Efficacy in patients with EGFR-positive non-small-cell lung cancer treated with dacomitinib who had skin adverse events: post hoc analyses from ARCHER 1050.

Aim: We investigated association between skin adverse events (AEs) and efficacy with dacomitinib in patients with EGFR-positive non-small-cell lung cancer (NSCLC).Methods: Post hoc analyses from ARCHER 1050 evaluated efficacy in patients who did and did not experience grade ≥2 skin AEs with dacomitinib. Landmark analyses were performed at 3 and 6 months.Results: In patients who had skin AEs (72.2%) vs. those who did not (27.7%), median progression-free survival was 16.0 vs. 9.2 months, median overall survival (OS) was 37.7 vs. 21.6 months, and objective response rate was 80.2 vs. 61.5%; OS was improved at 3 and 6 months landmark analyses.Conclusion: Presence of grade ≥2 skin AEs was associated with numerically improved efficacy and represents a valuable biomarker of treatment outcome with dacomitinib in patients with advanced NSCLC.Clinical Trial Registration: NCT01774721 (ClinicalTrials.gov).

The ARCHER 1050 study assessed how the drugs called dacomitinib and gefitinib affected people with non-small-cell lung cancer (NSCLC) who had mutations in the EGFR gene. In this study, people who were treated with dacomitinib lived longer without their cancer getting worse than people who were treated with gefitinib. Skin adverse reactions were higher in people who were treated with dacomitinib than gefitinib. In this follow-up analysis, researchers wanted to see if the treatment effect of dacomitinib was different between people who had skin adverse reactions and people who did not have skin adverse reactions after treatment with dacomitinib. The results from this analysis showed that after treatment with dacomitinib, half of the people who had skin adverse reactions lived for 16.0 months, and half of the people who did not have skin adverse reactions lived for 9.2 months without their cancer getting worse. This study also showed that half of the people who had skin adverse reactions lived for 37.7 months, and half of the people who did not have skin adverse reactions lived for 21.6 months. In summary, the results from this study showed that the treatment effect of dacomitinib was better in people who had skin adverse reactions after treatment with dacomitinib. Therefore, skin adverse reactions can be a marker of better treatment effect in people with NSCLC who had mutations in the EGFR gene when treated with dacomitinib.

Novel DNA Repair Inhibitors Targeting XPG to Enhance Cisplatin Therapy in Non-Small Cell Lung Cancer: Insights from In Silico and Cell-Based Studies.

NSCLC is marked by low survival and resistance to platinum-based chemotherapy. The XPG endonuclease has emerged as a promising biomarker for predicting the prognosis of cisplatin-treated patients and its downregulation having been reported to increase cisplatin efficacy. This study presents an integrated strategy for identifying small molecule inhibitors of XPG to improve cisplatin therapy in NSCLC. A structure-based virtual screening approach was adopted, including a structural and physicochemical analysis of the protein, and a library of small molecules with reported inhibitory activities was retrieved. This analysis identified Lys84 as a crucial residue for XPG activity by targeting its interaction with DNA. After molecular docking and virtual screening calculations, 61 small molecules were selected as potential XPG inhibitors, acquired from the ChemBridge database and then validated in H1299 cells, a NSCLC cell line exhibiting the highest ERCC5 expression. The MTS assay was performed as a first screening approach to determine whether these potential inhibitors could enhance cisplatin-induced cytotoxicity. Overall, among the eight compounds identified as the most promising, three of them revealed to significantly increase the impact of cisplatin. The inherent cytotoxicity of these compounds was further investigated in a non-tumoral lung cell line (BEAS-2B cells), which resulted in the identification of two non-cytotoxic candidates to be used in combination with cisplatin in order to improve its efficacy in NSCLC therapy.

Impact of the redox-active MnTnHex-2-PyP5+ and cisplatin on the metabolome of non-small cell lung cancer cells.

