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TPS271
Background: Pan added to combination chemotherapy is established first-line therapy for RAS and BRAF wild type mCRC. Elderly patients are not well represented in clinical trials ...and may be more suited to treatment protocols with lower toxicity risks; FU plus bevacizumab (bev) is commonly used. Treatment related efficacy, toxicity, impact on quality of life and other outcomes of pan based regimens in an elderly population have not been well studied. Methods: A prospective non-comparative randomized phase 2 study. Australian Clinical Trials Registry Number: ACTRN 12618000233224. Main inclusion criteria include: Untreated patients aged 70 years or older; RAS and BRAF wild type; ECOG performance 0-2. Randomisation 1:1, stratified by primary tumour side, performance status, number of metastatic sites; to pan 6mg/kg 2 weekly or panitumumab plus FU 400 mg/m² bolus; leucovorin 200mg/m²; FU 2400mg/m² 48 hour infusion 2 weekly. Primary endpoint is 6-month progression-free survival (PFS). Sample size is 80 patients based on expected 6-month PFS rate of 73% with FU and bev. Using the method of Metha-Cain, if 24 or more patients are progression free at 6 months, the one sided 95% confidence interval includes 73% and we declare similar activity. Secondary endpoints include overall survival; toxicity and overall treatment utility, a composite measure of treatment benefit based on radiology, clinical progress, toxicity and patient reflection of the impact of treatment on their daily lives. Patients undergo a comprehensive health assessment at baseline and limited health assessment at 4 months. Physical activity trackers are worn for 2 weeks at treatment commencement and again at week 16. Tumour tissue and blood samples (at baseline, cycle 3 day 1 and at 24 weeks) will be collected for translational research. First site opened in June 2018. Twelve patients have been recruited to date from 9 sites in Australasia. Eighteen sites were open as at September 2019. Clinical trial information: 12618000233224.
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TPS8586
Background: Standard first line treatment for unresectable malignant pleural mesothelioma (MPM) is platinum-based chemotherapy with pemetrexed. Two recent, single-arm, phase 2 ...trials (DREAM1 and PrE05052) combining the PD-L1 inhibitor durvalumab and standard first line cisplatin and pemetrexed (CP) exceeded pre-specified criteria for proceeding to phase 3. DREAM3R aims to determine the effectiveness of adding durvalumab to first line CP chemotherapy in advanced MPM. Methods: Treatment-naïve patients with advanced MPM will be randomised (2:1) to EITHER durvalumab 1500 mg every 3 weeks plus doublet chemotherapy (cisplatin 75 mg/m2 and pemetrexed 500 mg/m2) every 3 weeks for 4-6 cycles, followed by durvalumab 1500 mg every 4 weeks until disease progression, unacceptable toxicity or patient withdrawal; OR doublet chemotherapy alone for 4-6 cycles, followed by observation. The target sample size is 480 patients (320 durvalumab, 160 control) recruited over 27 months, with follow up for an additional 24 months. This provides over 85% power if the true hazard ratio for overall survival is 0.70, with 2-sided alpha of 0.05, assuming a median survival of 15 months in the control group. Key inclusion criteria: MPM of any histological subtype; measurable disease as per RECIST 1.1 modified for mesothelioma (mRECIST 1.1) without prior radiotherapy to these sites; ECOG PS 0-1; and, adequate hematologic, renal, and liver function tests. Key exclusion criteria: prior systemic anticancer treatment for MPM; diagnosis based only on cytology or fine needle aspiration biopsy; contraindication to immunotherapy; and conditions requiring immunosuppressives or corticosteroids. Stratification: Age (18-70 years vs. > 70), sex, histology (epithelioid vs. non-epithelioid), and region (USA vs. ANZ). The primary endpoint is overall survival. Secondary endpoints include progression-free survival; objective tumour response (by mRECIST 1.1 and iRECIST); adverse events; health-related quality of life; and healthcare resource use. Tertiary correlative objectives are to explore and validate potential prognostic and/or predictive biomarkers (including features identified in the DREAM and PrE0505 studies, PD-L1 expression, tumour mutation burden, nuanced genomic characteristics, and HLA subtypes) in tissue and serial blood samples. An imaging databank will be assembled for validation of radiological measures of response, and studies of possible radiomic biomarkers in mesothelioma. Clinical trial information: NCT04334759. and ACTRN 12620001199909.
