An assessment of extended pembrolizumab dosing in advanced non-small-cell lung cancer in the COVID-19 pandemic

Background: There are limited clinical data comparing extended dosing (ED) versus standard dosing (SD) of pembrolizumab for metastatic non-small-cell lung cancer. Methods: This retrospective study included patients with metastatic non-small-cell lung cancer and PD-L1 tumor proportion score ≥50% treated with one or more cycles of single-agent pembrolizumab with SD or ED from January 2018 to December 2020. Results: A higher proportion of patients were alive in the ED group (vs SD) at 6 months (94 vs 51%), 12 months (94 vs 33%) and data cutoff (94 vs 26%) (p < 0.001 for all). The rate (44 vs 32%; p = 0.407) and severity of grade ≥3 immune-related adverse events were similar (50 vs 52%); however, ED patients more frequently discontinued treatment due to toxicity (45 vs 15%; p < 0.001). Conclusion: A greater proportion of ED patients were alive at data cutoff, and the rate and severity of immune-related adverse events were similar between groups.

Prospective Evaluation of Fetal Hemoglobin Expression in Maternal Erythrocytes: An Analysis of a Cohort of 345 Parturients

It is believed that fetal hemoglobin (HbF) expression in adults is largely genetically regulated. The increased expression of HbF in pregnancy has been reported in a small number of articles. Different mechanisms have been proposed, but the description of HbF expression during pregnancy remains unclear. The objectives of this study were to document HbF expression during peri and postpartum periods, confirm its maternal origin, and assess clinical and biochemical parameters potentially associated with HbF modulation. In this observational prospective study, 345 pregnant women were followed. At baseline, 169 had HbF expression (≥1% of total hemoglobin) and 176 did not have HbF expression. Women were followed at the obstetric clinic during their pregnancy. Clinical and biochemical parameters were measured at each visit. Analyses were made to determine which parameters had a significant correlation to HbF expression. Results show that HbF expression of ≥1% during peri and postpartum periods in pregnant women without influencing comorbidities is at its highest peak during the first trimester. In all women, it was proven that HbF was of maternal origin. A significant positive correlation between HbF expression, βeta-human chorionic gonadotropin (β-HCG), and glycosylated hemoglobin (HbA1c) was present. A significant negative association between HbF expression and total hemoglobin was found. HbF expression induction during pregnancy is probably associated with an increase in β-HCG and HbA1C, and a decrease in total hemoglobin, which could temporarily reactivate the fetal erythropoietic system.

Abstract P3-07-10: CCTG IND.236: A Phase 1b trial of combined CFI-402257 and weekly paclitaxel in patients with HER2-negative (HER2-) advanced breast cancer (aBC)

