Abstract CT568: β-2 adrenergic receptor (AR): Another immune checkpoint (IC)" A phase II clinical trial of propranolol (P) with pembrolizumab (Pem) in patients with unresectable stage III and stage IV melanoma

Background: Adrenergic stress (AS) reduces anti-tumor response by decreasing the frequency and function of CD8+ T- cells in the tumor microenvironment (TME), resulting in an increase in those with an “exhausted” phenotype.1 Additionally, AS increases the quantity and immunosuppressive phenotype of myeloid-derived suppressor cells (MDSC) in the TME.2 The data above suggests that β-2 AR acts akin to a tumorigenic IC which can be abrogated by using P, a well-known and highly cost efficient non-selective β-blocker. Synergistic activity of anti-PD-1 with P has been reported in several murine tumor models, including the B-16 OVA mouse model.3,4 A retrospective study has shown an improvement in overall survival (OS) in patients (pts) with metastatic melanoma (MM) treated concurrently with non-selective β-blocker and immunotherapy.5 This formed the basis for our phase I study of the combination of P (at dose levels; 10 mg, 20 mg BID, and 30mg BID) and pem 200 mg every 3 weeks in pts with MM. Our published phase I results found all 3 dose levels of P to be well tolerated, and an objective response was observed in 7/9 pts.6 A decrease in perceived stress score (PSS) in pts over time was observed. Intra-tumor ratio of (CD4+T cells + CD8+T-cells)/(MDSC+ Treg) >1 in the pre-treatment biopsy was predictive of treatment response. Based on the results of the phase I study, we chose P 30 mg BID as the recommended phase II dose. These results, though preliminary, strongly support our subsequent phase II clinical trial.

Methods: In this prospective, single-arm, phase II, multicenter trial, pts with unresectable stage III/IV MM and measurable disease per RECIST v1.1 will be treated with P (30 mg BID) + Pem. Pts with active CNS disease, prior therapy with PD-1/PD-L1 inhibitors, or contraindications to β-blocker are excluded. The primary objective is to evaluate the overall response rate (ORR) by immune-modified RECIST v1.1. The secondary objectives are the assessment of progression free survival and OS. A Simon two-stage design will be employed, requiring a minimum of 29 pts (17 in stage 1 and 12 in stage 2) to achieve approximately 80% power to detect a 20% increase (0.35 to 0.55) in the ORR. As an exploratory analysis, we will further report a) Baseline and on-treatment PSS and b) Chronotropic effect of P after 5-minute treadmill walk as a biomarker of response; c) Post therapy changes in the TME, with a 12 week on therapy optional biopsy d) Peripheral blood changes in T cell and MDSC subsets, and cytokines/chemokines. To date, 10 pts have been accrued on the study (NCT0384836).

Citation Format: Benjamin Switzer, Manu R. Pandey, Alexandra Valentine, Agnieszka Witkiewicz, Erik Knudsen, Kristopher Attwood, Joseph Tario, Pauline Funchain, Joseph J. Drabick, Hemn Mohammadpour, Marc S. Ernstoff, Igor Puzanov, Elizabeth A. Repasky, Shipra Gandhi. β-2 adrenergic receptor (AR): Another immune checkpoint (IC)" A phase II clinical trial of propranolol (P) with pembrolizumab (Pem) in patients with unresectable stage III and stage IV melanoma [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 CT568.

Newly updated activity results of alrizomadlin (APG-115), a novel MDM2/p53 inhibitor, plus pembrolizumab: Phase 2 study in adults and children with various solid tumors

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Background: Alrizomadlin restores TP53 function, activating p53-mediated apoptosis in tumor cells with wild-type TP53 and/or MDM2 amplification. Alrizomadlin also functions as a host immunomodulator and may restore antitumor activity in pts with cancers that progressed on PD-1/PD-L1 inhibitors. Methods: This US/Australian multicenter trial evaluated alrizomadlin, an investigational MDM2-selective, small-molecule inhibitor, combined with pembrolizumab, in pts with unresectable/metastatic melanoma that progressed on I-O drugs; pts with malignant peripheral nerve sheath tumor (MPNST), well-differentiated/dedifferentiated liposarcoma, non-small cell lung cancer (NSCLC), or solid tumors with ATM mutations that progressed on available standard therapy; or pts for whom therapy was unavailable. Eligible pts had ECOG performance status of 0-2 and, if present, stable brain metastases. Alrizomadlin 150 mg PO was administered QOD for 2 consecutive weeks, with 1 week off, and pembrolizumab 200 mg IV over 30 minutes on Day 1 of a 21-day cycle. Results: As of November 3, 2021, preliminary and interim results are reported for 130 pts in 6 cohorts: melanoma (n = 44), NSCLC (n = 26), ATM mutation (n = 18), liposarcoma (n = 17), urothelial (n = 13), and MPNST (n = 12). In the melanoma cohort, confirmed ORR by RECIST, (PR + CR) was 13% (2 CRs + 3 PRs/38 efficacy evaluable [EE] pts). In cutaneous and uveal melanoma subcohorts, confirmed ORR was 24% (2 CRs + 2 PRs/17 EE pts) and 9% (1 PR/11 EE pts), respectively. In the MPNST cohort, the clinical benefit rate, defined by confirmed ORR + SD of > 4 cycles, was 40% (4 SDs/10 EE pts). Additional confirmed PRs were reported in NSCLC, urothelial, and liposarcoma cohorts (1 each). Common treatment (alrizomadlin or pembrolizumab)-related adverse events (TRAEs; ≥ 10%) were nausea (62%), thrombocytopenia (39%), vomiting (38%), fatigue (38%), decreased appetite (29%), diarrhea (25%), neutropenia (15%), and anemia (12%). Grade 3+ TRAEs (≥ 5%) included thrombocytopenia (23%), neutropenia (10%), and anemia (7%). A total of 16 pts discontinued treatment due to AEs; 6 were treatment related, including grade 4 thrombocytopenia (n = 3), grade 2 vomiting (n = 1), grade 2 fatigue (n = 1), and grade 2 posterior reversible encephalopathy syndrome (PRES; n = 1). A total of 10 pts reported treatment-related SAEs: 1 each of abdominal pain, asthenia, colitis, febrile neutropenia, hypophysitis, peripheral edema, overdose, PRES, pulmonary embolism, pyrexia, and thrombocytopenia. Conclusions: Alrizomadlin, combined with pembrolizumab, is well tolerated and demonstrates preliminary antitumor activity in multiple tumor types and may restore antitumor effects in pts with cancer resistant or intolerant to I-O drugs. Internal study identifiers: APG-115-US-002; Keynote MK-3475-B66. Clinical trial information: NCT03611868.

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

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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.

Abstract P5-13-10: Elevated plasma IL-8 predicts for reduced outcomes in CCTG MA.38, a phase 2 randomized trial of palbociclib in ER+/HER2- metastatic breast cancer patients

Background: CCTG MA38 (NCT02630693) was a randomized phase II clinical trial that evaluated the efficacy of 2 dose schedules of palbociclib [100mg PO on continuous daily dose (CDD)] compared to 125mg PO daily for 3 weeks on/1 week off (STD) along with physician-choice of endocrine therapy in patients with ER+, HER- metastatic breast cancer (MBC) in the second-line setting. The final analysis indicated that palbociclib had comparable efficacy, safety and QOL for both treatment arms (SABCS 2018, abstr PD1-10). Our lab has reported that IL-8 was highly expressed by primary human breast cancers, and that higher pretreatment plasma IL-8 was significantly correlated with elevated bone resorption in HR+MBC patients (Kamalakar A et al. Bone 61:176-85, 2014). Most recently, our lab has reported that elevated serum IL-8 predicts for significantly reduced OS in 3 large metastatic cohorts of pancreatic (ASCO 2019, abstr 4131), prostate (ASCO 2020, abstr e17565) and breast cancer patients (ASCO 2020, abstr 1067). In this retrospective study, we investigated the prognostic value of pretreatment plasma IL-8 in CCTG MA38. Methods: 123 patients enrolled in MA38 were analyzed in this retrospective biomarker study. Serum IL-8 levels were measured using the ELLA immunoassay platform (ProteinSimple, San Jose, CA). Kaplan-Meier analysis and log-rank test were used to correlate plasma IL-8 levels with OS and progression-free survival (PFS). Results: In the total study cohort, pretreatment plasma IL-8 concentration had a median of 11.10 pg/ml, and 25% and 75% interquartiles of 7.36 and 15.00 pg/ml, respectively. In univariate analysis higher plasma IL-8 was a significant adverse biomarker for reduced PFS as a continuous variable (p = 0.01), at the median cutpoint (HR= 1.55, p=0.042), and in quartile cutpoints (HR=2.28, p=0.03, Q4 vs Q1). For OS, higher plasma IL-8 also trended significant for reduced OS at the median cutpoint (HR= 1.66, p=0.10). In multivariate analysis, higher plasma IL-8 also trended significant for reduced PFS (HR= 1.47, p=0.094). Conclusions: In the CCTG MA.38 trial, higher pre-treatment plasma IL-8 level was associated with reduced PFS, and is therefore an adverse prognostic biomarker for reduced outcome to the CDK 4/6 inhibitor palbociclib. Anti-IL-8 therapy combined with CDK 4/6 inhibitors should be evaluated in future trials to improve outcome in patients with higher circulating IL-8.

Citation Format: Hyma V Polimera, Dhirisha Bhatt, Lois E Shepherd, Karen Gelmon, Anil A Joy, Wendy R Parulekar, Monika Joshi, Suhail M Ali, Kim Leitzel, Cristina Truica, Monali Vasekar, Joseph J Drabick, Harry Menon, Neal Shah, Ashok Maddukuri, Prashanth Moku, E. Scott Halstead, Daniel McKeone, Todd M Umstead, BE Chen, Allan Lipton. Elevated plasma IL-8 predicts for reduced outcomes in CCTG MA.38, a phase 2 randomized trial of palbociclib in ER+/HER2- metastatic breast cancer patients [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P5-13-10.

Medical Service Use and Charges for Cancer Care in 2018 for Privately Insured Patients Younger Than 65 Years in the US

IMPORTANCE

Currently, there are limited published data regarding resource use and spending on cancer care in the US.

OBJECTIVE

To characterize the most frequent medical services provided and the associated spending for privately insured patients with cancer in the US.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used data from the MarketScan database for the calendar year 2018 from a sample of 27.1 million privately insured individuals, including patients with a diagnosis of the 15 most prevalent cancers, predominantly from large insurers and self-insured employers. Overall societal health care spending was estimated for each cancer type by multiplying the mean total spending per patient (estimated from MarketScan) by the number of privately insured patients living with that cancer in 2018, as reported by the National Cancer Institute's Surveillance, Epidemiology, and End Results program. Analyses were performed from February 1, 2018, to July 8, 2021.

EXPOSURES

Evaluation and management as prescribed by treating care team.

MAIN OUTCOMES AND MEASURES

Current Procedural Terminology and Healthcare Common Procedure Coding System codes based on cancer diagnosis code.

RESULTS

The estimated cost of cancer care in 2018 for 402 115 patients with the 15 most prevalent cancer types was approximately $156.2 billion for privately insured adults younger than 65 years in the US. There were a total of 38.4 million documented procedure codes for 15 cancers in the MarketScan database, totaling $10.8 billion. Patients with breast cancer contributed the greatest total number of services (10.9 million [28.4%]), followed by those with colorectal cancer (3.9 million [10.2%]) and prostate cancer (3.6 million [9.4%]). Pathology and laboratory tests contributed the highest number of services performed (11.7 million [30.5%]), followed by medical services (6.3 million [16.4%]) and medical supplies and nonphysician services (6.1 million [15.9%]). The costliest cancers were those of the breast ($3.4 billion [31.5%]), followed by lung ($1.1 billion [10.2%]) and colorectum ($1.1 billion [10.2%]). Medical supplies and nonphysician services contributed the highest total spent ($4.0 billion [37.0%]), followed by radiology ($2.1 billion [19.4%]) and surgery ($1.8 billion [16.7%]).

