Publications

9571 Background: Adjuvant anti-PD1 therapy reduces the risk of recurrence in resected stage III/IV melanoma and is now standard care. Limited data exist beyond registration trials. We sought to explore the use of adjuvant immunotherapy in routine clinical practice. Methods: Patients (pts) from 11 Australian centres who received adjuvant nivolumab (nivo) for resected stage III/IV melanoma were included in this study. Efficacy, toxicity, surveillance, recurrence characteristics, management and further treatment outcomes were examined. Results: 471 pts received adjuvant nivo between 8/2018 to 3/2020. 318 (68%) were male, median age 64y (range 17-94), 28 (6%) were AJCC v8 IIIA, 194 (41%) IIIB, 175 (37%) IIIC, 11 (2%) IIID, and 63 (13%) IV. 65 (14%) pts had in-transit only disease, 152 (37%) pts were sentinel lymph node biopsy (SLNB+) and only 9 (6%) of these had CLND. 128 (27%) had BRAF mutant (BRAFmt) melanoma. Median time from resection to start of adjuvant nivo was 1.8 months (mo) (range 0.2-4.0). Median FU was 17.5 mo. 256 (54%) pts completed 12 months of nivo, 86 (18%) ceased early for toxicity, 76 (16%) for disease recurrence, 25 (5%) other reasons (COVID-19 8, co-morbidities 7, pt choice 10); 28 (6%) pts were still receiving nivo at data cut. Median duration of treatment was 10.4 mo (range 0-16.8). 117 (25%) pts recurred; 76 (65%) while ON nivo and 41 (35%) OFF nivo ( > 1 month after last dose, including 20 pts who stopped early for toxicity). 24 mo RFS was 69%. Median time to recurrence was 6.0 mo (95% CI 5.1, 7.5). 56 (48%) had first recurrence with locoregional (LR) disease only and 61 (52%) had distant +/- LR recurrence. Of those who recurred with LR disease only, 46/56 (82%) underwent surgery, 15/46 (33%) then had adjuvant radiotherapy, and 15/46 (33%) had ‘second adjuvant’ therapy with BRAF/MEK inhibitors (15/21, 71% BRAFmt pts). 10/56 (37%) pts who recurred with LR disease subsequently recurred distantly. 58/80 (73%) pts received systemic therapy at either 1st or subsequent unresectable recurrence. For recurrences ON nivo, 18 pts received combination ipilimumab (ipi) and nivo (ORR 44%), 4 pts had ipi monotherapy (ORR 0%), 7 pts had anti-PD1 + investigational agent (ORR 57%), 11 pts had BRAF/MEK inhibitors (ORR 82%). 1 pt had PD with ongoing PD1 monotherapy. For recurrences OFF nivo, no patients responded to PD1 alone (n = 1) or with an investigational agent (n = 1), ipi+nivo (n = 3), ipi monotherapy (n = 4) or chemotherapy (n = 2); 6 pts received BRAF/MEK inhibitors (ORR 50%). 2-year OS was 92%. Conclusions: Despite higher rates of discontinuation due to toxicity compared with clinical trial cohorts, the efficacy data appear similar. Most early recurrences are distant, and many with LR recurrence soon recur distantly thereafter. Second line adjuvant BRAF/MEK inhibitors are frequently used for resected LR recurrence. Both ipi+nivo and BRAF/MEK inhibitors appear to have activity after distant recurrence.