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5584
Background: Activity of durvalumab in patients with deficient mismatch repair (dMMR) advanced endometrial carcinoma (EC) was confirmed in the PHAEDRA trial (ANZGOG 1601). This ...study investigated the association between immune biomarkers and clinical outcomes in PHAEDRA. Methods: Formalin-fixed paraffin embedded sections immunohistochemically stained for PD-L1 using the Ventana platform, were with matched H&E slides scored independently by two pathologists according to the Ventana PD-L1 (SP263) algorithm for urothelial carcinoma (UC). Immune biomarkers assessed were PD-L1 staining of tumor cells (TCP) and immune cells (IC), and presence of tumor-associated immune cells (ICP). Results: Sixty-seven of the 71 patients had sufficient tumor for PD-L1 testing. AUC were 0.667, 0.726 and 0.644 for TCP, ICP and IC, respectively for predicting tumor response. Optimal cutpoints were TCP≥1%, ICP≥10% and IC≥35%. ICP≥10% achieved the highest sensitivity (53%) and specificity (82%) of the individual cutpoints. The optimal cutpoint algorithm was able to identify patients who would not respond, (sensitivity 88%, negative predictive value 92%), but had low specificity (48%) and positive predictive value (37%). Differences in PFS were found using ICP≥10% (logrank p = 0.01), compared to TCP (p = 0.25), IC (p = 0.48) and the UC algorithm (p = 0.08) (Figure 1). PFS was shorter in patients with pMMR than dMMR after adjusting for ICP (HR 2.99, 95%CI: 1.61-5.57, p < 0.001). Adjustment for MMR reduced the prognostic significance of ICP≥10% for PFS (HR 0.59, 95% CI: 0.28-1.23, p = 0.16). For OS, differences were seen for the UC algorithm (p = 0.02), but not ICP (p = 0.07), TCP (p = 0.18) or IC (p = 0.23). Similarly to PFS, adjustment for MMR reduced the prognostic significance of the UC algorithm for OS (HR: 0.53, 95% CI: 0.25-1.12, p = 0.10). Conclusions: In this exploratory analysis, ICP was more closely associated with tumor response and PFS than TCP or IC. ICP alone was better than the UC algorithm for predicting PFS. The optimum cutpoint algorithm was promising for identifying non-responders, but requires external validation. Clinical trial information: ACTRN12617000106336.
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TPS4172
Background: Eighty per cent of patients with non-metastatic pancreatic cancer have high-risk, borderline resectable (BRPC) or locally advanced pancreas cancer (LAPC), conferring ...a 5-year overall survival of only 12%. MASTERPLAN evaluates the safety and activity of stereotactic body radiotherapy (SBRT) added to neoadjuvant chemotherapy in these patient cohorts. Methods: MASTERPLAN is an investigator-initiated prospective multi-centre randomized phase II trial. Inclusion criteria include histologically confirmed high-risk, BRPC or LAPC. High risk is defined as tumour > 4cm, extrapancreatic extension or node positive. Randomisation is 2:1 to chemotherapy + SBRT (investigational arm) or chemotherapy (control arm) by minimisation with stratification by operability (potentially operable - high risk; BRPC versus inoperable – LAPC; medically inoperable), planned chemotherapy and institution. Both treatment arms receive 6 x 2 weekly cycles of modified FOLFIRINOX (mFOLFIRINOX). Gemcitabine and nab-paclitaxel is permitted if mFOLFIRINOX is unsuitable. The investigational arm receives SBRT (40Gy in 5 fractions) with real time quality assurance. Resectability will be evaluated following initial chemotherapy +/- SBRT. Adjuvant chemotherapy is 6 cycles (12 weeks) of mFOLFIRINOX, or the same duration of gemcitabine and capecitabine (GEMCAP) if neoadjuvant gemcitabine/ nab-paclitaxel given. SBRT adverse events (AEs) will be recorded until study cessation. The primary endpoint is 12-month locoregional control. Secondary endpoints: safety, surgical morbidity and mortality, radiological response rate, progression free survival, pathological response rate, surgical resection rate, R0 resection rate, quality of life, deterioration free survival and overall survival. Biospecimens are collected for translational research for potential prognostic/predictive biomarkers of clinical endpoints and include serial tumour tissue collection from patients undergoing fiducial marker insertion and/or surgery, biopsy at disease progression, serial blood collection and serial buccal and faecal sample collection. An interim analysis will review locoregional failure, distant metastasis and rate of death on the first 40 patients after completion of 12 months follow up. The sample size is 120 patients (80 intervention:40 control), balanced for BRPC/LAPC (60 in each cohort). The minimum follow up is 12 months. The first site opened in October 2019 and 10 patients have been recruited from five sites at 17 Feb 2021. Overall 15 sites in Australia and New Zealand are planned to open to recruitment. Australian Clinical Trials Registry Number: ACTRN12619000409178. Clinical trial information: ACTRN12619000409178.