CONCLUSIONS AND RELEVANCE

This analysis suggests that patients with breast, colorectal, and prostate cancers had the greatest number of services performed, particularly for pathology and laboratory tests, whereas patients with breast, lung, lymphoma, and colorectal cancer incurred the greatest costs, particularly for medical supplies and nonphysician services. The cost of cancer care in 2018 for the 15 most prevalent cancer types was estimated to be approximately $156.2 billion for privately insured adults younger than 65 years in the US.

Preliminary results of a phase II study of alrizomadlin (APG-115), a novel, small-molecule MDM2 inhibitor, in combination with pembrolizumab in patients (pts) with unresectable or metastatic melanoma or advanced solid tumors that have failed immuno-oncologic (I-O) drugs

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Background: Alrizomadlin (APG-115) restores TP53 function, activating p53-mediated apoptosis in tumor cells with wild-type TP53 and/or MDM2 amplification. Alrizomadlin also functions as a host immunomodulator and hence may restore antitumor activity in pts with cancers failing PD-1/PD-L1 blockade. Methods: This US multicenter trial assessed alrizomadlin combined with pembrolizumab in pts with unresectable/metastatic melanoma or advanced solid tumors that had failed I-O drugs; or pts with malignant peripheral nerve sheath tumor (MPNST), liposarcoma, or ATM mutant solid tumors that had failed any standard therapy. Eligible pts had ECOG performance status of 0-2 and no CNS metastases. The phase II study cohorts included pts with melanoma, NSCLC, solid tumor with ATM mutation, well-differentiated/dedifferentiated liposarcoma, urothelial carcinoma, and MPNST. Alrizomadlin was administered orally at 150 mg once every other day for 2 consecutive weeks with 1 week off and pembrolizumab at 200 mg via IV infusion for 30 minutes on Day 1 of a 21-day cycle. Results: As of December 25, 2020, 84 pts had been treated in 6 cohorts: melanoma (n = 26), NSCLC (n = 23), ATM mutation (n = 9), liposarcoma (n = 14), urothelial (n = 9), and MPNST (n = 3). In the PD-1/PD-L1 inhibitor-failed melanoma cohort, there was 1 confirmed partial response (PR) out of 5 pts with uveal melanoma, 2 PR (1 confirmed and 1 unconfirmed) of 5 pts with mucosal melanoma, and 1 confirmed PR of 11 pts with cutaneous melanoma. ORR in the melanoma cohort was 17.4% (4/23 evaluable pts), and the disease control rate was 60.9% (14/23). In the MPNST cohort, 1 of 3 pts had an unconfirmed ongoing PR. In I-O drug-failed NSCLC (n = 14 evaluable) and urothelial (n = 5 evaluable) cohorts, each reported 1 confirmed PR. Common treatment (alrizomadlin or pembrolizumab)-related adverse events (TRAEs) (≥ 10%) were nausea (63.1%), thrombocytopenia (36.9%), vomiting (33.3%), fatigue (31.0%), decreased appetite (27.4%), diarrhea (21.4%), neutropenia (15.4%), and anemia (11.9%). Grade ≥ 3 TRAEs (≥ 5%) included thrombocytopenia (20.2%), neutropenia (14.2%), and anemia (8.3%). Eleven pts discontinued treatment due to AEs: 5 were treatment related, including 2 grade 4 thrombocytopenia, and 1 each of grade 2 vomiting, grade 2 fatigue, and grade 2 posterior reversible encephalopathy syndrome (PRES). Three treatment-related SAEs were PRES, pyrexia, and asthenia. Conclusions: Alrizomadlin combined with pembrolizumab is well tolerated and may restore antitumor effects in pts with cancer resistant to or intolerant of I-O drugs, as suggested by preliminary antitumor activities in multiple tumor types. Internal study identifiers: APG-115-US-002; Keynote MK-3475-B66. Clinical trial information: NCT03611868.

Radiotherapy and Receptor Tyrosine Kinase Inhibition for Solid Cancers (ROCKIT): A Meta-Analysis of 13 Studies

Background

We hypothesized that the addition of receptor tyrosine kinase inhibitors (RTKis, e.g., lapatinib, erlotinib, cetuximab, bevacizumab, panitumumab) to radiotherapy-based treatment for solid tumors does not increase overall survival but may increase toxicity.

Methods

Population, Intervention, Control, Outcome, Study Design; Preferred Reporting Items for Systematic Reviews and Meta-Analyses; and Meta-analysis of Observational Studies in Epidemiology methods were used to identify prospective randomized studies including patients with solid tumor cancers treated with radiotherapy with or without RTKis. Extracted variables included use of radiotherapy vs chemoradiotherapy, RTKi type (antibody vs small molecule), outcomes, and toxicities. The primary endpoint was overall survival; the secondary endpoint was grade 3+ toxicity. Random-effects meta-analyses were performed for each outcome measure. All statistical tests were 2-sided.

Results

A total of 405 studies met the initial search criteria, of which 13 prospective randomized trials of radiotherapy with or without RTKi met the inclusion criteria, encompassing 5678 patients. The trials included cancers of the head and neck (6 trials, 3295 patients), esophagus (3 trials, 762 patients), lung (2 trials, 550 patients), and brain (2 trials, 1542 patients). Three studies evaluated a small molecule and radiotherapy in 949 patients, and 10 studies evaluated antibodies and radiotherapy in 4729 patients. The addition of RTKis to radiotherapy-based treatment did not improve overall survival (hazard ratio = 1.02, 95% confidence interval = 0.90 to 1.15, P = .76) but increased grade 3+ toxicity (relative risk = 1.18, 95% confidence interval = 1.06 to 1.33, P = .009).

Conclusions

The addition of RTKis to radiotherapy does not improve survival and worsens toxicity.

Neoadjuvant Pembrolizumab and High-Dose IFNα-2b in Resectable Regionally Advanced Melanoma

PURPOSE

Neoadjuvant immunotherapy may improve the clinical outcome of regionally advanced operable melanoma and allows for rapid clinical and pathologic assessment of response. We examined neoadjuvant pembrolizumab and high-dose IFNα-2b (HDI) therapy in patients with resectable advanced melanoma.

PATIENTS AND METHODS

Patients with resectable stage III/IV melanoma were treated with concurrent pembrolizumab 200 mg i.v. every 3 weeks and HDI 20 MU/m²/day i.v., 5 days per week for 4 weeks, then 10 MU/m²/day subcutaneously 3 days per week for 2 weeks. Definitive surgery followed, as did adjuvant combination immunotherapy, completing a year of treatment. Primary endpoint was safety of the combination. Secondary endpoints included overall response rate (ORR), pathologic complete response (pCR), recurrence-free survival (RFS), and overall survival (OS). Blood samples for correlative studies were collected throughout. Tumor tissue was assessed by IHC and flow cytometry at baseline and at surgery.

RESULTS

A total of 31 patients were enrolled, and 30 were evaluable. At data cutoff (October 2, 2019), median follow-up for OS was 37.87 months (range, 33.2-43.47). Median OS and RFS were not reached. Radiographic ORR was 73.3% [95% confidence interval (CI): 55.5-85.8], with a 43% (95% CI: 27.3-60.1) pCR rate. None of the patients with a pCR have had a recurrence. HDI and pembrolizumab were discontinued in 73% and 43% of patients, respectively. Correlative analyses suggested that intratumoral PD-1/PD-L1 interaction and HLA-DR expression are associated with pCR (P = 0.002 and P = 0.008, respectively).

CONCLUSIONS

Neoadjuvant concurrent HDI and pembrolizumab demonstrated promising clinical activity despite high rates of treatment discontinuation. pCR is a prognostic indicator.See related commentary by Menzies et al., p. 4133.

Avelumab in Combination with Eribulin Mesylate in Metastatic Urothelial Carcinoma: BTCRC GU-051, a Phase 1b Study

BACKGROUND

Patients with metastatic urothelial carcinoma (mUC) have poor prognosis, so further development of novel combinations for these patients is needed.

OBJECTIVE

To assess the safety and efficacy of eribulin mesylate (eribulin) with avelumab in mUC.

DESIGN, SETTING, AND PARTICIPANTS

This was an open-label, phase 1b study in which patients with mUC who were cisplatin-ineligible and treatment-naïve or platinum-resistant were treated with eribulin and avelumab. A 3 + 3 design was used. The study was prematurely terminated because the free study drug became unavailable, but we performed extended follow-up for patients enrolled in the study.

INTERVENTION

Patients received eribulin 1.1 mg/m² plus avelumab 10 mg/kg on days 1 and 15 in every 28-d cycle in cohort 0, or eribulin 1.4 mg/m² plus avelumab 10 mg/kg on days 1 and 15 in every 28-d cycle in cohort +1.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary objectives were to determine the maximum tolerated dose (MTD) of eribulin with avelumab and assess the objective response rate. A key secondary endpoint was to assess efficacy by evaluating the disease control rate. Exploratory endpoints included PD-1 expression on T cells in peripheral blood and in tumor cells, and tumor DNA sequencing.

RESULTS AND LIMITATIONS

A total of six patients were enrolled in the MTD group (n = 3 in cohort 0 and n = 3 in cohort +1). No dose-limiting toxicity (DLT) was observed in cohort 0, whereas two DLT events were observed in cohort +1. Two patients in cohort 0 had a partial response that was durable, with one patient having a durable response for 7.8 mo. Disease control was observed in 4/6 patients (66.7%). Owing to the early termination, MTD could not be determined.

CONCLUSIONS

While early termination of this trial precludes any definitive conclusions, the combination of eribulin and avelumab shows promise in mUC. We observed that treatment was better tolerated and efficacious at lower doses of eribulin. Further research is warranted for this combination in mUC.

PATIENT SUMMARY

We evaluated different doses of eribulin (a chemotherapy drug) in combination with a fixed dose of avelumab (an antibody used to treat several different cancers) in a small group of patients with metastatic cancer of the urinary tract. The lower dose of eribulin was easier to tolerate and the combination had an anti-cancer effect. This trial is registered at ClinicalTrials.gov as NCT03502681.