Redox-based cancer therapeutic strategies aim to raise reactive oxygen species (ROS) levels in cancer cells, thus modifying their redox status, and eventually inducing cell death. Promising compounds, known as superoxide dismutase mimics (SODm), e.g. MnTnHex-2-Py5+ (MnTnHex), could increase intracellular H2O2 in cancer cells with deficient ROS removal systems and therefore enhance radio- and chemotherapy efficacy. We have previously shown that MnTnHex was cytotoxic either alone or combined with cisplatin to non-small cell lung cancer (NSCLC) cells. To gain a deeper understanding of the effects and safety of this compound, it is crucial to analyze the metabolic alterations that take place within the cell. Our goal was thus to study the intracellular metabolome (intracellular metabolites) of NSCLC cells (A549 and H1975) using nuclear magnetic resonance (NMR) spectroscopy-based metabolomics to evaluate the changes in cellular metabolism upon exposure to MnTnHex per se or in combination with cisplatin. 1H NMR metabolomics revealed a higher number of significantly altered metabolites in A549 cells exposed to MnTnHex alone or combined with cisplatin in comparison with non-treated cells (nine dysregulated metabolites), suggesting an impact on aminoacyl-tRNA biosynthesis, glycolysis/gluconeogenesis, taurine, hypotaurine, glycerophospholipid, pyruvate, arginine and proline metabolisms. Regarding H1975 cells, significant alterations in the levels of six metabolites were observed upon co-treatment with MnTnHex and cisplatin, suggesting dysregulations in aminoacyl-tRNA biosynthesis, arginine and proline metabolism, pyruvate metabolism, and glycolysis/gluconeogenesis. These findings help us to understand the impact of MnTnHex on NSCLC cells. Importantly, specific altered metabolites, such as taurine, may contribute to the chemosensitizing effects of MnTnHex.

Deciphering the impact of STAT3 activation mediated by PTPRT promoter hypermethylation as biomarker of response to paclitaxel-plus-cetuximab in patients with recurrent or metastatic squamous cell carcinoma of the head and neck.

BACKGROUND: Squamous cell carcinoma of the head and neck (SCCHN) is an aggressive disease with poor prognosis. It is known that the activation of STAT3 signaling pathways promotes the development and progression of this neoplasia and it has been described the role of PTPRT as a negative regulator of STAT3. Then, we have evaluated the impact of them as biomarkers of outcome in a series of patients with recurrent and/or metastatic SCCHN treated with weekly paclitaxel-plus-cetuximab (ERBITAX) regimen. PATIENTS AND METHODS: Between 2008 and 2017, 52 patients with recurrent/metastatic SCCHN were treated with ERBITAX at our center, 34 of whom had available tumor samples. Phosphorylated STAT3 (pSTAT3) protein expression was analyzed by immunohistochemistry, STAT3 mRNA expression by qPCR, and PTPRT promoter methylation by methylation-specific PCR. Molecular results were correlated with response rate (RR), progression-free survival (PFS), and overall survival (OS). RESULTS: pSTAT3 overexpression was detected in 67% and PTPRT promoter hypermethylation in 41% of tumor samples. PTPRT promoter hypermethylation showed a trend towards an association with lower RR (21% vs. 60%; p = 0.06). A lower RR was also observed in patients with pSTAT3 overexpression (36% vs. 54%) and in those with high STAT3 mRNA levels (43% vs. 64%), but these differences did not reach statistical significance. PTPRT promoter hypermethylation correlated with pSTAT3 overexpression (p = 0.009) but not with STAT3 mRNA overexpression. OS and PFS was shorter in patients with activated STAT3, but the difference did not reach statistical significance. CONCLUSIONS: Although this was a relatively small retrospective study, it provides preliminary indications of the potential role of the STAT3 pathway on outcome in SCCHN and confirms that PTPRT acts as a negative regulator of STAT3. Our findings warrant investigation in a larger patient cohort to determine if inactivating this pathway through specific targeted treatments could improve outcomes in recurrent/metastatic SCCHN patients.

KRAS-mutant non-small cell lung cancer (NSCLC) therapy based on tepotinib and omeprazole combination.