CCTG IND.236: A Phase 1b trial of combined CFI-402257 and weekly paclitaxel in patients with HER2-negative (HER2-) advanced breast cancer (aBC) Philippe L. Bedard, Mihaela Mates, John Hilton, Nathalie Levasseur, Arif Awan, Amirrtha Srikanthan, David Cescon, Karen Gelmon, Andrew Robinson, Nancy Drummond-Ivars, Irene Li, Laleh Rastgou, Jackie Edwards, Linda Hagerman, Siwei Zhang, Mark Bray, Lesley Seymour, Moira Rushton-Marovac, Pierre-Olivier Gaudreau Background: CFI-402257 is a selective oral inhibitor of TTK protein kinase, a critical regulator of the mitotic spindle assembly checkpoint overexpressed in breast cancer (BC). CFI-402257 monotherapy has anti-proliferative and cytotoxic activity and enhances antitumor activity of paclitaxel in BC xenograft models. Material and methods: Primary objectives were to establish safety and Recommended Phase 2 dose (RP2D) of CFI-402257 combined with weekly paclitaxel (Phase 1b) and Overall Response Rate (ORR) as per RECIST 1.1 (Phase 2). Patients with HER2- aBC with adequate organ function, PS 0-1, previously treated with &gt;1 non-taxane chemotherapy, were eligible. A 3+3 design was used for Phase 1b, with dose limiting toxicities (DLTs) assessed during cycle 1 (28 days). Starting dose CFI-402257 was 84mg (DL1 = 84mg, DL2 = 112mg, DL3 = 168mg, DL4 = 210mg and DL5 = 252mg) on a 2-day on, 5-day off schedule with paclitaxel 80mg/m2 day 1, 8, 15. Safety assessments were performed weekly (CTCAE v5.0) and response every 2 cycles. A Simon 2-stage design was used for Phase 2 (stage 2 required ≥4 responses in 17 evaluable patients from stage 1). Results: 37 patients received a total of 260 cycles including all 5 dose levels. Median age was 59; 92% ER+/HER2-; 49% PS1; 22% 3 prior chemotherapy lines; 41% 4 sites of metastatic disease, and 81% had received prior CDK4/6 inhibitors. Grade 3 hematological adverse events (AEs, all dose levels) were neutropenia (70%), lymphopenia (41%) and anemia (14%). Six DLTs occurred: 5 dose-related grade 4 neutropenia and 1 febrile neutropenia. Three DLTs occurred at DL3, two at DL4, and one at DL5. Three serious AEs (two at DL3, and one at DL4) at least possibly related to treatment were seen: 2 febrile neutropenia and 1 skin infection (all grade 3). Frequent AEs (˃5%; all dose levels) considered at least possibly related to treatment were: diarrhea (38%), nausea (30%), fatigue (27%), vomiting (16%), anorexia (14%), maculo-papular rash (14%), oral mucositis (11%), alopecia (11%) and pruritus (8%). DL3 (168mg) was selected as RP2D. ORR was 3/36=8% and 1/17=5.9% in all vs Phase 2 evaluable patients, respectively. Clinical Benefit Rate (CBR; defined as complete response, partial response or stable disease ˃16 weeks in duration) was 18/33=54.6% and 10/17=58.8% in all vs Phase 2 evaluable patients, respectively. During Phase 2, the 17 evaluable patients from stage 1 did not meet pre-specified threshold for anti-tumor activity to proceed to stage 2. Conclusions: CFI-402257 and paclitaxel was well tolerated, with neutropenia as the main toxicity. DL3 (168mg) was selected as RP2D. Phase 2 ORR and CBR was 5.9% and 58.8%, respectively; during Phase 2, the 17 evaluable patients from stage 1 did not meet the pre-specified threshold for anti-tumor activity to proceed to stage 2 and the trial was closed to accrual on April 7, 2022. Final analysis and correlative analyses are ongoing. Acknowledgements: Coordinated by the CCTG. Funding supported by SU2C Canada - Canadian Cancer Society Breast Cancer Dream Team Research Funding (SU2C-AACR-DT-18-15) and OICR. CFI-402257 provided by Treadwell Therapeutics.

Citation Format: Philippe Bedard, Mihaela Mates, John Hilton, Nathalie Levasseur, Arif Awan, Amirrtha Srikanthan, David W. Cescon, Karen Gelmon, Andrew Robinson, Nancy Drummond-Ivars, Irene Li, Laleh Rastgou, Jackie Edwards, Linda Hagerman, Siwei Zhang, Mark Bray, Lesley Seymour, Moira Rushton, Pierre-Olivier Gaudreau. CCTG IND.236: A Phase 1b trial of combined CFI-402257 and weekly paclitaxel in patients with HER2-negative (HER2-) advanced breast cancer (aBC) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-07-10.

Abstract P3-07-14: A phase II study of CFI-400945 in patients with advanced/metastatic cancer: Canadian Cancer Trials Group (CCTG) IND.237

Background:

CFI-400945 is a selective oral inhibitor of Polo-like Kinase 4 (PLK4), a controller of centriole duplication and mitotic progression identified by functional screening of genomically unstable breast cancer (BC). IND.237 (NCT01954316) is an open label, multicentre, phase 2 study in HER2 negative metastatic breast cancer (MBC) with 3 cohorts, 1 enriched for PTEN loss of function. Enrollment started in 2018 at 64mg based on a previously established recommended phase 2 dose (RP2D). The initial patients had higher than expected grade 3/4 neutropenia which led to a voluntary hold and dose de-escalation; the new RP2D was declared at 32mg as previously reported Here we report the results of the phase 2 study of CFI-400945 in advanced BC patients.

Materials and Methods:

49 patients were enrolled across 3 cohorts: 1: triple negative; 2: ER+/HER2- PTEN low (by IHC); 3: ER+/HER2-, PTEN intact. The primary outcome is objective response rate (ORR); secondary outcomes included disease control rate (DCR) &gt;16w, and safety. A Simon 2-stage design was used (9 – 25 pts planned for each cohort). CFI-400945 would be considered active if ≥3 responses were observed in any given cohort. Eligibility included ECOG 0-1, adequate organ function and receipt of at ≥1 prior line of cytotoxic chemotherapy in any setting including anthracycline taxane (unless contraindicated). Treatment was 32mg 7d on 7d off in cycle 1 (cycle length=28d), then continuously starting cycle 2. Safety assessments were performed each cycle and response (RECIST 1.1) every 2 cycles.

