Brief Report: Real-World Toxicity and Survival of Combination Immunotherapy in Pleural Mesothelioma-RIOMeso

BACKGROUND

Australia has one of the highest rates of asbestos-associated diseases. Mesothelioma remains an area of unmet need with a 5-year overall survival of 10%. First-line immunotherapy with ipilimumab and nivolumab is now a standard of care for unresectable pleural mesothelioma following the CheckMate 743 trial, with supportive data from the later line single-arm MAPS2 trial. RIOMeso evaluates survival and toxicity of this regimen in real-world practice.

METHODS

Demographic and clinicopathologic data of Australian patients treated with ipilimumab and nivolumab in first- and subsequent-line settings for pleural mesothelioma were collected retrospectively. Survival was reported using the Kaplan-Meier method and compared between subgroups with the log-rank test. Toxicity was investigator assessed using Common Terminology Criteria for Adverse Events version 5.0.

RESULTS

A total of 119 patients were identified from 11 centers. The median age was 72 years, 83% were male, 92% had Eastern Cooperative Oncology Group less than or equal to 1, 50% were past or current smokers, and 78% had known asbestos exposure. In addition, 50% were epithelioid, 19% sarcomatoid, 14% biphasic, and 17% unavailable. Ipilimumab and nivolumab were used first line in 75% of patients. Median overall survival (mOS) was 14.5 months (95% confidence interval [CI]: 13.0-not reached [NR]) for the entire cohort. For patients treated first line, mOS was 14.5 months (95% CI: 12.5-NR) and in second- or later-line patients was 15.4 months (95% CI: 11.2-NR). There was no statistically significant difference in mOS for epithelioid patients compared with nonepithelioid (19.1 mo [95% CI: 15.4-NR] versus 13.0 mo [95% CI: 9.7-NR], respectively, p = 0.064). Furthermore, 24% of the patients had a Common Terminology Criteria for Adverse Events grade greater than or equal to 3 adverse events, including three treatment-related deaths. Colitis was the most frequent adverse event.

CONCLUSIONS

Combination immunotherapy in real-world practice has poorer survival outcomes and seems more toxic compared with clinical trial data. This is the first detailed report of real-world survival and toxicity outcomes using ipilimumab and nivolumab treatment of pleural mesothelioma.

Objective response rate and progression-free survival as surrogates for overall survival treatment effect: A meta-analysis across diverse tumour groups and contemporary therapies

BACKGROUND

Overall survival (OS) results from randomized control trials (RCT) provide the strongest evidence for efficacy of anti-cancer treatments but can take a considerable amount of time to mature. Progression free survival (PFS) and objective response rate (ORR) are used as an early surrogate of OS treatment effect however their validity remains unclear. Our study aims to comprehensively evaluate ORR and PFS as surrogates for OS treatment effect across tumor groups and treatment types.

MATERIAL AND METHODS

Phase 3 RCTs in solid malignancies that reported OS/PFS and ORR published between 1st of January 2010 and 30th of June 2022 were evaluated. The relationship of surrogate endpoints and OS treatment effect was assessed via weighted linear regression. The coefficient of determination (R2) quantified the fit of the regression model.

RESULTS

675 phase 3 RCT comprising of 350 112 patients were analysed. ORR (R2 of 0.10) and PFS (R2 of 0.38) were poor surrogate markers of OS treatment effect. The strength of surrogacy differed within treatment and tumour groups. PFS had the highest R2 for chemotherapy (0.56) and lowest for targeted therapy (0.40). PFS had the highest level of surrogacy for melanoma (R2 = 0.72) and pancreatic cancer (R2 = 0.70) compared to other tumour groups. Importantly ORR and PFS were also poorly correlated to each other (R2 = 0.33).

CONCLUSIONS

ORR and PFS were poor trial-level surrogate markers of OS. The surrogacy performance of ORR and PFS differed by treatment and malignancy sub-type.

Telehealth in oncology: a cost analysis to evaluate the financial impact of implementing regional trial hubs within a phase 3 cancer clinical trial

This cost analysis, from a societal perspective, compared the cost difference of a networked teletrial model (NTTM) with four regional hubs versus conventional trial operation at a single metropolitan specialist centre. The Australian phase 3 cancer interventional randomised controlled trial included 152 of 328 regional participants (patient enrolment 2018-2021; 6-month primary end point). The NTTM significantly reduced (AU$2155 per patient) patient travel cost and time and lost productivity.

First-Line Selpercatinib or Chemotherapy and Pembrolizumab in RET Fusion-Positive NSCLC

BACKGROUND

Selpercatinib, a highly selective potent and brain-penetrant RET inhibitor, was shown to have efficacy in patients with advanced RET fusion-positive non-small-cell lung cancer (NSCLC) in a nonrandomized phase 1-2 study.

METHODS

In a randomized phase 3 trial, we evaluated the efficacy and safety of first-line selpercatinib as compared with control treatment that consisted of platinum-based chemotherapy with or without pembrolizumab at the investigator's discretion. The primary end point was progression-free survival assessed by blinded independent central review in both the intention-to-treat-pembrolizumab population (i.e., patients whose physicians had planned to treat them with pembrolizumab in the event that they were assigned to the control group) and the overall intention-to-treat population. Crossover from the control group to the selpercatinib group was allowed if disease progression as assessed by blinded independent central review occurred during receipt of control treatment.

RESULTS

In total, 212 patients underwent randomization in the intention-to-treat-pembrolizumab population. At the time of the preplanned interim efficacy analysis, median progression-free survival was 24.8 months (95% confidence interval [CI], 16.9 to not estimable) with selpercatinib and 11.2 months (95% CI, 8.8 to 16.8) with control treatment (hazard ratio for progression or death, 0.46; 95% CI, 0.31 to 0.70; P<0.001). The percentage of patients with an objective response was 84% (95% CI, 76 to 90) with selpercatinib and 65% (95% CI, 54 to 75) with control treatment. The cause-specific hazard ratio for the time to progression affecting the central nervous system was 0.28 (95% CI, 0.12 to 0.68). Efficacy results in the overall intention-to-treat population (261 patients) were similar to those in the intention-to-treat-pembrolizumab population. The adverse events that occurred with selpercatinib and control treatment were consistent with those previously reported.

CONCLUSIONS

Treatment with selpercatinib led to significantly longer progression-free survival than platinum-based chemotherapy with or without pembrolizumab among patients with advanced RET fusion-positive NSCLC. (Funded by Eli Lilly and others; ClinicalTrials.gov number, NCT04194944.).

A Phase 1b/2 Study of Alpelisib in Combination with Cetuximab in Patients with Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma

BACKGROUND

Alpelisib in combination with cetuximab showed synergistic anti-tumour activity in head and neck squamous cell carcinoma (HNSCC) models.

OBJECTIVES

The recommended phase 2 dose (RP2D) was determined in a phase 1b dose-escalation study. Phase 2 evaluated anti-tumour activity with a randomised part in cetuximab-naïve patients and a non-randomised part in cetuximab-resistant patients.

PATIENTS AND METHODS

 Alpelisib was administered in 28 d cycles as whole tablets, suspension from crushed tablets or suspension from dispersible tablets in patients with platinum-resistant, recurrent/metastatic HNSCC.