LBA2 Background: Standard of care (SOC) for resectable, macroscopic stage III melanoma is therapeutic lymph node dissection (TLND) followed by adjuvant (adj) therapy with nivolumab (NIVO), pembrolizumab (PEM) or, in BRAFmut melanoma, dabrafenib + trametinib (DAB/TRAM). The recent phase 2 SWOG S1801 trial showed superior event-free survival (EFS) of neoadjuvant (neoadj) + adj PEM as compared to adj PEM (estimated 2y-EFS 72% vs 49%). Additional phase 2 trials demonstrated safety and high efficacy (77-80% 2y-EFS) of neoadj ipilimumab (IPI) 1 mg/kg + nivolumab (NIVO) 3 mg/kg, providing the rationale for testing neoadj IPI + NIVO against SOC in a phase 3 trial. Methods: In this investigator initiated, international phase 3 trial, resectable, macroscopic, nodal stage III melanoma pts, naive to ICI and BRAFi/MEKi, were randomized to receive 2 cycles of neoadj IPI 80mg + NIVO 240mg (q3w) followed by TLND, and in case of not achieving a major pathologic response (MPR) adj DAB/TRAM (150mg BID/2mg QD; 46 wks) or 11 cycles of adj NIVO (480mg; q4w; if BRAFwt) versus TLND followed by 12 cycles of adj NIVO (480mg; q4w). The primary endpoint EFS is defined as time from randomization until progression, recurrence or death due to melanoma or treatment, and was assessed using a Cox regression model. An interim analysis using a 2-sided alpha of 0.1% (Haybittle-Peto stopping rule) was planned per protocol after completing recruitment. Results: Between Aug 2021 and Dec 2023, 423 pts were randomly assigned; 212 pts to the neoadj arm and 211 to the adj arm. At data cutoff on January 12, 2024, with a median FU of 9.9 mos, significantly less events occurred in the neoadj arm vs the adj arm (28 vs 72), with HR 0.32 (99.9% CI 0.15-0.66, p<0.0001) and estimated 12-mo EFS rates of 83.7% (99.9% CI 73.8-94.8) vs 57.2% (99.9% CI 45.1-72.6) favoring the neoadj arm. In the subgroup of BRAFmut melanoma, estimated EFS rates were 83.5% and 52.1%, and in BRAFwt 83.9% and 62.4% for neoadj versus adj respectively. 58.0% of pts in the neoadj arm had an MPR, 8.0% a path partial-response (pPR), 26.4% a path non-response (pNR), 2.4% had progression before surgery and 5.2% were not reported (95% centrally reviewed). The 12-mo RFS rates according to path response were 95.1% for MPR, 76.1% for pPR and 57.0% for pNR. Systemic treatment related adverse events (AE) grade ≥3 were seen in 29.7% and 14.7% in the neoadj and adj arm; 1 pt died due to toxicity in adj arm (pneumonitis). Surgery related grade ≥3 AEs were reported in 14.6% and 14.4% respectively. Conclusions: NADINA is the first phase 3 trial that evaluates neoadj immunotherapy against SOC in melanoma, and is also the first phase 3 trial in oncology evaluating a neoadj regimen consisting of immunotherapy alone. Neoadj IPI+NIVO followed by response-driven adj treatment results in statistically significant improved EFS compared to adj NIVO and should be considered a new SOC treatment in macroscopic stage III melanoma. Clinical trial information: NCT04949113 .

Abstract Spatial technologies that query the location of cells in tissues at single-cell resolution are gaining popularity and are likely to become commonplace. The resulting data includes the X, Y coordinates of millions of cells, cell phenotypes and marker or gene expression levels. However, to date, the tools for the analysis of this data are largely underdeveloped, making us severely underpowered in our ability to extract quantifiable information. We have developed SPIAT ( Sp atial I mage A nalysis of T issues), an R package with a suite of data processing, quality control, visualization, data handling and data analysis tools. SPIAT includes our novel algorithms for the identification of cell clusters, cell margins and cell gradients, the calculation of neighbourhood proportions, and algorithms for the prediction of cell phenotypes. SPIAT also includes speedy implementations of the calculation of cell distances and detection of cell communities. This version of SPIAT is directly compatible with Opal multiplex immunohistochemistry images analysed through the HALO and InForm analysis software, but its intuitive implementation allows use with a diversity of platforms. We expect SPIAT to become a user-friendly and speedy go-to package for the spatial analysis of cells in tissues. SPIAT is available on Github: https://github.com/cancer-evolution/SPIAT