BACKGROUND: KRAS-mutant non-small cell lung cancer (NSCLC) shows a relatively low response rate to chemotherapy, immunotherapy and KRAS-G12C selective inhibitors, leading to short median progression-free survival, and overall survival. The MET receptor tyrosine kinase (c-MET), the cognate receptor of hepatocyte growth factor (HGF), was reported to be overexpressed in KRAS-mutant lung cancer cells leading to tumor-growth in anchorage-independent conditions. METHODS: Cell viability assay and synergy analysis were carried out in native, sotorasib and trametinib-resistant KRAS-mutant NSCLC cell lines. Colony formation assays and Western blot analysis were also performed. RNA isolation from tumors of KRAS-mutant NSCLC patients was performed and KRAS and MET mRNA expression was determined by real-time RT-qPCR. In vivo studies were conducted in NSCLC (NCI-H358) cell-derived tumor xenograft model. RESULTS: Our research has shown promising activity of omeprazole, a V-ATPase-driven proton pump inhibitor with potential anti-cancer properties, in combination with the MET inhibitor tepotinib in KRAS-mutant G12C and non-G12C NSCLC cell lines, as well as in G12C inhibitor (AMG510, sotorasib) and MEK inhibitor (trametinib)-resistant cell lines. Moreover, in a xenograft mouse model, combination of omeprazole plus tepotinib caused tumor growth regression. We observed that the combination of these two drugs downregulates phosphorylation of the glycolytic enzyme enolase 1 (ENO1) and the low-density lipoprotein receptor-related protein (LRP) 5/6 in the H358 KRAS G12C cell line, but not in the H358 sotorasib resistant, indicating that the effect of the combination could be independent of ENO1. In addition, we examined the probability of recurrence-free survival and overall survival in 40 early lung adenocarcinoma patients with KRAS G12C mutation stratified by KRAS and MET mRNA levels. Significant differences were observed in recurrence-free survival according to high levels of KRAS mRNA expression. Hazard ratio (HR) of recurrence-free survival was 7.291 (p = 0.014) for high levels of KRAS mRNA expression and 3.742 (p = 0.052) for high MET mRNA expression. CONCLUSIONS: We posit that the combination of the V-ATPase inhibitor omeprazole plus tepotinib warrants further assessment in KRAS-mutant G12C and non G12C cell lines, including those resistant to the covalent KRAS G12C inhibitors.

Top 20 EGFR+ NSCLC Clinical and Translational Science Papers That Shaped the 20 Years Since the Discovery of Activating EGFR Mutations in NSCLC. An Editor-in-Chief Expert Panel Consensus Survey.

The year 2024 is the 20th anniversary of the discovery of activating epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC). Since then, tremendous advances have been made in the treatment of NSCLC based on this discovery. Some of these studies have led to seismic changes in the concept of oncology research and spurred treatment advances beyond NSCLC, leading to a current true era of precision oncology for all solid tumors. We now routinely molecularly profile all tumor types and even plasma samples of patients with NSCLC for multiple actionable driver mutations, independent of patient clinical characteristics nor is profiling limited to the advanced incurable stage. We are increasingly monitoring treatment responses and detecting resistance to targeted therapy by using plasma genotyping. Furthermore, we are now profiling early-stage NSCLC for appropriate adjuvant targeted treatment leading to an eventual potential "cure" in early-stage EGFR+ NSCLC which have societal implication on implementing lung cancer screening in never-smokers as most EGFR+ NSCLC patients are never-smokers. All these advances were unfathomable in 2004 when the five papers that described "discoveries" of activating EGFR mutations (del19, L858R, exon 20 insertions, and "uncommon" mutations) were published. To commemorate this 20th anniversary, we assembled a global panel of thoracic medical oncology experts to select the top 20 papers (publications or congress presentation) from the 20 years since this seminal discovery with December 31, 2023 as the cutoff date for inclusion of papers to be voted on. Papers ranked 21 to 30 were considered "honorable mention" and also annotated. Our objective is that these 30 papers with their annotations about their impact and even all the ranked papers will serve as "syllabus" for the education of future thoracic oncology trainees. Finally, we mentioned potential practice-changing clinical trials to be reported. One of them, LAURA was published online on June 2, 2024 was not included in the list of papers to be voted on but will surely be highly ranked if this consensus survery is performed again on the 25th anniversay of the discovery EGFR mutations (i.e. top 25 papers on the 25 years since the discovery of activating EGFR mutations).

HMGB1 Expression Levels Correlate with Response to Immunotherapy in Non-Small Cell Lung Cancer.

