sequential EGFR-TKI regimens, especially those involving second- and third-generation agents, have remained uncertain and require prospective evaluation. Few such data currently exist to inform treatment choices. In the present review, we examined the pharmacologic characteristics and current clinical data for EGFR TKIs, including emerging information on the molecular mechanisms of resistance across the different generations of TKIs. Given the uncertainties regarding the optimal treatment choice, we have focused on the factors that might help determine the treatment decisions, such as efficacy and safety in patient subgroups. We also discussed the emerging real-world data, which have provided some insights into the benefits of sequential regimens in everyday clinical practice.

Predictive impact of low-frequency pretreatment T790M mutation in patients with EGFR-mutated non-small cell lung cancer treated with EGFR tyrosine kinase inhibitors

OBJECTIVES

Low-frequency epidermal growth factor receptor (EGFR) T790M mutation could be detected by ultrasensitive methods in EGFR tyrosine kinase inhibitor (TKI)-naïve non-small cell lung cancer (NSCLC). However, the impact of pretreatment T790M (preT790M) on the efficacy of EGFR-TKIs and on resistance remains unclear.

MATERIALS AND METHODS

Two independent cohorts consisting of advanced EGFR-mutated NSCLC patients treated with first-line EGFR-TKIs, a derivation cohort that started treatment between August 2013 and July 2016 (cohort A, n = 44) and a validation cohort between August 2016 and December 2017 (cohort B, n = 22), were examined in this study. Among these, 28 patients underwent re-biopsy at disease progression. DNAs from pretreatment tumor biopsy samples and re-biopsy samples were assessed to detect T790M by the Cobas EGFR Mutation Test v2 (Cobas) and for quantitating T790M by droplet digital polymerase chain reaction (ddPCR).

RESULTS

Detection rates of preT790M were 40.9% (18/44) in cohort A and 45.5% (10/22) in cohort B by ddPCR, and none by Cobas. A cutoff value of 0.3% for dividing into high- vs. low-preT790M allele frequency was determined by receiver operating characteristic curve analysis in cohort A. Progression-free survival (PFS) was significantly shorter in the high- preT790M group (n = 12) than in the low-preT790M (n = 6) and negative (n = 26) groups (combined low-preT790M) (median: 6.9 vs. 13.8 months, P =  0.00073). These observations were validated in cohort B [median: 6.2 (n = 5) vs. 15.3 months (n = 17), P =  0.0029]. In 28 paired biopsies, Cobas detected post-progression T790M in 60% (3/5) of the high-preT790M, in 57% (4/7) of the low-preT790M, and in 56% (9/16) of the negative-preT790M groups.

CONCLUSION

EGFR-mutated NSCLC with high preT790M had significantly shorter PFS on EGFR-TKIs. However, preT790M abundance may not necessarily confer post-TKI T790M resistance.

Optimizing outcomes and treatment sequences in EGFR mutation-positive non-small-cell lung cancer: recent updates

The availability of several EGFR tyrosine kinase inhibitors (TKIs) for the treatment of EGFR mutation-positive NSCLC poses important questions regarding the optimum sequence of therapy. A key consideration is how best to use the third-generation TKI, osimertinib. While osimertinib has demonstrated impressive efficacy and tolerability in a first-line setting, there are currently no standard targeted treatment options following progression. There is an argument, therefore, for reserving osimertinib for second-line use in patients who acquire the T790M resistance mutation after first- or second-generation TKIs. This article reviews recent clinical studies that have assessed the activity of sequential EGFR TKI regimens. These studies support the hypothesis that sequential use of EGFR TKIs represents a viable treatment option in 'real-world' clinical practice.