The combination of nivolumab + relatlimab is superior to nivolumab alone in the treatment of naive patients and has activity in PD-1 refractory melanoma. We had previously observed a reduced expression of LAG3 in melanoma tissue from patients with type 2 diabetes.To evaluate the impact of diabetes on oncological outcomes of patients with advanced melanoma treated with nivolumab plus the LAG3 inhibitor relatlimab we performed a retrospective multicenter study.Overall, 129 patients were included: 88 without diabetes before the treatment, 37 who were diagnosed with type 2 diabetes before the start of treatment, and 4 without diabetes before treatment who developed immune checkpoint inhibitor-induced diabetes (ICI-DM). PFS was 21.71 months (95% CI: 15.61-27.81) in patients without diabetes, 10.23 months (95% CI: 5.81-14.66) in patients with type 2 diabetes, and 50.85 months (95% CI: 23.04-78.65) in patients who developed ICI-DM. OS was 37.94 months (95% CI: 31.02-44.85) in patients without diabetes, 22.12 months (95% CI: 14.41-29.85) in those with type 2 diabetes and 57.64 months (95% CI: 42.29-72.99) in those who developed ICI-DM. Multivariate analysis showed that the presence of diabetes and LDH was correlated with OS and PFS. The mean OS was 64.63 months in subjects with low levels of glucose (< 137 mg/dl) and 36.27 months in those with high levels (hazard ratio 0.16, 95% CI: 0.04-0.58; p = 0.005). The patients whose glucose blood level increased after 3 months of treatment with nivolumab + relatinib compared to baseline (ratio of blood level at baseline/after 3 months > 1.5) had a worse prognosis than those whose glucose level had not increased. This result was observed also in subgroups treated either in first line or further lines. Patients who developed ICI-DM during the study period had better outcomes than the overall population and patients without diabetes.LAG3 inhibition for treating metastatic or unresectable melanoma has a reduced efficacy in patients with type 2 diabetes, possibly due to a low expression of LAG3 in tumor tissue. Higher level evidence should be obtained.

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 &lt;35 g/L; M1 disease at diagnosis; &lt;3 years from initial diagnosis to randomisation; &gt;5 bone metastases; visceral metastases; PSA doubling time &lt;84 days; pain requiring opiates &gt;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.

<title>Abstract</title> Three classes of BCMA-directed therapy (BDT) exist: antibody drug-conjugates (ADCs), CAR-T, and T-cell engagers (TCEs), each with distinct strengths and weaknesses. To aid clinicians in selecting between BDTs, we reviewed myeloma patients treated at Mayo Clinic with commercial or investigational BDT between 2018–2023. We identified 339 individuals (1-exposure = 297, 2-exposures = 38, 3-exposures = 4) who received 385 BDTs (ADC = 59, TCE = 134, CAR-T = 192), with median follow-up of 21-months. ADC recipients were older, with more lines of therapy (LOT), and penta-refractory disease. Compared to ADCs, CAR-T (aHR = 0.29, 95%CI = 0.20–0.43) and TCEs (aHR = 0.62, 95%CI = 0.43–0.91) had better progression-free survival (PFS) on analysis adjusted for age, the presence of extramedullary (EMD), penta-refractory disease, multi-hit high-risk cytogenetics, prior BDT, and the number of LOT in the preceding 1-year. Likewise, compared to ADCs, CAR-T (aHR = 0.28, 95%CI = 0.18–0.44) and TCEs (aHR = 0.60, 95%CI = 0.39–0.93) had superior overall survival. Prior BDT exposure negatively impacted all classes but was most striking in CAR-T, ORR 86% vs. 50% and median PFS 13-months vs. 3-months. Of relapses, 54% were extramedullary in nature, and a quarter of these cases had no history of EMD. CAR-T demonstrates superior efficacy and where feasible, should be the initial BDT. However, for patients with prior BDT or rapidly progressive disease, an alternative approach may be preferable.

Mycobacterium tuberculosis (Mtb) ranks as the most lethal human pathogen, able to fend off repeated attacks by the immune system or medications. PE_PGRS proteins are hallmarks of the pathogenicity of Mtb and contribute to its antigenic diversity, virulence, and persistence during infection. M. smegmatis is a nonpathogenic mycobacterium that naturally lacks PE_PGRS and is used as a model to express Mtb proteins. PE_PGRS has the capability to evade host immune responses and enhance the intracellular survival of M. smegmatis. Despite the intense investigations into PE_PGRS proteins, their role in tuberculosis remains elusive. We engineered the recombinant M. smegmatis strain Ms-PE_PGRS38. The result shows that PE_PGRS38 is expressed in the cell wall of M. smegmatis. PE_PGRS38 contributes to biofilm formation, confers permeability to the cell wall, and shows variable responses to exogenous stresses. PE_PGRS38 downregulated TLR4/NF-κB signaling in RAW264.7 macrophages and lung tissues of infected mice. In addition, PE_PGRS38 decreased NLRP3-dependent IL-1β release and limited pathogen-mediated inflammasome activity during infection. Moreover, PE_PGRS38 inhibited the apoptosis of RAW264.7 cells by downregulating the expression of apoptotic markers including Bax, cytochrome c, caspase-3, and caspase-9. In a nutshell, our findings demonstrate that PE_PGRS38 is a virulence factor for Mtb that enables recombinant M. smegmatis to survive by resisting and evading the host’s immune responses during infection.