RESULTS

The RP2D determined for alpelisib was 300 mg/d. Alpelisib-cetuximab achieved an overall response rate of 25% and 9.9% and disease control rate of 75% and 43.7% in phase 1b and phase 2 studies, respectively. Median progression-free survival (PFS) per central review was 86 d for combination treatment and 87 d for cetuximab monotherapy (unadjusted HR 1.12; 95% CI 0.69-1.82; P > 0.05). When adjusted for baseline covariates [sum of longest diameters from central data, haemoglobin and white blood cell (WBC), the results favoured combination treatment (adjusted HR 0.54; 95% CI 0.30-0.97; P = 0.039). PFS per investigator assessment resulted in an unadjusted HR of 0.76 (95% CI 0.49-1.19; P > 0.05) favouring combination treatment. The median PFS in cetuximab-resistant patients was 3.9 months.

CONCLUSIONS

The addition of alpelisib to cetuximab did not demonstrate a PFS benefit in cetuximab-naïve patients with advanced HNSCC. The alpelisib-cetuximab combination showed moderate activity in cetuximab-resistant patients, with a consistent safety profile.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT01602315; EudraCT 2011-006017-34.

An NKG2A biased immune response confers protection for infection, autoimmune disease, and cancer

Infection, autoimmunity, and cancer are the principal human health challenges of the 21st century and major contributors to human death and disease. Often regarded as distinct ends of the immunological spectrum, recent studies have hinted there may be more overlap between these diseases than appears. For example, pathogenic inflammation has been demonstrated as conserved between infection and autoimmune settings. T resident memory (TRM) cells have been highlighted as beneficial for infection and cancer. However, these findings are limited by patient number and disease scope; exact immunological factors shared across disease remain elusive. Here, we integrate large-scale deeply clinically and biologically phenotyped human cohorts of 526 patients with infection, 162 with lupus, and 11,180 with cancer. We identify an NKG2A+ immune bias as associative with protection against disease severity, mortality, and autoimmune and post-acute chronic disease. We reveal that NKG2A+ CD8+ T cells correlate with reduced inflammation, increased humoral immunity, and resemble TRM cells. Our results suggest that an NKG2A+ bias is a pan-disease immunological factor of protection and thus supports recent suggestions that there is immunological overlap between infection, autoimmunity, and cancer. Our findings underscore the promotion of an NKG2A+ biased response as a putative therapeutic strategy.

SABRSeq: A Randomized Phase Ib Trial of SABR Sequencing with Pembrolizumab in Metastatic Non-Small Cell Lung Cancer (NSCLC)

PURPOSE/OBJECTIVE(S)

The optimal sequencing of stereotactic ablative body radiotherapy (SABR) with anti-PD1 checkpoint blockade is unknown. The purpose of SABRseq was to assess the toxicity of the combination of SABR delivered either before or after the commencement of pembrolizumab. The central hypothesis is that the treatment combination will have a safety profile that is clinically acceptable and demonstrate anti-tumor efficacy. Furthermore, we hypothesize that differences in systemic immune activation will be observed between treatment arms.

MATERIALS/METHODS

This was a single institutional phase Ib randomized clinical trial (Trial ID NCT03307759). Eligible patients had metastatic NSCLC, ECOG performance 0-1, and had not received prior checkpoint immunotherapy, high-dose radiation (>36 Gy) within 6 months, or either systemic or radiation therapy within 4 weeks of randomization. Eligible patients had either TPS≥50% PD-L1 expression in the first-line or TPS≥1% PD-L1 expression with prior chemotherapy exposure. Patients were randomized to SABR before the commencement of pembrolizumab [ARM1] or SABR commencing after pembrolizumab [ARM2]. SABR was delivered in a single fraction of 18-20 Gy to 1-3 lesions. The primary endpoint was treatment-related adverse events (AE's) related to SABR and/or pembrolizumab. Secondary endpoints included best overall response (BOR), overall survival (OS), and progression-free survival (PFS). Translational objectives included the evaluation of longitudinal changes in immunological cellular subsets within peripheral blood to explore changes in systemic immunity and circulating tumor DNA (ctDNA) dynamics.

RESULTS

Between December 2017 and December 2019, 13 patients were randomized. The median follow-up was 37 months. The study was closed early due to poor accrual. Median age was 66 years, with 11 patients (84%) having adenocarcinoma. Nine (69%) were enrolled in the first-line setting. The median [range] number of lesions was 6 [3-11]. The median [range] cycles of pembrolizumab delivered in ARM 1 was 13 [12-32] and ARM 2 was 9 [3-34]. Grade 3 treatment-related AEs were experienced in 0 of 5 patients in ARM1 and in 1 of 8 patients in ARM 2 (hyperglycemia). There were no grade 4 or 5 adverse events reported. The BOR by both RECIST and iRECIST criteria was CR in one patient, PR in seven patients, SD in five patients. Median (95% Cis) PFS was 12.4 months (6.3-21.0), and median (95% Cis) OS was 47.1 months (12.6-not reached; 2-year point estimate 62% [31-82]). Mass cytometry was used on serial peripheral blood samples to examine changes in the frequency of immune cells, changes in T cell activation, differentiation and functional polarization state. Targeted sequencing was performed to assess ctDNA. Translational outcomes will be presented.

CONCLUSION

There was no evidence of a concerning safety signal from either SABR before or after start of pembrolizumab. The combination demonstrated activity with promising PFS and OS and is worthy of evaluation in larger randomized trials.

Abstract 1126: Disease monitoring with comprehensive genomics provides evidence of mechanism of action and immune evasion in patients receiving an individualized neoantigen cancer vaccine

Therapeutic vaccines hold promise to broaden the potency of immune checkpoint blockade (ICB) therapy in tumors lacking immune reactivity. A heterologous chimpanzee adenovirus (ChAd68) and self-amplifying mRNA (samRNA)-based individualized neoantigen vaccine regimen in combination with nivolumab 480 mg IV and ipilimumab 30mg SC (NCT03639714) has previously demonstrated safety, durable immunogenicity, and clinical benefit in patients with previously treated metastatic disease. Genomic correlates of response were studied over time in 29 patients (13 MSS-CRC, 13 GEA, 3 NSCLC) to understand novel mechanisms of action. Exome and transcriptome sequencing from archival biopsies was used for neoantigen selection. Monthly circulating tumor DNA (ctDNA) samples were collected for monitoring using a comprehensive tumor-naïve and tumor-informed hybrid-capture based ctDNA assay. Paired pre- and post-vaccine tumor transcriptomes were analyzed for 10 patients with 6 having accompanying DNA T cell receptor Β CDR3 repertoire sequencing (TCRseq) in biopsies and longitudinal PBMCs. Prior to vaccination patient tumors were not enriched for immune infiltration or tumor mutation burden (TMB), median 4.3 mut/Mb (range: 2-17 mut/Mb). Minimal neoantigen and mutation drift was observed with a median of 92.5% of neoantigens (range: 45-100%) and a median of 84% (range: 24-99%) of individual mutations detected in biopsies and ctDNA. Notably, paired pre- and post-vaccine biopsy gene expression analyses show upregulation in gene signatures associated with immune infiltration aligning with evidence of T cell expansion measured by significantly expanding CDR3 clonotypes (p &lt0.01). Longitudinal TCRseq in PBMCs demonstrate vaccine induced TCR repertoire dynamics and expanding and contracting clones observed in tumor biopsies could be monitored throughout treatment. In 4 patients the most drastic TCR repertoire changes were observed at time points measured after a 2nd dose of ChAd68. Lastly, we observe evidence of acquired immune evasion through ctDNA monitoring in two patients each following a year of study treatment. One GEA patient acquired HLA-LOH after remaining stable on treatment and one MSS-CRC with a molecular response (MR) for &gt7 months acquired novel biallelic loss-of-function mutations in TAP1 following 1 year of study treatment. We demonstrate that our neoantigen-directed immunotherapy regimen drives durable immune pressure on the tumor in patients with advanced disease where CPI alone has provided minimal benefit. Further, the evidence of acquired resistance supports the induction of immune pressure on tumors following individualized neoantigen vaccination. Comprehensive ctDNA longitudinal monitoring enables real-time assessment of clinical response and acquired resistance.