Abstract
BACKGROUND
Nivolumab is a PD-1 inhibitor with known safety profile. An increase in mutations as we age is well documented in glioblastoma and other cancers. Higher mutational load is ...associated with increased response to nivolumab in extracranial malignancies. NUTMEG examined the activity of nivolumab added to temozolomide in glioblastoma patients aged ≥ 65 years.
METHODS
NUTMEG was an international multicenter phase II trial for newly diagnosed glioblastoma patients aged ≥ 65 years, randomized 2:1 to experimental (40Gy/15 fractions with temozolomide 75mg/m2, then 6 cycles of temozolomide 150-200mg/m2 D1-5 Q28D + nivolumab 240mg D1,15 Q28D C1-4 and 480mg D1 Q28D C5-6) versus standard arm (40Gy/15 fractions with temozolomide 75mg/m2, then 6 cycles of temozolomide alone 150-200mg/m2 D1-5 Q28D), stratified by age, ECOG status, MGMT status and resection extent.
RESULTS
103 patients were enrolled (69 in experimental arm, 34 in standard arm). Median age was 73 years, 36% ECOG 0, 57% MGMT-unmethylated and 51% gross macroscopic resection. Median follow-up is 31 months to date, with 77 deaths (surviving patients to continue follow-up and final results will be presented). Median overall survival was 11.8 months in the experimental arm versus 12.0 months in the standard arm (HR 0.95 95%CI 0.59-1.53 for experimental relative to control). Six-month progression-free survival rate using mRANO was 64% in the experimental arm versus 49% in the standard arm (HR 0.81 95%CI 0.51-1.26). Grade 3/4 adverse events were reported in 46% of experimental arm (7% lung infection, 7% thromboembolic events, 6% fatigue, 6% muscle weakness) and in 29% of control arm (9% fatigue, 6% seizure, 6% thromboembolic events).
CONCLUSIONS
There was insufficient evidence of clinical benefit with nivolumab in this population. No new safety signals were identified. Central imaging review is underway and correlative studies will characterize the immune landscape, including mutational load, neoantigen and other immune markers. NCT04195139.
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TPS9097
Background: Recent data has demonstrated improvements in overall survival in patients with advanced non-small cell lung cancer (NSCLC) treated with nivolumab. Radiation may ...augment the immune response through abscopal effects - evidence of tumour control at sites other than those irradiated. We hypothesize that the addition of stereotactic ablative body radiotherapy (SABR) to immunotherapy with nivolumab will improve progression free survival (PFS) compared with nivolumab alone. Methods: DESIGN: Open label, randomised phase II trial with 25 sites across Australia and New Zealand. ELIGIBILITY: Metastatic NSCLC progressing after 1 or 2 lines of chemotherapy with an extrapulmonary metastasis suitable for SABR. STRATIFICATION: Age, lines of chemotherapy, histology and treating institution. TREATMENT: A single dose of SABR (18-20Gy) plus nivolumab or nivolumab alone (240mg 2-weekly) given until disease progression or prohibitive adverse events. ENDPOINTS: PFS at 6 months (PFS6; primary), objective tumour response rate, adverse events, overall survival, PFS at 1 and 2 years. Tertiary correlative objectives include associations between possible prognostic/ predictive biomarkers and outcomes (including PD-L1 expression). STATISTICS:Total sample size of 120 participants allocated in a ratio of 2:1, 80 to nivolumab + SABR and 40 nivolumab alone to provide 80% power, one-sided type I error rate of 5% for PFS6 of 50% (worthy of pursuit) vs 35% (not worthy of pursuit). BIOSPECIMENS: Tumour tissue and serial bloods (4 time points) will be collected for translational research. CURRENT ENROLLMENT (as of Feb 2017): 2 out of 20 sites are open. NIVORAD is an investigator-initiated, cooperative-group trial led by the ALTG in collaboration with the NHMRC Clinical Trials Centre, University of Sydney and the Trans Tasman Radiation Oncology Group (TROG). Australian New Zealand Clinical Trials Registry: ACTRN12616000352404.
