A Phase II trial of alternating osimertinib and gefitinib therapy in advanced EGFR-T790M positive non-small cell lung cancer: OSCILLATE.

In this phase II, single arm trial (ACTRN12617000720314), we investigate if alternating osimertinib and gefitinib would delay the development of resistance to osimertinib in advanced, non-small cell lung cancer (NSCLC) with the epidermal growth factor receptor (EGFR) T790M mutation (n = 47) by modulating selective pressure on resistant clones. The primary endpoint is progression free-survival (PFS) rate at 12 months, and secondary endpoints include: feasibility of alternating therapy, overall response rate (ORR), overall survival (OS), and safety. The 12-month PFS rate is 38% (95% CI 27.5-55), not meeting the pre-specified primary endpoint. Serial circulating tumor DNA (ctDNA) analysis reveals decrease and clearance of the original activating EGFR and EGFR-T790M mutations which are prognostic of clinical outcomes. In 73% of participants, loss of T790M ctDNA is observed at progression and no participants have evidence of the EGFR C797S resistance mutation following the alternating regimen. These findings highlight the challenges of treatment strategies designed to modulate clonal evolution and the clinical importance of resistance mechanisms beyond suppression of selected genetic mutations in driving therapeutic escape to highly potent targeted therapies.

Lurbinectedin in small cell lung cancer: real-world experience of a multicentre national early access programme.

BACKGROUND AND AIMS: Lurbinectedin is a novel oncogenic transcription inhibitor active in several cancers, including small cell lung cancer (SCLC). We aimed to describe the first Australian experience of the clinical efficacy and tolerability of lurbinectedin for the treatment of SCLC after progression on platinum-containing therapy. METHODS: Multicentre real-world study of individuals with SCLC initiating lurbinectedin monotherapy (3.2 mg/m2 three-weekly) on an early access programme between May 2020 and December 2021. Key outcomes were clinical utilisation, efficacy and tolerability. Progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan-Meier method. Outcome data were collected within the AUstralian Registry and biObank of thoRacic cAncers (AURORA). RESULTS: Data were analysed for 46 individuals across seven sites. Lurbinectedin was given as second- (83%, 38/46) or subsequent- (17%, 8/46) line therapy, mostly with prior chemoimmunotherapy (87%, 40/46). We report dose modifications (17%, 8/46), interruptions/delays (24%, 11/46), high-grade toxicities (28%, 13/46) and hospitalisations (54%, 25/46) during active treatment. The overall response rate was 33% and the disease control rate was 50%. Six-month OS was 44% (95% confidence interval (CI): 29.0-57.1). Twelve-month OS was 15% (95% CI: 6.5-26.8). From lurbinectedin first dose, the median PFS was 2.5 months (95% CI: 1.8-2.9) and OS was 4.5 months (95% CI: 3.5-7.2). From SCLC diagnosis, the median OS was 12.9 months (95% CI: 11.0-17.2). Individuals with a longer chemotherapy-free interval prior to lurbinectedin had longer PFS and OS. CONCLUSION: This real-world national experience of lurbinectedin post-platinum chemotherapy and immunotherapy for individuals with SCLC was similar to that reported in clinical trials.

Implementation of a nurse-led, multidisciplinary model of care for older adults with cancer: a process evaluation protocol.

INTRODUCTION: Cancer is predominantly a disease of older adults, with an increasing number of cancer diagnoses in individuals aged 65 or older. Multiple geriatric factors have been shown to impact patient outcomes in cancer treatment. However, oncology specialists are not well adapted to incorporate geriatric assessment into practice due to a lack of resources and knowledge of the specialty.The primary aim of this study is to implement and evaluate a nurse-led, multidisciplinary model of care for older adults with cancer at two public tertiary hospitals in Melbourne, Australia. METHODS AND ANALYSIS: This study will aim to assess 200 patients across 2 sites. Both sites will assess individuals with lung cancer; the second site will also include individuals with genitourinary, upper gastrointestinal and colorectal cancers.This process evaluation will use quantitative and qualitative methods to explore the reach, effectiveness, adoption, implementation, and maintenance (RE-AIM) of the nurse-led, multidisciplinary model of care. ETHICS AND DISSEMINATION: Ethical approval and local governance approvals have been obtained by Austin Health and Monash Health Human Research Ethics committees. Dissemination will occur via publications, conferences, social medical and local engagement with clinicians, consumers and managers.

Antibody drug conjugates for glioblastoma: current progress towards clinical use.

