Maintenance Therapy and Advanced Non–Small-Cell Lung Cancer: A Skeptic's View

Olaparib maintenance versus placebo in platinum-sensitive non-small cell lung cancer: the Phase 2 randomized PIPSeN trial

BACKGROUND

Platinum-sensitivity is a phenotypic biomarker of Poly (ADP-ribose) polymerase inhibitors (PARPi) sensitivity in histotypes where PARPi are approved. Approximately one-third of non-small cell lung cancers (NSCLC) are platinum-sensitive. The double-blind, randomized phase II PIPSeN (NCT02679963) study evaluated olaparib, a PARPi, as maintenance therapy for patients with platinum-sensitive advanced NSCLC.

METHODS

Chemonaïve patients with ECOG performance status of 0-1, platinum-sensitive, EGFR- and ALK-wild-type, stage IIIB-IV NSCLC were randomized (R) to receive either olaparib (O) maintenance or a placebo (P). The primary objective was progression-free survival (PFS) from R. Secondary objectives included overall survival (OS) and safety. With an anticipated hazard ratio of 0.65, 144 patients were required to be randomized, and approximately 500 patients enrolled.

RESULTS

The trial was prematurely terminated because anti-PD(L)1 therapy was approved during the trial recruitment. A total of 182 patients were enrolled, with 60 patients randomized: 33 and 27 in the O and P arms, respectively. Patient and tumor characteristics were well-balanced between arms, except for alcohol intake (33% vs 11% in the O and P arms, respectively, p = 0.043). The median PFS was 2.9 and 2.0 months in the O and P arms, respectively (logrank p = 0.99). The median OS was 9.4 and 9.5 months in the O and P arms, respectively (p = 0.28). Grade ≥3 toxicities occurred in 15 and 8 patients in O and P arms, with no new safety concerns.

CONCLUSION

PIPSeN was terminated early after enrollment of only 50% of the pre-planned population, thus being statistically underpowered. Olaparib maintenance did neither improve median PFS nor OS in this patient population.

Metastasis manners and the underlying mechanisms of ALK and ROS1 rearrangement lung cancer and current possible therapeutic strategies

The rearrangements of anaplastic lymphoma kinase (ALK) and the c-ros oncogene 1 (ROS1) have both been important driving factors in non-small-cell lung cancer (NSCLC). They have already been defined in 3-5% of NSCLC patients. ALK and ROS1 rearrangements are associated with unique clinical and pathological features, especially patients are usually younger, with milder or never smoking history, and adenocarcinoma histology. Also, they have both been found to contribute to the metastasis of NSCLC by cell migration and invasion. It has recently been recognized that the brain can be considered as a primary site for metastasis in cancers with ALK or ROS1 rearrangements. The present review summarizes the current status of NSCLC metastasis and possible mechanisms based on available evidence, and then we list possible therapeutic strategies so that an increase in control of ALK and ROS1 rearrangement of NSCLC metastases by combination therapy can be translated in an increase in overall survival and prognosis.

Wanna Get Away? Maintenance Treatments and Chemotherapy Holidays in Gynecologic Cancers

Epithelial ovarian cancer has a very high rate of relapse after primary therapy; historically approximately 70% of patients with a complete clinical response to surgery and adjuvant chemotherapy will relapse and die of the disease. Although this number has slowly improved, cure rates remain less than 50%. As such, maintenance therapy with the aim of preventing or delaying disease relapse and the goal of improving overall survival has been the subject of intense study. Numerous earlier studies with agents ranging from radioactive phosphorus to extended frontline therapy or to monthly taxol administration demonstrated encouraging improvements in progression-free survival (PFS) only to find, disappointingly, no benefit in overall survival. In addition, the PFS advantage of maintenance therapy was associated with disconcerting side effects such that maintenance therapy was not adapted as standard of care. Studies with bevacizumab and PARP inhibitors have demonstrated a PFS advantage with a manageable side-effect profile. However, an overall survival advantage remains unclear, and the use of these approaches thus remains controversial. Furthermore, in recurrent disease, the length of chemotherapy and benefits of extended chemotherapy is unclear. Thus, additional trials assessing maintenance strategies in ovarian and other gynecologic malignancies are needed.