Citation Format: Desiree Schenk, Rita Zhou, Olivia Petrillo, Alexis Mantilla, Italo Faria do Valle, Steven Maron, Brian S. Henick, Chih-Yi Liao, Daniel V.T. Catenacci, Sameek Roychowdhury, Benjamin Solomon, Alexander I. Spira, Ankur Dhanik, Andrew R. Fergusson, Karin Jooss, Matthew Davis. Disease monitoring with comprehensive genomics provides evidence of mechanism of action and immune evasion in patients receiving an individualized neoantigen cancer vaccine [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1126.

Bi-allelic ATG4D variants are associated with a neurodevelopmental disorder characterized by speech and motor impairment

Autophagy regulates the degradation of damaged organelles and protein aggregates, and is critical for neuronal development, homeostasis, and maintenance, yet few neurodevelopmental disorders have been associated with pathogenic variants in genes encoding autophagy-related proteins. We report three individuals from two unrelated families with a neurodevelopmental disorder characterized by speech and motor impairment, and similar facial characteristics. Rare, conserved, bi-allelic variants were identified in ATG4D, encoding one of four ATG4 cysteine proteases important for autophagosome biogenesis, a hallmark of autophagy. Autophagosome biogenesis and induction of autophagy were intact in cells from affected individuals. However, studies evaluating the predominant substrate of ATG4D, GABARAPL1, demonstrated that three of the four ATG4D patient variants functionally impair ATG4D activity. GABARAPL1 is cleaved or "primed" by ATG4D and an in vitro GABARAPL1 priming assay revealed decreased priming activity for three of the four ATG4D variants. Furthermore, a rescue experiment performed in an ATG4 tetra knockout cell line, in which all four ATG4 isoforms were knocked out by gene editing, showed decreased GABARAPL1 priming activity for the two ATG4D missense variants located in the cysteine protease domain required for priming, suggesting that these variants impair the function of ATG4D. The clinical, bioinformatic, and functional data suggest that bi-allelic loss-of-function variants in ATG4D contribute to the pathogenesis of this syndromic neurodevelopmental disorder.

Treatment Characteristics and Real-World Progression-Free Survival in Patients With Unresectable Stage III NSCLC Who Received Durvalumab After Chemoradiotherapy: Findings From the PACIFIC-R Study

INTRODUCTION

The phase 3 PACIFIC trial established consolidation therapy with durvalumab as standard of care for patients with unresectable, stage III NSCLC and no disease progression after definitive chemoradiotherapy (CRT). The observational PACIFIC-R study assesses the real-world effectiveness of durvalumab in patients from an early access program. Here, we report treatment characteristics and a preplanned analysis of real-world progression-free survival (rwPFS).

METHODS

PACIFIC-R (NCT03798535) is an ongoing, international, retrospective study of patients who started durvalumab (intravenously; 10 mg/kg every 2 wk) within an early access program between September 2017 and December 2018. The primary end points are investigator-assessed rwPFS and overall survival (analyzed by Kaplan-Meier method).

RESULTS

As of November 30, 2020, the full analysis set comprised 1399 patients from 11 countries (median follow-up duration, 23.5 mo). Patients received durvalumab for a median of 11.0 months. Median rwPFS was 21.7 months (95% confidence interval: 19.1-24.5). RwPFS was numerically longer among patients who received concurrent versus sequential CRT (median, 23.7 versus 19.3 mo) and among patients with programmed cell death-ligand 1 expression greater than or equal to 1% versus less than 1% (22.4 versus 15.6 mo). Overall, 16.5% of the patients had adverse events leading to treatment discontinuation; 9.5% of all patients discontinued because of pneumonitis or interstitial lung disease.

CONCLUSIONS

Consolidation durvalumab after definitive CRT was well tolerated and effective in this large, real-world cohort study of patients with unresectable, stage III NSCLC. As expected, rwPFS was longer among patients who received concurrent versus sequential CRT and patients with higher programmed cell death-ligand 1 expression. Nevertheless, favorable rwPFS outcomes were observed regardless of these factors.

A real-world study of second or later-line osimertinib in patients with EGFR T790M-positive NSCLC: the final ASTRIS data

Aim: Report the final analysis from ASTRIS, the largest real-world study of second-/later-line osimertinib in advanced/metastatic EGFR T790M non-small-cell lung cancer (NSCLC). Methods: Patients with advanced/metastatic EGFR T790M NSCLC and prior EGFR-TKI treatment, received once-daily osimertinib 80 mg. Primary end point: overall survival (OS); secondary end points: progression-free survival (PFS), time-to-treatment discontinuation (TTD) and response rate. Safety was also recorded. Results: In 3014 patients, median OS: 22.8 months (21.6-23.8), median PFS: 11.1 months (11.0-12.0), median TTD: 13.5 months (12.6-13.9), and response rate: 57.3% (55.5-59.2). All end points reported with 95% CIs . Numerically longer median OS was observed in patients with baseline WHO performance status <2 versus 2 (24.0 vs 11.1 months) and those without versus with brain/leptomeningeal metastases (25.4 vs 18.0 months). No new safety signals were identified. Conclusion: Second-/later-line osimertinib demonstrated real-world clinical benefit and safety in advanced/metastatic EGFR T790M NSCLC. Clinical Trial Registration: NCT02474355 (ClinicalTrials.gov).

Investigating the role of inflammation in keratoconus: A retrospective analysis of 551 eyes

PURPOSE

Keratoconus (KCN), classically defined as a noninflammatory corneal ectasia, was recently associated with chronic inflammation. This study aimed to further evaluate the association between inflammation and KCN severity by assessing patient tear films.

METHODS

Retrospective chart review of consecutive patients (July 2016-February 2020) referred to a tertiary KCN centre. Using tomography Kmax values, the worst-eyes of patients with a diagnosis of KCN and tear film test results were included. Eyes were stratified as matrix metalloproteinase-9 (MMP9) positive or negative and analyzed using independent t and Pearson chi-squared tests. A p-value ≤ 0.05 was considered significant.

RESULTS

551 (51.40%) unilateral eyes were included. Mean age was 30.1 years and 70.1% were male. 55.5% of the eyes were MMP9 positive. Mean corrected distance visual acuity was 20/30^<συπ>-3</sup> Snellen and Kmax was 60.1 Diopters. MMP9 positive eyes had a higher Kmax (p = 0.048), and were more likely from patients who were male (p < 0.001), had a paediatric history of asthma (p = 0.042), and used glasses (p = 0.041). MMP9 negative eyes more likely corresponded to soft contact lens users (p = 0.012). No other significant differences were found in risk factors, topography, tomography, and tear film osmolarity.

CONCLUSION

MMP9 positive keratoconic eyes had significantly higher Kmax readings which may correlate with increased disease severity, supporting an association between keratoconus and inflammation. Further research is warranted to evaluate the role of targeted therapy and contact lens use on MMP9 levels in keratoconic eyes and whether disease progression is affected.

Comorbidity between lung cancer and COVID-19 pneumonia: role of immunoregulatory gene transcripts in high ACE2-expressing normal lung

BACKGROUND

SARS-CoV-2 (COVID-19) elicits a T-cell antigen-mediated immune response of variable efficacy. To understand this variability, we explored transcriptomic expression of angiotensin-converting enzyme 2 (ACE2, the SARS-CoV-2 receptor) and of immunoregulatory genes in normal lung tissues from patients with non-small cell lung cancer (NSCLC).