Results:

60 patients have been screened, 49 enrolled: 10 were in initial dose ranging and were excluded from phase 2 response assessment. 10 patients were enrolled in cohort 1, 4 in cohort 2, and 25 in cohort 3. Table 1 presents patient characteristics and response results. 1 patient in cohort 3 has not had disease re-assessed at time of abstract submission. The most common adverse events have been cytopenias, nausea, fatigue, headache, constipation and vomiting. Less than 5% of patients experienced a non-hematologic AE &gt; grade 3; 33% experienced ≥ grade 3 neutropenia.

Conclusions:

CFI-400945 32mg is well tolerated in this MBC population with moderate incidence of uncomplicated neutropenia. The TNBC cohort so this arm has been closed to further accrual for lack of responses. The PTEN loss group has been slow to accrue and remains open. Responses in the ER+/HER2- arm are encouraging – results from patients remaining on study are awaited and correlative studies to identify features associated with responses are underway.

Acknowledgements: Sponsored by the Canadian Cancer Trials Group. Supported by Stand Up To Cancer Canada (scientific partner AACR) Canadian Cancer Society (CCS) Breast Cancer Dream Team Research Funding, Ontario Institute for Cancer Research (funding provided by the Government of Ontario) and grants from CCS to CCTG.

Table 1. Table 1. Patient characteristics and response rates in each cohort treated with CFI-400945.

Citation Format: David W. Cescon, John Hilton, Philippe Bedard, Phillip Blanchette, Rossanna C. Pezo, Ayesha Bashir, Vikaash Kumar, Terry L. Ng, Arif Awan, Anthony Lott, Jacques Antoun Raphael, Linda Hagerman, Mark Bray, Lindsay Muyot, Jesus Fuentes Antras, Lesley Seymour, Dongsheng Tu, Pierre-Olivier Gaudreau, Moira Rushton. A phase II study of CFI-400945 in patients with advanced/metastatic cancer: Canadian Cancer Trials Group (CCTG) IND.237 [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-07-14.

Abstract P3-07-18: CCTG IND.239: A phase 2 study of combined CFI-400945 and durvalumab in patients with advanced triple negative breast cancer (aTNBC)

CCTG IND.239: A phase 2 study of combined CFI-400945 and durvalumab in patients with advanced triple negative breast cancer (aTNBC) John Hilton, David W. Cescon, Andrew Robinson, Sukhbinder Dhesy-Thind, Sara Kristina Taylor, Arif Awan, Terry Ng, Moira Rushton, Marie-France Savard, Lindsay Muyot, Marie Claude Reeves, Linda Hagerman, Hongbo Lui, Mark Bray, Dongsheng Tu, Lesley Seymour, Pierre-Olivier Gaudreau Background: CFI-400945 is a selective oral inhibitor of Polo-like Kinase 4 (PLK4), which controls centriole duplication and mitotic progression, and was identified as a drug target based on functional screening of genomically unstable breast cancers. CFI-400945 monotherapy has anti-proliferative activity and enhances antitumor activity when combined with anti-PD-1 immune checkpoint blockade in transplantable murine cancer models. Material and methods: In this multi-centre phase II trial of CFI-400945 and durvalumab combination therapy, the primary objective was overall response rate (ORR) per RECIST 1.1. Patients with aTNBC with adequate organ function, PS 0-1, previously treated with &gt;1 line of chemotherapy including anthracycline and/or taxane, were eligible. CFI-400945 32mg monotherapy was administered on a 7-day on, 7-day off schedule for cycle 1 (which reduced the likelihood of significant hematologic toxicity). From cycle 2 onwards, CFI-400945 32mg daily was administered in combination with durvalumab 1500mg IV every 28 days; responses were assessed every 8 weeks. Following trial activation, 3 patients received a CFI-400945 dose of 40mg (same schedule) for a total of 9 cycles before 32mg was declared as the new recommended phase 2 dose (based on other ongoing trials using CFI-400945). A Simon 2-stage design was used; ≥3/15 responses in stage 1 were required to expand to stage 2. Exploratory PD-L1 expression was measured on immune and tumor cells using the SP263 assay. Results: 15 patients received a total of 45 cycles (1-12 cycles per patient). Median age was 56 (31-76); 53% PS1; 20% 3 prior chemotherapy lines and; 27% 4 sites of metastatic disease. Immune vs tumor cell PD-L1 expression was 1% in 50% and 23% of patients, respectively (immune and tumor cell expression was mutually exclusive). Immune vs tumor cell PD-L1 expression was 10% in 17% and 15% of patients, respectively. Grade 3 hematological adverse events (AEs) were lymphopenia (40%), neutropenia (20%), anemia and thrombocytopenia (7% for both). One serious AE at least possibly related to treatment was seen: grade 3 febrile neutropenia. Frequent AEs (˃5%) considered at least possibly related to CFI-400945 were: nausea and anorexia (both 20%), fatigue and dysgeusia (both 13%), headache, dizziness, maculo-papular rash, back pain and gastroesophageal reflux disease (all 7%), Frequent AEs (˃5%) considered at least possibly related to durvalumab were: anorexia (13%), arthritis, fatigue, back pain, pain in extremity and hot flashes (all 7%). No responses were observed in 14 evaluable patients during stage 1, therefore the pre-specified threshold for anti-tumor activity to proceed to stage 2 was not met. Disease control rate (complete response, partial response or stable disease ˃16 weeks in duration) was 7% (1/14). Conclusions: CFI-400945 and durvalumab was well tolerated, with no unexpected toxicities of the combination. However, in this heavily pretreated and PD-L1 unselected TNBC population, no responses were observed and the pre-specified threshold for anti-tumor activity for stage 2 was not met. The trial was closed to accrual on April 26, 2022. Final analysis and correlative analyses are ongoing. Acknowledgements: Coordinated by the CCTG. Funding supported by Astra Zeneca. CFI-400945 provided by Treadwell Therapeutics and durvalumab provided by Astra Zeneca.

