Benefits of Neoadjuvant Chemoimmunotherapy in Early Stage Non Small Cell Lung Cancer

SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2024, about 234,580 new cases of lung cancer will be diagnosed and 125,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer.

The 5-year survival rate for patients diagnosed with lung cancer in the US is about 25%, which is a significant improvement over the past 5 years, in part due to earlier detection from lung cancer screening, reduction in smoking, advances in diagnostic and surgical procedures, as well as the introduction of new therapies. However, the 5-year survival rate remains significantly lower among communities of color at 20%. Early detection and screening remain an important unmet need, as 44% of lung cancer cases are not found until they are advanced. In the US, only 5.8% of those individuals at high risk were screened in 2021.

Approximately 50% of NSCLC patients are diagnosed at an early stage, when surgical resection is a viable treatment option. Among patients with early stage disease, 20% present with Stage I or II disease, while 30% present with Stage IIIA or IIIB disease. These patients are often treated with platinum-based neoadjuvant or adjuvant chemotherapy to eradicate micrometastatic disease and decrease the risk of recurrence. However, conventional neoadjuvant or adjuvant chemotherapy provides only a 5% absolute improvement in Overall Survival (OS) at 5 years and 45-75% of these patients develop recurrent disease. There is therefore an unmet need for this patient population.

Immunotherapy with Immune Checkpoint Inhibitors (ICIs) has revolutionized cancer care and has become one of the most effective treatment options, by improving Overall Response Rate and prolongation of survival, across multiple tumor types. These agents target Programmed cell Death protein-1 (PD-1), Programmed cell Death Ligand-1 (PD-L1), Cytotoxic T-Lymphocyte-Associated protein-4 (CTLA-4), and many other important regulators of the immune system. Checkpoint inhibitors unleash the T cells resulting in T cell proliferation, activation, and a therapeutic response. Biomarkers predicting responses to ICIs include Tumor Mutational Burden (TMB), Mismatch Repair (MMR) status, and Programmed cell Death Ligand 1 (PD‐L1) expression. Combining cytotoxic chemotherapy with a PD-1 inhibitor therapy may augment the antitumor immune response through cell-death induced increased tumor antigenicity and reduction of Treg mediated immune suppression.

Neoadjuvant Immune Checkpoint Inhibitors (ICIs) have emerged as a promising approach to enhance the surgical resectability of tumors and reduce the risk of distant relapse. Clinical trials investigating the combination of neoadjuvant ICIs with platinum-based chemotherapy (ICI-chemotherapy) in resectable NSCLC have demonstrated improvements in Event-Free Survival (EFS) and a notable increase in pathologic Complete Response (pCR), which is considered a potential surrogate for Overall Survival. Consequently, regulatory agencies such as the US FDA and the European Medicines Agency have approved neoadjuvant ICI regimens for resectable NSCLC.

Several studies have suggested greater benefits in EFS and/or pCR in patients with higher PD-L1 expression in tumor cells. As a result, the European Medicines Agency has limited the use of neoadjuvant ICI therapy in combination with platinum-based chemotherapy to NSCLC patients with tumor cell PD-L1 expression of at least 1%. Other factors potentially influencing treatment outcomes include histologic features, disease stage, and smoking history. However, uncertainties remain regarding the necessity of adjuvant postoperative ICI treatment for all patients receiving neoadjuvant ICIs with chemotherapy, and the optimal duration of preoperative treatment.

The researchers therefore conducted a systematic review and meta-analysis of Randomized Clinical Trials with neoadjuvant Immune Checkpoint Inhibitors (ICIs) plus chemotherapy (ICI-chemotherapy) with or without adjuvant ICIs, to evaluate the collective benefits of neoadjuvant ICI-chemotherapy in Event-Free Survival (EFS) and pathologic Complete Response (pCR) among early-stage NSCLC patients, and additionally investigate the impact of various clinical, pathologic, and treatment-related factors. The analysis included 8 Phase II and III Randomized Clinical Trials involving 3387 previously untreated Stage IB-IIIB NSCLC patients. It compared 2-year EFS and pCR rates between patients receiving neoadjuvant chemoimmunotherapy and those patients receiving neoadjuvant chemotherapy alone. The current analysis unlike other meta-analyses that aimed to compare different perioperative ICI-based therapies, focused on limiting heterogeneity and providing consistent and clinically helpful evidence from the subgroup analysis.

