Abstract LB050: Modulation of innate and adaptive immunity in blood and tumor of patients receiving the SHP2 inhibitor RMC-4630

RMC-4630 is a potent, selective, orally bioavailable allosteric inhibitor of SHP2, a central node in the RAS signaling pathway. In preclinical models, SHP2 inhibition not only directly inhibited tumor growth through suppression of tumor-intrinsic RAS signaling, but also resulted in transformation of the tumor immune microenvironment, characterized by an increase in CD8+T cell infiltrates and selective depletion of pro-tumorigenic M2 macrophages.

In this study, we evaluated pharmacodynamic biomarkers in blood and tumors from patients in the RMC-4630 phase I monotherapy clinical trial (NCT 03634982) by using flow cytometry and immunohistochemistry (IHC). Safety, PK and efficacy data are reported in a separate abstract.

Longitudinal analysis of immune cell phenotyping in blood was conducted in 35 patients. There was a trend for lower pre-study monocytic myeloid-derived suppressor cell (mMDSC) to be associated with a better clinical outcome on RMC-4630 therapy. While the proportion of circulating T cell and B cell populations did not change, both blood mMDSC and total monocytes were significantly reduced during RMC-4630 administration. Furthermore, tumor volumes changes, and the proportion of patients with SD versus PD, positively correlated with the ratio of mMDSCs to total monocytes on RMC-4630 treatment.

Inhibition of pERK was observed in a subset of patients. Three paired tumor biopsies from efficacy-evaluable patients, including 1 PR, 1 SD and 1 PD, were available for tumor microenvironment analysis by multiplexed-IHC assays. Increase in tumor infiltrating T cells in the tumors of one patient with a PR and another with SD was observed on RMC-4630 therapy. Inhibition of tumor PD-L1 expression and a decrease in M2 macrophages was also observed on treatment in the tumor biopsy of the PR patient.

Collectively, the preliminary clinical biomarker data supports the preclinical observations that SHP2 inhibition with RMC-4630 modulates both innate and adaptive anti-tumor immunity.

Citation Format: Ariel Yung-Chia Chen, Eric Haura, Jose Pacheco, Marianna Koczywas, Michael Gordon, Susanna Ulahannan, Howard A. Burris, Sai-Hong Ignatius Ou, Judy S. Wang, Jonathan W. Riess, Caroline McCoach, Anna Capasso, Elsa Quintana, Josie Hayes, Richa Dua, Bojena Bitman, Martha Guerra, Hongfang Wang, Xiaolin Wang, Pasi A. Janne. Modulation of innate and adaptive immunity in blood and tumor of patients receiving the SHP2 inhibitor RMC-4630 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB050.

Abstract LB054: Confirmation of target inhibition and anti-tumor activity of the SHP2 inhibitor RMC-4630 via longitudinal analysis of ctDNA in a phase 1 clinical study

RMC-4630 is a potent, selective, orally bioavailable allosteric inhibitor of SHP2, a central node in the RAS signaling pathway. Preclinical data have demonstrated that RMC-4630 can shrink tumors carrying certain mutations in the RAS pathway such as KRASG12C, NF1LOF, and BRAFClass3. Longitudinal circulating tumor DNA (ctDNA) was isolated from blood using GuardantOMNI in 80 patients with relapsed/refractory solid tumors in the phase 1 dose-escalation trial of RMC-4630 (NCT03634982) to characterize and confirm RAS pathway mutations and to evaluate molecular responses in patients receiving RMC-4630 monotherapy. Safety, PK and efficacy findings from this study are reported in a separate abstract. 78 of 80 patients had baseline somatic mutations detected in plasma, of which 60 were either KRASG12X, NF1LOF, or BRAFClass3; 48 of these 60 patients also had on-treatment ctDNA assessments and these patients constitute the population reported here. 9 of 48 patients (19%) had KRASG12C detected at baseline, available scan results and a ctDNA sample after 4 weeks of receiving RMC-4630. A decrease in KRASG12C variant allele frequency (VAF) was detected in 5/9 patients (56%) with clearance in 1 patient with a partial response. Decrease in KRASG12C VAF was associated with change in tumor volume (PCC=0.85, p=0.008), preceding scan results by approximately 1 month, suggesting that change in KRASG12C VAF may be an early measure of drug activity or possibly response. 5 of 48 patients (10%) had NF1LOF detected at baseline. A decrease, or stability in NF1LOF VAF on treatment compared to baseline was detected in 4 (80% of all NF1LOF patients). The decrease in NF1LOF VAF was not associated with change in tumor volume and may represent effects of RMC-4630 on a subclone harboring NF1LOF. One patient had a detectable BRAFClass3 mutation at baseline, which decreased in VAF on treatment compared to baseline. Of the remaining patients there were 12 KRASG12D, 9 KRASG12V and other KRASG12X. The majority progressed with an increase in VAF of all mutations including KRASG12X, suggesting that the KRASG12X-containing clone is responsible for escape from single agent RMC-4630. In most instances the increase in KRASG12X VAF in blood preceded determination of clinical progression. Longitudinal assessment of ctDNA indicates that some patients with RAS-addicted tumors undergo a molecular response on treatment with the SHP2 inhibitor RMC-4630.