METHODS

This study used the transcriptomic and the clinical data for NSCLC patients generated during the CHEMORES study [n = 123 primary resected (early-stage) NSCLC] and the WINTHER clinical trial (n = 32 metastatic NSCLC).

RESULTS

We identified patient subgroups with high and low ACE2 expression (p = 1.55 × 10^-19) in normal lung tissue, presumed to be at higher and lower risk, respectively, of developing severe COVID-19 should they become infected. ACE2 transcript expression in normal lung tissues (but not in tumor tissue) of patients with NSCLC was higher in individuals with more advanced disease. High-ACE2 expressors had significantly higher levels of CD8+ cytotoxic T lymphocytes and natural killer cells but with presumably impaired function by high Thymocyte Selection-Associated High Mobility Group Box Protein TOX (TOX) expression. In addition, immune checkpoint-related molecules - PD-L1, CTLA-4, PD-1, and TIGIT - are more highly expressed in normal (but not tumor) lung tissues; these molecules might dampen immune response to either viruses or cancer. Importantly, however, high inducible T-cell co-stimulator (ICOS), which can amplify immune and cytokine reactivity, significantly correlated with high ACE2 expression in univariable analysis of normal lung (but not lung tumor tissue).

CONCLUSIONS

We report a normal lung immune-tolerant state that may explain a potential comorbidity risk between two diseases - NSCLC and susceptibility to COVID-19 pneumonia. Further, a NSCLC patient subgroup has normal lung tissue expressing high ACE2 and high ICOS transcripts, the latter potentially promoting a hyperimmune response, and possibly leading to severe COVID-19 pulmonary compromise.

Transcriptomics in Tumor and Normal Lung Tissues Identify Patients With Early-Stage Non-Small-Cell Lung Cancer With High Risk of Postsurgery Recurrence Who May Benefit From Adjuvant Therapies

PURPOSE

The prognosis of patients with non-small-cell lung cancer (NSCLC), traditionally determined by anatomic histology and TNM staging, neglects the biological features of the tumor that may be important in determining patient outcome and guiding therapeutic interventions. Identifying patients with NSCLC at increased risk of recurrence after curative-intent surgery remains an important unmet need so that known effective adjuvant treatments can be offered to those at highest risk of recurrence.

METHODS

Relative gene expression level in the primary tumor and normal bronchial tissues was used to retrospectively assess their association with disease-free survival (DFS) in a cohort of 120 patients with NSCLC who underwent curative-intent surgery.

RESULTS

Low versus high Digital Display Precision Predictor (DDPP) score (a measure of relative gene expression) was significantly associated with shorter DFS (highest recurrence risk; P = .006) in all patients and in patients with TNM stages 1-2 (P = .00051; n = 83). For patients with stages 1-2 and low DDPP score (n = 29), adjuvant chemotherapy was associated with improved DFS (P = .0041). High co-overexpression of CTLA-4, PD-L1, and ICOS in normal lung (28 of 120 patients) was also significantly associated with decreased DFS (P = .0013), suggesting an immune tolerance to tumor neoantigens in some patients. Patients with DDPP low and immunotolerant normal tissue had the shortest DFS (P = 2.12E-11).

CONCLUSION

TNM stage, DDPP score, and immune competence status of normal lung are independent prognostic factors in multivariate analysis. Our findings open new avenues for prospective prognostic assessment and treatment assignment on the basis of transcriptomic profiling of tumor and normal lung tissue in patients with NSCLC.

Abstract CT223: Updated efficacy and safety from the phase 3 CROWN study of first-line lorlatinib vs crizotinib in advanced anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC)

Background: Lorlatinib improved progression-free survival (PFS) and demonstrated intracranial (IC) activity in patients (pts) with untreated advanced ALK+ NSCLC in the interim analysis of the randomized, Phase 3, CROWN study of lorlatinib vs crizotinib. We report updated 36-month follow-up data.

Methods: 296 pts with previously untreated advanced ALK+ NSCLC were randomized 1:1 to oral lorlatinib (100 mg QD; n=149) or crizotinib (250 mg BID; n=147), stratified by presence of CNS metastases (mets) and ethnicity. Primary endpoint: PFS by blinded independent central review (BICR). Secondary endpoints included overall survival, PFS by investigator, and objective response (OR), IC-OR, IC time to progression (IC-TTP), duration of response (DR), IC-DR (all by BICR), and safety.

Results: At data cutoff (Sep 20, 2021), median duration of follow-up for PFS was 36.7 months for lorlatinib and 29.3 months for crizotinib. Median PFS by BICR was NR (95% CI, NR-NR) for lorlatinib and 9.3 months (95% CI, 7.6-11.1) for crizotinib (HR, 0.27; 95% CI, 0.18-0.39). PFS by investigator results were similar (Table). For pts with brain mets at baseline (n=37 lorlatinib/n=39 crizotinib), the HR for IC-TTP for lorlatinib vs crizotinib was 0.10 (95% CI, 0.04-0.27), and for pts without brain mets (n=112/n=108) was 0.02 (95% CI, 0.002-0.14). OR, IC-OR, DR, and IC-DR were all improved with lorlatinib vs crizotinib (Table). All-cause grade 3-4 adverse events (AEs) and AEs leading to treatment discontinuation were reported in 76% and 7% of pts with lorlatinib and 57% and 10% of pts with crizotinib, respectively. No new safety signals emerged.

Conclusions: These updated long-term data from CROWN confirm the efficacy of lorlatinib over crizotinib in pts with treatment-naïve ALK+ NSCLC, with no new safety signals detected, and support the use of lorlatinib in pts with untreated ALK+ NSCLC with and without brain mets. Summary of other efficacy resultsa

Clinical trial information: NCT03052608

Funding: Pfizer Inc.

ITT population Lorlatinib(n=149) Crizotinib(n=147) % alive without progression at:12 mo (95% CI) 78 (70–84) 38 (29–47) 24 68 (60–75) 22 (14–30) 36 64 (55–71) 19 (12–27) Median PFS by investigator, mo (95% CI) NR (NR–NR) 9.1 (7.4–10.9) HR (95% CI) 0.19 (0.13–0.27) Confirmed OR, n (%) [95% CI] 115 (77) [70–84] 86 (59) [50–67] Median DR,b mo (95% CI) NR (NR–NR) 9.6 (9.0–12.9) Patients with measurable or nonmeasurable brain metastases at baseline (n=37) (n=39) Median PFS, mo (95% CI) NR (18.2–NR) 7.2 (3.7–9.2) HR (95% CI) 0.21 (0.10–0.44) Confirmed IC-OR, n (%) [95% CI] 24 (65) [48–80] 7 (18) [8–34] Complete response, n (%) 22 (60) 5 (13) Median IC-DR,b mo (95% CI) NR (NR–NR) 9.4 (6.0–11.1) Patients without brain metastases at baseline (n=112) (n=108) Median PFS, mo (95% CI) NR (NR–NR) 11.0 (9.0–14.6) HR (95% CI) 0.29 (0.19–0.44) aBy blinded independent central review unless stated otherwise. bIn patients with a confirmed complete or partial response. CI, confidence interval; DR, duration of response; HR, hazard ratio; ITT, intention- to-treat; NR, not reached; IC, intracranial; OR, objective response; PFS, progression-free survival.