Phase II clinical study of concurrent durvalumab and radiation therapy (DUART) followed by adjuvant durvalumab in patients with localized urothelial cancer of bladder: Results for primary analyses and survival. BTCRC-GU15-023

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Background: Bladder cancer (BC) patients (pts) who are cisplatin ineligible/unfit for surgery, or locally advanced and unresectable have limited treatment options. DUART investigates if the combination of radiation therapy (RT) and checkpoint inhibitor, durvalumab (durva) is safe and effective in these pts. We recently reported that the combination was safe, tolerable and disease control rate (DCR) was 92% post durvaRT. Here we present interim efficacy data of our phase II study. Methods: Pts with pure or mixed urothelial bladder cancer (T2-4 N0-2 M0) were enrolled if their tumor was unresectable (35%), were unfit for surgery (50%) and/or cisplatin ineligible (89%). Primary endpoints: a) PFS at 1-yr b) DCR post adjuvant durva; Secondary endpoints: a) CR post durvaRT b) median PFS c) median OS. Pts were treated with durva (1500mg) Q4 wks x2 doses along with definitive RT (64.8Gy, 36 fractions over 7 wks) to the bladder and involved nodes followed by adjuvant durva Q4 wks x 1 yr. Response was evaluated with CT scan and cystoscopy+biopsy. Sample size was based on assumption that this regimen would increase 1 yr PFS by 25% compared to RT alone (50% to 75%); we assumed DCR of 75%. A total of 26 pts were needed to reach a statistical power of at least 80% at one-sided alpha of 5% and to allow for 10% drop out rate. Results: Twenty-six pts (19 males, 7 females) were enrolled, median age 74 yr (51-94). Sixty two percent of pts had >T2 disease, 31% had positive lymph nodes; 62% with unresectable tumor or were unfit for surgery due to comorbidities. At data cut off (9/30/2020) 20/26 pts were evaluable for DCR post adjuvant durva (3 pts with CR post durvaRT, did not get adjuvant therapy; 1 pt withdrew after 3 cycles for adjuvant durva and was on f/u with unconfirmed CR; 2 pts are still on adjuvant durva) and 25/26 for PFS and all 26 pts for OS. Post completion of adjuvant durva, DCR was seen in 70 % (14/20 with 10 CR; 3 PR; 1 SD; 6 PD). One-year probability of PFS was 73% (95% CI 56.4%, 94.4%), median PFS was 18.5 months. One-year OS probability was 83.8% (95% CI 70.4%, 99.7%) with two-year OS probability of 76.8 (95% CI 60.2%, 98%). Median OS has not been reached. We did not observe any correlation between clinical outcome and baseline tumor PD-L1 expression. Conclusions: DurvaRT followed by adjuvant durva demonstrated promising efficacy with 1-year PFS probability of 73%, 1- year OS probability of 83.8% and DCR of 70% in MIBC and locally advanced BC pts with comorbidities. Results will be updated prior to the final presentation. Efficacy was also seen in node (+) pts which led to the design of prospective randomized NCTN study. Induction chemo followed by chemo+durvaRT+ adjuvant durva vs. chemoRT combination is being evaluated in the ongoing EA8185 clinical trial (ECOG-ACRIN/NRG study) for node (+) BC pts. Clinical trial information: NCT02891161.

Group-led creative writing and behavioural health in cancer: a randomised clinical trial

BACKGROUND

Cancer diagnosis can adversely affect mental well-being and overall clinical outcome. We evaluated the efficacy of a group-led creative writing workshop (CWW) on mood in patients with cancer prospectively.

METHODS

We conducted a single-institution phase II study. Sixty adult patients with cancer (any type or stage) were randomised 2:1 to CWW (4×CWW sessions, bimonthly over 8 weeks) versus active control (AC) (independent writing at home with the help of a book, four sessions, bimonthly over 8 weeks). The total study duration was 6 months with a follow-up of up to 3 months.

PRIMARY OBJECTIVE

changes in overall mood, depression and anxiety symptoms before and after intervention in both arms. Emotional Thermometer Scale (ETS) was used to assess changes in patients' mood. Additionally, the Patient Health Questionnaire (PHQ)-9 and General Anxiety Disorder Scale (GAD)-7 were used to evaluate depression and anxiety symptoms.

RESULTS

Of 50 evaluable patients (CWW 34, AC 17), 26 patients in the CWW arm attended at least one class and 19 attended at least four classes. Patients in CWW had significant immediate improvement in the overall ETS (post vs preclass scores; p<0.0001, 95% CI -4.31 to -2.47). Four of the five subscale ETS scores were significantly lower for the CWW arm: distress (p=0.0346, 95% CI -2.6 to -0.1), anxiety (p=0.0366, 95% CI -4.1 to -0.2), depression (p=0.0441, 95% CI -3.9 to -0.1) and anger (p=0.0494, 95% CI -3.3 to 0). No significant differences were seen in the AC arm. No significant differences were observed in the PHQ-9 or the GAD-7 scores.

CONCLUSION

CWW had a positive effect on mood based on ETS scores, suggesting a potential therapeutic benefit among patients with cancer.

The exercise in all chemotherapy trial

BACKGROUND

Multiple international organizations have called for exercise to become standard practice in the setting of oncology care. The feasibility of integrating exercise within systemic chemotherapy has not been investigated.

METHODS

Patients slated to receive infusion therapy between April 2017 and October 2018 were screened for possible inclusion. The study goal was to establish the acceptability and feasibility of embedding an exercise professional into the chemotherapy infusion suite as a method of making exercise a standard part of cancer care. The exercise prescriptions provided to patients were individualized according to results of brief baseline functional testing.

RESULTS

In all, 544 patients were screened, and their respective treating oncologists deemed 83% of them to be medically eligible to participate. After further eligibility screening, 226 patients were approached. Nearly 71% of these patients (n = 160) accepted the invitation to participate in the Exercise in All Chemotherapy trial. Feasibility was established because 71%, 55%, 69%, and 63% of the aerobic, resistance, balance, and flexibility exercises prescribed to patients were completed. Qualitative data also supported the acceptability and feasibility of the intervention from the perspective of patients and clinicians. The per-patient cost of the intervention was $190.68 to $382.40.

CONCLUSIONS

Embedding an exercise professional into the chemotherapy infusion suite is an acceptable and feasible approach to making exercise standard practice. Moreover, the cost of the intervention is lower than the cost of other common community programs. Future studies should test whether colocating an exercise professional with infusion therapy could reach more patients in comparison with not colocating.

LAY SUMMARY

Few studies have tested the implementation of exercise for patients with cancer by embedding an exercise professional directly into the chemotherapy infusion suite. The Exercise in All Chemotherapy trial shows that this approach is both acceptable and feasible from the perspective of clinicians and patients.

Alterations of DNA damage response genes correlate with response and overall survival in anti-PD-1/PD-L1-treated advanced urothelial cancer

DNA damage response (DDR) gene alterations in cancer are associated with a higher tumor mutational burden (TMB) and may impact clinical outcomes of urothelial cancer (UC). Here, we explore the prognostic role of DDR alterations in advanced UC treated with anti-PD-1/PD-L1 agents. The study included 53 patients who had FoundationOne genomic sequencing and received anti-PD-1/PD-L1 therapy. Fisher exact test and trend test were used to assess differences in objective response rate (ORR). Overall survival (OS) was measured from the time of initial UC diagnosis and Cox proportional hazard regression analysis was performed to calculate hazard ratio (HR) and 95% confidence interval (CI). The cohort had a median age of 66 with 64% receiving platinum-based chemotherapy. DDR alterations (including ATM) were associated with a non-significantly higher ORR to PD-1/PD-L1 blockade (41% vs. 21%, p = 0.136). Patients with DDR alterations (excluding ATM) had non-significantly longer OS, likely due to a small sample size (HR = 0.53, 95% CI 0.20-1.38, p = 0.19). ATM alterations were associated with a non-significantly higher ORR (40% vs. 29%, p = 0.6), but also with significantly shorter OS (HR = 5.7, 95% CI 1.65-19.74, p = 0.006). Patients with ≥ 3 DDR alterations (including ATM) had substantially higher TMB (p = 0.01) and higher ORR (80%) with PD-1/PD-L1 blockade versus 24% ORR in patients with <3 DDR alterations. In summary, DDR alterations were associated with non-significantly higher ORR and longer OS for patients with advanced UC receiving anti-PD-1/PD-L1 agents. ATM alterations were associated with shorter OS.

Phase I Clinical Trial of Combination Propranolol and Pembrolizumab in Locally Advanced and Metastatic Melanoma: Safety, Tolerability, and Preliminary Evidence of Antitumor Activity

PURPOSE

Increased β-adrenergic receptor (β-AR) signaling has been shown to promote the creation of an immunosuppressive tumor microenvironment (TME). Preclinical studies have shown that abrogation of this signaling pathway, particularly β2-AR, provides a more favorable TME that enhances the activity of anti-PD-1 checkpoint inhibitors. We hypothesize that blocking stress-related immunosuppressive pathways would improve tumor response to immune checkpoint inhibitors in patients. Here, we report the results of dose escalation of a nonselective β-blocker (propranolol) with pembrolizumab in patients with metastatic melanoma.

PATIENTS AND METHODS

A 3 + 3 dose escalation study for propranolol twice a day with pembrolizumab (200 mg every 3 weeks) was completed. The primary objective was to determine the recommended phase II dose (RP2D). Additional objectives included safety, antitumor activity, and biomarker analyses. Responders were defined as patients with complete or partial response per immune-modified RECIST at 6 months.

RESULTS

Nine patients with metastatic melanoma received increasing doses of propranolol in cohorts of 10, 20, and 30 mg twice a day. No dose-limiting toxicities were observed. Most common treatment-related adverse events (TRAEs) were rash, fatigue, and vitiligo, observed in 44% patients. One patient developed two grade ≥3 TRAEs. Objective response rate was 78%. While no significant changes in treatment-associated biomarkers were observed, an increase in IFNγ and a decrease in IL6 was noted in responders.

CONCLUSIONS

Combination of propranolol with pembrolizumab in treatment-naïve metastatic melanoma is safe and shows very promising activity. Propranolol 30 mg twice a day was selected as RP2D in addition to pembrolizumab based on safety, tolerability, and preliminary antitumor activity.

Toxicity in combination immune checkpoint inhibitor and radiation therapy: A systematic review and meta-analysis

BACKGROUND AND PURPOSE

Immune checkpoint inhibitor with radiation therapy (ICI + RT) is under investigation for improved patient outcome, so we performed a systematic review/meta-analysis of toxicities for ICI + RT compared to immune checkpoint inhibitor (ICI) therapy alone.

MATERIALS AND METHODS

A PRISMA-compliant systematic review of studies in MEDLINE (PubMed) and in the National Comprehensive Cancer Network guidelines was conducted, with primary outcome grade 3 + toxicity. Criteria for ICI alone were: phase III/IV trials that compared immunotherapy to placebo, chemotherapy, or alternative immunotherapy; and for ICI + RT: prospective/retrospective studies with an arm treated with ICI + RT. Meta-analysis was performed by random effects models using the DerSimonian and Laird method. The I² statistic and Cochran's Q test were used to assess heterogeneity, while funnel plots and Egger's test assessed publication bias.

RESULTS

This meta-analysis included 51 studies (n = 15,398), with 35 ICI alone (n = 13,956) and 16 ICI + RT studies (n = 1,442). Our models showed comparable grade 3-4 toxicities in ICI + RT (16.3%; 95% CI, 11.1-22.3%) and ICI alone (22.3%; 95% CI, 18.1-26.9%). Stratification by timing of radiation and irradiated site showed no significant differences, but anti-CTLA-4 therapy and melanoma showed increased toxicity. The grade 5 toxicities were 1.1% and 1.9% for ICI alone and ICI + RT respectively. There was significant heterogeneity, but not publication bias.

CONCLUSIONS

The random effects model showed comparable grade 3-4 toxicity in using ICI + RT compared to ICI alone in CNS melanoma metastases, NSCLC, and prostate cancer. ICI + RT is safe for future clinical trials in these cancers.