Citation Format: Josie L. Hayes, Marianna Koczywas, Sai-Hong Ignatius Ou, Pasi A. Janne, Jose M. Pacheco, Susanna Ulahannan, Judy S. Wang, Howard A. Burris, Jonathan W. Riess, Caroline McCoach, Michael S. Gordon, Anna Capasso, Ariel Chen, Richa Dua, Bojena Bitman, Martha Guerra, Hongfang Wang, Xiaolin Wang, Eric Haura. Confirmation of target inhibition and anti-tumor activity of the SHP2 inhibitor RMC-4630 via longitudinal analysis of ctDNA in a phase 1 clinical study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB054.

Abstract PS11-29: A phase 2 study evaluating orteronel, an inhibitor of androgen biosynthesis, in patients with androgen receptor (AR)-expressing metastatic triple-negative breast cancer (TNBC)

Background: Treatment options for TNBC are limited by the lack of estrogen and progesterone receptors as well as the absence of HER2 overexpression. AR is present in all breast cancer subtypes and up to 40% of TNBC have AR overexpression (AR+). Thus AR positivity in TNBC represents a potential targetable signaling pathway. Preclinical studies demonstrated that AR modulation inhibits cell proliferation, and clinical activity with anti-androgen monotherapy has been reported in breast cancer. Orteronel is a novel, oral, selective, nonsteroidal inhibitor of 17, 20-lyase, a key enzyme in androgen biosynthesis under evaluation as a potential therapeutic strategy in hormone-sensitive cancers. In this phase 2 study, we evaluated androgen blockade with single agent orteronel in AR+ metastatic breast cancer (MBC). Methods: Male or female pts with AR+ MBC (≥10% staining by central immunohistochemistry) were eligible. Pts were grouped into 2 cohorts for analysis: Cohort 1-TNBC (AR+/ER-/PR-/HER2-) and Cohort 2-ER+ (AR+/ER+/HER2 +/-). Results in Cohort 2 (ER+) have been previously reported; here we report results in the AR+ TNBC cohort. TNBC pts must have been previously treated with standard therapy (1-3 chemotherapy regimens for MBC). All pts received 300 mg orteronel PO BID over a 4 week cycle and underwent response assessment every 2 cycles. Treatment continued until disease progression or unacceptable toxicity. The hypothesized response rate for pts with previously treated metastatic AR+ TNBC was 11%. Results: From 7/2014 to 2/2019 a total of 26 AR+ TNBC pts were enrolled on cohort 1. The trial closed early due to slow accrual. Median age was 57 years (range, 33-92); 96% ECOG 0-1; all pts had ≥ 1 prior chemotherapy; 42% prior targeted therapy; 8% prior immunotherapy. All tumors were ER and PR negative per institutional standards. PI3K was mutated in 16% (3/19) tumors tested and 65% (13/20) were PTEN-negative. Median duration of treatment was 8 weeks (range 0.7-35.7) with 15% of pts on treatment ≥ 6 months (mo). All pts have discontinued treatment, 85% due to disease progression, and 15% due to AEs. Nausea and fatigue [8 pts each (31%)] were the most common AEs noted. G 3/4 AEs included hypertension, increased amylase and lipase [2 pts each (8%)] with 4 patients reporting SAEs (G2 pneumonitis, G2 chest pain and G2 peripheral edema, G4 prolonged QT and G4 hypokalemia). The ORR was 4% and DCR was 15%. Median PFS was 2.0 mo and median OS was 10.2 mo. Conclusions: Orteronel monotherapy was well tolerated but demonstrated limited clinical activity in this heavily pre-treated metastatic AR+ TNBC patient population. As novel AR targeting agents are being developed, future studies are needed to identify AR+ breast cancer patients most likely to benefit from AR inhibition.

Citation Format: Denise A Yardley, Robyn R Young, Kerin B Adelson, Andrea L Silber, Michael D Kommor, Jose E Najera, Davey B Daniel, Nancy W Peacock, Mythili Shastry, John D Hainsworth, Howard A Burris, III. A phase 2 study evaluating orteronel, an inhibitor of androgen biosynthesis, in patients with androgen receptor (AR)-expressing metastatic triple-negative breast cancer (TNBC) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS11-29.

American Society of Clinical Oncology Road to Recovery Report: Learning From the COVID-19 Experience to Improve Clinical Research and Cancer Care

This report presents the American Society of Clinical Oncology's (ASCO's) evaluation of the adaptations in care delivery, research operations, and regulatory oversight made in response to the coronavirus pandemic and presents recommendations for moving forward as the pandemic recedes. ASCO organized its recommendations for clinical research around five goals to ensure lessons learned from the COVID-19 experience are used to craft a more equitable, accessible, and efficient clinical research system that protects patient safety, ensures scientific integrity, and maintains data quality. The specific goals are: (1) ensure that clinical research is accessible, affordable, and equitable; (2) design more pragmatic and efficient clinical trials; (3) minimize administrative and regulatory burdens on research sites; (4) recruit, retain, and support a well-trained clinical research workforce; and (5) promote appropriate oversight and review of clinical trial conduct and results. Similarly, ASCO also organized its recommendations regarding cancer care delivery around five goals: (1) promote and protect equitable access to high-quality cancer care; (2) support safe delivery of high-quality cancer care; (3) advance policies to ensure oncology providers have sufficient resources to provide high-quality patient care; (4) recognize and address threats to clinician, provider, and patient well-being; and (5) improve patient access to high-quality cancer care via telemedicine. ASCO will work at all levels to advance the recommendations made in this report.