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TPS177
Background:
177
Lu‐PSMA‐617 (LuPSMA) is a novel radionuclide with promising activity and tolerability in metastatic, castration-resistant prostate cancer (mCRPC). Pre-clinical ...studies have shown that androgen receptor blockade with enzalutamide upregulates PSMA-receptor expression, and that PSMA-receptor blockade increases treatment response to enzalutamide. We hypothesise that concurrent administration of LuPSMA and enzalutamide will be synergistic in mCRPC. The aims of ENZA-p are to determine the activity and safety of LuPSMA and enzalutamide in men with mCRPC at high-risk of early progression on enzalutamide alone; and to identify potential prognostic and predictive biomarkers from imaging, blood, and tissue. Methods: This open-label, randomised, multicentre, phase 2 trial will recruit 160 men with mCRPC. Key eligibility criteria include progression on androgen deprivation therapy, 2 or more high-risk features for early (LDH ≥ULN; ALP ≥ULN; albumin <35 g/L; M1 disease at diagnosis; <3 years from initial diagnosis to randomisation; >5 bone metastases; visceral metastases; PSA doubling time <84 days; pain requiring opiates >14 days; prior abiraterone), no prior treatment with a novel androgen signalling inhibitor (except abiraterone), no prior chemotherapy for mCRPC, and PSMA-avid disease on positron emission tomography (PET) with
68
Ga-PSMA. Participants are randomly assigned (1:1) enzalutamide 160 mg daily or enzalutamide 160 mg daily plus LuPSMA 7.5 GBq on days 15 and 57. Two subsequent doses of Lu-PSMA will be administered if the
68
Ga-PSMA PET on day 92 shows persistent PSMA expression in the tumour. Imaging assessments include CT and technetium bone scan at baseline, day 99, then every 12 weeks;
68
Ga-PSMA-11 PET at baseline, days 15, 92, and first progression; and
18
F FDG PET at baseline and first progression. Translational samples including circulating tumour cells (CTCs), circulating tumour DNA (ctDNA) and biopsies (optional) will be collected at baseline, day 92, and first progression. The primary endpoint is PSA progression-free survival (PSA-PFS). Secondary endpoints include radiological-PFS, PSA-response rate, pain response and PFS, clinical-PFS, overall survival, health related quality of life, adverse events, and cost-effectiveness. Correlative studies include identification of prognostic and predictive biomarkers from
68
Ga-PSMA,
18
F FDG PET/CT, CTCs, and ctDNA. A sample size of 160 provides 80% power with a 2-sided type 1-error rate of 5% to detect a HR of 0.625 assuming a median PSA-PFS of 5 months with enzalutamide alone. Accrual was 5 on 13 October 2020. ENZA-p is an investigator-initiated, academic trial led by ANZUP in collaboration with the NHMRC Clinical Trials Centre, University of Sydney. Clinical trial information: NCT04419402.
As chronic antigenic stimulation from infection and autoimmunity is a feature of primary antibody deficiency (PAD), analysis of affected patients could yield insights into T-cell differentiation and ...explain how environmental exposures modify clinical phenotypes conferred by single-gene defects. CD57 marks dysfunctional T cells that have differentiated after antigenic stimulation. Indeed, while circulating CD57
CD4
T cells are normally rare, we found that they are increased in patients with PAD and markedly increased with CTLA4 haploinsufficiency or blockade. We performed single-cell RNA-seq analysis of matched CD57
CD4
T cells from blood and tonsil samples. Circulating CD57
CD4
T cells (CD4cyt) exhibited a cytotoxic transcriptome similar to that of CD8
effector cells, could kill B cells, and inhibited B-cell responses. CTLA4 restrained the formation of CD4cyt. While CD57 also marked an abundant subset of follicular helper T cells, which is consistent with their antigen-driven differentiation, this subset had a pre-exhaustion transcriptomic signature marked by TCF7, TOX, and ID3 expression and constitutive expression of CTLA4 and did not become cytotoxic even after CTLA4 inhibition. Thus, CD57
CD4
T-cell cytotoxicity and exhaustion phenotypes are compartmentalised between blood and germinal centers. CTLA4 is a key modifier of CD4
T-cell cytotoxicity, and the pathological CD4cyt phenotype is accentuated by infection.
Abstract
Introduction: Gastric cancer is one of the most common cancers worldwide, and a leading cause of cancer death. Advanced OesophagoGastric cancer (AOGC) has a poor prognosis despite treatment. ...The P2 INTEGRATE multinational 2:1 (active:placebo) randomized trial demonstrated the activity, on progression-free survival (PFS), of the oral multikinase inhibitor regorafenib (REG) in patients (pts) with refractory AOGC (Pavlakis et al JCO 2016), leading to the P3 INTEGRATE II trial (NCT02773524) currently underway. Here, we sought to identify prognostic protein biomarkers in a discovery analysis of a patient subset from INTEGRATE I.