Assessing Therapeutic Efficacy of MEK Inhibition in a KRASG12C-Driven Mouse Model of Lung Cancer

Purpose: Despite the challenge to directly target mutant KRAS due to its high GTP affinity, some agents are under development against downstream signaling pathways, such as MEK inhibitors. However, it remains controversial whether MEK inhibitors can boost current chemotherapy in KRAS-mutant lung tumors in clinic. Considering the genomic heterogeneity among patients with lung cancer, it is valuable to test potential therapeutics in KRAS mutation-driven mouse models.Experimental Design: We first compared the pERK1/2 level in lung cancer samples with different KRAS substitutions and generated a new genetically engineered mouse model whose tumor was driven by KRAS G12C, the most common KRAS mutation in lung cancer. Next, we evaluated the efficacy of selumetinib or its combination with chemotherapy, in KRASG12C tumors compared with KRASG12D tumors. Moreover, we generated KRASG12C/p53R270H model to explore the role of a dominant negative p53 mutation detected in patients in responsiveness to MEK inhibition.Results: We determined higher pERK1/2 in KRASG12C lung tumors compared with KRASG12D Using mouse models, we further identified that KRASG12C tumors are significantly more sensitive to selumetinib compared with KrasG12D tumors. MEK inhibition significantly increased chemotherapeutic efficacy and progression-free survival of KRASG12C mice. Interestingly, p53 co-mutation rendered KRASG12C lung tumors less sensitive to combination treatment with selumetinib and chemotherapy.Conclusions: Our data demonstrate that unique KRAS mutations and concurrent mutations in tumor-suppressor genes are important factors for lung tumor responses to MEK inhibitor. Our preclinical study supports further clinical evaluation of combined MEK inhibition and chemotherapy for lung cancer patients harboring KRAS G12C and wild-type p53 status. Clin Cancer Res; 24(19); 4854-64. ©2018 AACR.

Maintenance Sunitinib following Initial Platinum-Based Combination Chemotherapy in Advanced-Stage IIIB/IV Non-Small Cell Lung Cancer: A Randomized, Double-Blind, Placebo-Controlled Phase III Study-CALGB 30607 (Alliance)

INTRODUCTION

The aim of this study was to evaluate efficacy of maintenance sunitinib after first-line chemotherapy for stage IIIB/IV NSCLC.

METHODS

Cancer and Leukemia Group B 30607 trial was a randomized, double-blind, placebo-controlled, phase III study that enrolled patients without progression after four cycles of first-line platinum-based doublet chemotherapy with or without bevacizumab. Bevacizumab was allowed only during the four cycles of chemotherapy. Patients were randomized to receive sunitinib, 37.5 mg/d, or placebo and were treated until unacceptable adverse event(s), progression, or death. The primary end point was progression-free survival (PFS).

RESULTS

A total of 210 patients were enrolled, randomized, and included in the intent-to-treat analysis. Ten patients did not receive maintenance therapy (four who received placebo and six who received sunitinib). Grade 3/4 adverse events affecting more than 5% of the patients were fatigue (25%), thrombocytopenia (12%), hypertension (12%), rash (11%), mucositis (11%), neutropenia (7%), and anemia (6%) for sunitinib and none for placebo. There were three grade 5 events in patients receiving sunitinib (one pulmonary hemorrhage, one other pulmonary event, and one death not associated with a Common Terminology Criteria for Adverse Events term) and two grade 5 events in patients receiving placebo (one other pulmonary event and one thromboembolism). Median PFS was 4.3 months for sunitinib and 2.6 months for placebo (hazard ratio = 0.62, 95% confidence interval: 0.47-0.82, p = 0.0006). Median overall survival was 11.7 months for sunitinib versus 12.1 months for placebo (hazard ratio = 0.98, 95% confidence interval: 0.73-1.31, p = 0.89).

CONCLUSIONS

Maintenance sunitinib was safe and improved PFS as maintenance therapy in stage IIIB/IV NSCLC but had no impact on overall survival. There is no room for future investigations of sunitinib in this setting.

Maintenance sunitinib for extensive-stage small cell lung cancer: a new standard, an option or a step in the right direction?

Systemic treatment for extensive-stage small cell lung cancer (ES-SCLC) has been stagnant for several decades. Sunitinib is a small molecule that inhibits a variety of receptor tyrosine kinases relevant in tumor biology. CALGB (Alliance) 30504 is a phase II study that investigated the use of maintenance sunitinib vs. placebo in patients with ES-SCLC after treatment with induction platinum/etoposide chemotherapy. The trial met its primary endpoint with an improvement in median progression free survival (PFS) of 1.6 months over placebo. Toxicity included grade 3 fatigue in 19% of patients. Although PFS may be a meaningful endpoint in this patient population, the modest improvement in PFS identified with maintenance sunitinib combined with the toxicity profile would not change the current standard of care. Changes in future trial design may enhance the ability to identify agents that will preserve patient functionality and prolong survival.