Citation Format: Benjamin Solomon, Todd Bauer, Tony Mok, Geoffrey Liu, Julien Mazieres, Filippo de Marinis, Yasushi Goto, Dong-Wan Kim, Yi-Long Wu, Mikhail Dvorkin, Jacek Jassem, Froylán López-López, Ross Soo, Anna Polli, Elisa Dall'O, Laura Iadeluca, Francesca Toffalorio, Enriqueta Felip. Updated efficacy and safety from the phase 3 CROWN study of first-line lorlatinib vs crizotinib in advanced anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT223.

Abstract 1238: Comprehensive ctDNA monitoring provides early signal of clinical benefit with a novel personalized neoantigen directed immunotherapy for late-stage cancer patients

Neoantigen directed immunotherapy holds promise to increase the likelihood of patients with solid tumor devoid of immune infiltration benefiting from immune checkpoint immunotherapy (CPI). A heterologous prime-boost vaccination approach consisting of Chimpanzee Adenovirus (ChAd) prime and multiple self-amplifying mRNA (SAM) boosts, delivering 20 neoantigens, has been evaluated in a Phase 1/2 clinical trial in late-stage solid tumor patients in combination with nivolumab and ipilimumab (NCT03639714). Neoantigen dynamics, tumor burden and genomic correlates of response were studied over time in 20 patients (8 GEA, 2 NSCLC, 10 MSS-CRC). Exome sequences from archival (sample used for neoantigen selection), baseline (start of immunization) and on-treatment biopsies were analyzed for 20, 16 and 10 patients respectively. Paired pre- and post-vaccine tumor transcriptomes were analyzed for 6 patients. Personalized capture baits were designed for all non-synonymous mutations detected in archival biopsies (mean 146; range: 67-402) for ctDNA monitoring. Longitudinal ctDNA samples were collected monthly on treatment (mean 7; range: 1-18). ctDNA duplex UMI libraries were captured and sequenced to a target mean raw depth &gt;80,000x and reduced to 3x per strand consensus duplex reads. The majority of vaccine neoantigens were detected in ctDNA (87%; range 45%-100%) and mean neoantigen variant allele frequency (VAF) strongly correlated with all monitored mutations VAF (R2 = 0.90, p &lt; 0.0001) through treatment. The percentage of vaccine neoantigens detected was higher than that for all monitored mutations in the same samples with a median of 80% (21%-98%) in ctDNA and 70% (44%-100%) in biopsies. Five of 9 MSS-CRC patients with measurable baseline ctDNA achieved molecular responses (MR, &gt;50% reduction in ctDNA from baseline) that correlated with OS and PFS, and in some patients, was accompanied by radiologic tumor shrinkage. One MSS-CRC patient with MR for &gt;7 months acquired novel biallelic loss-of-function mutations in TAP1 following 1 year of study treatment. Differential gene expression analysis from paired pre- and post-vaccine biopsies (including 2 MSS-CRC pairs with MR) demonstrated significant upregulation in gene signatures associated with immune-inflamed tumor microenvironments including interferon alpha and gamma responses. We demonstrate that tumor-informed neoantigen selection and vaccine manufacturing while patients receive chemotherapy is feasible, since the majority of neoantigens are retained in the tumor post-chemotherapy. Further, neoantigen-directed immunotherapy appears to drive clinical benefit in patients with advanced MSS-CRC tumors, where CPI alone has provided minimal benefit. Comprehensive ctDNA longitudinal monitoring enables real time assessment of clinical response and acquired resistance.

Citation Format: Desiree Schenck, Rita Zhou, Alexis Mantilla, Oliver Spiro, Taylor Patch, Adrienne Johnson, Daniel Navarro Gomez, Brian S. Henick, Chih-Yi Liao, Sameek Roychowdhury, Steve Maron, Benjamin Solomon, Alexander I. Spira, Daniel V. Catenacci, Andrew R. Fergusson, Raphael F. Rousseau, Karin Jooss, Matthew J. Davis. Comprehensive ctDNA monitoring provides early signal of clinical benefit with a novel personalized neoantigen directed immunotherapy for late-stage cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1238.

Abstract CT033: KontRASt-01: A phase Ib/II, dose-escalation study of JDQ443 in patients (pts) with advanced, KRAS G12C-mutated solid tumors

Background: KRAS G12C oncogenic mutations occur in ~13% of non-small cell lung cancers (NSCLCs) and up to 4% of other solid tumors. JDQ443 is a selective, covalent, orally bioavailable, investigational KRASG12C inhibitor that irreversibly traps KRASG12C in the inactive, GDP-bound state. JDQ443 is structurally unique and forms novel interactions with KRAS in the switch II pocket.

Methods: KontRASt-01 (NCT04699188) is a Phase Ib/II, open-label, multicenter, dose-escalation and dose-expansion trial of JDQ443 as monotherapy or in combination with TNO155 (SHP2 inhibitor) and/or tislelizumab (anti-PD-1 monoclonal antibody). Primary objectives of dose escalation are to assess safety and tolerability, and identify the maximum tolerated doses (MTDs) and/or recommended doses (RDs) and regimens for future studies. The primary objective of dose expansion is to assess efficacy. Key inclusion criteria: advanced, KRAS G12C-mutated solid tumors; previous standard-of-care treatment; age ≥18 yrs; ECOG PS 0-1. Key exclusion criteria for the JDQ443 monotherapy arm: active brain metastases, prior KRASG12C inhibitor treatment. Here, we present preliminary results for JDQ443 monotherapy dose escalation.

Results: As of Nov 3, 2021, 39 pts were treated with JDQ443 PO continuously across 4 dose levels: 200 mg once daily (QD) (n=10), 400 mg QD (n=11), 200 mg twice daily (BID) (n=11), and 300 mg BID (n=7). Median age was 60 yrs (range 26-76), median prior lines of therapy was 3 (range 1-7), and indications included NSCLC (n=20) and colorectal cancer (CRC) (n=16). Median duration of exposure was 9.1 wks (range 0.9-21), with ongoing treatment in most pts (61.5%) at the time of cut-off. Treatment-related adverse events (TRAEs) occurred in 25 (64.1%) pts. Most TRAEs were Grade (Gr) 1-2. Four Gr 3 TRAEs occurred in 4 (10.3%) separate pts; there were no Gr 4-5 TRAEs. The most common TRAEs (occurring in ≥10% of pts) were fatigue (25.6%), nausea (15.4%), edema (12.8%), pruritus (10.3%), and vomiting (10.3%). There was one DLT (Gr 3 fatigue) and one treatment-related serious AE (Gr 3 photosensitivity reaction), each in separate pts treated at 300 mg BID. TRAEs led to dose reduction in 1 pt and discontinuation in 1 pt. A MTD was not reached. The RD was declared as 200 mg BID. At the RD, PK and PD modeling for JDQ443 predicted average KRASG12C target occupancy of &gt;90% in &gt;82% of pts. Using an efficacy cut-off date of Dec 13, 2021, for the 20 pts with NSCLC among the same 39 pts, the ORR (confirmed complete response or partial response) by RECIST 1.1 was 30.0% (6/20) across dose levels and 43.0% (3/7) at the RD. Additional data will be available at the time of presentation.

Conclusions: JDQ443 demonstrates an acceptable safety and tolerability profile, with early signs of clinical activity in pts with NSCLC. Enrollment is ongoing to NSCLC and CRC dose-expansion groups for JDQ443 monotherapy at the RD, and to JDQ443 + TNO155 dose escalation.