The results indicated that neoadjuvant chemoimmunotherapy significantly improved both 2-year EFS and pCR rates, compared to chemotherapy alone. Neoadjuvant chemoimmunotherapy was associated with improved 2-year EFS (HR=0.57; P<0.001) and increased pCR rate (RR=5.58; P<0.001), compared to neoadjuvant chemotherapy alone. This benefit was noted regardless of age, sex, ECOG performance status, smoking history, histologic features including tumor PD=L1 status, tumor stage, type of platinum-compound chemotherapy, number of cycles of neoadjuvant chemoimmunotherapy, or addition of adjuvant Immune Checkpoint Inhibitors. Patients with tumor cells negative for PD-L1 were at higher risk of relapse (HR=0.75), than were those with low PD-L1 (HR=0.61) or high PD-L1 (HR=0.40) and this was statistically significant (P=0.005).

In conclusion, this systemic review and meta-analysis suggests that 3 cycles of neoadjuvant platinum-based Immune Checkpoint Inhibitors plus chemotherapy for early-stage NSCLC patients leads to meaningful improvements in 2-year Event Free Survival and pathologic Complete Response. It underscores the potential of this treatment approach in enhancing outcomes for NSCLC patients and provides valuable insights into optimizing treatment strategies.

Neoadjuvant Chemo-Immunotherapy for Early-Stage Non–Small Cell Lung Cancer; A Systematic Review and Meta-Analysis. Banna GL, Hassan MA, Signori A, et al. JAMA Netw Open. 2024;7(4):e246837. doi:10.1001/jamanetworkopen.2024.6837.

FDA Approves ALECENSA® as Adjuvant Treatment for ALK-Positive Non Small Cell Lung Cancer

SUMMARY: The FDA on April 18, 2024, approved ALECENSA® (Alectinib) for adjuvant treatment following tumor resection in patients with Anaplastic Lymphoma Kinase (ALK)-positive Non Small Cell Lung Cancer (NSCLC), as detected by an FDA-approved test. Lung cancer is the second most common cancer in both men and women and accounts for about 12% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2024 about 234,580 new cases of lung cancer will be diagnosed and about 125,070 patients will die of the disease. Non Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of Non Small Cell Lung Cancer (NSCLC), 25% are Squamous cell carcinomas, 40% are Adenocarcinomas and 10% are Large cell carcinomas.

The discovery of rearrangements of the Anaplastic Lymphoma Kinase (ALK) gene in some patients with advanced NSCLC and adenocarcinoma histology, led to the development of agents such as XALKORI® (Crizotinib), ZYKADIA® (Ceritinib), ALECENSA® (Alectinib), ALUNBRIG® (Brigatinib) and LORBRENA® (Lorlatinib), with promising results. It has become clear that appropriate molecularly targeted therapy for tumors with a molecular abnormality, results in the best outcomes. According to the US Lung Cancer Mutation Consortium (LCMC), two thirds of patients with advanced adenocarcinoma of the lung, have a molecular driver abnormality. The most common oncogenic drivers in patients with advanced adenocarcinoma of the lung are, KRAS in 25%, EGFR in 21% and ALK in 5%, as well as other mutations in BRAF, HER2, AKT1, fusions involving RET and ROS oncogenes and MET gene alterations. These mutations are mutually exclusive and the presence of two simultaneous mutations, are rare.

Patients with ALK-positive NSCLC tend be younger nonsmokers and present with more advanced disease. Approximately 50-60% of these patients develop brain metastases. These patients are often treated with ALK TKIs that cross the blood brain barrier. Patients with early stage resected ALK-positive NSCLC receive adjuvant treatment with platinum-based combination chemotherapy, with 5-year survival ranging from 70% for Stage IB disease to about 35% for Stage IIIA disease, with associated chemotherapy related toxicities.