INTRODUCTION: Antibody drug conjugates (ADCs) are now a proven therapeutic class for many cancers, combining highly specific targeting with the potency of high effective payloads. This review summarizes the experience with ADCs in brain tumors and examines future paths for their use in these tumors. AREAS COVERED: This review will cover all the key classes of ADCs which have been tested in primary brain tumors, including commentary on the major trials to date. The efficacy of these trials, as well as their limitations, will put in context of the overall landscape of drug development in brain tumors. Importantly, this review will summarize key learnings and insights from these trials that help provide the basis for rational ways in which these drugs can be effectively and appropriate developed for patients with primary brain tumors. EXPERT OPINION: ADC development in brain tumors has occurred in two major phases to date. Key learnings from previous trials provide a strong rationale for the continued development of these drugs for primary brain tumors. However, the unique biology of these tumors requires development strategies specifically tailored to maximize their optimal development.

Real-world challenges in undertaking NTRK fusion testing in non-small cell lung cancer.

Background: We performed a retrospective analysis to determine the incidence of neurotrophic tropomyosin-receptor kinase (NTRK) fusion in non-small cell lung cancer (NSCLC). Methods: Archival NSCLC tissues between 2018-2020 were screened by immunohistochemistry (IHC) with IHC-positive cases undergoing confirmatory molecular analysis. Correlative clinicopathologic parameters were collected. Results: Of 289 samples analyzed, 10 (3.5%) cases had NTRK expression on IHC. The median age of patients with NTRK-positivity on IHC was 74.9 (range, 44-88) years and 70% had a smoking history. The cohort included seven adenocarcinomas and one each squamous cell carcinoma, large-cell neuroendocrine and not otherwise specified histologies. PDL1 expression was ≤50% in five cases. Concurrent EGFR mutations were detected in three cases, with two cases also showing a PIK3CA E542K mutation and MET amplification, respectively. Due to insufficient tumor material, RNA-sequencing was undertaken in only one IHC-positive case, with the other nine cases analyzed by Fluorescent in-situ Hybridisation. A NTRK fusion, EML4-NTRK3 gene fusion was detected in one patient, a frequency of 0.35%. Conclusions: NTRK fusions in NSCLC are rare. This study highlights real world diagnostic challenges regarding NTRK testing, such as requirements of adequate tumor tissue and appropriate testing methodologies.

Real-World Analysis of Clinical Characteristics and Survival Outcomes in Patients With Extensive-Stage SCLC Treated With First-Line Chemoimmunotherapy.

Introduction: There are no clinically validated prognostic biomarkers in the management of extensive-stage SCLC (ES-SCLC). We explored the association between clinical characteristics and survival outcomes in patients with ES-SCLC treated with chemoimmunotherapy. Methods: In this retrospective cohort study, patients with ES-SCLC treated with first-line platinum-etoposide chemotherapy and atezolizumab were identified from medical records. Pretreatment clinical characteristics, biochemical parameters, and tumor and treatment characteristics were collected. Univariate and multivariate Cox regression were used to evaluate treatment effect on progression-free survival (PFS) and overall survival (OS). Results: We evaluated 75 patients in total. The median PFS and OS were 6.1 months and 9.2 months, respectively. Statistically significant associations were found with lower lactate dehydrogenase and improved OS (hazard ratio [HR] = 1.0, 95% confidence interval [CI]: 1.0-1.01, p = 0.006), whereas higher age (HR = 0.94, 95% CI: 0.90-0.98, p = 0.006) and lower neutrophil-to-lymphocyte ratio (HR = 1.08, 95% CI: 1.02-1.14, p = 0.005) were associated with improved PFS. The number of chemotherapy cycles received were associated with both an improved PFS (HR = 0.57, 95% CI: 0.37-0.89, p = 0.011) and OS (HR = 0.5, 95% CI: 0.30-0.84, p = 0.008). Conclusions: This study highlights the important effect of chemotherapy on survival. Furthermore, the association between lactate dehydrogenase and neutrophil-to-lymphocyte ratio on survival further suggests that baseline tumor burden and optimizing sarcopenia are important factors for clinicians to consider as we seek to develop personalized treatment for this disease.

LOREALAUS: LOrlatinib REAL-World AUStralian Experience in Advanced ALK-Rearranged NSCLC.