Citation Format: John Hilton, David W. Cescon, Andrew Robinson, Sukhbinder Dhesy-Thind, Sara Taylor, Arif Awan, Terry L. Ng, Moira Rushton, Marie-France Savard, Lindsay Muyot, Marie Claude Reeves, Linda Hagerman, Hongbo Lui, Mark Bray, Dongsheng Tu, Lesley Seymour, Pierre-Olivier Gaudreau. CCTG IND.239: A phase 2 study of combined CFI-400945 and durvalumab in patients with advanced triple negative breast cancer (aTNBC) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-07-18.

Brief Report: Canadian Cancer Trials Group IND.227: A Phase 2 Randomized Study of Pembrolizumab in Patients With Advanced Malignant Pleural Mesothelioma (NCT02784171)

Immune checkpoint inhibitors have activity in mesothelioma. IND.227 was a phase 2 trial (120 patients planned) comparing progression-free survival of standard platinum and pemetrexed (CP) versus CP + pembrolizumab (pembro) versus pembro. Accrual to the pembro arm was discontinued on the basis of interim analysis (IA-16 wk disease control rate). CP + pembro was tolerable, with progression-free survival similar between arms and median survival and overall response rate higher than those of CP alone (19.8 mo [95% confidence interval or CI: 8.4-41.36] versus 8.9 mo [95% CI: 5.3-12.8] and 47% [95% CI: 24%-71%] versus 19% [95% CI: 5%-42%], respectively). The subsequent phase 3 trial has completed accrual; results are expected in 2023.

A study of the efficacy and toxicity outcomes of extended durvalumab dosing in patients with stage III unresectable non-small cell lung cancer (NSCLC) during the COVID-19 pandemic

BACKGROUND

Durvalumab following chemoradiation in unresectable stage III non-small cell lung cancer (NSCLC) has led to improved outcomes. The schedule of administration has been determined by pharmacokinetic studies. This study evaluates real-world efficacy and safety outcomes of extended dosing (ED) vs. standard dosing (SD) of durvalumab.

METHODS

Stage III NSCLC patients treated at the Cancer center of Southeastern Ontario with consolidative durvalumab from March 2017-December 2020 were included. Patient characteristics and outcomes were evaluated through retrospective review. Comparisons were made using chi-square and t-tests. Kaplan-Meier curves were used to analyze overall survival (OS).

RESULTS

A total of 35 patients were included; 15 (43%) switched to ED. Distant recurrence rates were higher in the ED group (53% vs. 20%, p = 0.07), with no differences in the sites of disease recurrence. A similar proportion of patients were alive in the ED vs. SD group (93% vs. 80%, p = 0.3), with no significant difference in OS. There were less grade 3 or greater immune-related adverse events in the ED group (0% vs. 20%). Treatment discontinuation occurred in 47% vs. 50% in the ED vs. SD groups, respectively, owing to toxicity in 20% of patients in the ED group vs. 40% in the SD group.

CONCLUSIONS

Extended dosing has similar efficacy and toxicity to standard dosing; however, there was a higher rate of toxicity necessitating discontinuation in the SD group, which may have impacted the clinical decision-making to switch to ED. Our data is limited by a small sample size and should be further validated in larger cohorts.

Optimal CCN4 Immunofluorescence for Tissue Microarray

CCN4 (also known as WNT1-Inducible Signaling Pathway Protein 1 or WISP1) is a 367 amino acid, 40 kDa protein located on chromosome 8q24.1-8q24.3. Prior studies have provided support for a pro-inflammatory role for CCN4. We have shown recently that CCN4 expression is associated with advanced disease, epithelial-mesenchymal transition, and an inflamed tumor microenvironment in multiple solid tumors. We detail here the CCN4 tissue microarray immunofluorescence protocol related to these findings.