Quality of Life in Patients with NSCLC Receiving Maintenance Therapy

Introduction: In the past few years many trials have evaluated the use of maintenance therapy in the treatment of NSCLC stage IV. Both switch as well as continuation maintenance show an improved PFS and overall survival. HRQoL data was only partially published. The aim of this article is to review the published effects of maintenance therapy on HRQoL. Methods: Two PubMed searches were performed using the terms: “maintenance therapy and NSCLC” and “maintenance therapy and NSCLC and HRQoL”. The published data was compared, analysed and evaluated. Results: 272 articles were found dealing with maintenance therapy, and of these 85 articles were found regarding maintenance therapy and HRQoL in NSCLC. Maintenance therapy showed no negative impact on HRQoL but failed to show a real benefit. Some symptoms showed positive trends during maintenance therapy. HRQoL can be used to select patients for maintenance therapy. Conclusions: Maintenance therapy is very safe, improves PFS and OS without impairing HRQoL. Although a positive impact on general QoL could not be demonstrated this is possibly due to the mode of evaluating HRQoL. Patient reported outcomes should be simplified and examined for a longer period of time.

PARAMOUNT: Descriptive subgroup analyses of final overall survival for the phase III study of maintenance pemetrexed versus placebo following induction treatment with pemetrexed plus cisplatin for advanced nonsquamous non-small-cell lung cancer

INTRODUCTION

The PARAMOUNT phase III trial demonstrated that pemetrexed continuation maintenance significantly reduced the risk of disease progression (hazard ratio = 0.62) and death (hazard ratio = 0.78) versus placebo in patients with advanced nonsquamous non-small-cell lung cancer. To further understand the survival data, descriptive subgroup analyses were undertaken.

METHODS

Nine hundred thirty-nine patients received induction therapy (four 21-day cycles pemetrexed 500 mg/m and cisplatin 75 mg/m), after which 539 nonprogressing patients with an Eastern Cooperative Oncology Group performance status (PS) of 0/1 were randomized (2:1) to maintenance pemetrexed (500 mg/m) cycles or placebo until disease progression.

RESULTS

Baseline characteristics of patients surviving for longer periods were comparable to patients surviving shorter periods, suggesting overall survival (OS) benefit for all subgroups of patients on maintenance therapy. An examination of type and severity of induction adverse events also found no association with survival duration. Response to induction (tumor response versus stable disease) was not determinate of pemetrexed maintenance OS outcome as assessed by waterfall plot and scattergrams and by the distribution of patients among various OS intervals. The length of the interval before beginning maintenance therapy (<7 days versus ≥7/≤30 days) also did not impact the survival results. PS, a known prognostic factor, was the only baseline characteristic associated with improved OS; however, both PS 0 and PS 1 patients exhibited a survival benefit from pemetrexed maintenance.

CONCLUSIONS

In PARAMOUNT, the OS benefit was seen across all subgroups. Other than PS, no baseline or clinical parameter clearly identified a subgroup more likely to benefit. Maintenance treatment decisions should be made on an individual basis.

Pemetrexed induces S-phase arrest and apoptosis via a deregulated activation of Akt signaling pathway

Pemetrexed is approved for first-line and maintenance treatment of patients with advanced or metastatic non-small-cell lung cancer (NSCLC). The protein kinase Akt/protein kinase B is a well-known regulator of cell survival which is activated by pemetrexed, but its role in pemetrexed-mediated cell death and its molecular mechanisms are unclear. This study showed that stimulation with pemetrexed induced S-phase arrest and cell apoptosis and a parallel increase in sustained Akt phosphorylation and nuclear accumulation in the NSCLC A549 cell line. Inhibition of Akt expression by Akt specific siRNA blocked S-phase arrest and protected cells from apoptosis, indicating an unexpected proapoptotic role of Akt in the pemetrexed-mediated toxicity. Treatment of A549 cells with pharmacological inhibitors of phosphatidylinositol 3-kinase (PI3K), wortmannin and Ly294002, similarly inhibited pemetrexed-induced S-phase arrest and apoptosis and Akt phosphorylation, indicating that PI3K is an upstream mediator of Akt and is involved in pemetrexed-mediated cell death. Previously, we identified cyclin A-associated cyclin-dependent kinase 2 (Cdk2) as the principal kinase that was required for pemetrexed-induced S-phase arrest and apoptosis. The current study showed that inhibition of Akt function and expression by pharmacological inhibitors as well as Akt siRNA drastically inhibited cyclin A/Cdk2 activation. These pemetrexed-mediated biological and molecular events were also observed in a H1299 cell line. Overall, our results indicate that, in contrast to its normal prosurvival role, the activated Akt plays a proapoptotic role in pemetrexed-mediated S-phase arrest and cell death through a mechanism that involves Cdk2/cyclin A activation.