Introduction: Over the past decade, ALK tyrosine kinase inhibitors have delivered unprecedented survival for individuals with ALK-positive (ALK+) lung cancers. Real-world data enhance the understanding of optimal drug sequencing and expectations for survival. Methods: Multicenter real-world study of individuals with pretreated advanced ALK+ lung cancers managed on a lorlatinib access program between 2016 and 2020. Key outcomes were lorlatinib efficacy, tolerability, and treatment sequencing. Progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan-Meier method among all individuals (PFSa and OSa), with at least 30 days (one-cycle) lorlatinib exposure (PFSb and OSb), and with good performance status (PFSc and OSc). Subgroups of interest were analyzed to assess signals of potential clinical applicability. Two OS index dates were analyzed, from lorlatinib initiation and advanced ALK+ diagnosis. Results: The population (N = 38, 10 sites) was heavily pretreated (23 had ≥2 previous treatment lines) with a high disease burden (26 had 2-4 sites and 11 had >4 sites of metastatic disease, 19 had brain metastases). The overall response rate was 44% and the disease control rate was 81%. Lorlatinib dose reduction (18%), interruption (16%), and discontinuation (3%) were consistent with the trial experience. From advanced ALK+ diagnosis, the median OS for populations a, b, and c was 45.0 months, 69.9 months and 61.2 months respectively. From lorlatinib initiation, the median PFSa, PFSb and PFSc was 7.3 months, 13.2 months and 27.7 months and the median OSa, OSb and OSc was 19.9 months, 25.1 months and 27.7 months. The median PFSa with versus without brain metastases was 34.6 months versus 5.8 months (p = 0.09). The intracranial median PFS was 14.2 months. Previous good response versus poor response to the first ALK-directed therapy median PFSa was 27.7 months versus 4.7 months with a hazard ratio of 0.3 (p = 0.01). Conclusions: Lorlatinib is a potent, highly active brain-penetrant third-generation ALK tyrosine kinase inhibitors with benefits for most individuals in the later-line setting in a real-world evaluation, consistent with clinical trial data.

ImmunoPET: IMaging of cancer imMUNOtherapy targets with positron Emission Tomography: a phase 0/1 study characterising PD-L1 with 89Zr-durvalumab (MEDI4736) PET/CT in stage III NSCLC patients receiving chemoradiation study protocol.

BACKGROUND: ImmunoPET is a multicentre, single arm, phase 0-1 study that aims to establish if 89Zr-durvalumab PET/CT can be used to interrogate the expression of PD-L1 in larger, multicentre clinical trials. METHODS: The phase 0 study recruited 5 PD-L1+ patients with metastatic non-small cell lung cancer (NSCLC). Patients received 60MBq/70 kg 89Zr-durva up to a maximum of 74 MBq, with scan acquisition at days 0, 1, 3 or 5±1 day. Data on (1) Percentage of injected 89Zr-durva dose found in organs of interest (2) Absorbed organ doses (µSv/MBq of administered 89Zr-durva) and (3) whole-body dose expressed as mSv/100MBq of administered dose was collected to characterise biodistribution.The phase 1 study will recruit 20 patients undergoing concurrent chemoradiotherapy for stage III NSCLC. Patients will have 89Zr-durva and FDG-PET/CT before, during and after chemoradiation. In order to establish the feasibility of 89Zr-durva PET/CT for larger multicentre trials, we will collect both imaging and toxicity data. Feasibility will be deemed to have been met if more than 80% of patients are able complete all trial requirements with no significant toxicity. ETHICS AND DISSEMINATION: This phase 0 study has ethics approval (HREC/65450/PMCC 20/100) and is registered on the Australian Clinical Trials Network (ACTRN12621000171819). The protocol, technical and clinical data will be disseminated by conference presentations and publications. Any modifications to the protocol will be formally documented by administrative letters and must be submitted to the approving HREC for review and approval. TRIAL REGISTRATION NUMBER: Australian Clinical Trials Network ACTRN12621000171819.

Antibody-drug conjugates: beyond current approvals and potential future strategies.

The recent approvals for antibody-drug conjugates (ADCs) in multiple malignancies in recent years have fuelled the ongoing development of this class of drugs. These novel agents combine the benefits of high specific targeting of oncogenic cell surface antigens with the additional cell kill from high potency cytotoxic payloads, thus achieving wider therapeutic windows. This review will summarise the clinical activity of ADCs in tumour types not covered elsewhere in this issue, such as gastrointestinal (GI) and genitourinary (GU) cancers and glioblastoma (GBM). In addition to the ongoing clinical testing of existing ADCs, there is substantial preclinical and early phase testing of newer ADCs or ADC incorporating strategies. This review will provide selected insights into such future development, focusing on the development of novel ADCs against new antigen targets in the tumour microenvironment (TME) and combination of ADCs with immuno-oncology (IO) agents.