Research Amidst the Pandemic

Description Cancer patients need access to promising investigational therapies, available only through clinical trials, and the emergence of COVID-19 and the resulting pandemic became an emerging threat to fulfilling that need. Many academic medical centers were pausing their clinical research programs, diverting their resources and sheltering their teams. Sarah Cannon, the Cancer Institute of HCA Healthcare, made the decision to stay safe, but stay the course.

First-in-human phase I study of ARV-110, an androgen receptor (AR) PROTAC degrader in patients (pts) with metastatic castrate-resistant prostate cancer (mCRPC) following enzalutamide (ENZ) and/or abiraterone (ABI)

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Background: Proteolysis Targeting Chimera (PROTAC) protein degraders induce selective degradation of targeted proteins by engaging the ubiquitin proteasome system. ARV-110 is an orally bioavailable PROTAC that specifically degrades AR ≥ 95% and achieves anti-tumor activity in ENZ-naïve and -resistant prostate cancer xenograft models. Methods: To define the maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) of ARV-110, pts with ≥ 2 prior therapies for mCRPC, including ENZ and/or ABI, received ARV-110 orally once daily. Dose escalation is per 3+3 design. Endpoints include dose limiting toxicities (DLTs), adverse events (AEs), pharmacokinetics (PK), biomarkers (e.g., AR mutation analysis), RECIST and PSA response. Results: By January 2020, 18 pts were dosed: 35 mg (N = 3), 70 mg (N = 4), 140 mg (N = 8), 280 mg (N = 3). 12 pts received both ENZ and ABI; 14 received prior chemotherapy. 1 of 18 pts experienced a DLT (280 mg) of Grade (Gr) 4 elevated AST/ALT followed by acute renal failure while taking rosuvastatin (ROS). A 2nd pt had Gr 3 AST/ALT with ROS that resolved off ROS, permitting ARV-110 retreatment. ROS plasma concentrations demonstrated significant increases concurrent with AST/ALT elevations in both pts. Subsequently, ROS was prohibited without further ≥Gr 2 AST/ALT AEs. No other related Gr 3/4 AEs were reported. ARV-110 PK was generally dose proportional and at 140 mg reached levels associated with preclinical anti-tumor activity. 15 pts were evaluable for PSA response (excludes 1 pt stopped after 1 dose for early progression and 2 pts initiated 2 weeks before cutoff, all at 140 mg). Of these, 8 pts initiated dosing at ≥140 mg. 2 pts achieved confirmed PSA declines of >50%, both at 140 mg. Prior therapy in both pts included ENZ and ABI, chemotherapy, bicalutamide and radium-223 plus other regimens. 1 pt had 2 AR mutations known to confer ENZ resistance. The 2nd pt also achieved an unconfirmed RECIST partial response (confirmatory scan pending). Both responses were ongoing at data cutoff (8+ and 21+ weeks of treatment). Conclusions: To date, ARV-110 has an acceptable safety profile. Concurrent ROS is now prohibited. MTD has not yet been established; determination of RP2D continues. ARV-110 demonstrates antitumor activity in mCRPC after ENZ/ABI with 2 ongoing confirmed PSA responses, one of which was associated with tumor reduction. Updated data for this first PROTAC in clinical testing will be presented. Clinical trial information: NCT03888612 .

Infigratinib in upper tract urothelial carcinoma versus urothelial carcinoma of the bladder and its association with comprehensive genomic profiling and/or cell-free DNA results

BACKGROUND

Infigratinib (BGJ398) is a potent and selective fibroblast grown factor receptor 1 to 3 (FGFR1-3) inhibitor with significant activity in patients with advanced or metastatic urothelial carcinoma bearing FGFR3 alterations. Given the distinct biologic characteristics of upper tract urothelial carcinoma (UTUC) and urothelial carcinoma of the bladder (UCB), the authors examined whether infigratinib had varying activity in these settings.

METHODS

Eligible patients had metastatic urothelial carcinoma with activating FGFR3 mutations and/or fusions. Comprehensive genomic profiling was performed on formalin-fixed, paraffin-embedded tissues. Blood was collected for cell-free DNA analysis using a 600-gene panel. Patients received infigratinib at a dose of 125 mg orally daily (3 weeks on/1 week off) until disease progression or intolerable toxicity occurred. The overall response rate (ORR; partial response [PR] plus complete response [CR]) and disease control rate (DCR; CR plus PR plus stable disease [SD]) were characterized.

RESULTS

A total of 67 patients were enrolled; the majority (70.1%) had received ≥2 prior antineoplastic therapies. In 8 patients with UTUC, 1 CR and 3 PRs were observed (ORR, 50%); the remaining patients achieved a best response of SD (DCR, 100%). In patients with UCB, 13 PRs were observed (ORR, 22%), and 22 patients had a best response of SD (DCR, 59.3%). Notable differences in genomic alterations between patients with UTUC and those with UCB included higher frequencies of FGFR3-TACC3 fusions (12.5% vs 6.8%) and FGFR3 R248C mutations (50% vs 11.9%), and a lower frequency of FGFR3 S249C mutations (37.5% vs 59.3%).