Purpose: High-mobility group box 1 protein (HMGB1) is subject to exportin 1 (XPO1)-dependent nuclear export, and it is involved in functions implicated in resistance to immunotherapy. We investigated whether HMGB1 mRNA expression was associated with response to immune checkpoint inhibitors (ICI) in non-small cell lung cancer (NSCLC). Patients and Methods: RNA was isolated from pretreatment biopsies of patients with advanced NSCLC treated with ICI. Gene expression analysis of several genes, including HMGB1, was conducted using the NanoString Counter analysis system (PanCancer Immune Profiling Panel). Western blotting analysis and cell viability assays in EGFR and KRAS mutant cell lines were carried out. Evaluation of the antitumoral effect of ICI in combination with XPO1 blocker (selinexor) and trametinib was determined in a murine Lewis lung carcinoma model. Results: HMGB1 mRNA levels in NSCLC patients treated with ICI correlated with progression-free survival (PFS) (median PFS 9.0 versus 18.0 months, P=0.008, hazard ratio=0.30 in high versus low HMGB1). After TNF-α stimulation, HMGB1 accumulates in the cytoplasm of PC9 cells, but this accumulation can be prevented by using selinexor or antiretroviral drugs. Erlotinib or osimertinib with selinexor in EGFR-mutant cells and trametinib plus selinexor in KRAS mutant abolish tumor cell proliferation. Selinexor with a PD-1 inhibitor with or without trametinib abrogates the tumor growth in the murine Lewis lung cancer model. Conclusion: An in-depth exploration of the functions of HMGB1 mRNA and protein is expected to uncover new potential targets and provide a basis for treating metastatic NSCLC in combination with ICI.

PD-1-induced encephalopathy: a report of 2 cases on neurological toxicities with immune checkpoint inhibitors.

Background: Immune-related adverse effects (irAEs) often occur during immune checkpoint inhibitor (ICI) therapy. In the nervous system, the incidence of irAEs ranges from 0.1-12%, with 80% occurring within the first 4 months of ICI application. For complications of the nervous system, adequate diagnosis is made by signs, symptoms, imaging and cerebrospinal fluid. If severe irAEs occur, ICIs should be discontinued and patients should be treated with high-dose glucocorticoids, immunoglobulins, or immunosorbent therapy with systemic support. Patients who develop severe neurologic irAEs have a poorer prognosis. Case Description: In this article, we report 2 cases of encephalopathy induced by anti-programmed cell death protein 1 (PD-1) monoclonal antibodies at the initial diagnoses. Our findings may help clinicians to differentiate between encephalopathy caused by immunotherapy and other neurological disorders. Case 1 was a 24-year-old male patient who had undergone PD-1 immunotherapy to treat olfactory neuroblastoma. After the 6th course of therapy, he began to develop persistent epilepsy, which decreased significantly after high doses of glucocorticoid and immunosorbent therapy were administered. Based on his medical history and laboratory examination results, PD-1-induced encephalopathy was the most likely diagnosis. Case 2 was a 67-year-old female patient who had been treated with PD-1/programmed death ligand-1 therapy for lung adenocarcinoma. She began to have headaches after 1 cycle of treatment, and her cognitive function gradually decreased with the continuation of immunotherapy. Conclusions: These case reports show the difficulty in distinguishing PD-1-induced encephalopathy from other neurological disorders, especially paraneoplastic neurological syndromes. If not treated properly, patients' lives may be endangered. Thus, early identification and early treatment are very important.

Deterministic reprogramming and signaling activation following targeted therapy in non-small cell lung cancer driven by mutations or oncogenic fusions.