Growth factor and its role in the treatment of patients with soft tissue extremity sarcoma receiving chemotherapy managed at an academic center: A retrospective study

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Background: Surgery still remains the mainstay of treatment with curative intent for high grade extremity soft tissue non rhabdomyosarcoma sarcomas (HG ESTS). Adjuvant/neoadjuvant Chemotherapy (CT) is still debatable, but most experts agree about its role in HG-ESTS in combination with radiation (R). Interdigitated CT+R is an attractive method of delivering these modalities of treatment in short time prior to surgery, however safety of using growth factor (GF) while administering CT+R in HG ESTS is largely unknown. We conducted a retrospective study of the toxicities associated with GF administration in this setting at a single institution. Methods: Electronic medical records at one institution were reviewed to identify patients having a diagnosis of extremity STS between October 2017- January 2020. Demographics, details of tumor characteristics, and treatment details were noted. Details of Interdigitated (ID)CRT were noted; the intended CT regimen was doxorubicin/ifosphamide/mesna (MAI) at 100% of the intended dosing. Data regarding the toxicities associated with GF administration were also evaluated in these patients; specifically, the development of febrile neutropenia, thrombocytopenia and pulmonary toxicity were evaluated. Patients who presented with metastatic disease were excluded from this analysis. Results: 22 patients were identified. Median age was 63 years. Of these, 9 patients (40%) were smokers. At diagnosis, 6 patients (27%) had metastatic disease. The most common site of primary disease was the thigh (50%). The most common histology was undifferentiated pleomorphic sarcoma (59%). CT monotherapy was administered in 3 patients. RT was administered in 14 patients, out of whom interdigitated CRT was administered in 10 patients. 60% of patients who initiated were able to receive 3 cycles of ID-CRT prior to Surgery. GF was administered in 14 patients who received regimens including CT. Of patients receiving ID-CRT who received GF, 60% completed ID-CRT without delays. No delays occurred due to thrombocytopenia. Febrile neutropenia occured in 22% of patients who received GF. Only 1 patient who received GF suffered prolonged thrombocytopenia. No patients who received GF were noted to have pulmonary toxicity. Conclusions: For adults with HG ESTS, GF administration with ID-CRT does not appear to cause any additional delay in treatment due to prolonged thrombocytopenia or lung toxicity. Inclusion of GF administration in further prospective trials of ID-CRT appears feasible.

Serum biomarkers of inflammation (ferritin, IL-8, TNFR1) and outcomes in BOLERO-2, a phase III trial of HR+/HER2- metastatic breast cancer treated with everolimus (mTOR inhibitor)

1067

Background: Everolimus (EVE) plus exemestane (EXE) doubled PFS while maintaining quality of life versus EXE alone in postmenopausal hormone receptor-positive (HR+), HER2-negative metastatic breast cancer (MBC) (BOLERO-2 phase 3; NCT00863655). Here we investigated several serum biomarkers of inflammation: ferritin, interleukin-8 (IL-8), and tumor necrosis factor receptor 1 (TNFR1). Both higher IL-8 (ASCO 2018, #3025) and TNF (Nature 569:428-32, 2019) have been reported to be associated with worsened outcome to immune checkpoint inhibitors (ICI), and IL-8- and TNF-targeted therapies combined with ICIs are in phase I trials. We evaluated the prognostic/predictive ability of serum ferritin, IL-8, and TNFR1 to everolimus in BOLERO-2. Methods: Serum biomarkers were determined on pretreatment serum samples using the ELLA immunoassay platform (ProteinSimple, San Jose, CA). Cox-proportional hazards model was used to assess the efficacy of EVE, and the prognostic and predictive effect on PFS and OS. Results: Pretreatment serum biomarker levels were determined in 510 patients (70 %) of 725 BOLERO-2 patients randomized 2:1 to EVE+EXE or EXE). Serum levels (25%, 50%, 75%) were: ferritin (68.9, 125.5, 253.1 ng/ml); IL-8 (14.5, 19.4, 27.7 pg/ml); and TNFR1 (1205, 1470, 1868 pg/ml). Ferritin correlated significantly with TNFR1 (r=0.45, p<0.0001), while IL-8 correlated weakly with TNFR1 (r=0.10, p=0.023). Higher levels of all 3 biomarkers were prognostic for significantly shorter PFS and OS (table). But no biomarkers were predictive: everolimus was efficacious regardless of the 3 biomarker levels (p>0.05). Conclusions: High levels of serum ferritin, IL-8, and TNFR1 were significantly associated with shorter PFS and OS in HR+/HER2- MBC patients. Everolimus had superior outcomes compared to placebo, regardless of serum biomarker level. These 3 significant prognostic biomarkers are all associated with increased inflammatory processes through different pathways. Anti-inflammatory therapy targeted against these biomarkers should be evaluated based on serum level as potential combination therapy with everolimus or CDK 4/6 inhibitors in HR+ MBC. [Table: see text]

Plasma IL-8 and PD-L1 and overall survival in metastatic castration-resistant prostate cancer patients (mCRPC)

e17565

Background: We previously reported the significant prognostic and predictive utility of pretreatment serum PD-L1 in the CCTG MA.31 breast cancer serum bank (SABCS 2018, abstr PD3-10). IL-8 (CXCL8) is a pro-inflammatory cytokine that binds to CXCR1 and CXCR2 and promotes tumor immune escape and progression. High serum IL-8 levels are associated with poor prognosis in many cancers, and have recently been reported to predict for reduced overall survival (OS) to nivolumab in lung cancer and melanoma (ASCO 2018, abstr #3025). Here we correlated plasma IL-8 and PD-L1 levels with OS in mCRPC patients. Methods: 201 metastatic CRPC patients had EDTA plasma available for this retrospective analysis. Patient eligibility included chemotherapy-naive mCRPC patients. The ELLA immunoassay platform (ProteinSimple, San Jose, CA) was utilized to quantitate plasma IL-8 and PD-L1. Cox regression assessed hazard ratio (HR) for OS using both categorical (median) and continuous (log-transformed) biomarkers. Results: In univariate analysis, higher plasma IL-8 levels were significantly associated with reduced OS when analyzed as a continuous variable (HR = 1.53; p = 0.003) and were of borderline significance at the median cutpoint (HR = 1.32; p = 0.069; 20.9 vs 31.5 mos median OS). Plasma PD-L1 levels were not significantly associated with OS when analyzed as a continuous variable (p = 0.17), but increased levels were significant when analyzed at the median cutpoint (HR = 1.36; p = 0.044; 21.9 vs 29.0 mos median OS). When plasma IL-8 and PD-L1 levels were combined (median cutpoints), plasma IL-8 high / PD-L1 high patients (n = 58) had a significantly shorter OS vs the plasma IL-8 low / PD-L1 low patients (n = 58) (HR = 1.69; p = 0.009; 19.3 vs 32.9 mos median OS, respectively). In multivariate analysis, when adjusted for biopsy Gleason score, age, PSA, and ECOG PS (all at time of blood draw), only high plasma IL-8 (on a continuous basis) was significantly associated with reduced OS (HR = 1.43; p = 0.019). Conclusions: In mCRPC patients, high plasma IL-8 and PD-L1 levels were associated with reduced OS (separately and combined). Circulating IL-8 and PD-L1 evaluation may inform prognosis in mCRPC and could be considered as biomarkers in future studies determining response to immune checkpoint inhibitor and anti-IL8 therapy.

Investigating the impact of medical comorbidities in patients taking beta blockers and treated with immunotherapy for metastatic melanoma

e15162

Background: Combined administration of β-adrenergic antagonist with IL-2, anti-PD-1, and/or anti-CTLA-4 immunotherapy was associated with a better overall survival in metastatic melanoma patients. This result was also reinforced by the significant reduction in tumor growth in a murine melanoma model when a β2-selective antagonist was combined with anti-PD1/IL-2 immunotherapy. Here we sought to elucidate the impact of the various comorbidities behind the indications of β-blockers, and how they might have influenced the patients’ immunotherapy treatment response. Methods: A single-institution retrospective chart review was performed to examine the medical comorbidities with indications for β-blockers in the melanoma patients who received IL-2, αPD-1 and/or αCTLA-4 immunotherapy between January 2000 and March 2015. Two groups were identified: one that took a selective β-1 blocker (N = 41), and another that took a nonselective pan β-blocker (N = 17). The primary analysis compared the distribution of different comorbidity types between two groups, using the Fisher’s exact test. A secondary analysis examined the association of overall survival and the β-blocker groups by further controlling for comorbid conditions, using the multivariate Cox Proportional-Hazard regression model. Results: Seven different comorbidities with indications for β-blocker usage were identified. Of those comorbidities, only the presence of ischemic heart disease was marginally different between the two groups (β-1 group 19.5% vs. pan-β group 47.1%, p-value = 0.0697). There was no difference for overall survival between each of the comorbidity conditions. When performing the multivariate Cox Proportional-Hazard regression model, β-blocker usage still remained statistically significant for the overall survival (HR 0.27, CI 0.0966-0.768, p = 0.0139), even after controlling for the comorbid conditions. Conclusions: Immunotherapy with pan β-adrenergic blockade was associated with a significantly improved overall survival rate for metastatic melanoma. Furthermore, having a comorbid condition that indicated for the prescription of β-blockers was not a factor in establishing this survival rate.

Prognostic Value of DNA Damage Response Genomic Alterations in Relapsed/Advanced Urothelial Cancer

BACKGROUND

DNA damage response (DDR) genomic alterations may play an important role in clinical outcomes of patients with urothelial cancer (UC). However, data on the prognostic role of DDR gene alterations in patients with advanced UC remain unclear.

MATERIALS AND METHODS

We retrospectively collected data of three independent patient cohorts with relapsed or advanced UC including 81 and 91 patients from four institutions who underwent FoundationOne genomic sequencing as well as 129 patients selected from The Cancer Genome Atlas bladder cohort. Fisher's exact test was used to determine differences of mutation frequency among the three cohorts. Logistic regression analysis was performed to calculate odds ratio (OR) and 95% confidence interval (CI). Overall survival (OS) was measured from time of initial diagnosis and Cox proportional hazard regression analysis was performed to calculate the hazard ratio (HR) and 95% CI.

RESULTS

DDR genomic alterations were present in 76.5% (62/81), 40.7% (37/91), and 51.2% (66/129) of the three cohorts. ATM alterations consistently correlated with significantly shorter OS, whereas other DDR alterations (excluding ATM) were associated with better prognosis. In 152 patients treated with platinum pooled from the three cohorts, the prognostic value of alterations in ATM as compared with other predefined DDR genes was substantially different (ATM: adjusted HR [HR], 2.03; 95% CI, 1.03-4; p = .04; other DDR: adjusted HR, 0.49; 95% CI, 0.31-0.8; p = .003).

CONCLUSIONS

Genomic alterations in ATM and other DDR genes may have opposite prognostic value in relapsed and/or advanced UC. ATM may have a complex role in UC progression.

IMPLICATIONS FOR PRACTICE

Somatic mutations of DNA damage response (DDR) genes are frequently found in urothelial cancer and appear to play an important role in tumorigenesis, progression, treatment response, and outcomes. In a set of DDR genes, ATM alterations were associated with worse survival, while other alterations were associated with better survival in advanced urothelial cancer. The results of this study suggest a complex role of ATM in tumor progression and call for further studies to determine the underlying mechanisms and biomarker clinical utility.