CONCLUSIONS

Differences in the cumulative genomic profile were observed between patients with UTUC and those with UCB in the current FGFR3-restricted experience, underscoring the distinct biology of these diseases. These results support a planned phase 3 adjuvant study predominantly performed in this population.

Relationship between hyperphosphatemia with infigratinib (BGJ398) and efficacy in FGFR3-altered advanced/metastatic urothelial carcinoma (aUC)

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Background: Infigratinib (BGJ398) is a potent and selective FGFR1–3 inhibitor with significant clinical activity in aUC bearing FGFR3 alterations. A common adverse event is hyperphosphatemia, a class effect associated with FGFR1 inhibition. We sought to better understand the relationship between hyperphosphatemia and response to infigratinib in patients with aUC. Methods: Eligible patients had aUC with activating FGFR3 mutations/fusions and had received prior platinum-based chemotherapy, unless contraindicated. Patients received infigratinib 125 mg orally daily (3w on/1w off) until disease progression or unacceptable toxicity. Calcium and phosphate levels within normal limits were required at enrollment. Efficacy was assessed by overall response rate (ORR) and disease control rate (DCR) based on RECIST 1.0 criteria. All patients received prophylaxis with the oral phosphate binder sevelamer. Hyperphosphatemia was defined as serum phosphorous >5.5 mg/dL, consistent with the threshold for action in the protocol. Results: Of the 67 patients enrolled, 48 (71.6%) had hyperphosphatemia on ≥1 post-baseline lab test. Efficacy findings in patients with vs without hyperphosphatemia were: ORR 33.3% (95% CI 20.4–48.4) vs 5.3% (95% CI 0.1–26.0), mPFS 4.9 months (95% CI 3.65–5.98) vs 1.84 months (95% CI 1.28–3.48), and mOS 8.74 months (95% CI 5.72–13.67) vs 7.62 months (95% CI 2.53–15.57). Median treatment length was 4.1 vs 1.4 months and mDOR was 5.0 vs 3.7 months for patients with vs without hyperphosphatemia, respectively. A landmark analysis at the 1-month mark was performed, and hyperphosphatemia (Y/N) was determined based on lab tests within the first month. The differences in efficacy outcomes were still observed. Conclusions: Hyperphosphatemia is a well-described class effect and pharmacodynamic biomarker of FGFR inhibitors, including infigratinib, and is generally reversible/easily managed with diet and phosphate binders. Our data support prior observations with FGFR inhibitors, suggesting that hyperphosphatemia is associated with treatment response and is not negatively associated with treatment length. Clinical trial information: NCT01004224.

Safety, dose tolerance, pharmacokinetics, and pharmacodynamics of fosciclopirox (CPX-POM) in patients with advanced solid tumors

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Background: Fosciclopirox (CPX-POM) is being developed for the treatment of non-muscle invasive and muscle invasive bladder cancer. CPX-POM selectively delivers its active metabolite, ciclopirox (CPX), to the entire urinary tract following systemic administration. In a chemical carcinogen mouse model of bladder cancer, CPX-POM treatment resulted in significant decreases in bladder weight, migration to lower stage tumors, inhibition of cell proliferation as well as Notch 1 and Wnt signaling pathways. Methods: Study CPX-POM-001 (NCT03348514) is US multi-site, Phase I, open-label, dose escalation study characterizing the safety, dose tolerance, pharmacokinetics (PK) and pharmacodynamics of IV CPX-POM in advanced solid tumor patients. The PK of CPX-POM, CPX and ciclopirox glucuronide (CPX-G), were characterized in plasma and urine. Circulating biomarkers of Wnt and Notch, IL-6, IL-8 and VEGF were determined. Results: Nineteen patients were enrolled in the study. The starting dose of 30 mg/m2 was administered once daily on Days 1-5 of each 21-day treatment cycle. Doses were escalated to 1200 mg/m2. The MTD was determined to be 900 mg/m2. Overall, the number of treatment-related AE's tended to increase in frequency with dose, nausea and vomiting being the most common. Grade 3 confusion was observed in the 1200 mg/m2 cohort. Four AE's of Grade 1 confusion at 600 and 900 mg/m2. There was no evidence of QTc prolongation or other ECG abnormality. One patient in the 240 mg/m2 dose cohort, with a diagnosis of indolent primary fallopian tube tumor, achieved a partial response per RECIST 1.1. Metabolism of CPX-POM was rapid and complete. The clearance of CPX was dose proportional and time-independent. At MTD, steady-state 24-hour urine CPX concentrations of 215 µM were achieved. Evidence of Notch and Wnt inhibition was observed. Conclusions: IV CPX-POM was well tolerated with treatment-related AEs primarily CNS-related. At MTD, systemic and urinary CPX exposures exceeding in vitro IC50 values by several-fold. The 900 mg/m2 dose is currently being evaluated in an expansion cohort study in cisplatin-ineligible muscle invasive bladder cancer patients scheduled for cystectomy. Clinical trial information: NCT03348514.