INTRODUCTION: Targeted therapy is used to treat lung adenocarcinoma caused by epidermal growth factor receptor (EGFR) mutations in the tyrosine kinase domain and rare subtypes (<5%) of non-small cell lung cancer. These subtypes include fusion oncoproteins like anaplastic lymphoma kinase (ALK), ROS1, rearranged during transfection (RET), and other receptor tyrosine kinases (RTKs). The use of diverse selective oral inhibitors, including those targeting rat sarcoma viral oncogene homolog (KRAS) mutations, has significantly improved clinical responses, extending progression-free and overall survival. AREAS COVERED: Resistance remains a critical issue in lung adenocarcinoma, notably in EGFR mutant, echinoderm microtubule associated protein-like 4 (EML4)-ALK fusion, and KRAS mutant tumors, often associated with epithelial-to-mesenchymal transition (EMT). EXPERT OPINION: Despite advancements in next generation EGFR inhibitors and EML4-ALK therapies with enhanced brain penetrance and identifying resistance mutations, overcoming resistance has not been abated. Various strategies are being explored to overcome this issue to achieve prolonged cancer remission and delay resistance. Targeting yes-associated protein (YAP) and the mechanisms associated with YAP activation through Hippo-dependent or independent pathways, is desirable. Additionally, the exploration of liquid-liquid phase separation in fusion oncoproteins forming condensates in the cytoplasm for oncogenic signaling is a promising field for the development of new treatments.

Converging and evolving immuno-genomic routes toward immune escape in breast cancer.

The interactions between tumor and immune cells along the course of breast cancer progression remain largely unknown. Here, we extensively characterize multiple sequential and parallel multiregion tumor and blood specimens of an index patient and a cohort of metastatic triple-negative breast cancers. We demonstrate that a continuous increase in tumor genomic heterogeneity and distinct molecular clocks correlated with resistance to treatment, eventually allowing tumors to escape from immune control. TCR repertoire loses diversity over time, leading to convergent evolution as breast cancer progresses. Although mixed populations of effector memory and cytotoxic single T cells coexist in the peripheral blood, defects in the antigen presentation machinery coupled with subdued T cell recruitment into metastases are observed, indicating a potent immune avoidance microenvironment not compatible with an effective antitumor response in lethal metastatic disease. Our results demonstrate that the immune responses against cancer are not static, but rather follow dynamic processes that match cancer genomic progression, illustrating the complex nature of tumor and immune cell interactions.

Unveiling Novel ERCC1-XPF Complex Inhibitors: Bridging the Gap from In Silico Exploration to Experimental Design.

Modifications in DNA repair pathways are recognized as prognostic markers and potential therapeutic targets in various cancers, including non-small cell lung cancer (NSCLC). Overexpression of ERCC1 correlates with poorer prognosis and response to platinum-based chemotherapy. As a result, there is a pressing need to discover new inhibitors of the ERCC1-XPF complex that can potentiate the efficacy of cisplatin in NSCLC. In this study, we developed a structure-based virtual screening strategy targeting the inhibition of ERCC1 and XPF interaction. Analysis of crystal structures and a library of small molecules known to act against the complex highlighted the pivotal role of Phe293 (ERCC1) in maintaining complex stability. This residue was chosen as the primary binding site for virtual screening. Using an optimized docking protocol, we screened compounds from various databases, ultimately identifying more than one hundred potential inhibitors. Their capability to amplify cisplatin-induced cytotoxicity was assessed in NSCLC H1299 cells, which exhibited the highest ERCC1 expression of all the cell lines tested. Of these, 22 compounds emerged as promising enhancers of cisplatin efficacy. Our results underscore the value of pinpointing crucial molecular characteristics in the pursuit of novel modulators of the ERCC1-XPF interaction, which could be combined with cisplatin to treat NSCLC more effectively.

Vaccine antibodies against a synthetic epidermal growth factor variant enhance the antitumor effects of inhibitors targeting the MAPK/ERK and PI3K/Akt pathways.