Alectinib is a potent, second-generation ALK Tyrosine Kinase Inhibitor, and is effective against several ALK mutations that confer resistance to Crizotinib. In the Phase III, randomized ALEX trial, treatment naïve patients with advanced ALK-positive NSCLC who received Alectinib had significantly longer Progression Free Survival and 5-year Overall Survival, compared to those who received Crizotinib, with substantial CNS activity.

The ADAURA trial investigated adjuvant TAGRISSO® (Osimertinib), a third-generation EGFR TKI, in patients with resected EGFR-mutated NSCLC of stage IB, II, or IIIA. Results showed benefits in Disease-Free and Overall Survival, along with reduced CNS recurrence. The ALINA trial similarly assessed the efficacy of Alectinib, in resected ALK-rearranged NSCLC.

ALINA is a global, open-label, randomized, Phase III trial, conducted to investigate the efficacy and safety of adjuvant Alectinib as compared with standard chemotherapy in patients with resected ALK-positive NSCLC. In this study, 257 eligible enrolled patients (N=257) were randomly assigned 4-12 weeks after patients had undergone complete surgical resection (lobectomy, sleeve lobectomy, bilobectomy, or pneumonectomy) in a 1:1 ratio to receive Alectinib 600 mg orally twice daily or platinum-based chemotherapy IV every 21 days for 4 cycles. Alectinib was given for 24 months. Chemotherapy consisted of Cisplatin 75 mg/m2 IV on day 1 of each cycle, plus Vinorelbine 25 mg/m2 IV on days 1 and 8, Gemcitabine 1250 mg/m2 IV on days 1 and 8, or Pemetrexed 500 mg/m2 on day 1. In the event of Cisplatin intolerance, Carboplatin AUC 5 or 6 IV was substituted. Eligible patients had completely resected, histologically confirmed Stage IB (tumors 4 cm or more), II, or IIIA NSCLC, and randomization was stratified according to disease stage and race (Asian versus non-Asian). A total of 231 patients had Stage II or IIIA disease, 116 in the Alectinib group and 115 in the chemotherapy group. The Primary end point was Disease Free Survival (DFS), tested hierarchically among patients with Stage II or IIIA disease and then in the Intention-To-Treat (ITT) population. Secondary end points included CNS Disease Free Survival, Overall Survival, and Safety. The median duration of follow up was 28 months.

The DFS among patients with Stage II or IIIA disease at 2 years was 93.8% in the Alectinib group and 63.0% in the chemotherapy group, and 88.3% and 53.3% respectively at 3 years. The Hazard Ratio for disease recurrence or death was 0.24 (P<0.001), which corresponds to a 76% lower risk with adjuvant Alectinib than with chemotherapy. This DFS benefit was seen consistently across prespecified subgroups, including those defined according to disease stage, race, sex, and smoking status. An exploratory analysis showed a clinically meaningful prolongation of CNS Disease Free Survival with Alectinib. Fewer patients in the Alectinib group had CNS recurrence compared to the chemotherapy group (3.1% versus 11%), consistent with the intracranial efficacy of Alectinib in advanced NSCLC. Overall Survival data were immature at the time of data-cutoff.

The authors concluded that Adjuvant Alectinib significantly improved Disease Free Survival, as compared with platinum-based chemotherapy, among patients with resected ALK-positive NSCLC of Stage IB, II, or IIIA, with few discontinuations due to adverse events. The researchers added that this study reinforces the need for implementation of biomarker testing for ALK alterations, across all stages of NSCLC.

Alectinib in Resected ALK-Positive Non–Small-Cell Lung Cancer. Wu Y-L, Dziadziuszko R, Ahn JS, et al. for the ALINA Investigators. N Engl J Med 2024;390:1265-1276.

FDA Approves RYBREVANT® in Combination with Chemotherapy for Advanced NSCLC with EGFR Exon 20 Insertion Mutations

SUMMARY: The FDA on March 1, 2024, approved Amivantamab-vmjw (RYBREVANT®) with Carboplatin and Pemetrexed for the first-line treatment of locally advanced or metastatic Non-Small Cell Lung Cancer (NSCLC) with Epidermal Growth Factor Receptor (EGFR) exon 20 insertion mutations, as detected by an FDA-approved test. The FDA also granted traditional approval to Amivantamab-vmjw for adult patients with locally advanced or metastatic NSCLC with EGFR exon 20 insertion mutations, as detected by an FDA-approved test, whose disease has progressed on or after platinum-based chemotherapy. FDA previously granted accelerated approval for this indication based on Phase 1 CHRYSALIS study.