Abstract PD5-11: Association of immune gene expression with outcome in the MARIANNE phase 3 clinical trial in HER2-positive metastatic breast cancer (MBC)

Introduction: Although HER2+ breast cancer (BC) is considered a moderately immunogenic tumor, several studies have shown a role of pre-existing immunity associated with favorable long-term prognosis and better response to treatment. In this study, we performed exploratory analyses to assess whether the efficacy of HER2 targeted treatment in the MARIANNE trial correlated with immune gene expression. Methods: MARIANNE (NCT01120184) is a phase 3 study in patients (pts) with centrally confirmed HER2+ local advanced/metastatic BC naïve to prior treatments in the advanced disease. Pts were randomized (1:1:1) to trastuzumab+taxane (HT), T-DM1, or T-DM1+Petuzumab (P) and the trial showed noninferior PFS of T-DM1 and T-DM1+P vs HT. Gene expression (RNA) analysis was performed on tumor samples by a custom 800-gene codeset on the nCounter platform. PD-L1, CD8 expressions and immune gene signatures (sign) analyses were assessed by multivariate Cox regression models using median (cut-off) as categorical variable and adjusted by prior HT, presence of visceral disease, world region, baseline ECOG, measureable disease at baseline, therapy setting, HER2 mRNA expression, PIK3CA mutation status. Results: MARIANNE randomized 1095 pts (HT, n=365; T-DM1, n=367; T-DM1+P, n=363). Gene expression results were available for 671 pts (61.3% of the intent-to-treat [ITT] population) which was representative of ITT. In ITT, HR below 1 was observed when comparing pts with high (>median) vs low (≤median) immune gene expression by clinical outcome suggesting a potential association of high immune marker expression with improved PFS (Table 1) and to some extent with OS (data not shown). This association was primarily observed in the T-DM1 arm where the HR suggested a risk reduction of disease progression(PD)/death especially in the high Teff, high PD-L1 and high CD8 subgroups, and to some extent in the HT arm (Table 1). When assessing the predictive impact on PFS by comparing T-DM1 vs HT, HR below 1 was observed especially in pts with high Teff signature, high PD-L1 and high CD8 expressions (HR 0.67 (95% CI (0.47-0.95)), HR 0.68 (95% CI (0.48-0.97), and HR 0.64 (95%CI 0.44-0.93), respectively). When comparing T-DM1+P vs. HT, HR below 1 was observed especially in pts with low Teff signature and low PD-L1 expression (HR 0.70 (95% CI (0.50-0.99), and HR 0.68 (95% CI (0.48-0.96) respectively). No clear differences between immune gene expression subgroups was observed when comparing treatment arms in regards to OS (data not shown). Conclusions: In the exploratory analysis from the MARIANNE study, high immune gene expression, especially in the high PD-L1, CD8 and Teff subgroups, showed an association with improved clinical benefit with HRs reflecting for a risk reduction of PD/death for PFS and partially for OS. This association was less obvious in the T-DM1+P arm. When comparing the treatments effect, the data showed a potential impact of high Teff signature, and high CD8 and PD-L1 expressions on T-DM1 and less on HT. The potential opposite association of low Teff signature and low PD-L1 expression with improved benefit in the T-DM1+P arm was unexpected and needs further investigation.

Table 1: Prognostic biomarker effect on PFSBiomarker by categories (>Median vs ≤Median)HR (95% CI) ITT n=671HR (95% CI) HT n=220HR (95% CI) T-DM1 n=227HR (95% CI) T-DM1+P n=224Teff sign0.89 (0.73-1.09)0.97 (0.68-1.38)0.64 (0.45-0.91)1.09 (0.75-1.58)Th1 cytokine sign0.91 (0.74-1.11)0.92 (0.64-1.31)0.78 (0.55-1.11)0.96 (0.67-1.36)Checkpoint inhibitor sign0.95 (0.78-1.15)0.91 (0.64-1.29)0.90 (0.64-1.26)1.02 (0.71-1.47)PD-L10.80 (0.66-0.98)0.79 (0.55-1.13)0.62 (0.44-0.87)1.07 (0.74-1.55)CD80.91 (0.75-1.11)1.10 (0.77-1.57)0.66 (0.46-0.93)0.98 (0.68-1.41)

Citation Format: Edith A Perez, Sanne Lysbet de Haas, Carlos H Barrios, Wolfgang Eiermann, Masakazu Toi, Young-Hyuck Im, Pier Franco Conte, Miguel Martin, Tadeusz Pienkowski, Xavier B Pivot, Howard A Burris III, Chiara Lambertini, Silke Hoersch, Monika Patre, Paul Anthony Ellis. Association of immune gene expression with outcome in the MARIANNE phase 3 clinical trial in HER2-positive metastatic breast cancer (MBC) [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 PD5-11.

Association of an RNA signature (RS) with emergence of ICOS hi CD4 T cells and efficacy outcomes for the ICOS agonist vopratelimab (vopra) and nivolumab (nivo) in patients (pts) on the ICONIC trial