A Multi-Center Real-World Experience of IMpower150 in Oncogene Driven Tumors and CNS Metastases.

BACKGROUND: There are limited real world data on the IMpower150 regimen in oncogene driven tumors and central nervous system metastases; this study aims to address this gap. MATERIALS AND METHODS: Retrospective analysis of patients with advanced non-small cell lung cancer treated with the IMpower150 regimen across 12 Australian sites between July 2018 and April 2021. Clinicopathologic and treatment parameters were correlated with efficacy and toxicity. RESULTS: A total of 106 patients identified with median follow up of 8 months (range 0-72). Median age was 61 years (range 33-83), 34% Asian and 58% never-smokers. An oncogene was reported in 94 (89%) patients, EGFR in 72 (68%). At treatment commencement, 50 (47%) patients had brain metastases, 21 (20%) leptomeningeal disease (LMD) and 47 (44%) liver metastases. 27% were treatment-naïve and pemetrexed was substituted for paclitaxel in 44 (42%). The overall response rate was 51% for all patients; 52% in patients with EGFR mutations. Patients with untreated brain metastases prior to commencing IMpower150 had a similar intracranial response as those with treated brain metastases (55% vs. 53%). The median time to treatment failure and overall survival from commencement of IMpower150 was 5.7 and 11.4 months respectively for the entire cohort and 5.2 and 10.5 months in those with an EGFR sensitizing mutation. Overall survival in patients with liver, brain metastases and LMD was 11.0, 11.4, and 7.1 months respectively. No new safety signals seen. CONCLUSION: In this largely oncogene positive, pre-treated population the IMpower150 regimen demonstrated clinically-meaningful responses, including in patients with CNS disease.

Poor correlation between preclinical and patient efficacy data for tumor targeted monotherapies in glioblastoma: the results of a systematic review.

PURPOSE: Limited progress has been made in treating glioblastoma, and we hypothesise that poor concordance between preclinical and clinical efficacy in this disease is a major barrier to drug development. We undertook a systematic review to quantify this issue. METHODS: We identified phase I trials (P1Ts) of tumor targeted drugs, subsequent trial results and preceding relevant preclinical data published in adult glioblastoma patients between 2006-2019 via structured searches of EMBASE/MEDLINE/PUBMED. Detailed clinical/preclinical information was extracted. Associations between preclinical and clinical efficacy metrics were determined using appropriate non-parametric statistical tests. RESULTS: A total of 28 eligible P1Ts were identified, with median ORR of 2.9% (range 0.0-33.3%). Twenty-three (82%) had published relevant preclinical data available. Five (18%) had relevant later phase clinical trial data available. There was overall poor correlation between preclinical and clinical efficacy metrics on univariate testing. However, drugs that had undergone in vivo testing had significantly longer median overall survival (7.9 vs 5.6mo, p = 0.02). Additionally, drugs tested in ≥ 2 biologically-distinct in vivo models ('multiple models') had a significantly better median response rate than those tested using only one ('single model') or those lacking in vivo data (6.8% vs 1.2% vs. 0.0% respectively, p = 0.027). CONCLUSION: Currently used preclinical models poorly predict subsequent activity in P1Ts, and generally over-estimate the anti-tumor activity of these drugs. This underscores the need for better preclinical models to aid the development of novel anti-glioblastoma drugs. Until these become widely available and used, the use of multiple biologically-distinct in vivo models should be strongly encouraged.

Adult medulloblastoma in an Australian population.

Medulloblastoma in adult patients is a rare condition with limited contemporary demographic and treatment outcome data available in an Australian population. We conducted a retrospective review of patterns of care and outcomes of adult patients diagnosed with medulloblastoma treated at major neuro-oncology centres across Australia between January 2010 and December 2019. A total of 80 patients were identified and the median follow-up after diagnosis was 59.2 (range 0.5-204) months. A variety of chemotherapy regimens were used in the adjuvant and recurrent settings. The median overall survival (mOS) was 78 months (IQR 17.5-94.8). Patients who had no residual disease post-resection or with SHH-subtype tumours had a numerically longer 5-year survival rate than those with residual disease post resection or non-SHH subtypes respectively. The median time to recurrence from diagnosis was 18.4 months. The median OS from 1st relapse was 22.1 months (95% CI 11.7-31.4) and mOS from second relapse was 10.2 months (95% CI 6.6 - NR). This is the largest dataset examining patterns of care of adult patients with medulloblastoma in an Australian population. Substantial variation existed in the chemotherapy agents used in the adjuvant and recurrent setting. As has been demonstrated in a paediatric population, trials such as the upcoming EORTC 1634-BTG/NOA-23 trial (PersoMed-1 study) which are tailoring treatments to molecular profiles are likely to improve outcome in adult medulloblastoma.