The American Cancer Society estimates that for 2024, about 234,580 new cases of lung cancer will be diagnosed and 125,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer.

Approximately 10-15% of Caucasian patients and 35-50% of Asian patients with Adenocarcinomas, harbor activating EGFR mutations, and 90% of these mutations are either exon 19 deletions or L858R substitution mutation in exon 21. EGFR exon 20 insertion mutations are the third most common after L858R and exon 19 deletions and occur in about 2-3% patients with NSCLC and are insensitive to EGFR Tyrosine Kinase Inhibitors (TKIs) due to an altered conformation of the kinase active site. Next-Generation sequencing provides an alternative to Polymerase Chain Reaction (PCR)-based tests, which fail to identify 50% or more of exon 20 insertion mutations. Patients with EGFR exon 20 insertion mutations have a 5-year Overall Survival (OS) of 8% in the frontline setting, compared to an OS of 19% for patients with EGFR exon 19 deletions or L858R mutations. There is therefore a clinically unmet need for this patient group, as there are no approved targeted therapies available, and platinum-doublet chemotherapy remains the standard of care for these patients.

Amivantamab (RYBREVANT®) is a fully human bispecific antibody directed against EGFR and MET receptors, with immune cell-directing activity. Amivantamab binds extracellularly and simultaneously blocks ligand-induced phosphorylation of EGFR and c-MET, inhibiting tumor growth and promoting tumor cell death. Further, Amivantamab downregulates receptor expression on tumor cells thus preventing drug resistance mediated by new emerging mutations of EGFR or c-MET. By binding to the extracellular domain of the receptor protein, Amivantamab can bypass primary and secondary TKI resistance at the active site. Additionally, Amivantamab has been shown to engage macrophages, monocytes, and Natural Killer cells through its Fc domain. Amivantamab in combination with Carboplatin and Pemetrexed demonstrated synergy, with improvement in Response Rates, in previously published studies.

PAPILLON trial is an international, randomized, Phase III study, conducted to assess the efficacy and safety of Amivantamab plus chemotherapy as compared with standard chemotherapy alone, as first-line treatment, in patients with advanced NSCLC with EGFR exon 20 insertions. In this study, 308 patients (N=308) were randomly assigned 1:1 to receive Amivantamab plus chemotherapy (N=153) or chemotherapy alone (N=155), given in 3 week cycles. Amivantamab was given at a dose of 1400 mg (1750 mg for a body weight of 80 kg or more) IV weekly for the first 4 weeks, with the first infusion split over 2 days (at a dose of 350 mg on cycle 1, day 1, and the remainder on cycle 1, day 2). Starting at cycle 3 (week 7), the dose of Amivantamab was increased to 1750 mg IV (2100 mg for a body weight of 80 kg or more) administered every 3 weeks until disease progression. Carboplatin was administered at AUC 5 IV every 3 weeks for up to 4 cycles. Pemetrexed was administered at a dose of 500 mg/m2 IV every 3 weeks until disease progression. Both treatment groups were well balanced and the patients mutational status was determined by local testing of tissue samples in 92% of cases, and plasma samples in 8% of cases. Patients with treated brain metastases were eligible if they were asymptomatic. Patients in the chemotherapy group who had disease progression were allowed to cross over to receive Amivantamab monotherapy. The Primary end point was Progression Free Survival (PFS) as determined by Blinded Independent Central Review. Secondary end points included Objective Response Rate (ORR), Overall Survival (OS), Duration of Response and Safety.

At a median follow-up of 14.9 months, the median PFS was significantly longer in the Amivantamab plus Chemotherapy group and was 11.4 months, compared to 6.7 months in the chemotherapy alone group (HR=0.40; P<0.001). At 18 months, the PFS in the Amivantamab plus chemotherapy group was 31% and 3% in the chemotherapy group. The Objective Response was 73% in the Amivantamab plus chemotherapy group and 47% in the chemotherapy alone group (P<0.001). Overall Survival results were immature at the time of current analysis, with a trend toward improvement in Overall Survival despite a high rate of crossover for the control arm (42%).