Effect of bone metastasis on outcomes in the CCTG BR.34 phase II randomized trial of dual immune checkpoint inhibitor (ICI) treatment with or without chemotherapy in high-risk, stage IVA/B NSCLC

9067

Background: Bone metastasis (BM) occurs in about 40% of patients with metastatic lung cancer. Recently, BM was associated with decreased OS to nivolumab in previously-treated NSCLC (Landi L et al, P1.01.53, 19th WCLC, 2018). CCTG BR.34 (NCT03057106) was an open-label, randomized phase II clinical trial that randomized 301 patients with treatment-naïve, high-risk, stage IVA/B NSCLC without sensitizing EGFR or ALK alterations (1:1) to durvalumab plus tremelimumab with or without platinum doublet chemotherapy. First, 109 patients accrued with stage IVB, or selected IVA disease. Then 192 patients accrued with any stage IVA/B disease. In CCTG BR.34, median OS was not significantly different: 16.6 mo in the chemotherapy plus immunotherapy (C+IO) arm, vs 14.1 mo in the IO alone arm (HR 0.88, p = 0.46) (Leighl NB et al, J Thor Oncol, 2021). However, in BR.34 PFS was significantly longer in the C+IO arm (7.7 mo) compared to the IO alone arm (3.2 mo) (HR 0.67, 95% CI, 0.52 – 0.88). Here we analyzed the effect of BM on outcomes in BR.34. Methods: The 301 patients in the trial were characterized by the presence of BM at study entry (129-yes, 172-no). BM effect was evaluated on trial outcomes (OS, PFS, and ORR) using Cox/logistic regression analysis. Multivariable analysis was performed adjusting for the clinical and molecular covariates available. Results: In univariate analysis of the entire study population, median OS was significantly shorter for patients with BM vs those without BM (10. 9 vs 18.7 mos, HR 1.68, p = 0.001), as was median PFS (3.4 vs 7.2 mos, HR 1.82, p < 0.0001), and lower ORR (29.5% vs 45.9%, OR 0.52, p = 0.003), respectively. There was no evidence of differential association of BM with treatment arms for OS (p = 0.23), PFS (p = 0.84), and ORR (p = 0.25, Breslow-Day test). In multivariate analysis (MVA), BM remained significantly associated with worse OS (HR 1.44, p = 0.026), PFS (HR 1.69, p < 0.0001), and ORR (OR 0.52, p = 0.01). In MVA for OS: TMB, histology type, race, and ECOG were also significant; but age, smoking history, and PD-L1 IHC status were not significant. Conclusions: In CCTG BR.34 the presence of BM at trial entry was associated with significantly shorter OS, PFS, and lower ORR. BM is therefore a significant adverse prognostic factor in high-risk, stage IVA/B NSCLC treated with durvalumab and tremilimumab (with or without platinum doublet chemotherapy). If confirmed in a larger phase III trial, BM should be considered as an important new stratification factor in all clinical trials of immune checkpoint inhibitor (ICI) therapy. We and others have reported that molecules arising in the bone microenvironment (e.g: IL-8, PTHrP, TGF-b, sclerostin, and activin A) cause immunosuppression in cancer, and future trials should evaluate the addition of targeted therapies against these factors in combination with the ICIs in patients with BM.

iRECIST and atypical patterns of response to immuno-oncology drugs

With the advent of immunotherapy as one of the keystones of the treatment of our patients with cancer, a number of atypical patterns of response to these agents has been identified. These include pseudoprogression, where the tumor initially shows objective growth before decreasing in size, and hyperprogression, hypothesized to be a drug-induced acceleration of the tumor burden. Despite it being >10 years since the first immune-oncology drug was approved, neither the biology behind these paradoxical responses has been well understood, nor their incidence, identification criteria, predictive biomarkers, or clinical impact have been fully described. Immune-based Response Evaluation Criteria in Solid Tumors (iRECIST) guidelines have been published as a revision to the RECIST V.1.1 criteria for use in trials of immunotherapeutics, and the iRECIST subcommittee (of the RECIST Working Group) is working on elucidating these aspects, with data sharing a current major challenge to move forward with this unmet need in immuno-oncology.