A phase Ib study targeting PIM1 and CDK4/6 kinases in metastatic renal cell carcinoma (PICKRCC)

TPS771

Background: Over the last few years there has been a rapid increase in the clinically relevant agents available to treat metastatic renal cell carcinoma (mRCC). We note, however, that the vast majority of new agents available for mRCC do not exploit new clinical targets or pathways. We believe that the identification of new, clinically relevant targets in RCC will propel the field even further forward, expand treatment options, and lead to improved survival for mRCC patients. SGI-1776, a selective PIM1 kinase inhibitor, has previously been shown to induce reduction in tumor size as monotherapy and in combination with sunitinib in mouse pre-clinical studies of RCC. In our tissue microarray studies a subset of ~26% of RCC showed high staining for PIM1 kinase while only 1% of normal adjacent tissue showed similar high staining. Wildtype PIM1 is constitutively active, thus these data suggest that PIM1 activity is increased in a subset of RCC. Abemaciclib is a potent CDK4/6 inhibitor with an IC50 of 2 and 10 nM, respectively. It is also a potent PIM1 inhibitor with an IC50 of 50 nM. We have shown that abemaciclib decreases cell viability and increases apoptosis in RCC cell lines, and does so at greatest effect in combination with sunitinib. We have also shown that abemaciclib induces regression of RCC tumors in a mouse model of RCC, with the most rapid responses observed when abemaciclib is combined with sunitinib. Based on these data we have opened a phase Ib dose escalation study to determine the safety and tolerability of abemaciclib in combination with sunitinib in patients with mRCC. The study includes an expansion cohort at the recommended phase II dose to evaluate for a signal for efficacy. Pattern and intensity of PIM1 staining in tumor tissue will be evaluated as a potential biomarker of response. We are also collecting blood and urine to evaluate additional potential biomarkers of response. Methods: Clinical trial information: NCT03905889 .[Table: see text]

Concurrent durvalumab and radiation therapy followed by adjuvant durvalumab in patients with locally advanced urothelial cancer of bladder (DUART): Btcrc-GU15-023

513

Background: Bladder cancer (BC) patients (pts) who are cisplatin ineligible/unfit for surgery, unresectable have limited treatment options. In this study, we investigate if the combination of radiation therapy (RT) and checkpoint inhibitor, durvalumab (durva) is safe and effective in these pts. Our results from phase (ph) Ib suggested that the combination was safe. Here we present the response rate post durvaRT and updated treatment related adverse events (TRAEs) amongst our evaluable pts in ph II. Methods: This is a single arm ph Ib-II study for T2-4 N0-2 M0 pts. The ph II primary endpoints a) PFS rate at 1 yr b) disease control rate (DCR); secondary endpoints were a) CR post durvaRT b) PFS c) OS. Pts were treated with durva (1500mg) Q4 wks x2 doses along with definitive RT (64.8Gy, 36 fractions over 7 wks) to the bladder and involved nodes followed by adjuvant durva Q4 wks x 1 yr. Response was evaluated with CT scan and cystoscopy+biopsy post durvaRT. We anticipated that durvaRT followed by durva would increase PFS at 1 yr from 50% to 75% when compared to RT; we assumed DCR of about 75%. A total of 26 pts were needed to reach a statistical power of at least 80% at one-sided alpha of 5% and to allow for 10% drop out rate. Results: Total N = 26 patients (male 19; female 7, median age 74yr). At the time of data cut off, 21/26 pts were evaluable for response post durvaRT. Post completion of durvaRT time point, clinical CR was seen in 15/21 pts (71.4%); PR 1/21 pts (4.7%); SD 4/21 (19%); PD 1/21 (4.7%). DCR was seen in 20/21 pts (95%) post durvaRT. Median follow up from D1 to last follow up was 6.1 mos. Grade ≥ 3 TRAE amongst 26 pts: anemia (1/26), lipase/amylase (1/26), immune nephritis (1/26), dyspnea (gr 4, copd/immune), fatigue (1/26), lymphopenia (6/26). Other TRAEs: Fatigue was the most common TRAE (16/26); UTI (5/26); cystitis (3/26). No fatal TRAEs were observed. Conclusions: DurvaRT demonstrated promising efficacy with clinical CR of 71.4% and DCR of 95% in unresectable, cisplatin ineligible locally advanced BC. It was generally well tolerated. Ph II study has completed accrual and longer-term results will further our understanding of this regimen’s efficacy in locally advanced BC. Clinical trial information: NCT02891161.

Abstract P4-10-25: Pretreatment serum metabolome predicts PFS in first-line trastuzumab-treated metastatic breast cancer

Background: Cancer cells have altered metabolism, which contributes to their ability to proliferate, survive in unusual microenvironments, and invade other tissues. Measuring the complete set of metabolites in an individual (i.e. the metabolome) provides a functional readout for cellular pathways. Further, changes in the metabolome can be correlated with disease status, prognosis and progression. Using a metabolomics platform and machine learning algorithms, biomarker signatures can be identified to predict response to therapy. Metabolite analysis of pretreatment plasma has shown promise for predicting response in a small retrospective study of the CDK 4/6 inhibitors palbociclib and ribociclib in hormone receptor-positive metastatic breast cancer (Zhang B et al, ASCO 2019 Abstr 3043). HER2-positive metastatic breast cancer patients have significant heterogeneity in response and progression-free survival (PFS) to HER2-targeted therapy. Here we retrospectively evaluated the pretreatment serum metabolome for association with PFS in a cohort of trastuzumab-treated metastatic breast cancer patients from a single institution. Methods: Pretreatment serum from 26 HER2-positive trastuzumab-naive metastatic breast cancer patients who were treated with first-line trastuzumab and chemotherapy were included in this exploratory analysis. Metabolites were extracted from previously frozen serum (1 mL) using ice-cold methanol and chloroform. The resulting metabolites were isolated and quantified using an unbiased, non-destructive, nuclear magnetic resonance (NMR)-based profiling platform (Olaris, Inc., Cambridge, MA). The serum was analyzed via 1D 1H NMR and 2D 13C-1H heteronuclear single quantum coherence spectroscopy (HSQC) using customized non-uniform sampling (NUS) techniques and processed with proprietary Olaris software. Supervised and unsupervised machine learning algorithms were used to identify patients with shorter and longer PFS to trastuzumab-based therapy. Results: The median PFS for this cohort was 301 days. Patients were subdivided into early progressors (PFS &lt; 301 days) and late progressors (PFS ≥ 301 days). 23 metabolite resonance levels were statistically different between the two groups (KW test p&lt;0.05, 11 metabolites expected by chance). Using advanced machine learning we constructed a model based on 5 metabolite resonances that showed significant discriminatory ability with an AUC of 0.964 using receiver-operating curve (ROC) analysis. 21 of the 26 patients received trastuzumab and chemotherapy as a first-line therapy, while the remaining 5 patients received first-line trastuzumab with subsequent chemotherapy, after 1 or more lines of previous chemotherapy for metastatic disease. We repeated our analysis using only the first-line therapy subgroup and identified a partially overlapping set of metabolite resonances that could nearly perfectly discriminate early and late progressors with an AUC of 0.973. Further efforts are underway to confirm the identity of these metabolites. Conclusions: Metabolic profiling of pretreatment serum using NMR was successful in identifying a biomarker signature that predicted PFS to trastuzumab in HER2-positive metastatic breast cancer. Expanded metabolome analysis is warranted in larger cohorts and clinical trials to confirm that this serum biomarker signature predicts PFS to trastuzumab therapy, particularly in the first-line setting. Further, by identifying the metabolites and metabolic pathways that differ between early and late progressors, it may be possible to identify novel targets and/or suggest combination treatments in the HER2-positive metastatic breast cancer setting.

Citation Format: Elizabeth O'Day, Kim Leitzel, Suhail M Ali, Bo Zhang, Chen Dong, Haiwei Gu, Xiajian Shi, Joseph J Drabick, Leah Cream, Monali Vasekar, Hyma V Polimera, Vinod Nagabhairu, Prashanth Moku, Ashok Maddukuri, Harry Menon, Neha Pancholy, Walter P Carney, Wolfgang Koestler, Allan Lipton. Pretreatment serum metabolome predicts PFS in first-line trastuzumab-treated metastatic breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P4-10-25.

Identifying the Optimal Fractionation Schedules for Improved Response Rates and Survival in Patients with Metastatic Melanoma Treated with Ipilimumab and Radiotherapy

Objective:

There is a growing body of evidence that combining ipilimumab with higher doses of radiotherapy may improve the response rates and survival in patients with metastatic melanoma compared to lower doses of radiotherapy. However, the dose cutoff at which improved outcomes are more likely to occur has not been properly identified.

Methods:

We conducted a retrospective analysis of 100 patients treated with ipilimumab and radiotherapy for metastatic melanoma at a single institution from May 2011 to January 2017. Demographic, clinical, and treatment factors, including the biological equivalent dose (BED) with an α/β of 7, were recorded. Endpoints of interest included infield and global complete response (CR) after the completion of radiation and ipilimumab based on the RECIST criteria (v1.1) and 12-month overall survival (OS).

Results:

The BED cutoffs at which improved outcomes are more likely to occur are 46.5 Gy for infield CR, 50.9 Gy for global CR, and 46.5 Gy for 12 month OS. The least aggressive fractionation schedules used in this patient population that have a BED above the threshold for all 3 outcomes include 40 Gy in 20 fractions, 30 Gy in 6 fractions, and 24 Gy in 3 fractions.

Conclusion:

This hypothesis-generating study suggests that patients who cannot receive ablative intent radiotherapy may be more likely to benefit from concurrent radiotherapy with ipilimumab if their fractionation schedule has a BED above 46.5 - 50.9 Gy. Prospective trials evaluating this question should be considered.

Collagen fragments quantified in serum as measures of desmoplasia associate with survival outcome in patients with advanced pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) patients have poor prognosis and poor response to treatment. This is largely due to PDAC being associated with a dense and active stroma and tumor fibrosis (desmoplasia). Desmoplasia is characterized by excessive degradation and formation of the extracellular matrix (ECM) generating collagen fragments that are released into circulation. We evaluated the association of specific collagen fragments measured in pre-treatment serum with outcome in patients with PDAC. Matrix metalloprotease (MMP)-degraded type I collagen (C1M), type III collagen (C3M), type IV collagen (C4M) and a pro-peptide of type III collagen (PRO-C3) were measured by ELISA in pre-treatment serum from a randomized phase 3 clinical trial of patients with stage III/IV PDAC treated with 5-fluorouracil based therapy (n = 176). The collagen fragments were evaluated for their correlation (r, Spearman) with serum CA19-9 and for their association with overall survival (OS) based on Cox-regression analyses. In this phase 3 PDAC trial, pre-treatment serum collagen fragment levels were above the reference range for 67%-98% of patients, with median values in PDAC approximately two-fold higher than reference levels. Collagen fragment levels did not correlate with CA19-9 (r = 0.049–0.141, p = ns). On a continuous basis, higher levels of all collagen fragments were associated with significantly shorter OS. When evaluating degradation (C3M) and formation (PRO-C3) of type III collagen further, higher PRO-C3 was associated with poor OS (>25^th percentile cut-point, HR = 2.01, 95%CI = 1.33–3.05) and higher C3M/PRO-C3 ratio was associated with improved OS (>25^th percentile cut-point, HR = 0.53, 95%CI = 0.34–0.80). When adjusting for CA19–9 and clinical covariates, PRO-C3 remained significant (HR = 1.65, 95%CI = 1.09–2.48). In conclusion, collagen remodeling quantified in pre-treatment serum as a surrogate measure of desmoplasia was significantly associated with OS in a phase 3 clinical PDAC trial, supporting the link between desmoplasia, tumorigenesis, and response to treatment. If validated, these biomarkers may have prognostic and/or predictive potential in future PDAC trials.

Postoperative chemotherapy and radiation improve survival following cardiac sarcoma resection

OBJECTIVE

Cardiac sarcoma represents a rare and aggressive form of cancer with a paucity of data to produce outcome-driven evidence-based guidelines. Current surgical management consists of resection with postoperative therapy (chemotherapy, radiation, or both) offered on a selective, individualized basis. This study was designed to determine whether postoperative therapy was associated with improved overall survival after resection.