The most common adverse events associated with Amivantamab plus chemotherapy were reversible hematologic and EGFR-related toxic effects and included rash, nail toxicity, stomatitis, infusion-related reaction, fatigue, diarrhea, nausea and vomiting. Approximately 7% of patients discontinued Amivantamab due to adverse reactions.

It was concluded that Amivantamab in combination with chemotherapy resulted in superior efficacy as compared with chemotherapy alone, in previously untreated advanced NSCLC patients with EGFR exon 20 insertions.

Amivantamab plus Chemotherapy in NSCLC with EGFR Exon 20 Insertions. Zhou C, Tang K-J, Cho BC, et al. for the PAPILLON Investigators. N Engl J Med 2023;389:2039-2051.

Circulating Tumor DNA Can be Used as an Early Marker of Immunotherapy Response

SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2024, about 234,580 new cases of lung cancer will be diagnosed and 125,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas.

Immunotherapy with Immune Checkpoint Inhibitors (ICIs) has revolutionized cancer care and has become one of the most effective treatment options by improving Overall Response Rate and prolongation of survival across multiple tumor types. These agents target Programmed cell Death protein-1 (PD-1), Programmed cell Death Ligand-1 (PD-L1), Cytotoxic T-Lymphocyte-Associated protein-4 (CTLA-4), and many other important regulators of the immune system. Immune Checkpoint Inhibitors enhance antitumor immunity by unleashing the T cells. However, this benefit may vary among patients and tumor types. Biomarkers predicting responses to ICIs include Tumor Mutational Burden (TMB), Mismatch Repair (MMR) status, and Programmed cell Death Ligand 1 (PD‐L1) expression.

First line treatment options for patients with NSCLC include Pembrolizumab as a single agent or a combination Pembrolizumab with Carboplatin and Taxane/Pemetrexed. However, it remains unclear which patients would benefit from Pembrolizumab monotherapy and which group should receive combination immuno/chemotherapy. Further, such therapeutic decisions are not currently supported by either tumor PD-L1 or TMB status. There is therefore an urgent unmet need to implement molecular response-driven approaches to guide therapy selection in the immunotherapy space. Liquid biopsy analyses of circulating cell-free tumor DNA (ctDNA) can capture the tumor burden dynamics during immune checkpoint blockade, and may help guide therapy, to maximize therapeutic benefit and minimize toxicities to patients.

The Canadian Cancer Trials Group (CCTG) BR.36 is an international, multi-center, open-label, biomarker-directed Phase II trial, designed to establish the role of circulating tumor DNA (ctDNA) as a potential early measurement of immunotherapy response, in patients with advanced NSCLC. The trial design consists of two stages. In Stage 1 (observational), the objectives were to ascertain ctDNA response and determine optimal timing and concordance with radiologic Response Evaluation Criteria in Solid Tumors (RECIST) response. The researchers in this publication reported the findings of the First stage (Stage 1). The Second stage of the trial (Stage 2) will evaluate the potential clinical benefit of tailoring treatment to ctDNA molecular response (whether adding chemotherapy to Pembrolizumab for patients with advanced PD-L1+NSCLC who have persistent ctDNA at 6 weeks will result in better Progression Free Survival (PFS) and Overall Survival (OS) compared to patients who remain on Pembrolizumab therapy until clinical progression).

The first stage (observational stage) of the BR.36 trial enrolled 50 patients with advanced/metastatic NSCLC who did not harbor clinically actionable genomic alterations in EGFR or ALK, and had a PD-L1 expression level of 1% or more. Majority of patients had Stage IV NSCLC (98%) and had no prior systemic therapy (92%), 82% were white, 52% female and 56% were 65 years or older, 76% tumors were adenocarcinomas, and 96% had a PD-L1 Tumor Proportion Score (TPS) of 50% or more.