Citation Format: Daniel S. Tan, Toshio Shimizu, Benjamin Solomon, Rebecca S. Heist, Martin Schuler, Maria J. De Miguel Luken, Anas Gazzah, Martin Wermke, Christophe Dooms, Herbert H. Loong, Neeltje Steeghs, Enriqueta Felip, Conor E. Steuer, Eric van Cutsem, Ross A. Soo, Ashley C. Jaeger, Jaeyeon Kim, Kun Xu, Xueying Chen, Xiaoming Cui, Heather Burks, Anna Farago, Philippe A. Cassier. KontRASt-01: A phase Ib/II, dose-escalation study of JDQ443 in patients (pts) with advanced, KRAS G12C-mutated solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT033.

A WIN Consortium phase I study exploring avelumab, palbociclib, and axitinib in advanced non-small cell lung cancer

Background

The Worldwide Innovative Network (WIN) Consortium has developed the Simplified Interventional Mapping System (SIMS) to better define the cancer molecular milieu based on genomics/transcriptomics from tumor and analogous normal tissue biopsies. SPRING is the first trial to assess a SIMS‐based tri‐therapy regimen in advanced non‐small cell lung cancer (NSCLC).

Methods

Patients with advanced NSCLC (no EGFR, ALK, or ROS1 alterations; PD‐L1 unrestricted; ≤2 prior therapy lines) received avelumab, axitinib, and palbociclib (3 + 3 dose escalation design).

Results

Fifteen patients were treated (five centers, four countries): six at each of dose levels 1 (DL1) and DL2; three at DL3. The most common ≥Grade 3 adverse events were neutropenia, hypertension, and fatigue. The recommended Phase II dose (RP2D) was DL1: avelumab 10 mg/kg IV q2weeks, axitinib 3 mg po bid, and palbociclib 75 mg po daily (7 days off/21 days on). Four patients (27%) achieved a partial response (PR) (progression‐free survival [PFS]: 14, 24, 25 and 144+ weeks), including two after progression on pembrolizumab. Four patients attained stable disease (SD) that lasted ≥24 weeks: 24, 27, 29, and 64 weeks. At DL1 (RP2D), four of six patients (66%) achieved stable disease (SD) ≥6 months/PR (2 each). Responders included patients with no detectable PD‐L1 expression and low tumor mutational burden.

Conclusions

Overall, eight of 15 patients (53%) achieved clinical benefit (SD ≥ 24 weeks/PR) on the avelumab, axitinib, and palbociclib combination. This triplet showed antitumor activity in NSCLC, including in tumors post‐pembrolizumab progression, and was active at the RP2D, which was well tolerated.

NCT03386929 clinicaltrial.gov

Pitfalls and progress in adrenocortical carcinoma diagnosis: the utility of a multidisciplinary approach, immunohistochemistry and genomics

SUMMARY

Adrenocortical carcinoma is a rare disease with poor prognosis whose clinical heterogeneity can at times present a challenge to accurate and timely diagnosis. We present the case of a patient who presented with extensive pulmonary lesions, mediastinal and hilar lymphadenopathy and an adrenal mass in whom the oncological diagnosis was initially uncertain. Through the use of immunohistochemistry, biochemistry and genomic testing, an accurate diagnosis of adrenocortical carcinoma was ultimately made which resulted in more directed treatment being administered. The use of multidisciplinary input and genomics to aid in diagnosis and prognosis of adrenocortical carcinoma is discussed.

LEARNING POINTS

Adrenocortical carcinomas can present a diagnostic challenge to clinicians given it is a rare malignancy with significant clinical heterogeneity. Specialist multidisciplinary team input is vital in the diagnosis and management of adrenocortical carcinomas. Hormonal testing is recommended in the diagnostic workup of adrenal masses, even in the absence of overt clinical signs/symptoms of hormone excess. Immunostaining for the highly sensitive and specific steroidogenic factor-1 is vital for accurate diagnosis. Genomics can provide prognostic utility in management of adrenocortical carcinoma.

Efficacy and Safety of Larotrectinib in Patients With Tropomyosin Receptor Kinase Fusion-Positive Lung Cancers

PURPOSE

Larotrectinib is a highly selective and CNS-active tropomyosin receptor kinase (TRK) inhibitor that has demonstrated efficacy across TRK fusion-positive cancers, regardless of the tumor type. The aim of this study was to assess the efficacy and safety of larotrectinib in patients with TRK fusion-positive lung cancers.

MATERIALS AND METHODS

Data from two global, multicenter, registrational clinical trials of patients treated with larotrectinib were analyzed: a phase II adult and young adult basket trial (NCT02576431) and a phase I adult trial (NCT02122913). The primary end point was objective response rate (ORR).

RESULTS

By July 20, 2020, 20 patients with TRK fusion-positive lung cancer had been treated. The ORR by investigator assessment among 15 evaluable patients was 73% (95% CI, 45 to 92); one (7%) patient had a complete response, 10 (67%) had a partial response, three (20%) had stable disease, and one (7%) had progressive disease as best response. The median duration of response, progression-free survival, and overall survival were 33.9 months (95% CI, 5.6 to 33.9), 35.4 months (95% CI, 5.3 to 35.4), and 40.7 months (95% CI, 17.2 to not estimable), respectively. Among patients with baseline CNS metastases, the ORR was 63% (95% CI, 25 to 91). Adverse events were mainly grade 1 or 2.

CONCLUSION

Larotrectinib is highly active with rapid and durable responses, extended survival benefit, and a favorable long-term safety profile in patients with advanced lung cancer harboring NTRK gene fusions, including those with CNS metastases. These findings support routine testing for NTRK fusions in patients with lung cancer.

Abstract LBA038: KontRASt: A Phase Ib/II, open-label, multi-center, dose-escalation study of JDQ443 in patients with advanced solid tumors harboring the KRAS G12C mutation

Background Kirsten rat sarcoma virus (KRAS) is a GTPase that regulates cell signaling pathways involved in cell proliferation, survival, and tumorigenesis. Somatic mutations in KRAS resulting in a glycine to cysteine substitution at codon 12 (KRAS G12C) lead to a shift toward active, GTP-bound KRAS and increased oncogenic signaling. KRAS G12C mutations occur in approximately 13% of non-squamous, non-small cell lung cancer (NSCLC) cases, and at lower frequencies in other solid tumor malignancies. JDQ443 (NVP-JDQ443) is a selective, covalent, and orally bioavailable investigational KRASG12C inhibitor that binds under the switch II loop, and irreversibly traps KRASG12C in a GDP-bound, inactive state. In preclinical models, JDQ443 potently inhibited KRASG12C cellular signaling and proliferation in a mutant-selective manner and demonstrated dose-dependent anti-tumor activity. In patients with KRAS G12C-mutated solid tumors, JDQ443 may have clinically significant antitumor activity alone and in combination with TNO155, an investigational, SHP2 inhibitor, and in combination with PD-1 blockade. Methods This is a Phase Ib/II, open-label, dose-escalation study with four arms: (A) JDQ443 monotherapy; (B) JDQ443 + TNO155; (C) JDQ443 + anti–PD-1; and (D) JDQ443 + TNO155 + anti–PD-1. Each arm has a dose-escalation portion followed by dose expansion at the maximum tolerated dose (MTD) and/or recommended dose (RD). The escalations are conducted in adult patients with advanced KRAS G12C-mutated solid tumors who have previously received standard-of-care therapies. Dose escalation is guided by an adaptive Bayesian hierarchical logistic regression model following the escalation with overdose control principle. Expansions are planned for patients with advanced (metastatic or unresectable), KRAS G12C-mutated NSCLC who have received prior immune checkpoint inhibitor therapy and platinum-based chemotherapy, and for patients with advanced, KRAS G12C-mutated colorectal cancer who have received prior fluoropyrimidine-, oxaliplatin-, and irinotecan-based chemotherapy. The primary objectives of dose escalation are to assess the safety and tolerability of JDQ443 alone and in combinations, and to identify the MTD and/or the RD, and regimens for future studies. The primary objective of dose expansion is to evaluate the antitumor activity via overall response rates for JDQ443, both alone and in combinations, in selected populations. Secondary objectives for both escalation and expansion are to evaluate the antitumor activity and characterize the pharmacokinetics of JDQ443 alone and in combinations, and to assess the immunogenicity of anti–PD-1 in combination with JDQ443 or TNO155. Safety and tolerability will also be further assessed during dose expansion. The study is currently enrolling to the dose-escalation portions of Arm A (JDQ443 monotherapy) and Arm B (JDQ443 + TNO155). NCT04699188