Abstract Background COVID-19 infection can cause life-threatening respiratory disease. This study aimed to fully characterize the clinical features associated with postponed viral shedding time and disease progression, then develop and validate two prognostic discriminant models. Methods This study included 125 hospitalized patients with COVID-19, for whom 44 parameters were recorded, including age, gender, underlying comorbidities, epidemiological features, laboratory indexes, imaging characteristics and therapeutic regimen, et al. Fisher's exact test and Mann–Whitney test were used for feature selection. All models were developed with fourfold cross-validation, and the final performances of each model were compared by the Area Under Receiving Operating Curve (AUROC). After optimizing the parameters via L 2 regularization, prognostic discriminant models were built to predict postponed viral shedding time and disease progression of COVID-19 infection. The test set was then used to detect the predictive values via assessing models’ sensitivity and specificity. Results Sixty-nine patients had a postponed viral shedding time (&gt; 14 days), and 28 of 125 patients progressed into severe cases. Six and eleven demographic, clinical features and therapeutic regimen were significantly associated with postponed viral shedding time and disease progressing, respectively ( p &lt; 0.05). The optimal discriminant models are: y 1 (postponed viral shedding time) = − 0.244 + 0.2829x 1 (the interval from the onset of symptoms to antiviral treatment) + 0.2306x 4 (age) + 0.234x 28 (Urea) − 0.2847x 34 (Dual-antiviral therapy) + 0.3084x 38 (Treatment with antibiotics) + 0.3025x 21 (Treatment with Methylprednisolone); y 2 (disease progression) = − 0.348–0.099x 2 (interval from Jan 1st,2020 to individualized onset of symptoms) + 0.0945x 4 (age) + 0.1176x 5 (imaging characteristics) + 0.0398x 8 (short-term exposure to Wuhan) − 0.1646x 19 (lymphocyte counts) + 0.0914x 20 (Neutrophil counts) + 0.1254x 21 (Neutrphil/lymphocyte ratio) + 0.1397x 22 (C-Reactive Protein) + 0.0814x 23 (Procalcitonin) + 0.1294x 24 (Lactic dehydrogenase) + 0.1099x 29 (Creatine kinase).The output ≥ 0 predicted postponed viral shedding time or disease progressing to severe/critical state. These two models yielded the maximum AUROC and faired best in terms of prognostic performance (sensitivity of78.6%, 75%, and specificity of 66.7%, 88.9% for prediction of postponed viral shedding time and disease severity, respectively). Conclusion The two discriminant models could effectively predict the postponed viral shedding time and disease severity and could be used as early-warning tools for COVID-19.

TPS205 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 hypothesize 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 combined with enzalutamide in men with mCRPC at high-risk of early progression on enzalutamide alone; and to identify prognostic and predictive biomarkers from imaging, blood, and tissue. Methods: This open-label, randomized, multicentre, phase 2 trial will recruit 160 men with mCRPC. Key eligibility criteria include progression on androgen deprivation therapy, 2 or more risk factors for early cancer progression on enzalutamide (LDH ≥ULN; ALP ≥ULN; albumin &lt; 35 g/L; M1 disease at diagnosis; &lt; 3 years since initial diagnosis; &gt; 5 bone metastases; visceral metastases; PSA doubling time &lt; 3 months; pain requiring opiates &gt; 14 days; for castration-sensitive disease), no prior treatment with an androgen receptor pathway 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) to 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 tumor cells (CTCs), circulating tumor 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 90 on 12 October 2021. Clinical trial information: NCT04419402.