Dietary fiber and probiotics influence the gut microbiome and melanoma immunotherapy response

Gut bacteria modulate the response to immune checkpoint blockade (ICB) treatment in cancer, but the effect of diet and supplements on this interaction is not well studied. We assessed fecal microbiota profiles, dietary habits, and commercially available probiotic supplement use in melanoma patients and performed parallel preclinical studies. Higher dietary fiber was associated with significantly improved progression-free survival in 128 patients on ICB, with the most pronounced benefit observed in patients with sufficient dietary fiber intake and no probiotic use. Findings were recapitulated in preclinical models, which demonstrated impaired treatment response to anti–programmed cell death 1 (anti–PD-1)–based therapy in mice receiving a low-fiber diet or probiotics, with a lower frequency of interferon-γ–positive cytotoxic T cells in the tumor microenvironment. Together, these data have clinical implications for patients receiving ICB for cancer.

Gut microbiota signatures are associated with toxicity to combined CTLA-4 and PD-1 blockade

Treatment with combined immune checkpoint blockade (CICB) targeting CTLA-4 and PD-1 is associated with clinical benefit across tumor types, but also a high rate of immune-related adverse events. Insights into biomarkers and mechanisms of response and toxicity to CICB are needed. To address this, we profiled the blood, tumor and gut microbiome of 77 patients with advanced melanoma treated with CICB, with a high rate of any ≥grade 3 immune-related adverse events (49%) with parallel studies in pre-clinical models. Tumor-associated immune and genomic biomarkers of response to CICB were similar to those identified for ICB monotherapy, and toxicity from CICB was associated with a more diverse peripheral T-cell repertoire. Profiling of gut microbiota demonstrated a significantly higher abundance of Bacteroides intestinalis in patients with toxicity, with upregulation of mucosal IL-1β in patient samples of colitis and in pre-clinical models. Together, these data offer potential new therapeutic angles for targeting toxicity to CICB.

Th17 cells contribute to combination MEK inhibitor and anti-PD-L1 therapy resistance in KRAS/p53 mutant lung cancers

Understanding resistance mechanisms to targeted therapies and immune checkpoint blockade in mutant KRAS lung cancers is critical to developing novel combination therapies and improving patient survival. Here, we show that MEK inhibition enhanced PD-L1 expression while PD-L1 blockade upregulated MAPK signaling in mutant KRAS lung tumors. Combined MEK inhibition with anti-PD-L1 synergistically reduced lung tumor growth and metastasis, but tumors eventually developed resistance to sustained combinatorial therapy. Multi-platform profiling revealed that resistant lung tumors have increased infiltration of Th17 cells, which secrete IL-17 and IL-22 cytokines to promote lung cancer cell invasiveness and MEK inhibitor resistance. Antibody depletion of IL-17A in combination with MEK inhibition and PD-L1 blockade markedly reduced therapy-resistance in vivo. Clinically, increased expression of Th17-associated genes in patients treated with PD-1 blockade predicted poorer overall survival and response in melanoma and predicated poorer response to anti-PD1 in NSCLC patients. Here we show a triple combinatorial therapeutic strategy to overcome resistance to combined MEK inhibitor and PD-L1 blockade.

Neoadjuvant Chemotherapy Increases Cytotoxic T Cell, Tissue Resident Memory T Cell, and B Cell Infiltration in Resectable NSCLC

INTRODUCTION

The combination of programmed cell death protein-1 or programmed death-ligand 1 immune checkpoint blockade and chemotherapy has revolutionized the treatment of advanced NSCLC, but the mechanisms underlying this synergy remain incompletely understood. In this study, we explored the relationships between neoadjuvant chemotherapy and the immune microenvironment (IME) of resectable NSCLC to identify novel mechanisms by which chemotherapy may enhance the effect of immune checkpoint blockade.

METHODS

Genomic, transcriptomic, and immune profiling data of 511 patients treated with neoadjuvant chemotherapy followed by surgery (NCT) versus upfront surgery (US) were compared with determined differential characteristics of the IMEs derived from whole-exome sequencing (NCT = 18; US = 73), RNA microarray (NCT = 45; US = 202), flow cytometry (NCT = 17; US = 39), multiplex immunofluorescence (NCT = 10; US = 72), T-cell receptor sequencing (NCT = 16 and US = 63), and circulating cytokines (NCT = 18; US = 73).

RESULTS

NCT was associated with increased infiltration of cytotoxic CD8⁺ T cells and CD20⁺ B cells. Moreover, NCT was associated with increases in CD8⁺CD103⁺ and CD4⁺CD103⁺PD-1⁺TIM3^- tissue resident memory T cells. Gene expression profiling supported memory function of CD8⁺ and CD4⁺ T cells. However, NCT did not affect T-cell receptor clonality, richness, or tumor mutational burden. Finally, NCT was associated with decreased plasma BDNF (TrkB) at baseline and week 4 after surgery.

CONCLUSIONS

Our study supports that, in the context of resectable NSCLC, neoadjuvant chemotherapy promotes antitumor immunity through T and B cell recruitment in the IME and through a phenotypic change toward cytotoxic and memory CD8⁺ and CD4⁺ memory helper T cells.