Citation Format: Benjamin Solomon, Rebecca S Heist, Daniel SW Tan, Philippe A Cassier, Christophe Dooms, Eric Van Cutsem, Conor E Steuer, Neeltje Steeghs, Martin Schuler, Anas Gazzah, Martin Wermke, Enriqueta Felip, Herbert HF Loong, Maria J De Miguel Luken, Ross A Soo, Ashley Jaeger, Kun Xu, Xueying Chen, Xiaoming Cui, Heather Burks, Anna F Farago, Toshio Shimizu. KontRASt: A Phase Ib/II, open-label, multi-center, dose-escalation study of JDQ443 in patients with advanced solid tumors harboring the KRAS G12C mutation [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr LBA038.

Clinical definition of acquired resistance to immunotherapy in patients with metastatic non-small-cell lung cancer

Acquired resistance (AR) to programmed cell death protein 1/programmed death-ligand 1 [PD-(L)1] blockade is frequent in non-small-cell lung cancer (NSCLC), occurring in a majority of initial responders. Patients with AR may have unique properties of persistent antitumor immunity that could be re-harnessed by investigational immunotherapies. The absence of a consistent clinical definition of AR to PD-(L)1 blockade and lack of uniform criteria for ensuing enrollment in clinical trials remains a major barrier to progress; such clinical definitions have advanced biologic and therapeutic discovery. We examine the considerations and potential controversies in developing a patient-level definition of AR in NSCLC treated with PD-(L)1 blockade. Taking into account the specifics of NSCLC biology and corresponding treatment strategies, we propose a practical, clinical definition of AR to PD-(L)1 blockade for use in clinical reports and prospective clinical trials. Patients should meet the following criteria: received treatment that includes PD-(L)1 blockade; experienced objective response on PD-(L)1 blockade (inclusion of a subset of stable disease will require future investigation); have progressive disease occurring within 6 months of last anti-PD-(L)1 antibody treatment or rechallenge with anti-PD-(L)1 antibody in patients not exposed to anti-PD-(L)1 in 6 months.

Abstract P224: Update from the Phase 2 registrational trial of repotrectinib in TKI-pretreated patients with ROS1+ advanced non-small cell lung cancer and with NTRK+ advanced solid tumors (TRIDENT-1)

Background: Repotrectinib is a next-generation ROS1/TRK tyrosine kinase inhibitor (TKI) that is currently in a registrational Phase 2 trial (TRIDENT-1). A previous update from the TRIDENT-1 trial showed a generally well tolerated safety profile in 185 treated patients. Interim efficacy data were previously presented. In ROS1+ NSCLC patients with 1 prior TKI and prior platinum-based chemotherapy (EXP-2), confirmed overall response rate (cORR) was 40% (2 of 5 patients); in ROS1+ NSCLC patients with 1 prior TKI without prior platinum-based chemotherapy (EXP-4), cORR was 67% (4 of 6 patients); in ROS1+ NSCLC patients with 2 prior TKIs without prior platinum-based chemotherapy (EXP-3), cORR was 40% (2 of 5 patients). In NTRK+ TKI-pretreated advanced solid tumor patients (EXP-6), cORR was 50% (3 of 6 patients). In addition, efficacy was demonstrated in patients who developed solvent front mutations (SFM) following prior ROS1/TRK TKI treatment. cORR was 67% (4 of 6 patients) and 50% (2 of 4 patients) in ROS1+ NSCLC and NTRK+ solid tumors patients with SFMs, respectively. One patient who developed a SFM after entrectinib treatment (EXP-2) had a cCR with 5.6+ months duration of response. Methods: TRIDENT-1 (NCT03093116) is an ongoing registrational Phase 2 trial enrolling patients whose cancers harbor a ROS1 or NTRK gene fusion. Patients are enrolled into 6 defined expansion cohorts (EXP 1-6), based on cancer type and prior therapy. The primary endpoint is cORR by Blinded Independent Central Review using RECIST v1.1. Results: An updated safety analysis across Phase 1 and Phase 2 patients (n=243) based on a data cut-off date of 4 May 2021 was conducted. Treatment-emergent adverse events (TEAEs) observed in ≥20% of patients were dizziness (62%), dysgeusia (43%), constipation (33%), dyspnea (30%), paresthesia (28%), anemia (26%), and fatigue (26%). Grade ≥3 treatment-related AEs (TRAEs) were observed in 17% of patients; no Grade 5 TRAEs were observed. The majority (77%) of dizziness TEAEs were Grade 1 and 4% were Grade 3; none of the dizziness events led to treatment discontinuation. Dose modifications remained infrequent including 24% of patients with a TEAE that led to a dose reduction and 10% of patients with a TEAE that led to drug discontinuation. Updated efficacy information for TKI-pretreated ROS1+ NSCLC and NTRK+ advanced solid tumor patients is being collected and will be available for presentation. Conclusions: Repotrectinib is a next-generation ROS1/TRK inhibitor. In an ongoing registrational Phase 2 trial, repotrectinib was generally well tolerated with low frequency of dose modifications. Updated Phase 2 efficacy data will be available for presentation.

Citation Format: Jessica J. Lin, Byoung Chul Cho, Christoph Springfeld, D. Ross Camidge, Benjamin Solomon, Christina Baik, Vamsidhar Velcheti, Young-Chul Kim, Victor Moreno, Anthonie J. van der Wekken, Enriqueta Felip, Dipesh Uprety, Denise Trone, Shanna Stopatschinskaja, Alexander Drilon. Update from the Phase 2 registrational trial of repotrectinib in TKI-pretreated patients with ROS1+ advanced non-small cell lung cancer and with NTRK+ advanced solid tumors (TRIDENT-1) [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P224.

Molecular Characteristics of Repotrectinib That Enable Potent Inhibition of TRK Fusion Proteins and Resistant Mutations

NTRK chromosomal rearrangements yield oncogenic TRK fusion proteins that are sensitive to TRK inhibitors (larotrectinib and entrectinib) but often mutate, limiting the durability of response for NTRK ⁺ patients. Next-generation inhibitors with compact macrocyclic structures (repotrectinib and selitrectinib) were designed to avoid resistance mutations. Head-to-head potency comparisons of TRK inhibitors and molecular characterization of binding interactions are incomplete, obscuring a detailed understanding of how molecular characteristics translate to potency. Larotrectinib, entrectinib, selitrectinib, and repotrectinib were characterized using cellular models of wild-type TRKA/B/C fusions and resistance mutant variants with a subset evaluated in xenograft tumor models. Crystal structures were determined for repotrectinib bound to TRKA (wild-type, solvent-front mutant). TKI-naïve and pretreated case studies are presented. Repotrectinib was the most potent inhibitor of wild-type TRKA/B/C fusions and was more potent than selitrectinib against all tested resistance mutations, underscoring the importance of distinct features of the macrocycle structures. Cocrystal structures of repotrectinib with wild-type TRKA and the TRKA^G595R SFM variant elucidated how differences in macrocyclic inhibitor structure, binding orientation, and conformational flexibility affect potency and mutant selectivity. The SFM crystal structure revealed an unexpected intramolecular arginine sidechain interaction. Repotrectinib caused tumor regression in LMNA-NTRK1 xenograft models harboring GKM, SFM, xDFG, and GKM + SFM compound mutations. Durable responses were observed in TKI-naïve and -pretreated patients with NTRK ⁺ cancers treated with repotrectinib (NCT03093116). This comprehensive analysis of first- and second-generation TRK inhibitors informs the clinical utility, structural determinants of inhibitor potency, and design of new generations of macrocyclic inhibitors.