METHODS

The National Cancer Database was used to identify patients with cardiac sarcoma between 2004 and 2015. Patient characteristics were stratified by treatment (surgical, nonsurgical, and none), and treatment was analyzed by stage. Overall survival, assessed with Kaplan-Meier methodology, was compared between patients who received postoperative therapy and those who did not following resection. Multivariable survival modeling using a Weibull model identified risk factors associated with survival while controlling for confounders.

RESULTS

The study included 617 patients diagnosed with cardiac sarcoma. Only 24% (149/617) of patients were diagnosed with early-stage disease. Angiosarcoma represented 48% (298/617) of cases and was the most commonly identified histologic subtype. 60% (372/617) underwent surgical resection and 58% (216/372) of those patients were treated with postoperative therapy. Following surgery, median survival was more than doubled for patients treated with postoperative therapy (19 months vs 8 months, P = .026). However, 5-year overall survival was similar between the groups. Multivariable analysis confirmed an improvement in survival with postoperative therapy (hazard ratio, 0.68; 95% confidence interval, 0.51-0.91, P = .009).

CONCLUSIONS

Postoperative therapy is associated with better median survival following resection of cardiac sarcoma. However, at 5 years, the difference in overall survival is not statistically significant.

Attendance at National Cancer Institute and Children's Oncology Group Facilities for Children, Adolescents, and Young Adults with Cancer in Pennsylvania: A Population-Based Study

Purpose: Adolescents and young adults (AYAs) with cancer are a vulnerable population with decreased attendance at National Cancer Institute (NCI) comprehensive cancer centers and Children's Oncology Group (COG) facilities. Decreased attendance at NCI/COG facilities has been associated with poor cancer outcomes. The objective of this study was to evaluate cancer care patterns of AYAs compared with children, within Pennsylvania, and factors associated with attending an NCI/COG facility. Methods: Data from the Pennsylvania Cancer Registry between 2010 and 2015 for patients aged 0-39 years at cancer diagnosis were used. Primary analyses focused on age at diagnosis, insurance status, race, ethnicity, gender, cancer type, stage, diagnosis year, and distance to the NCI/COG facility. The primary outcome was receipt of care at an NCI/COG facility. Odds ratios (ORs) were calculated using multivariable logistic regression models. Sensitivity analyses were conducted to test and estimate robustness. Results: A sample of 15,002 patients, ages 0-39, was obtained, including 8857 patients (59%) who attended an NCI/COG facility. Patients were significantly less likely to attend an NCI/COG facility if they were aged 31-39 years (OR 0.054, 95% confidence interval [CI] 0.04-0.07), non-White (OR 0.890, 95% CI 0.80-0.99), Hispanic (OR 0.701, 95% CI 0.59-0.83), female (OR 0.915, 95% CI 0.84-1.00), had Medicaid insurance (OR 0.836, 95% CI 0.75-0.93), and lived further from an NCI/COG facility. Sensitivity analyses largely corroborated the performed estimates. Conclusions: AYAs with cancer in Pennsylvania have disproportionate attendance at specialized NCI/COG facilities across a variety of demographic domains. Enhancing the attendance of AYAs with cancer at these specialized centers is crucial to improve cancer outcomes.

A phase I study of neoadjuvant combination immunotherapy in locally/regionally advanced melanoma

9586

Background: A trial of neoadjuvant pembrolizumab (P) in combination with high dose interferon-α (HDI) in high-risk patients (pts) with locoregionally advanced melanoma (mel) has completed enrollment. Methods: Primary endpoint: safety of combination P-HDI. Pts were treated with P x 2 doses followed by definitive surgery, then x1 year. HDI was given concurrently, and both agents were per standard regimen. Tumor and blood samples were obtained at baseline and at surgery (wk 6-8), blood at 6 wks, 3,6,12 months (mos). Results: 30 pts were treated (22 male, 8 female, age 26-83). 16 had cutaneous primary, 3 mucosal, 11 unknown. At enrollment, 16 had recurrent disease, 6 received prior adjuvant therapy with ipilimumab (4) or HDI (2). 16 had AJCC 7 stage IIIB, 9 IIIC, 5 IV. 332 P cycles have been delivered (median 13), 496 doses of HDI induction (median 17), 1329 doses of HDI maintenance (median 44). HDI was dose reduced in 20 pts, discontinued in 27, P discontinued in 8. Radiologic preoperative RR was 77% (95% CI, 59-88) (6 CR, 17 PR). 20% (6) had SD and 1 had PD. All pts underwent definitive surgery. The pathologic complete response (pCR) of 26 pts was 32% (95% CI, 18-51). 6 pts recurred and 3 died. No pt with pCR has recurred. Median f/u time is 17.4 mos, median PFS/OS not reached. Most common grade (Gr) 3 toxicities: hypophosphatemia (10; 33%), fatigue (10; 33%), ↑CPK (6; 20%), ↑lipase (4; 13%). 3 Gr 4 events (↑CPK, hyperglycemia, lymphocyte count decreased). 1 suspected grade 5 event occurred 6 months after completion of therapy. PD-L1 expression at baseline did not correlate with clinical outcomes. In 8 pts with pre and post treatment tumor samples, IHC expression of PD-1, PD-L1, CD11b, CD8, Foxp3 and CD25 increased post-treatment (p < 0.05). Conclusions: Neoadjuvant P-HDI has promising clinical activity, although treatment is limited by HDI toxicity. Treatment increases the immune cell infiltrate, and outcomes do not correlate with baseline expression of PD-L1. Longer follow up and further mechanistic studies are underway. Clinical trial information: NCT02339324.

Elevated pretreatment serum IL-8 and PD-L1 and overall survival in a phase III randomized advanced pancreatic cancer clinical trial

4131

Background: We previously reported the prognostic and predictive utility of pretreatment serum PD-L1 in the CCTG MA.31 serum bank (SABCS 2018, abstr PD3-10). IL-8 (CXCL8) is a pro-inflammatory cytokine that binds to CXCR1 and CXCR2 and promotes tumor immune escape and progression. High serum IL-8 levels are associated with poor prognosis in many cancers, and have recently been reported to predict for reduced OS to nivolumab in lung cancer and melanoma (ASCO 2018, abstr #3025). In this study, we retrospectively evaluated combined pretreatment serum IL-8 and PD-L1 on overall survival (OS) from a phase III randomized pancreatic cancer trial of first-line therapy (octreotide + 5-FU vs. 5-FU) that had reported no significant OS difference between treatment arms. Methods: This study had 147 patients with serum available for this retrospective biomarker analysis from an advanced pancreatic cancer phase III clinical trial.TheELLA immunoassay platform (ProteinSimple, San Jose, CA) was utilized to quantitate serum levels of IL-8 and PD-L1. Kaplan-Meier life table analysis was used to correlate serum biomarkers with overall survival (OS). Results: In univariate analysis, pretreatment serum IL-8 was a significant biomarker as a continuous variable (HR = 1.004; p = 0.012) and trended significant at the median cutpoint (HR = 1.379; p = 0.098) for OS, however serum PD-L1 was not significant at any cutpoint. When serum PD-L1 and IL-8 levels were analyzed as combined biomarkers (median cutpoints), the serum IL-8 high / PD-L1 high cohort had a significantly shorter OS vs the serum IL-8 low / PD-L1 low cohort (HR = 1.816; p = 0.017). Conclusions: In this phase III randomized clinical trial in advanced pancreatic cancer, pretreatment serum IL-8 was a significant biomarker for OS, but serum PD-L1 was not. Higher combined pretreatment serum levels of PD-L1 and IL-8 (both biomarkers high vs. both low) were prognostic for reduced OS in this phase III pancreatic cancer trial. Further study of circulating IL-8 and PD-L1 is warranted in pancreatic cancer for evaluation of targeted and investigational therapies, including the immune checkpoint inhibitors and anti-IL8 therapy.

Utility of concurrent immunoradiation for locally advanced and/or medically inoperable melanoma and Merkel cell carcinoma

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Background: Melanoma and Merkel Cell Carcinoma (MCC) are aggressive cutaneous malignancies with poor responses to cytotoxic chemotherapy. The use of immune checkpoint inhibitors (ICI) has substantially improved outcomes in metastatic disease and in the neoadjuvant setting. Addition of concurrent radiation therapy (RT) can augment the response of ICI, however there are little data on this combined approach as a neoadjuvant or non-operative strategy. Methods: We retrospectively analyzed outcomes of patients who received RT combined with an ICI against PD1, PD-L1, CTLA-4, or dual targets as neoadjuvant or definitive non-operative management for non-polymetastatic disease at our center from 2012 to 2018. Results: This study analyzed 14 patients, 7 males and 7 females, with a median age of 75 years. There were 10 patients with melanoma and 4 patients with MCC. Among them, 9 patients had stage III disease and 5 patients had oligometastatic disease. Prior treatments included surgery (71%), radiation (21%), and immunotherapy (21%) comprising interferon alpha (1), intralesional BCG (1), and Nivolumab (1). The ICI used were Pembrolizumab (5), Nivolumab (2), Avelumab (2), Ipilumumab (4) and Ipilumumab + Nivolumab (1). Immune related adverse events were seen in 8 patients and included endocrine (5), skin (4), and gastrointestinal (2) toxicity, majority of which were grade 1. Both grade 3 dermatitis and colitis were seen in 2 patients, and 1 patient had grade 3 colitis. There was 1 patient with grade 1 radiation dermatitis. Following concurrent ICI + RT, 4 patients who did not achieve a complete response (CR) at the irradiated site underwent surgical resection with no postoperative complications. An objective response at the irradiated site was seen in 13 (93%) patients, and 12 (86%) patients achieved a CR outside the radiated field. At the time of last follow up, 10 patients remain alive, of which 8 patients are in sustained complete remission. Conclusions: Concurrent use of ICI + RT was a safe approach in patients with locally advanced or medically inoperable melanoma and MCC with potential for durable complete remissions in the majority. Prospective studies are warranted to further validate this approach.