WISP1 is associated to advanced disease, EMT and an inflamed tumor microenvironment in multiple solid tumors

Background: WNT1-Inducible Signaling Pathway Protein 1 (WISP1) is implicated in prostate cancer growth and metastasis and the regulation of inflammation in diverse benign diseases. The objectives of this study were to assess the prognostic value of WISP1, its association to inflammation and its relevance as a biomarker for immune checkpoint blockade (ICB) response. Methods: Publicly available RNA-seq datasets were used to evaluate the prognostic value of WISP1 gene expression and its association with tumor-infiltrating lymphocytes, inflamed tumor microenvironment, and anti-PD-1 ICB response. A tissue microarray (TMA) including 285 radical prostatectomy specimens was used to confirm these associations in prostate cancer. The effect of recombinant WISP1 (rWISP1) on inflammatory cytokines was assessed in vitro. Results: High levels of WISP1 correlated with BCR-free survival in prostate adenocarcinoma and overall survival in primary melanoma, low-grade glioma, and kidney papillary cell carcinoma. Some effects could be accounted for by higher WISP1 expression in advanced disease. High WISP1 expression in prostate adenocarcinoma was correlated with CD8+ cells density. In vitro, rWISP1 increased inflammatory cytokine production. High WISP1 gene expression in RNA-seq datasets was correlated with gene signatures of multiple immune cell types as well as an inflammatory cytokine, immune checkpoint, and epithelial-mesenchymal transition (EMT) gene expression. WISP1 mRNA expression was associated with primary resistance to ICB in datasets showing EMT. Conclusions: Our results support an association between WISP1 expression and advanced disease, EMT and an inflamed tumor microenvironment in multiple solid tumors. The consequences of WISP1 expression on cancer immunotherapy remains to be addressed.

Immune Checkpoint Blockade across the Cancer Care Continuum

Four studies recently reported in the New England Journal of Medicine highlight advances in treatment with immune checkpoint blockade across the cancer care continuum. These findings demonstrate efficacy of these agents in the treatment of early and late-stage disease, as monotherapy or in combination, and in addition to-or in place of-standard front-line therapy.

Abstract 2654: Immunologic and prognostic correlates of WISP1 in prostate cancer

Background: Avoidance of immune destruction and tumor-promoting inflammation are equally important cancer hallmarks. In the context of prostate cancer, inflammatory markers and high levels of immune infiltrates have been associated with shorter biochemical recurrence (BCR)-free survival. WNT1 Inducible Signaling Pathway (WISP1) has been implicated in prostate cancer metastasis and the regulation of inflammation in diverse benign diseases. Thus, the objectives of this study were: 1) to assess the prognostic value of WISP1 in human prostate cancer, and 2) to determine the association of WISP1 to the inflammatory landscape specific to this disease.

Methods: A tumor microarray (TMA) was constructed with radical prostatectomy specimens of 285 prostate cancer patients. Multicolor manual immunofluorescence (IF) was performed to simultaneously detect WISP1, CD8 and cytokeratins 8 and 18. WISP1 expression levels were determined by the mean fluorescence intensity (MFI) in stromal, epithelial, cytoplasmic and nuclear (DAPI) areas in each core, and CD8+ cell density was determined for each compartment by dividing cell count by the percentage of the core occupied by the compartment. Finally, the prostate cancer TCGA dataset (n = 548) was used to validate the prognostic value of WISP1 mRNA expression, as well as its association to CD8+ lymphocytes using previously validated gene signatures (Becht et al., 2016).

Results: IF analyses of our TMA revealed that high levels of WISP1 in normal adjacent epithelium are significantly associated with shorter BCR-free survival in Kaplan-Meier (log-rank = 4.246, p = 0.039) and univariate Cox regression analyses (hazard ratio = 1.477; p = 0.042), but not in multivariate Cox regression analyses (hazard ratio = 1.381; p = 0.101). Furthermore, a significant correlation was found between WISP1 expression and CD8+ cell density. Gene expression analyses further showed that WISP1-high prostate tumors are associated with a CD8+ lymphocyte gene enrichment profile, and confirmed that patients with WISP1-high prostate tumors have reduced BCR-free survival (Wilcoxon rank, p = 0.003).

Conclusions: Overall, our results support a negative prognostic association for WISP1 as well as a proinflammatory role. WISP1 may represent a relevant target for the improvement of prostate cancer immunotherapy.

Citation Format: Pierre-Olivier Gaudreau, Sylvie Clairefond, Pierre-Luc Boulay, Pavel Chrobak, Bertrand Allard, Sandra Pommey, Fred Saad, Marian Young, John Stagg. Immunologic and prognostic correlates of WISP1 in prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2654.