Patients received Pembrolizumab as per local standard of care, and radiographic response assessments were performed per RECIST criteria every 6 weeks until week 12 and at longer intervals thereafter. Serial liquid biopsies were collected and ctDNA molecular response assessments were performed before treatment administration on C1D1 (baseline), C2D1 (3 weeks) and C3D1 (6 weeks). Molecular response was defined as maximal mutant allele fraction clearance at the third cycle of Pembrolizumab. The Primary endpoint of the trial was to determine the optimal time point of ctDNA molecular response, and validate the concordance of ctDNA molecular response with radiographic response. Secondary endpoints included the evaluation of time to ctDNA response, and correlation with Progression Free and Overall Survival. The median follow up time was 13.5 months, and of the 45 patients evaluable for both radiographic and ctDNA responses, 10 patients had undetectable ctDNA, which is consistent with previously reported ctDNA undetectable rate in patients with metastatic NSCLC.

The trial met its Primary endpoint, and the concordance between ctDNA and radiographic response in terms of sensitivity was 82%, and 75% for specificity. The median time to ctDNA response was 2.1 months, and patients with molecular response attained longer Progression Free Survival (5.03 months versus 2.6 months) and Overall Survival (Not Reached versus 7.23 months). These findings are incorporated into the second stage of the BR.36 trial in which patients at risk of progression are randomized to treatment intensification or continuation of therapy.

It was concluded from the first stage of the BR.36 trial that ctDNA analyses can be used as an early marker of immunotherapy response and has the potential to determine the early efficacy of investigational agents in clinical trials. The second stage of this study will assess whether outcomes can be improved in those metastatic NSCLC tumors expressing PD-L1 with ctDNA response, by continuation of Pembrolizumab or adding chemotherapy to immunotherapy.

ctDNA response after pembrolizumab in non-small cell lung cancer: phase 2 adaptive trial results. Anagnostou, V., Ho, C., Nicholas, G. et al. Nat Med 2023;29: 2559–2569. https://doi.org/10.1038/s41591-023-02598-9

FDA Approves AUGTYRO® for ROS1-positive Non-Small Cell Lung Cancer

SUMMARY: The FDA on November 15, 2023, approved AUGTYRO® (Repotrectinib) for locally advanced or metastatic ROS1-positive Non-Small Cell Lung Cancer (NSCLC). This is the first FDA approval that includes patients with ROS1-positive NSCLC who have previously received a ROS1 Tyrosine Kinase Inhibitor (TKI), in addition to patients who are TKI naïve.

Approximately 1-2% of lung adenocarcinomas harbor ROS1 gene rearrangements. ROS1 gene is located on chromosome 6q22 (long arm of chromosome 6) and plays an important role in cell growth and development. ROS1 gene fusion with another gene results in a mutated DNA sequence which then produces an abnormal protein responsible for unregulated cell growth and cancer. ROS1 gene rearrangement has been identified as a driver mutation in Non Small Cell Lung Cancer with adenocarcinoma histology. This is more common in nonsmokers or in light smokers (<10 pack years) who are relatively young (average age of 50 years), and thus share similar characteristics with ALK-positive patients. ROS1 mutations have been also been associated with Cholangiocarcinoma (Bile duct cancer) and Glioblastoma multiforme. ROS1 rearrangements are mutually exclusive with other oncogenic mutations found in NSCLC such as EGFR mutations, KRAS mutations and ALK rearrangement. The presence of a ROS1 rearrangement can be detected by Fluorescence In Situ Hybridization (FISH), ImmunoHistoChemistry (IHC), Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) and Next Generation-Sequencing. There are currently two FDA-approved treatment options for ROS1-positive metastatic NSCLC- Crizotinib and Entrectinib.

Repotrectinib is a next-generation TKI targeting ROS1 or NTRK-positive locally advanced or metastatic solid tumors, including NSCLC. Repotrectinib was designed to improve durability of response and with favorable properties to enhance intracranial activity.