Targeted therapy for non-small-cell lung cancer: past, present and future

Therapy for advanced non-small-cell lung cancer has developed significantly with new awareness of histologic subtype as an important factor in guiding treatment and the development of targeted agents for molecular subgroups harboring critical mutations that spur on cancer growth. In this comprehensive review, we look back at developments in targeted therapy for advanced non-small-cell lung cancer, reviewing in detail efforts, both successful and in some cases less so, to target EGFR, VEGF and ALK. This review provides an overview of where the field stands at present and the areas we feel are most likely to provide challenges and potential successes in the next 5 years including immune checkpoint inhibition, epigenetic therapy and driver mutation targeting.

50 Years of progress in the systemic therapy of non-small cell lung cancer

Non-small cell lung cancer constitutes 85% to 90% of lung cancer and is the most common cause of cancer death. Over the past 50 years, substantial progress has been made in all aspects of lung cancer including screening, diagnostic evaluation, surgery, radiation therapy, and chemotherapy. This review focuses on the advances in systemic therapy during this half century.

Chemotherapy and targeted therapeutics as maintenance of response in advanced non-small cell lung cancer

Non-small cell lung cancer (NSCLC) remains the most common cause of cancer-related death in the United States. Survival for patients with advanced disease remains meager with standard platinum-based doublet therapy even given initially. Improved efficacy and tolerability of third-generation chemotherapies and small-molecule inhibitors has prompted the evaluation of these agents in the maintenance setting in order to enhance current outcomes. Two separate strategies have evolved: the introduction of a non-cross-resistant drug immediately following first-line or induction chemotherapy (switch maintenance), or the continuation of the non-platinum partner initially introduced during induction (continuation maintenance). Here we review the available clinical trial data evaluating both maintenance strategies, and offer our assessment of their contemporary clinical implications and cost-effectiveness.

Management of non-small-cell lung cancer: recent developments

Non-small-cell lung cancer is one of the leading causes of deaths from cancer worldwide. Therefore, improvements in diagnostics and treatments are urgently needed. In this review, we will discuss the evolution of lung cancer staging towards more non-invasive, endoscopy-based, and image-based methods, and the development of stage-adapted treatment. A special focus will be placed on the role of novel surgical approaches and modern radiotherapy strategies for early stages of disease, the effect of multimodal treatment in locally advanced disease, and ongoing developments in the treatment of patients with metastatic disease. In particular, we will include an emphasis on targeted therapies, which are based on the assumption that a treatable driver mutation or gene rearrangement is present within the tumour. Finally, the position of lung cancer treatment on the pathway to personalised therapy will be discussed.

Identifying the target NSCLC patient for maintenance therapy: an analysis from a placebo-controlled, phase III trial of maintenance pemetrexed (H3E-MC-JMEN)

Background

This was a post hoc analysis of patients with non-squamous histology from a phase III maintenance pemetrexed study in advanced non-small cell lung cancer (NSCLC).

Patients and methods

The six symptom items' [average symptom burden index (ASBI)] mean at baseline was calculated using the lung cancer symptom scale (LCSS). Low and high symptom burden (LSB, ASBI < 25; HSB, ASBI ≥ 25) and performance status (PS: 0, 1) subgroups were analyzed for treatment effect on progression-free survival (PFS) and overall survival (OS) using the Cox proportional hazard models adjusted for demographic/clinical factors.

Results

Significantly longer PFS and OS for pemetrexed versus placebo occurred in LSB patients [PFS: median 5.1 versus 2.4 months, hazard ratio (HR) 0.49, P < 0.0001; OS: median 17.5 versus 11.0 months, HR 0.63, P = 0.0012] and PS 0 patients (PFS: median 5.5 versus 1.7 months, HR 0.36, P < 0.0001; OS: median 17.7 versus 10.3 months, HR 0.54, P = 0.0019). Significantly longer PFS, but not OS, occurred in HSB patients (median 3.7 versus 2.8 months, HR 0.50, P = 0.0033) and PS 1 patients (median 4.4 versus 2.8 months, HR 0.60, P = 0.0002).

Conclusions

ASBI and PS are associated with survival for non-squamous NSCLC patients, suggesting that maintenance pemetrexed is useful for LSB or PS 0 patients following induction.

Systemic therapy of advanced non-small cell lung cancer: major-developments of the last 5-years

The standard palliative treatment for advanced stage NSCLC remains a platinum doublet but by tailoring chemotherapy according to tumour histology the results can be improved through using pemetrexed-containing schemas in non-squamous-cell disease. In addition, maintenance chemotherapy appears to be effective in patients achieving clinical benefit by induction therapy. Targeted therapy based on the presence of activating epidermal growth factor receptor (EGFR) activating mutations or EML4-ALK gene rearrangement is becoming standard practice with high median survival rates, up to 30 months. There are still numerous other molecular targeted drugs in development. This review presents the most recent relevant progress in systemic anti-cancer therapy of advanced NSCLC in the past 5 years and delineates today's new treatment options.