A phase 1 safety and bioimaging trial of antibody DS-8895a against EphA2 in patients with advanced or metastatic EphA2 positive cancers.

Ephrin type-A 2 (EphA2) is a transmembrane receptor expressed in epithelial cancers. We report on a phase I dose escalation and biodistribution study of DS-8895a, an anti-EphA2 antibody, in patients with advanced EphA2 positive cancers. DS-8895a was administered at 1, 3, 10 or 20 mg/kg every 2 weeks to determine safety, pharmacokinetics and anti-tumor efficacy. All patients underwent 89Zr trace-labelled infusion of DS-8895a (89Zr-DS-8995a) positron emission tomography imaging to determine the biodistribution of DS-8895a, and correlate findings with EphA2 expression, receptor saturation and response. Nine patients were enrolled on study. Of patients enrolled, seven patients received at least one infusion of DS-8895a: four patients received 1 mg/kg dose (Cohort 1) and three patients received 3 mg/kg dose (Cohort 2). Median age was 67.0 years (range 52-81), majority male (71%), and median number of prior systemic therapies was three (range 0-8). The primary cancer diagnosis was colorectal cancer (two patients) and one patient each had gastric, head and neck, high-grade serous adenocarcinoma, lung, and pancreatic cancers. No dose-limiting toxicities or treatment-related adverse events reported. The best response for the patients in Cohort 1 was stable disease and in Cohort 2 was progressive disease. 89Zr-DS-8895a demonstrated no normal tissue uptake and specific low-grade uptake in most tumours. DS-8895a had limited therapeutic efficacy at doses evaluated and 89Zr-DS-8895a demonstrated low tumour uptake. The biodistribution data from this study were key in halting further development of DS-8895a, highlighting the importance of biodistribution studies in drug development. (Trial registration: ClinicalTrials.gov Identifier NCT02252211).

Radiolabeled Antibodies for Cancer Imaging and Therapy.

Radioimmunoconjugates consist of a monoclonal antibody (mAb) linked to a radionuclide. Radioimmunoconjugates as theranostics tools have been in development with success, particularly in hematological malignancies, leading to approval by the US Food and Drug Administration (FDA) for the treatment of non-Hodgkin's lymphoma. Radioimmunotherapy (RIT) allows for reduced toxicity compared to conventional radiation therapy and enhances the efficacy of mAbs. In addition, using radiolabeled mAbs with imaging methods provides critical information on the pharmacokinetics and pharmacodynamics of therapeutic agents with direct relevance to the optimization of the dose and dosing schedule, real-time antigen quantitation, antigen heterogeneity, and dynamic antigen changes. All of these parameters are critical in predicting treatment responses and identifying patients who are most likely to benefit from treatment. Historically, RITs have been less effective in solid tumors; however, several strategies are being investigated to improve their therapeutic index, including targeting patients with minimal disease burden; using pre-targeting strategies, newer radionuclides, and improved labeling techniques; and using combined modalities and locoregional application. This review provides an overview of the radiolabeled intact antibodies currently in clinical use and those in development.

The systemic management of central nervous system metastases and leptomeningeal disease from advanced lung, melanoma, and breast cancer with molecular drivers: An Australian perspective.

The advent of systemic therapies with high intracranial efficacy in recent years is changing the therapeutic paradigm and renewing interest in the management of central nervous system (CNS) and leptomeningeal metastases from solid organ tumors. CNS metastases have traditionally heralded a dismal prognosis with median survival of 3-10 months, and were primarily treated with local therapeutic modalities, such as surgery or radiation therapy. Although these modalities still have a role in the management of CNS disease, newer agents, such as small molecule tyrosine kinase inhibitors and immune-checkpoint inhibitors, are now paving the way as an alternative therapeutic option for those with oligometastatic or low-volume intracranial disease, potentially eliminating or delaying the need for local treatment modalities in this setting. Herein, we summarize the systemic treatments with proven intracranial efficacy, currently approved for use in Australia for advanced mutation-driven non-small cell lung cancer, melanoma, and breast cancer, as well as novel agents in preclinical and clinical trial development.