The FDA approval was based on the results of the TRIDENT-1 global, multicenter, single-arm, Phase I/II, open-label, multi-cohort clinical trial, designed to evaluate the safety, tolerability, pharmacokinetics, and anti-tumor activity of Repotrectinib, in patients with advanced solid tumors, including locally advanced or metastatic NSCLC. Phase I component of the trial evaluated the safety and pharmacokinetics, whereas in the Phase II component of the study included six distinct expansion cohorts, including TKI-naïve and TKI-pretreated patients with ROS1-positive locally advanced or metastatic NSCLC and NTRK-positive advanced solid tumors. Eligibility requirements included locally advanced or metastatic solid tumors harboring ROS1 or NTRK1-3 gene fusions. Patients with asymptomatic CNS metastases were allowed. Patients received Repotrectinib 160 mg once daily, orally for 14 days, followed by 160 mg twice daily until disease progression or unacceptable toxicities. The Primary endpoint was Overall Response Rate (ORR) as assessed by Blinded Independent Central Review (BICR), and Secondary endpoints included Duration of Response (DOR), Progression Free Survival (PFS), Overall Survival (OS) and Clinical Benefit Rate (CBR). The efficacy was evaluated in ROS1 TKI-naïve patients (N=71) who received up to one prior line of platinum-based chemotherapy and/or immunotherapy, and in patients who received one prior ROS1 TKI with no prior platinum-based chemotherapy or immunotherapy (N=56).

In TKI-naïve patients with median follow-up of 24.0 months, the confirmed Objective Response Rate by BICR was 79%, median Duration of Response was 34.1 months and PFS was 35.7 months. In patients with measurable brain metastases at baseline (N=9), intracranial ORR per BICR was 89% and these responses were prolonged.

In patients who received one prior ROS1 TKI with no prior chemotherapy or immunotherapy, at a median follow-up of 21.5 months, the confirmed Objective Response Rate by BICR was 38%, median Duration of Response was 14.8 months and PFS was 9.0 months. In this subset of patients with measurable brain metastases at baseline (N=13), intracranial ORR per BICR was 38%.

The most common adverse reactions were fatigue, dizziness, dyspnea, dysgeusia, peripheral neuropathy, constipation, ataxia, cognitive disorders, and muscular weakness.

It was concluded that the TRIDENT-1 trial demonstrated the efficacy of Repotrectinib in both, TKI-naïve and previously treated patients, showcasing high response rates and durable outcomes. These data will provide physicians with valuable insights into the clinical benefits with Repotrectinib , paving the way for its potential adoption as a new standard of care, in the treatment of ROS1-positive NSCLC. TRIDENT-1 trial is ongoing to assess long term outcomes and additional endpoints across patient populations with ROS1-positive locally advanced or metastatic NSCLC, and NTRK-positive advanced solid tumors.

Repotrectinib in patients with ROS1 fusion-positive (ROS1+) NSCLC: Update from the pivotal phase 1/2 TRIDENT-1 trial. Cho BC, Camidge DR, Lin JJ, et al. Presented at the IASLC 2023 World Conference on Lung Cancer; September 10-12, 2023; Singapore. Abstract OA03.06.

Osimertinib Plus Chemotherapy Superior to Osimertinib Alone in Advanced EGFR Mutated Non Small Cell Lung Cancer

SUMMARY: Lung cancer is the second most common cancer in both men and women and accounts for about 13% of all new cancers and 21% of all cancer deaths. The American Cancer Society estimates that for 2023, about 238,340 new cases of lung cancer will be diagnosed and 127,070 patients will die of the disease. Lung cancer is the leading cause of cancer-related mortality in the United States. Non-Small Cell Lung Cancer (NSCLC) accounts for approximately 85% of all lung cancers. Of the three main subtypes of NSCLC, 30% are Squamous Cell Carcinomas (SCC), 40% are Adenocarcinomas and 10% are Large Cell Carcinomas. With changes in the cigarette composition and decline in tobacco consumption over the past several decades, Adenocarcinoma now is the most frequent histologic subtype of lung cancer.