Methods: The discovery analysis set comprised of 40 INTEGRATE I patients (12 placebo; 28 REG) selected using stratified random sampling based on quartiles of observed PFS within each arm of allocation, half from 1st quartile (worst PFS outcome) and half from 4th quartile (best PFS outcome). We profiled the plasma proteome of INTEGRATE pts using data-independent acquisition of liquid chromatography coupled with tandem mass spectrometry (SWATH-MS acquisition). Plasma collected at baseline (10µl) was analyzed with TripleTOF 6600 System (SCIEX, MA, USA). Data was searched against an “extended” spectral library generated using SwathXtendsoftware (Wu et al MCP 2016). Cox proportional hazard regression was used to assess the prognostic value of log2 protein expression level adjusted for treatment allocation.
Results: 437 proteins were identified across all 40 pt samples (>99% peptide confidence). A subset of 27 proteins were identified as candidates for possible further investigation using the verification analysis set on the basis of having p-values <0.05 (no p-value was significant after adjustment for multiple comparisons). These proteins were associated with (i) the immune system, including multiple immunoglobulin variable heavy and light chains, and proteins involved in complement activation (C09, C08G, C4BPA and C05 and others) and two serpins that regulate the acute phase response and promote cancer cell survival (AACT and A1AT); (ii) blood coagulation and angiogenesis (THBS1/PROS1/FBLN1 and others), also instrumental in tumor progression. Other proteins are known to promote local cancer cell adhesion, invasion and distant metastasis.
Conclusions: This is the first time that SWATH has been used to analyse AOGC pt samples, an otherwise challenging biofluid (undepleted plasma) for profiling. These proteins could represent a novel prognostic signature for PFS in AOGC patients, pending validation in the larger verification data set. This work highlights the potential value of incorporating proteomics into risk assessments guiding treatment strategies for patients.
Citation Format: Sarah A. Hayes, Andrew Martin, Sonia Yip, Viive M. Howell, Katrin M. Sjoquist, Eric Tsobanis, Yoon-Koo Kang, Yung-Jue Bang, Thierry Alcindor, Christopher J. O'Callaghan, Niall C. Tebbutt, John Simes, David Goldstein, Nick Pavlakis. SWATH-MS profiling identifies prognostic factors for progression-free survival (PFS) In INTEGRATE - A randomized phase II double-blind placebo-controlled study of regorafenib in refractory advanced oesophagogastric cancer (AOGC) - A study by the Australasian Gastrointestinal Trials Group (AGITG) abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4531.
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TPS332
Background: Lutetium-177
177
Lu-PSMA-617 is a novel radiolabelled small molecule that binds with high affinity to prostate-specific membrane antigen (PSMA), which is commonly ...overexpressed in prostate cancer. This treatment has demonstrated promising activity and tolerability in men progressing after multiple lines of chemotherapy and endocrine therapy. This trial will determine the activity and safety of
177
Lu-PSMA-617 compared to cabazitaxel chemotherapy in men with progressive metastatic castrate resistant prostate cancer. Methods: TheraP is an open-label, randomised, two-arm, multi-centre, phase 2 trial comparing the activity and safety of experimental treatment with
177
Lu-PSMA-617 versus standard 2
nd
line chemotherapy with cabazitaxel. Key eligibility criteria include prior chemotherapy with docetaxel; rising serum PSA; sufficient PSMA avidity according to central reviewed of imaging with PSMA PET/CT and FDG PET/CT; no discordance between FDG PET and PSMA PET. The trial will include 200 participants randomised in a 1:1 ratio to either
177
Lu-PSMA-617 intravenously every 6 weeks, 8.5 GBq for cycle 1, decreasing by 0.5 GBq with each subsequent cycle, up to maximum 6 cycles (experimental group); or, chemotherapy with cabazitaxel (20 mg/m
2
) intravenously every 3 weeks, for 10 cycles (standard group). In the event of an exceptional response to
177
Lu-PSMA-617, according to centrally-reviewed, post-therapy SPECT imaging, treatment is suspended but can recommence subsequently on progression. The primary endpoint is a 50% or greater reduction from baseline in serum PSA. Secondary endpoints include overall survival, progression-free survival (PFS), PSA-PFS, pain-PFS, radiographic-PFS, health-related quality of life, pain response, and adverse events. The outcomes of patients excluded because of discordant disease on FDG PET and PSMA PET will be reported as a tertiary objective. The study has accrued 79 of 200 planned participants from 29 January 2018 to 23 October 2018. Clinical trial information: NCT03392428.