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Background: ICOS is a costimulatory molecule upregulated on activated T cells. Vopra is an investigational ICOS agonist antibody that results in activation and proliferation of primed CD4 T effector cells. Vopra was assessed in heavily pretreated patients with advanced solid tumors as monotherapy (mono) or in combination with nivolumab (nivo) in the Phase 1/2 ICONIC trial (NCT02904226). Emergence of a distinct ICOS high (hi) population of peripheral CD4 T effector cells, not seen with PD-1 inhibitors alone, was associated with improved ORR, PFS and OS with vopra mono and combo therapy (AACR 2019). Baseline tumor and blood biomarkers were assessed for ability to predict ICOS hi CD4 T cell emergence and clinical outcomes. Methods: Fresh pre-treatment tumor biopsies were assessed by RS, a gene signature describing immune cell infiltration, and other biomarkers, including PD-L1 TPS by IHC. Pts were classified as RS1 and RS2 based on medium and high cutoffs. Associations between potential predictive biomarkers, ICOS hi CD4 T cell emergence and clinical outcomes were evaluated. Results: Baseline RS is significantly higher in patients with emergence of ICOS hi CD4 T cells. High RS was associated with increased emergence of ICOS hi CD4 T cells, accompanied by improved RECIST response, PFS, and OS. In contrast, no association was noted with PD-L1 IHC. Clinical trial information: NCT02904226. Conclusions: In this retrospective subset analysis, the RS score, but not PD-L1, in baseline tumor biopsies was predictive of emergence of an ICOS hi CD4 T cell population and improved RECIST response, PFS, and OS in patients treated with vopra alone and in combination with nivo. Clinical evaluation of vopra and investigational PD-1 inhibitor JTX-4014 in cancer patients with RS selection is planned. [Table: see text]

Abstract PR03: A phase 1 trial of AG-270 in patients with advanced solid tumors or lymphoma with homozygous MTAP deletion

Background: Homozygous deletion of MTAP, the gene encoding the metabolic enzyme methylthioadenosine phosphorylase, occurs in ~15% of human malignancies. Tumor cells with this deletion are selectively vulnerable to decreases in the methyl donor S-adenosylmethionine (SAM). AG-270 is a first-in-class, oral, potent, reversible inhibitor of methionine adenosyltransferase 2A (MAT2A), the key enzyme responsible for SAM synthesis. We report preliminary results from an ongoing, first-in-human, phase 1 trial of AG-270 (ClinicalTrials.gov Identifier: NCT03435250). Aims: The primary objective of this study is to determine the maximum tolerated dose (MTD) of AG-270. Secondary objectives include safety, tolerability, pharmacokinetics (PK), pharmacodynamics (PD), and efficacy. Methods: Eligibility requires homozygous deletion of cyclin dependent kinase inhibitor 2A (CDKN2A) in the patient’s tumor (as MTAP is usually co-deleted with CDKN2A), or loss of MTAP by IHC. Patients receive AG-270 daily in 28-day cycles, with intensive PK/PD sampling after the first dose and after 2 weeks of treatment. Paired tumor biopsies are collected at baseline and at the end of cycle 1. Disease evaluation is performed every 2 cycles. Results: As of 20 May 2019, 39 patients had been treated with AG-270: 50 mg once daily (QD; n=3), 100 mg QD (n=7), 150 mg QD (n=6), 200 mg QD (n=11), 400 mg QD (n=6), or 200 mg twice daily (BID; n=6). AG-270 was well absorbed. Plasma concentrations increased in a dose-proportional manner except at 400 mg QD, where exposure was lower than anticipated. The geometric mean area under the curve from 0-24 h at steady state (AUC0-24,ss) in the QD cohorts ranged from 33200 to 199085 ng*h/mL, and the geometric mean AUC0-24,ss in the 200 mg BID cohort was 254616 ng*h/mL. The median half-life of AG-270 ranged from 16.1 to 38.4 h. Decreases in plasma [SAM] were exposure-dependent. After 2 weeks of dosing, maximal reductions in plasma [SAM] ranged from 51% to 71% across the tested cohorts. Analysis of 9 paired tumor biopsies by IHC showed decreases in levels of symmetrically di-methylated arginine (SDMA) residues, consistent with MAT2A inhibition; the average H-score reduction compared to baseline was 36.4% [-98.8%, +21.4%]. Asymptomatic, exposure-dependent increases in unconjugated bilirubin were observed starting at 100 mg QD, consistent with the known potential of AG-270 to inhibit UGT1A1. Three patients (at 100 mg QD, 150 mg QD, and 200 mg BID) developed grade 2 and 3 diffuse erythematous rashes during the second week of dosing that resolved within 1 week of stopping treatment. Exposure-dependent, reversible decreases in platelet counts were first observed at 200 mg QD and were grade 3 and 4 in severity at 200 mg BID. Two patients treated at 200 mg BID developed reversible but dose-limiting grade 3 and 4 increases in liver enzymes. The MTD of AG-270 is 200 mg QD. An unconfirmed partial response has been observed in a patient with a high-grade neuroendocrine carcinoma of the lung. Seven patients have achieved radiographically confirmed stable disease of 2.0 to 9.9 months’ duration. Conclusions: AG-270 causes reductions in plasma [SAM] and in tumor SDMA levels at well-tolerated doses. This trial will next evaluate the combination of AG-270 with taxane-based chemotherapy, given preclinical data demonstrating enhanced antitumor activity with AG-270 and taxanes in MTAP-deleted cancer models.