Approximately 10-15% of Caucasian patients and 35-50% of Asian patients with Adenocarcinomas, harbor activating EGFR (Epidermal Growth Factor Receptor) mutations and 90% of these mutations are either Exon 19 deletions or L858R substitution mutation in Exon 21. Approximately 25% of patients with EGFR mutated NSCLC have brain metastases at diagnosis, increasing to approximately 40% within two years of diagnosis. The presence of brain metastases often reduces median survival to less than eight months. EGFR-Tyrosine Kinase Inhibitors (TKIs) such as TARCEVA® (Erlotinib), IRESSA® (Gefitinib) and GILOTRIF® (Afatinib), have demonstrated a 60-70% response rate as monotherapy when administered as first line treatment, in patients with metastatic NSCLC, who harbor the sensitizing EGFR mutations. However, majority of these patients experience disease progression within 9-14 months. This resistance to frontline EGFR TKI therapy has been attributed to the most common, acquired T790M “gatekeeper” point mutation in EGFR, identified in 50-60% of patients.

Osimertinib (TAGRISSO®) is a highly selective third-generation, irreversible Epidermal Growth Factor Receptor TKI, presently approved by the FDA, for the first-line treatment of patients with metastatic NSCLC, whose tumors have Exon 19 deletions or Exon 21 L858R mutations, as well as treatment of patients with metastatic EGFR T790M mutation-positive NSCLC, whose disease has progressed on or after EGFR-TKI therapy. Further, Osimertinib has higher CNS penetration and is therefore able to induce responses in 70-90% of patients with brain metastases.

In the Phase III FLAURA trial, among patients with metastatic, EGFR-mutant NSCLC, first-line treatment with Osimertinib significantly improved median Overall Survival, compared with Erlotinib and Gefitinib, and Osimertinib therefore has been the preferred regimen in this patient group. The FLAURA2 trial builds on the favorable results observed in the Phase III FLAURA trial.
FLAURA2 is a randomized, open-label, multi-center, global, ongoing Phase III trial, in which 557 enrolled treatment naïve patients (N=557), with nonsquamous locally advanced (Stage IIIB-IIIC) or metastatic EGFR mutated NSCLC, were randomly assigned 1:1 to receive Osimertinib plus chemotherapy (N=279) or Osimertinib monotherapy (N=278). Patients in the combination group received Osimertinib 80 mg oral tablets once daily in combination with chemotherapy consisting of Pemetrexed 500 mg/m2 IV plus Cisplatin 75 mg/m2 IV or Carboplatin (AUC5), every three weeks for four cycles, followed by Osimertinib with Pemetrexed maintenance every three weeks. The median patient age was 62 years, approximately 62% were women and 64% were Asian. About 61% had Exon 19 deletion and 38% had L858R substitution mutation in Exon 21, 40% had CNS metastases and 53% had extrathoracic metastases. Approximately 76% of patients completed four cycles of platinum therapy. The Primary end point was investigator-assessed Progression Free Survival (PFS). Secondary endpoints included Overall Survival (OS), Objective Response Rate (ORR) and Safety. The median follow-up for progression-free survival was 19.5 months in the osimertinib–chemotherapy group and 16.5 months in the osimertinib group.

In this final analysis of the Primary endpoint of PFS, results from this study showed a significant improvement in PFS with the Osimertinib plus chemotherapy combination versus Osimertinib alone (HR=0.62; P<0.001). The median PFS was 25.5 months versus 16.7 months respectively. This represented a 38% reduction in disease progression risk, compared to Osimertinib monotherapy. The PFS benefit with Osimertinib plus chemotherapy was consistent across prespecified subgroups, including the subgroups defined according to EGFR mutation type and the presence or absence of CNS metastases at baseline. The Objective Response Rate with the combination regimen was 83%, compared to 76%, in the Osimertinib monotherapy group. The median response duration was 24 months and 15.3 months respectively. Grade 3 or higher hematologic adverse events occurred more frequently in the combination regimen group and were manageable. Data for Overall Survival were immature at the time of the analysis, and this ongoing trial will continue to assess the Secondary endpoint of Overall Survival.

The authors concluded that FLAURA2 provides compelling evidence that the addition of chemotherapy to Osimertinib in the first line treatment of nonsquamous, locally advanced or metastatic EGFR mutated NSCLC, can significantly improve outcomes, compared to Osimertinib alone, and can delay resistance to therapy and disease progression.

Osimertinib with or without Chemotherapy in EGFR-Mutated Advanced NSCLC. Planchard D, Jänne PA, Cheng Y, et al. for the FLAURA2 Investigators. N Engl J Med 2023; 389:1935-1948