Write to recover: The impact of group led creative writing on behavioral health outcomes in cancer patients

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Background: The diagnosis of cancer can adversely affect mental wellbeing. In addition to treating cancer, the emotional wellbeing of patients must simultaneously be addressed. A previous pilot exploring the feasibility of creative writing workshop (CWW) in cancer patients showed apositive effect on patients’ mental health. Methods: To longitudinally evaluate the efficacy of CWW on mood, we conducted a phase II study with cancer patients (any stage, any cancer type); randomized 2:1 to CWW vs. active control (AC). Patients in the CWW arm attended at least 4, 1.5-hour bi-monthly CWW x 8 wks, whereas AC patients completed independent writing at home with the help of a book (bi-monthly x 8wks). We used validated tools, [Emotional Thermometer Scales (ETS), PHQ-9, GAD-7] to assess changes in overall mood, depression, and anxiety. Primary end point: a) ETS scores before and after intervention b) Changes in depression and anxiety based on PHQ-9 and GAD-7 scores. We present results from ETS scores. Descriptive statistics were generated for these quantitative scales measured in each group, pre and post intervention. Comparisons between groups (gp) were made using Wilcoxon Rank-sum tests. All tests were two sided and the statistical significance level used was 0.05. Results: Amongst evaluable patients, N of 50 (demographics in table below), twenty-six patients in the CWW gp attended at least one class and 19 attended at least 4 classes. Patients in CWW showed significant mood improvement vs. AC when comparing the final overall ETS (p=0.0063). Three of the five sub-scale ETS scores were significantly lower for the CWW vs. AC gp: anxiety (p=0.0027), depression (p=0.0009), and anger (p=0.0027). Conclusions: Group led CWW have a positive effect on mood. Our results suggest potential therapeutic benefit of this intervention on the emotional wellbeing of cancer patients. Larger studies are needed to evaluate the effect of CWW in cancer patients. Clinical trial information: NCT03536702. [Table: see text]

Small cell bladder carcinoma: Single institution experience

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Background: Small cell bladder carcinoma (SCBC) is an uncommon neuroendocrine tumor with poor prognosis. Treatment has largely been derived from data for small cell lung carcinoma and typically includes a multimodality approach with chemotherapy (chemo) serving as the backbone along with radical cystectomy (RC), and radiation (RT). Prior studies have demonstrated conflicting results regarding survival benefit. Methods: We performed a retrospective chart review of patients with SCBC between 2003 and 2017. We compared baseline patient characteristics and patient outcomes. OS was measured from time of initial diagnosis to death or last follow-up. Subgroup analyses were performed between patients treated with chemoRT vs. chemoRC using Fisher’s exact test for categorical variables, and nonparametric Wilcoxon Rank-Sum test for quantitative variables. Kaplan-Meier analyses were done on OS and RFS. All tests were two-sided and statistical significance level of 0.05 was used. Results: We identified a total of 31 patients with SCBC; 28 were non-metastatic and 3 were metastatic. Of the non-metastatic, 14 received chemoRT and 4 received chemoRC. The median age was 70; M:F ratio was 17:1. The median RFS in chemoRT patients was 3.05 yrs, and in chemoRC, RFS was not reached (p = 0.18). The median OS in chemoRT and chemoRC were 10.1 and 10.7 yrs respectively (p = 0.38). The overall median OS for SCBC was 2.45 yrs. Conclusions: There were no statistically significant differences in regards to median RFS or OS between the chemoRT and chemoRC patients, but this analysis was limited by the small sample size. However, the median OS in non-metastatic SCBC patients who received treatment with curative intent (chemoRT or chemoRC) was noticeably longer than that of all SCBC patients. This median OS is also longer than anticipated with small cell lung cancer and suggests that SCBC has a different natural history. These findings warrant further investigation.

Alterations of DNA damage response (DDR) genes correlate with favorable response and overall survival (OS) in anti-PD-1/PD-L1-treated advanced urothelial cancer (UC)

438

Background: DDR gene alterations may contribute to higher tumor mutational burden (TMB) via genomic instability in addition to APOBEC mutagenesis. We previously showed that ATM mutations correlated with shorter OS in UC, while Teo et al. showed patients (pts) with DDR alterations benefited from PD-1/PD-L1 blockade in advanced UC. Here, we aimed to validate those findings and further explore the prognostic role of ATM mutations in advanced UC treated with anti-PD-1/PD-L1 agents. Methods: The study included 53 pts who had FoundationOne tumor tissue genomic sequencing and anti-PD-1/PD-L1 therapy. Fisher exact test was used to test difference in objective response rate (ORR). OS was measured from time of initial UC diagnosis and Cox proportional hazard regression analysis was performed to calculate the hazard ratio (HR) and 95% confidence interval (CI). Results: The cohort had a median age of 66 (range 21–81) with 34% females and 64.2% platinum-based chemotherapy. DDR alterations (including ATM) were present in 49.1% pts (26/53) and favored a higher ORR (37.5% vs. 23.1%, p = 0.26). Compared with those without DDR alterations, pts with DDR alterations (excluding ATM) seemed to have longer OS, although significance was not reached likely due to a short follow-up time (HR = 0.53, 95% CI 0.20–1.38, p = 0.19). ATM alterations seemed to favor higher response rate to PD-1/PD-L1 blockade (ORR, 40% vs. 28.9%, p = 0.6), but was associated with significantly shorter OS (HR = 5.7, 95% CI 1.65–19.74, p = 0.006) in overall pts and in subgroups with/without platinum-based chemotherapy (data not shown). Pts with ≥ 3 DDR alterations (including ATM) had substantial higher TMB (13.9–72.2 perMb, median 22.6) and benefited the most from PD-1/PD-L1 blockade with 80% ORR vs. 24.4% ORR in pts with < 3 DDR alterations. Conclusions: Our study supported that DDR alterations are associated with higher response rate and prolonged OS in advanced UC pts receiving anti-PD-1/PD-L1 agents, likely from impact on TMB. However, ATM alterations correlated with poor prognosis also in those pts. Further studies are needed to assess the clinical utility of DDR alterations in directing therapies in UC.

Prognostic value of genomic alterations in DNA damage response (DDR) genes in relapsed/advanced bladder cancer (BCa)

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Background: DDR defects play an important role in tumorigenesis, progression, treatment response and outcomes of BCa. We previously showed DDR mutations were associated with better prognosis in relapsed/advanced (TxN2-3M0-1) BCa. In this study, we aimed to update and validate our findings in 3 independent datasets. Methods: 81 BCa patients (pts) who had FoundationOne tumor tissue genomic sequencing (315 cancer-related genes) were used as discovery dataset. Validation dataset 1 consisted of additional 91 pts with FoundationOne test. Validation dataset 2 consisted of 129 relapsed/advanced pts from TCGA BCa cohort. Overall survival (OS) was measured from time of initial BCa diagnosis to death or last follow-up. Cox proportional hazard regression analysis was performed to calculate the hazard ratio (HR) and 95% confidence interval (CI). Logistic regression analysis was performed to calculate odds ratio (OR) and 95% CI. A panel of 32 DDR genes (excluding ATM) were used for analyses because ATM mutation was a negative prognostic factor in our prior study. Results: DDR mutations were present in 76.5% (62/81), 40.7% (37/91) and 51.2% (66/129) pts of the 3 datasets. They were associated with longer OS (adjHR = 0.39, 95% CI 0.21–0.73, p = 0.003) in the discovery dataset, which were confirmed in two validation datasets (Validation 1: adjHR = 0.51, 95% CI 0.26–1.03, p = 0.059; Validation 2: adjHR = 0.62, 95% CI 0.39–0.97, p = 0.038). There was a trend for longer OS with increased number of DDR mutations in individual pts. Pts carrying ≥3 DDR mutations had the best prognosis (data not shown). In 144 cisplatin or carboplatin-treated pts pooled from the 3 cohorts, pts with DDR mutations were more likely to have objective response (OR = 1.81, 95% CI 0.85–3.92 for any DDR mutations; OR = 3.65, 95% CI 0.91–14.7 for ≥3 DDR mutations) and longer overall survival (HR = 0.61, 95% CI 0.38–0.98 for any DDR mutations; HR = 0.49, 95% CI 0.19–1.27 for ≥3 DDR mutations). Conclusions: DDR mutations (excluding ATM gene and especially ≥3) correlated with better outcomes in relapsed/advanced BCa. Further exploration of the deleterious nature and functional impact of alterations is critical along with prospective validation in ongoing trials.

ATM mutation is associated with shorter overall survival in relapsed/advanced urothelial cancer

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Background: Somatic mutations of ATM are frequently found in UC and have been associated with a better response to cisplatin-based neoadjuvant chemotherapy. However, we previously showed ATM mutations were associated with a short survival in UC (PMID: 29682192 ). In this study, we focused on prognostic values of mutations in ATM in tumors of patients with relapsed or advanced (TxN2-3M0-1) UC through three independent datasets. Methods: 81 UC pts who underwent FoundationOne genomic sequencing (315 cancer-related genes) were used as a discovery dataset. Results were then validated in additional 91 pts with UC who received FoundationOne test (collected separately) and 129 relapsed/advanced UC patients selected from 412 TCGA bladder cohort. Fisher Exact test was used to determine difference of ATM mutation rates. Logistic regression analysis was performed to calculate odds ratio (OR) and 95% confidence interval (CI). Overall survival (OS) was measured from time of initial diagnosis and Cox proportional hazard regression analysis was performed to calculate the hazard ratio (HR) and 95% CI. Results: The median ages of the 3 cohorts were 65 (44–84), 65 (21–91) and 67 (45–-90). The majority of pts were Caucasians (86.4%, 75.8% and 81.4%) and ever smokers (77.8%, 67% and 76.7%). ATM mutations were present in 14.8% (12/81), 11% (10/91) and 6.2% (8/129) of the three cohorts (Fisher Exact, p = 0.118). In all three groups of pts, ATM mutations consistently correlated with a significantly shorter OS (Discovery: HR = 2.25, 95% CI, 1.03–4.89, p = 0.041; Validation 1: HR = 3.15, 95% CI, 1.17–8.44, p = 0.023; and Validation 2: HR = 2.17, 95% CI, 0.99–4.75, p = 0.051). In 144 pts treated with cisplatin or carboplatin pooled from the three cohorts, ATM mutations correlated with a non-significantly higher objective response rate (OR = 1.54, 95% CI 0.44–5.35, p = 0.5), but were still associated with a poorer survival (HR = 1.95, 95% CI 1.00–3.83, p = 0.05). Conclusions: These results suggest that ATM mutations may be considered as a negative prognostic biomarker in relapsed/advanced UC pts. Further studies are required to determine the underlying mechanisms.

Effect of creative writing on mood in patients with cancer

OBJECTIVE

To determine the feasibility of conducting creative writing workshops (CWW) for patients with cancer to promote improvement in mood.

METHOD

We piloted a prospective study to determine the feasibility of conducting CWW over a 4-week period. Patients were randomised 2:1 to either an intervention arm (IA) or to standard of care (SOC). Patients in the IA attended four 2-hour long weekly CWW × 4 weeks, whereas those receiving SOC did not participate in the CWW. We used a validated emotion thermometer scale (ETS) to assess changes in patient's mental health before and after intervention. Patients with metastatic or unresectable cancer were included. PRIMARY ENDPOINT: (1) Feasibility and (2) mood scores before and after CWW using ETS.

RESULTS

A total of 16 patients were enrolled: 11 in the IA vs 5 in SOC. Seven out of 11 (63%) patients enrolled in the IA attended at least 75% of classes. Patients in the IA showed a trend towards mood improvement relative to the SOC when comparing initial and final ETS scores. Within the IA group significantly lower postclass total ETS scores were observed relative to preclass ETS scores. Also, a significant decreasing trend over time was observed in the preclass total ETS scores for participants in the IA group.

CONCLUSIONS

It is feasible for patients with cancer to attend CWW. Our results also show a positive effect on mood in the CWW arm. Further prospective clinical studies are needed to evaluate the effect of this intervention in patients with cancer.

Abstract PD3-10: Higher serum PD-L1 predicts for increased overall survival to lapatinib vs trastuzumab in the phase 3 CCTG MA.31 trial

Background: In the CCTG (Canadian Clinical Trials Group) MA.31 randomized phase 3 trial, the trastuzumab-taxane combination led to longer PFS than lapatinib-taxane in HER2-positive metastatic breast cancer (MBC). We previously reported the prognostic utility of pretreatment serum PD-L1 in the trastuzumab arm of MA.31 (ASCO 2018, #1031), and here we evaluate serum PD-L1 in the lapatinib arm, and in the whole trial. Higher serum PD-L1 has been reported to be associated with reduced response to treatment with the immune checkpoint inhibitors in melanoma and lung cancer.

Methods: MA.31 accrued 652 centrally and/or locally-identified HER2-positivepatients; 186 in the trastuzumab arm, and 202 in the lapatinib armhad pretreatment serum available. TheELLA immunoassay platform (ProteinSimple, San Jose, CA) was used to quantitate serum PD-L1. Step-wise forward Cox multivariate analysis was used for PFS and OS, and testing for treatment-biomarker interaction was based on the local partial-likelihood method (Liu Y, Jiang W, and Chen BE, Statistics in Medicine 34, 3516-3530, 2015).