Citation Format: Rebecca S Heist, Mrinal M Gounder, Sophie Postel-Vinay, Frederick Wilson, Elena Garralda, Khanh Do, Geoffrey I Shapiro, Patricia Martin-Romano, Gerburg Wulf, Michael Cooper, Caroline Almon, Salah Nabhan, Varsha Iyer, Yanwei Zhang, Kevin Marks, Elia Aguado-Fraile, Frank Basile, Keith Flaherty, Howard A Burris. A phase 1 trial of AG-270 in patients with advanced solid tumors or lymphoma with homozygous MTAP deletion [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr PR03. doi:10.1158/1535-7163.TARG-19-PR03

Patient Navigation in Cancer: The Business Case to Support Clinical Needs

PURPOSE

Patient navigation (PN) is an increasingly recognized element of high-quality, patient-centered cancer care, yet PN in many cancer programs is absent or limited, often because of concerns of extra cost without tangible financial benefits.

METHODS

Five real-world examples of PN programs are used to demonstrate that in the pure fee-for-service and the alternative payment model worlds of reimbursement, strong cases can be made to support the benefits of PN.

RESULTS

In three large programs, PN resulted in increased patient retention and increased physician loyalty within the cancer programs, leading to increased revenue. In addition, in two programs, PN was associated with a reduction in unnecessary resource utilization, such as emergency department visits and hospitalizations. PN also reduces burdens on oncology providers, potentially reducing burnout, errors, and costly staff turnover.

CONCLUSION

PN has resulted in improved patient outcomes and patient satisfaction and has important financial benefits for cancer programs in the fee-for-service and the alternative payment model worlds, lending support for more robust staffing of PN programs.

Atezolizumab (MPDL3280A) Monotherapy for Patients With Metastatic Urothelial Cancer: Long-term Outcomes From a Phase 1 Study

Importance

Atezolizumab (anti-programmed death ligand 1) has demonstrated safety and activity in advanced and metastatic urothelial carcinoma, but its long-term clinical profile remains unknown.

Objective

To report long-term clinical outcomes with atezolizumab therapy for patients with metastatic urothelial carcinoma.

Design, Setting, and Participants

Patients were enrolled in an expansion cohort of an ongoing, open-label, phase 1 study. Median follow-up was 37.8 months (range, >0.7 to 44.4 months). Enrollment occurred between March 2013 and August 2015 at US and European academic medical centers. Eligible patients had measurable disease per Response Evaluation Criteria in Solid Tumors version 1.1, Eastern Cooperative Oncology Group performance status 0 to 1, and a representative tumor sample. Programmed death ligand 1 expression on immune cells was assessed (VENTANA SP142 assay).

Interventions

Atezolizumab was given intravenously every 3 weeks until unacceptable toxic effects, protocol nonadherence, or loss of clinical benefit.

Main Outcomes and Measures

Primary outcome was safety. Secondary outcomes included objective response rate, duration of response, and progression-free survival. Response and overall survival were assessed in key baseline subgroups.

Results

Ninety-five patients were evaluable (72 [76%] male; median age, 66 years [range, 36-89 years]). Forty-five (47%) received atezolizumab as third-line therapy or greater. Nine patients (9%) had a grade 3 to 4 treatment-related adverse event, mostly within the first treatment year; no serious related adverse events were observed thereafter. One patient (1%) discontinued treatment due to a related event. No treatment-related deaths occurred. Responses occurred in 26% (95% CI, 18%-36%) of patients. Median duration of response was 22.1 months (range, 2.8 to >41.0 months), and median progression-free survival was 2.7 months (95% CI, 1.4-4.3 months). Median overall survival was 10.1 months (95% CI, 7.3-17.0 months); 3-year OS rate was 27% (95% CI, 17%-36%). Response occurred in 40% (95% CI, 26%-55%; n = 40) and 11% (95% CI, 4%-25%; n = 44) of patients with programmed death ligand 1 expression of at least 5% tumor-infiltrating immune cells (IC2/3) or less than 5% (IC0/1), respectively. Median overall survival in patients with IC2/3 and IC0/1 was 14.6 months (95% CI, 9.0 months to not estimable) and 7.6 months (95% CI, 4.7 to 13.9 months), respectively.

Conclusions and Relevance

Atezolizumab remained well tolerated and provided durable clinical benefit to a heavily pretreated metastatic urothelial carcinoma population in this long-term study.

Trial Registration

clinicaltrials.gov Identifier: NCT01375842.

A Randomized, Double-Blinded, Phase II Trial of Carboplatin and Pemetrexed with or without Apatorsen (OGX-427) in Patients with Previously Untreated Stage IV Non-Squamous-Non-Small-Cell Lung Cancer: The SPRUCE Trial

BACKGROUND

This randomized, double-blinded, phase II trial evaluated the efficacy of carboplatin and pemetrexed plus either apatorsen, an antisense oligonucleotide targeting heat shock protein (Hsp) 27 mRNA, or placebo in patients with previously untreated metastatic nonsquamous non-small cell lung cancer (NSCLC).

METHODS

Patients were randomized 1:1 to Arm A (carboplatin/pemetrexed plus apatorsen) or Arm B (carboplatin/pemetrexed plus placebo). Treatment was administered in 21-day cycles, with restaging every two cycles, until progression or intolerable toxicity. Serum Hsp27 levels were analyzed at baseline and during treatment. The primary endpoint was progression-free survival (PFS); secondary endpoints included overall survival (OS), objective response rate, and toxicity.