Abstract P02-01: Repotrectinib in patients with NTRK fusion-positive advanced solid tumors: update from the registrational phase 2 TRIDENT-1 trial

Background: NTRK fusions drive a broad range of solid tumors. Two FDA approved TRK tyrosine kinase inhibitors (TKIs) have demonstrated efficacy in patients (pts) with NTRK fusion+ advanced solid tumors; however, emergent TRK solvent front (SF) and gatekeeper resistance mutations occur. Repotrectinib is a next-generation ROS1/TRK TKI with potency against wildtype and mutant forms of ROS1 and TRK. In preclinical studies, repotrectinib was more potent than larotrectinib, entrectinib, and selitrectinib against wildtype TRK, SF and gatekeeper mutations. Early interim data from the Phase 1/2 TRIDENT-1 trial led to Fast Track designation by the FDA for repotrectinib in TRK TKI-pretreated pts. This abstract is an updated analysis of this population and the first presentation of repotrectinib activity in TRK TKI-naïve pts. Methods: Pts with NTRK fusion+ advanced solid tumors were enrolled into the ongoing registrational Phase 2 TRIDENT-1 trial (NCT03093116). Pts with no prior TRK TKIs were enrolled into Expansion Cohort 5 (EXP-5) and pts who received up to 2 lines of prior TRK TKIs were enrolled into EXP-6. Prior chemotherapy and/or immunotherapy were allowed in both cohorts. The primary endpoint is cORR by Blinded Independent Central Review using RECIST v1.1. Results: As of efficacy data cutoff date of 28 July 2021, 8 pts in EXP-5 and 19 pts in EXP-6 had at least 2 post-baseline scans and were evaluable for efficacy analysis. Median age was 63 y (range 33–80) in EXP-5 and 50 y (range 23–81) in EXP-6; median number of prior lines of chemo/immunotherapy was 1 (range 0–2) in EXP-5 and 1 (range 0–4) in EXP-6. In EXP-6, 79% (15/19) of pts received 1 prior TRK TKI. Confirmed responses were reported by physician assessment. In EXP-5, cORR was 63% (5 of 8 pts; 95% CI: 24–91%) with DOR from 1.9+ to 7.4+ months (mo). In EXP-6, cORR was 47% (9 of 19 pts; 95% CI: 24–71%) with DOR from 1.9+ to 15.1 mo. In 10 pts enrolled in EXP-6 with a SF mutation, the cORR was 60% (6 of 10 pts; 95% CI: 26–88%). Median duration of treatment was 6.3 mo (range 0.9–13.4+) in EXP-5 and 8.1 mo (range 1.1–20.8) in EXP-6. An updated safety analysis for Phase 1 and Phase 2 (n=243) based on a data cut-off date of 4 May 2021 was conducted. Repotrectinib was generally well tolerated. Treatment-emergent adverse events (TEAEs) observed in ≥20% of patients were dizziness (62%), dysgeusia (43%), constipation (33%), dyspnea (30%), paresthesia (28%), anemia (26%), and fatigue (26%). The majority (77%) of dizziness TEAEs were Grade 1 and 4% were Grade 3; none of the dizziness events led to treatment discontinuation. Dose modifications remained infrequent (24% of pts had a dose reduction and 10% of pts discontinued study drug due to a TEAE). Conclusions: Repotrectinib is a next-generation ROS1 and TRK inhibitor. In an ongoing registrational Phase 2 trial, repotrectinib demonstrated efficacy in TRK TKI-naïve and TKI-pretreated pts and was generally well tolerated. Enrollment in the multi-cohort Phase 2 trial is ongoing.

Citation Format: Benjamin Besse, Christina Baik, Christoph Springfeld, Alice Hervieu, Victor Moreno, Lyudmila Bazhenova, Jessica J. Lin, D. Ross Camidge, Benjamin Solomon, Vamsidhar Velcheti, Anthonie J. van der Wekken, Enriqueta Felip, Dipesh Uprety, Denise Trone, Shanna Stopatschinskaja, Byoung Chul Cho, Alexander Drilon. Repotrectinib in patients with NTRK fusion-positive advanced solid tumors: update from the registrational phase 2 TRIDENT-1 trial [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P02-01.

Custom workflows to improve joint variant calling from multiple related tumour samples: FreeBayesSomatic and Strelka2Pass

SUMMARY

This work describes two novel workflows for variant calling that extend the widely used algorithms of Strelka2 and FreeBayes to call somatic mutations from multiple related tumour samples and one matched normal sample. We show that these workflows offer higher precision and recall than their single tumour-normal pair equivalents in both simulated and clinical sequencing data.

AVAILABILITY AND IMPLEMENTATION

Source code freely available at the following link: https://atlassian.petermac.org.au/bitbucket/projects/DAW/repos/multisamplevariantcalling and executable through Janis (https://github.com/PMCC-BioinformaticsCore/janis) under the GPLv3 licence.

SUPPLEMENTARY INFORMATION

Supplementary data are available at Bioinformatics online.

Functional and patient-reported changes in swallowing and voice after combined chemotherapy and radiotherapy for limited-stage small-cell lung cancer

INTRODUCTION

The purpose of this study was to describe the nature and impact of dysphagia and dysphonia in patients with limited-stage small-cell lung cancer (SCLC) before and after chemoradiation.

METHODS

A prospective cohort study was conducted on patients receiving chemoradiotherapy for limited-stage SCLC. Patients received either 40, 45 or 50 Gy, commencing the second cycle of chemotherapy. Outcomes included: videofluoroscopy (VFSS) to investigate aspiration, swallowing function and oesophageal motility; oral intake limitations; patient-reported dysphagia; and patient-reported dysphonia. Data were collected before treatment and one, three and six months post-treatment.

RESULTS

Twelve patients were enrolled. Oropharyngeal swallowing was safe and functional at all times. Three patients exhibited oesophageal motility disorders before treatment, and a further three post-treatment. Oral intake was most compromised one month post-treatment with five patients either tube dependent or eating very limited diets. At all other times patients were eating normal or near-normal diets. Despite normal oropharyngeal swallowing on VFSS, three patients reported moderate or severe dysphagia one month post-treatment. Three additional patients reported moderate or severe difficulties three and six months post-treatment. Patients who reported dysphagia one month post-treatment all received a mean and maximum oesophageal dose of ≥15.7 Gy and ≥42 Gy, respectively. Dose-response relationships were not apparent three and six months post-treatment. Voice problems varied, with worst scores reported one month post-treatment.

CONCLUSIONS

This study identified discordance between observed swallowing function and patient-reported problems, which has clinical implications for patient management, and highlights future research needs. Ongoing efforts to reduce mucosal toxicity in patients with lung cancer are essential.