Immunotherapy Comes of Age in Lung Cancer

Lung carcinoma is the leading cause of death by cancer worldwide. When possible, surgery is the best treatment strategy for patients with non-small-cell lung cancer. However, even with curative-intent therapy, most patients will develop local or systemic recurrence and, ultimately, succumb to their disease. In recent years, evidence on the role of the antitumor activity of the immune system and the understanding of tumor immunosurveillance have resulted in the emergence of immunotherapy as a promising therapeutic approach in lung cancer. The main approaches are immune checkpoint inhibition, such as blockade of the cytotoxic T-lymphocyte antigen-4 and programmed cell death-1 receptors and the programmed cell death-1 ligand, and vaccine therapy, which elicits specific antitumor immunity against relevant tumor-associated antigens. We have reviewed recently reported results from clinical trials and the possible future role of vaccine therapy and immune checkpoint inhibition in the treatment of small cell lung cancer and non-small-cell lung cancer.

The Present and Future of Biomarkers in Prostate Cancer: Proteomics, Genomics, and Immunology Advancements

Prostate cancer (PC) is the second most common form of cancer in men worldwide. Biomarkers have emerged as essential tools for treatment and assessment since the variability of disease behavior, the cost and diversity of treatments, and the related impairment of quality of life have given rise to a need for a personalized approach. High-throughput technology platforms in proteomics and genomics have accelerated the development of biomarkers. Furthermore, recent successes of several new agents in PC, including immunotherapy, have stimulated the search for predictors of response and resistance and have improved the understanding of the biological mechanisms at work. This review provides an overview of currently established biomarkers in PC, as well as a selection of the most promising biomarkers within these particular fields of development.

CD73-adenosine: a next-generation target in immuno-oncology

Cancer immunotherapy has entered in a new era with the development of first-generation immune checkpoint inhibitors targeting the PD1/PD-L1 and CTLA-4 pathways. In this context, considerable research effort is being deployed to find the next generation of cancer immunotherapeutics. The CD73-adenosine axis constitutes one of the most promising pathways in immuno-oncology. We and others have demonstrated the immunosuppressive role of CD73-adenosine in cancer and established proof-of-concept that the targeted blockade of CD73 or adenosine receptors could effectively promote anti-tumor immunity and enhance the activity of first-generation immune checkpoint blockers. With Phase I clinical trials now underway evaluating anti-CD73 or anti-A2A therapies in cancer patients, we here discuss the fundamental, preclinical and clinical findings related to the role of the CD73-adenosinergic pathway in tumor immunity.

CD73-adenosine reduces immune responses and survival in ovarian cancer patients

Multiple non-redundant immunosuppressive pathways are active within the microenvironment of cancers to avoid tumor eradication by the immune system. Our results demonstrate that the CD73-adenosine pathway is a major immunosuppressive mechanism co-opted by ovarian tumors to escape antitumor immunity. In ovarian cancer patients, high CD73 expression correlates with poor outcome and impaired CD8(+) T cell immunosurveillance.

Efficacy of topiramate, valproate, and their combination on aggression/agitation behavior in patients with psychosis

Topiramate is an antiepileptic drug, recently also used in the treatment of psychiatric diseases. Inasmuch as topiramate and valproate, which are currently used for aggressive behavior, share several pharmacological mechanisms (positive modulatory effect on the GABA activity and negative modulatory effect on glutamatergic neurotransmission), the objective of the present study was to compare the pharmacological effects of topiramate with those of valproate and their combination in patients with psychiatric disorders showing marked aggression and agitation. A retrospective, case-controlled, mirror-image study was carried out in a sample of 45 inpatients affected by schizophrenia, schizoaffective and bipolar disorder, and hospitalized in a maximum-security Canadian psychiatry hospital. Overt Aggression Scale, Agitation-Calmness Evaluation Scale, number and intensity of psychotic episodes, number of episodes of withdrawal from group activities per week, and number of therapeutic isolation per week and of strict surveillance intervention per week were evaluated before and after the treatments. Results indicate that patients treated with topiramate show a decrease in the average score of the Overt Aggression Scale, a decrease of episodes of agitation and of strict surveillance interventions. This effect was similar to the group treated with valproate or with the combination of valproate-topiramate. However, valproate therapy, but not topiramate therapy, decreased the intensity of agitation episodes measured by the Agitation-Calmness Evaluation Scale; valproate and the combination topiramate-valproate decreased the number of psychotic disorganization episodes as well. These results suggest that topiramate could be a valid medicine in the control of aggression in psychosis. Double-blind, randomized, placebo-controlled studies need to further assess this pharmacological indication.