BACKGROUND: The EGFR pathway is involved in intrinsic and acquired resistance to a wide variety of targeted therapies in cancer. Vaccination represents an alternative to the administration of anti-EGFR monoclonal antibodies, such as cetuximab or panitumumab. Here, we tested if anti-EGF antibodies generated by vaccination (anti-EGF VacAbs) could potentiate the activity of drugs targeting the ERK/MAPK and PI3K/Akt pathways. METHODS: Non-small cell lung cancer (NSCLC), colorectal cancer (CRC) and melanoma cell lines harboring KRAS, NRAS, BRAF and PIK3CA mutations were used. Anti-EGF VacAbs were obtained by immunizing rabbits with a fusion protein containing a synthetic, highly mutated variant of human EGF. Cell viability was determined by MTT, total and phosphorylated proteins by Western blotting, cell cycle distribution and cell death by flow cytometry and emergence of resistance by microscopic examination in low density cultures. RESULTS: Anti-EGF VacAbs potentiated the antiproliferative effects of MEK, KRAS G12C, BRAF, PI3K and Akt inhibitors in KRAS, NRAS, BRAF and PIK3CA mutant cells and delayed the appearance of resistant clones in vitro. The effects of anti-EGF VacAbs were comparable or superior to those of panitumumab and cetuximab. The combination of anti-EGF VacAbs with the targeted inhibitors effectively suppressed EGFR downstream pathways and sera from patients immunized with an anti-EGF vaccine also blocked activation of EGFR effectors. CONCLUSIONS: Anti-EGF VacAbs enhance the antiproliferative effects of drugs targeting the ERK/MAPK and PIK3CA/Akt pathways. Our data provide a rationale for clinical trials testing anti-EGF vaccination combined with inhibitors selected according to the patient's genetic profile.

Impact of Concurrent Genomic Alterations on Clinical Outcomes in Patients With ALK-Rearranged NSCLC.

INTRODUCTION: ALK tyrosine kinase inhibitors have exhibited promising activity against advanced ALK-rearranged NSCLC. However, co-occurring genetic alterations, such as CDKN2A/B or TP53, may negatively affect the efficacy of targeted therapies. METHODS: From December 2017 to December 2022, this study cohort analyzed next-generation sequencing data of 116 patients with metastatic ALK-rearranged NSCLC from five Latin American cancer centers. Clinicopathologic and molecular features were associated with clinical outcomes and risk of brain metastasis (BrM) in patients with and without concurrent somatic alterations. RESULTS: All patients (N = 116) received a second-generation ALK tyrosine kinase inhibitor, and alectinib was selected in 87.2% of cases. Coalterations occurred in 62% of the cases; the most frequent were TP53 mutations (27%) and CDKN2A/B loss (18%). The loss of CDKN2A/B was associated with an increased risk of BrM, with a cumulative incidence of 33.3% versus 7.4% in the non-coaltered subgroup. Compared with patients without coalterations, patients with concurrent CDKN2A/B loss (n = 21) had a shorter median progression-free survival (10.2 versus 34.2 mo, p < 0.001) and overall survival (26.2 versus 80.7 mo, p < 0.001). In the multivariate analysis, co-occurring CDKN2A/B loss was associated with poorer progression-free survival and OS despite the presence of other somatic coalterations, TP53 mutations, BrM, and Eastern Cooperative Oncology Group Performance Status. CONCLUSIONS: This study confirmed the worse prognostic value, which depicted co-occurring alterations in patients with ALK rearrangement. CDKN2A/B loss was substantially associated with worse outcomes and a higher risk of brain metastases. The evidence presented in our study may help select patients with ALK-positive tumors suitable for treatment escalation and closer brain follow-up.

KRAS G12C-mutant driven non-small cell lung cancer (NSCLC).

KRAS G12C mutations in non-small cell lung cancer (NSCLC) partially respond to KRAS G12C covalent inhibitors. However, early adaptive resistance occurs due to rewiring of signaling pathways, activating receptor tyrosine kinases, primarily EGFR, but also MET and ligands. Evidence indicates that treatment with KRAS G12C inhibitors (sotorasib) triggers the MRAS:SHOC2:PP1C trimeric complex. Activation of MRAS occurs from alterations in the Scribble and Hippo-dependent pathways, leading to YAP activation. Other mechanisms that involve STAT3 signaling are intertwined with the activation of MRAS. The high-resolution MRAS:SHOC2:PP1C crystallization structure allows in silico analysis for drug development. Activation of MRAS:SHOC2:PP1C is primarily Scribble-driven and downregulated by HUWE1. The reactivation of the MRAS complex is carried out by valosin containing protein (VCP). Exploring these pathways as therapeutic targets and their impact on different chemotherapeutic agents (carboplatin, paclitaxel) is crucial. Comutations in STK11/LKB1 often co-occur with KRAS G12C, jeopardizing the effect of immune checkpoint (anti-PD1/PDL1) inhibitors.

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.