Results: In the total study population, pretreatment serum PD-L1 concentration had a median of 86.2 pg/ml, and 25% and 75% interquartiles of 64.1 and 134.3 pg/ml, respectively. In univariate analysis in the whole trial, and within both treatment arms, serum PD-L1 was not a significant biomarker for PFS. For OS, higher serum PD-L1 (as a continuous variable) was significant for shorter OS within the trastuzumab arm (HR=3.84, p=0.04), but was not associated with OS in the lapatinib arm (p=0.37). In the whole trial, in multivariate analysis for OS [15 covariates included: age, race, ECOG status, anthracyclines, other chemo, endocrine, radio, other prior adjuvant therapy, disease status, ER status, PR status, Ki67 (log transformed), CK5, EGFR, treatment arm, and serum PD-L1 (with median cut point)], serum PD-L1 remained a significant independent covariate (HR= 2.27, p= 0.001 (Table).There was significant interaction between treatment arm and continuous serum PD-L1 (Bootstrap method, p=0.0025); above 214.2 pg/ml serum PD-L1 (89% percentile), higher pretreatment serum PD-L1 was associated with a shorter OS to trastuzumab treatment, but longer OS to lapatinib treatment.

Conclusions: In the CCTG MA.31 trial, serum PD-L1 was a significant predictive factor: higher pretreatment serum PD-L1 was associated with a shorter OS to trastuzumab treatment, but longer OS to lapatinib treatment. Immune evasion may decrease the effectiveness of trastuzumab therapy. Further evaluation of elevated serum PD-L1 in the advanced breast cancer setting is warranted to identify HER2-positive MBC patients who may benefit from novel immune-targeted therapies in addition to trastuzumab.

Multivariate Analysis (whole trial): Significant Independent CovariatesCovariateP-ValueHRLower 95% CIHigher 95% CISerum PD-L1 (pretreatment) (&gt;median vs &lt;median)0.0012.271.403.68EGFR Status (continuous IHC score)0.0031.0121.0041.019Other Chemotherapy (yes vs no)0.0081.911.193.07Treatment Arm (trastuzumab vs. lapatinib)0.0100.530.330.86ECOG Performance Status (0 vs 1 or 2)0.0250.590.370.94Ki67 (log)0.0461.451.0062.081

Citation Format: Moku PR, Shepherd LE, Ali SM, Leitzel K, Parulekar WE, Zhu L, Virk S, Nomikos D, Aparicio S, Gelmon KA, Drabick JJ, Cream L, Halstead SE, Umstead T, Mckeone D, Maddukuri A, Polimera HV, Ali A, Poulose J, Pancholy N, Spiegel H, Nagabhairu V, Chen BE, Lipton A. Higher serum PD-L1 predicts for increased overall survival to lapatinib vs trastuzumab in the phase 3 CCTG MA.31 trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD3-10.

Eomes+T-betlow CD8+ T Cells Are Functionally Impaired and Are Associated with Poor Clinical Outcome in Patients with Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a devastating blood cancer with poor prognosis. Immunotherapy targeting inhibitory pathways to unleash the antileukemia T-cell response is a promising strategy for the treatment of leukemia, but we must first understand the underlying molecular mechanisms. Eomesodermin (Eomes) and T-bet are both T-box transcription factors that regulate CD8⁺ T-cell responses in a context-specific manner. Here, we examined the role of these transcription factors in CD8⁺ T-cell immunity in AML patients. We report that the frequency of Eomes⁺T-bet^low CD8⁺ T cells increased in newly diagnosed AML. This cell subset produced fewer cytokines and displayed reduced killing capacity, whereas depletion of Eomes by siRNA reversed these functional defects. Furthermore, Eomes bound the promoter of T-cell immunoglobulin and ITIM domain (TIGIT) and positively regulated the expression of this inhibitory receptor on patient-derived T cells. A high frequency of Eomes⁺T-bet^low CD8⁺ T cells was associated with poor response to induction chemotherapy and shorter overall survival in AML patients. These findings have significant clinical implications as they not only identify a predictive and prognostic biomarker for AML, but they also provide an important target for effective leukemia therapeutics. SIGNIFICANCE: These findings reveal that a high frequency of Eomes⁺T-bet^low CD8⁺ T cells predicts poor clinical outcome in AML and that targeting Eomes may provide a therapeutic benefit against AML.

Schweinfurthin natural products induce regression of murine melanoma and pair with anti-PD-1 therapy to facilitate durable tumor immunity

Metastatic melanoma is a significant clinical problem with a 5-year survival rate of only 15-20%. Recent approval of new immunotherapies and targeted inhibitors have provided much needed options for these patients, in some cases promoting dramatic disease regressions. In particular, antibody-based therapies that block the PD-1/PD-L1 checkpoint inhibitory pathway have achieved an increased overall response rate in metastatic melanoma, yet durable response rates are reported only around 15%. To improve the overall and durable response rates for advanced-stage melanoma, combined targeted and immune-based therapies are under investigation. Here, we investigated how the natural products called schweinfurthins, which have selective anti-proliferative activity against many cancer types, impact anti-(α)PD-1-mediated immunotherapy of murine melanomas. Two different compounds efficiently reduced the growth of human and murine melanoma cells in vitro and induced plasma membrane surface localization of the ER-resident protein calreticulin in B16.F10 melanoma cells, an indicator of immunogenic cell death. In addition, both compounds improved αPD-1-mediated immunotherapy of established tumors in immunocompetent C57BL/6 mice either by delaying tumor progression or resulting in complete tumor regression. Improved immunotherapy was accomplished following only a 5-day course of schweinfurthin, which was associated with initial tumor regression even in the absence of αPD-1. Schweinfurthin-induced tumor regression required an intact immune system as tumors were unaffected in NOD scid gamma (NSG) mice. These results indicate that schweinfurthins improve αPD-1 therapy, leading to enhanced and durable anti-tumor immunity and support the translation of this novel approach to further improve response rates for metastatic melanoma.

SD-101 in Combination with Pembrolizumab in Advanced Melanoma: Results of a Phase Ib, Multicenter Study

PD-1 inhibitors are approved for treating advanced melanoma, but resistance has been observed. This phase Ib trial evaluated intratumoral SD-101, a synthetic CpG oligonucleotide that stimulates Toll-like receptor 9 (TLR9), in combination with pembrolizumab in patients with unresectable or metastatic malignant melanoma. The most common adverse events related to SD-101 were injection-site reactions and transient, mild-to-moderate "flu-like" symptoms. Among the 9 patients naïve to anti-PD-1 therapy, the overall response rate (ORR) was 78%. The estimated 12-month progression-free survival rate was 88%, and the overall survival rate was 89%. Among 13 patients having prior anti-PD-1 therapy, the ORR was 15%. RNA profiling of tumor biopsies demonstrated increased CD8⁺ T cells, natural killer cells, cytotoxic cells, dendritic cells, and B cells. The combination of intratumoral SD-101 and pembrolizumab was well tolerated and induced broad immune activation in the tumor microenvironment with durable tumor responses in both peripheral and visceral lesions.Significance: These early data demonstrate that the combination of pembrolizumab with intratumoral SD-101 is well tolerated and can induce immune activation at the tumor site. Combining an intratumoral TLR9 innate immune stimulant with PD-1 blockade can potentially increase clinical efficacy with minimal additional toxicity relative to PD-1 blockade alone. Cancer Discov; 8(10); 1250-7. ©2018 AACR. This article is highlighted in the In This Issue feature, p. 1195.

Abstract CT139: Durability of responses to the combination of SD-101 and pembrolizumab in advanced metastatic melanoma: Results of a phase Ib, multicenter study

Background: This phase 1b trial evaluates the safety and antitumor efficacy of the combination of SD-101, a synthetic CpG-oligonucleotide that stimulates Toll-like receptor 9 (TLR9), and pembrolizumab in patients with recurrent Stage IIIC/IV malignant melanoma.

Methods: Dose escalation of SD-101 used a modified 3+3 design. SD-101 was injected in a single tumor lesion (weekly x 4 doses then every 3 weeks x 7 doses over 6 months) at 1, 2, 4, or 8 mg and pembrolizumab was administered intravenously at 200 mg every 3 weeks up to 2 years. Tumor responses were assessed per investigator using RECIST v1.1 taking into account both injected and non-injected lesions.

Results: Of the 22 patients, 9 were naïve to anti-PD-1/L1 therapy at baseline and 13 had progressive disease while receiving prior anti-PD-1/L1 therapy. Treatment was well tolerated with no Grade 3 or higher treatment-related AEs in longer term follow up. Among the 9 patients who were anti-PD-1/L1 naïve, best objective responses were CR: 2, PR: 5, PD: 1, not evaluated [NE]: 1. Median PFS, duration of response, and OS have not been reached. Estimated 12 month PFS was 88% and OS was 89%. After a median of 18 months of follow-up, 86% of responses were ongoing. One patient with a PR developed progressive disease after 20 months of treatment. Among patients who had received prior anti-PD-1/L1 therapy, best objective responses were PR: 2, SD: 5, PD: 5, NE: 1. One patient with stable disease and 1 patient with a PR continued on combination therapy without progression for at least 10.5 months. The other 10 patients developed progressive disease ranging from 1.5 to 8 months after enrollment. Percent change in tumor size from baseline in injected and non-injected lesions will also be presented.

Conclusion: These early results suggest that combining an intratumoral TLR9 innate immune stimulant with PD-1 blockade can potentially provide more clinical responses that are meaningfully durable than PD-1 blockade alone based on historical data.

Citation Format: Antoni Ribas, Theresa Medina, Shivaani Kummar, Asim Amin, Joseph J. Drabick, Minal Barve, Gregory Daniels, Deborah L. Wong, Emmett V. Schmidt, Abraham C. Leung, Robert Janssen. Durability of responses to the combination of SD-101 and pembrolizumab in advanced metastatic melanoma: Results of a phase Ib, multicenter study [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 CT139.

ATM/RB1 mutations predict shorter overall survival in urothelial cancer

BACKGROUND

Mutations of DNA repair genes, e.g. ATM/RB1, are frequently found in urothelial cancer (UC) and have been associated with better response to cisplatin-based chemotherapy. Further external validation of the prognostic value of ATM/RB1 mutations in UC can inform clinical decision making and trial designs.

RESULTS

In the discovery dataset, ATM/RB1 mutations were present in 24% of patients and were associated with shorter OS (adjusted HR 2.67, 95% CI, 1.45-4.92, p = 0.002). There was a higher mutation load in patients carrying ATM/RB1 mutations (median mutation load: 6.7 versus 5.5 per Mb, p = 0.072). In the validation dataset, ATM/RB1 mutations were present in 22.2% of patients and were non-significantly associated with shorter OS (adjusted HR 1.87, 95% CI, 0.97-3.59, p = 0.06) and higher mutation load (median mutation load: 8.1 versus 7.2 per Mb, p = 0.126).

MATERIALS AND METHODS

Exome sequencing data of 130 bladder UC patients from The Cancer Genome Atlas (TCGA) dataset were analyzed as a discovery cohort to determine the prognostic value of ATM/RB1 mutations. Results were validated in an independent cohort of 81 advanced UC patients. Cox proportional hazard regression analysis was performed to calculate the hazard ratio (HR) and 95% confidence interval (CI) to compare overall survival (OS).

CONCLUSIONS

ATM/RB1 mutations may be a biomarker of poor prognosis in unselected UC patients and may correlate with higher mutational load. Further studies are required to determine factors that can further stratify prognosis and evaluate predictive role of ATM/RB1 mutation status to immunotherapy and platinum-based chemotherapy.