RESULTS

The trial enrolled 155 patients (median age 66 years; 44% Eastern Cooperative Oncology Group performance status 0). Toxicities were similar in the 2 treatment arms; cytopenias, nausea, vomiting, and fatigue were the most frequent treatment-related adverse events. Median PFS and OS were 6.0 and 10.8 months, respectively, for Arm A, and 4.9 and 11.8 months for Arm B (differences not statistically significant). Overall response rates were 27% for Arm A and 32% for Arm B. Sixteen patients (12%) had high serum levels of Hsp27 at baseline. In this small group, patients who received apatorsen had median PFS of 10.8 months, and those who received placebo had median PFS 4.8 months.

CONCLUSION

The addition of apatorsen to carboplatin and pemetrexed was well tolerated but did not improve outcomes in patients with metastatic nonsquamous NSCLC cancer in the first-line setting.

IMPLICATIONS FOR PRACTICE

This randomized, double-blinded, phase II trial evaluated the efficacy of carboplatin and pemetrexed plus either apatorsen, an antisense oligonucleotide targeting heat shock protein 27 mRNA, or placebo in patients with previously untreated metastatic nonsquamous non-small cell lung cancer (NSCLC). The addition of apatorsen to carboplatin and pemetrexed was well tolerated but did not improve outcomes in patients with metastatic nonsquamous NSCLC cancer in the first-line setting.

WITHDRAWN: Cardio-Oncology: Stronger Together

This article has been removed from JACC where it was posted in error. It is an article for JACC: CardioOncology (10.1016/j.jaccao.2019.08.001) and will be included in the first issue. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Abstract CT189: Improved progression-free and overall survival (PFS/OS) in patients (pts) with emergence of JTX-2011 associated biomarker (ICOS high CD4 T cells) on the ICONIC trial

Background: ICOS is a costimulatory molecule upregulated on activated T cells. JTX-2011 is an ICOS agonist antibody intended to stimulate primed CD4 T effector cells. JTX-2011 was assessed in pts with advanced solid tumors as monotherapy (mono) and combination (combo) with nivolumab (nivo) in the Phase I/II ICONIC trial (NCT02904226). Peripheral T cell phenotyping in ICONIC demonstrated emergence of an ICOS high (hi) subset of CD4 T cells associated with tumor reductions in mono and combo pts. In ex vivo studies, soluble JTX-2011 stimulated a polyfunctional cytokine response only in ICOS hi cells.

Methods: Ad hoc flow cytometry phenotyping on PBMCs from a subset of pts with evaluable samples (n=50) was initiated retrospectively in early 2018 in ongoing pts, then prospectively on newly enrolled pts. Clinical characteristics and outcomes were analyzed, including unadjusted p-values for post-hoc statistical analyses. Phenotyping was also done on samples from pts treated with PD-1/L1 inhibitor (PD-1/L1i) mono collected outside of ICONIC.

Results: Emergence of ICOS hi CD4 T effector cells (all FoxP3-, subset Tbet+ Ki67+) was observed in all pts with ≥30% target lesion tumor reduction by investigator assessment on mono and combo therapy (n=7). Emergence was seen in pts with stable target lesions (n=11/23) including loss of these cells with disease progression. ICOS hi cells were not seen in ICONIC pts with target lesion increase ≥20% (n=14), or in pts treated with PD-1/L1i mono, including responders. Emergence of ICOS hi CD4 T cells correlated with improved PFS and OS (Table).

ICONIC Pt characteristicsICOS hi (N=18)ICOS low (N=32)≥3 prior therapies, n (%)13 (72.2)18 (56.3)Prior immunotherapy, n (%)6 (33.3)15 (46.9)Tumor type, n (%)Gastric n=9 (50), NSCLC n=3 (16.7), TNBC n=2 (11.1), Other n=4 (22.2)Gastric n=8 (25), NSCLC n=6 (18.8), TNBC n=4 (12.5), Other n=14 (43.8),Mono vs Combo, n (%)Mono n=2 (11.1), Combo n=16 (88.9)Mono n=11 (34.4), Combo n=21 (65.6)G3-4 treatment-related adverse events, n (%)1 (5.6)2 (6.3)Time on JTX-2011, median mths (range), p=0.00065.6 (1.45-18.4)1.41 (0.03-6.28)PFS, investigator and central imaging review, median mths, (investigator, p<0.0001; central p=0.0011)6.22OS, median mths, p=0.0183(not yet reached)9

Conclusion: Emergence of a distinct ICOS hi population of peripheral CD4 T cells is associated with improved PFS and OS with JTX-2011 mono and combo therapy. Two JTX-2011 development paths are planned: (1) combo with agents that induce ICOS hi CD4 T cells; (2) use of potential putative biomarkers predictive of emergence of this T cell population and JTX-2011 response.

Citation Format: Timothy Anthony Yap, Justin F. Gainor, Margaret K. Callahan, Gerald S. Falchook, Russell Kent Pachynski, Patricia LoRusso, Shivaani Kummar, Geoffrey Thomas Gibney, Howard A. Burris, Scott S. Tykodi, Osama E. Rahma, Tanguy Seiwert, Kyriakos P. Papadopoulos, Ellen Hooper, Christopher J. Harvey, Amanda Hanson, Sean Lacey, Rachel McComb, Courtney Hart, Haley Laken, Ty McClure, Elizabeth Trehu. Improved progression-free and overall survival (PFS/OS) in patients (pts) with emergence of JTX-2011 associated biomarker (ICOS high CD4 T cells) on the ICONIC trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr CT189.