Weiss, Glen J.

Aberrant activation of the Hippo–YAP/TAZ–TEAD transcriptional axis is a recurrent feature of multiple solid tumors and contributes to tumor maintenance, lineage plasticity, and therapeutic resistance. Recent medicinal chemistry has shown that TEAD proteins are druggable, but the rate at which in silico screening nominates compounds that prove functionally active in cells remains poorly defined, and negative validation results are rarely reported. Here we describe an experimental assessment of a focused set of computationally nominated candidate compounds, selected from a structure-guided virtual screen of the YAP–TEAD interface across approximately 917,000 library compounds and three predicted binding sites. Candidates were evaluated using long-term (144 hour) CellTiter-Glo proliferation assays in three Hippo-altered malignant pleural mesothelioma cell lines (MSTO-211H, NCI-H2052, NCI-H226), with the validated TEAD inhibitor K-975 and cisplatin as positive controls, and an exploratory TEAD-responsive luciferase reporter in MCF7 cells. K-975 produced dose-dependent antiproliferative activity in MSTO-211H and NCI-H2052, with reduced sensitivity in NCI-H226, while cisplatin reduced viability in all lines. In contrast, the computationally nominated compounds, including AG-690/36549045, AN-655/40856217, and additional library members, did not produce measurable antiproliferative activity at the concentrations tested. In the exploratory reporter, apparent suppression of TEAD activity consistently co-occurred with loss of cell viability, a pattern consistent with cytotoxicity rather than selective transcriptional inhibition; no TEAD-active reference compound was co-tested within the reporter panel, and no direct YAP–TEAD biochemical or target-engagement assay was performed. These results describe a case in which computational nomination at the YAP–TEAD interface showed limited concordance with cell-based activity and provide a transparent account of negative findings to inform expectations for early-stage discovery targeting Hippo-dependent transcriptional programs.

Background/Objectives: KRAS G12C mutations define a clinically actionable subset of solid tumors, particularly non–small cell lung cancer. Clinical responses to approved covalent inhibitors remain limited by intrinsic and acquired resistance, highlighting the need for structurally distinct inhibitor scaffolds to expand therapeutic options. The objective of this study was to identify novel covalent binders targeting the KRAS G12C switch-II pocket through large-scale in silico screening and experimental validation. Methods: More than 1.9 million small molecules from diverse commercial libraries were screened using covalent docking, followed by multi-stage refinement incorporating molecular dynamics simulations, MM/GBSA free-energy estimation, and cancer-focused QSAR modeling. Results: This integrated workflow yielded 50 prioritized compounds spanning several chemically distinct scaffold classes. These candidates displayed favorable predicted binding energetics, stable ligand-protein interactions over extended simulation timescales, and low structural similarity to clinically approved KRAS G12C inhibitors sotorasib and adagrasib. Benchmarking against these clinical agents, using identical computational parameters, yielded comparable predicted binding energies for several candidate molecules. In cellular NanoBRET target-engagement assays, selected scaffolds, including K788-7251 and AN-989/14669131, exhibited sub-micromolar engagement of KRAS G12C with minimal endothelial cytotoxicity. Conclusions: Collectively, these findings identify structurally distinct, KRAS G12C inhibitor chemotypes and provide tractable starting points for the development of next-generation targeted therapies.

Broad-spectrum therapeutics in non-small cell lung cancer (NSCLC) are in demand. Most human solid tumors express proteoglycans modified with distinct oncofetal chondroitin sulfate (CS) chains that can be detected and targeted with recombinant VAR2CSA (rVAR2) proteins and rVAR2-derived therapeutics. Here, we investigated expression and targetability of oncofetal CS expression in human NSCLC. High oncofetal CS expression is associated with shorter disease-free survival and poor overall survival of clinically annotated stage I and II NSCLC patients (n = 493). Oncofetal CS qualifies as an independent prognosticator of NSCLC in males and smokers, and high oncofetal CS levels are more prevalent in EGFR/KRAS wild-type cases, as compared to mutation cases. NSCLC cell lines express oncofetal CS-modified proteoglycans that can be specifically detected and targeted by rVAR2 proteins in a CSA-dependent manner. Importantly, a novel VAR2-drug conjugate (VDC-MMAE) efficiently eliminates NSCLC cells in vitro and in vivo. In summary, oncofetal CS is a prognostic biomarker and an actionable glycosaminoglycan target in NSCLC.

3060 Background: EP-100 is a synthetic 28 amino acid LHRH peptide conjugated to an 18 aa cytolytic peptide. Selective targeting in LHRH-R expressing cells occurs via direct binding to the extracellular membrane receptor followed by disruption of the membrane by the cytolytic peptide portion. A first in human, phase I study was performed. Methods: Eligible pts had adequate organ function and LHRH-R tumor expression, as determined by IHC. EP-100 was given IV (30-60 min) weekly x 3 for cohorts 1- 6 (n=20 at 0.6 - 5.2 mg/m2) and then twice weekly x 3 for cohorts 7- 11 (n=18 at 7.8 - 40 mg/m2) with a week break. The pharmacokinetic profile of EP-100 and antibody production against EP-100 was determined by a validated HPLC/MS and ELISA respectively. Potential activity of EP-100 on the pituitary gonadotropes was determined by plasma LH and FSH. Results: We screened 97 pts, archival tumor tissue obtained from 81 pts; 53 (65%) were positive for LHRH-R, of which 37 were enrolled (female 76%) and treated. The LHRH-R expression rate in breast was 81% (N=21) and in ovarian cancer 56% (n=18). Most pts had breast (n= 16, 42%) ovary (n=7,18%), colon (n=4, 11%) or uterine (n=3, 8%) cancer. Pts were treated in a 3 + 3 standard dose escalation scheme. Doses were escalated 100% in the absence of a grade 2 drug related toxicity. MTD was not reached at the highest dose level of 40 mg/m2. Only one DLT occurred, a grade 2 increase in ALT/AST. The only other drug-related toxicity was a self limited infusion-related skin reaction (grade 1-2) in 10 pts. EP-100 was rapidly cleared from circulation, mean half life ranged from 7.1 ± 3.8 min to 15.9 ± 3.6 min. Best response was stable disease for >12 weeks in 5 pts. In 3 pts rapid, sustained decreases in LH/FSH levels were noted. Antibody production against EP-100 was absent in all pts. Conclusions: The study has completed accrual, the phase II dose is 30-40 mg/m2 twice a week x 3 weeks.EP-100is safe, well tolerated and not antigenic/immunogenic. Preclinical studies indicated synergy with paclitaxel and doxorubicin. A phase II study of EP-100 plus paclitaxel in ovarian cancer is planned.

359 Background: GA, FOLFIRINOX and FOLFIRI are standard chemotherapy (CTX) regimens for mPC.The optimal introduction of these regimens following GA is not known. This phase II study evaluated 2 different approaches to this question. Methods: Eligibility criteria included 1) untreated mPC, 2) ECOG PS 0/1, 3) organ function adequate for Rx. Patients (pts) were treated according to one of 2 methods following GA given per standard dose/schedule: FOLFIRINOX (bolus 5-FU omitted) for up to 12 cycles at 24 weeks or at time of disease progression (S); or GA alternating with FOLFIRI q8 weeks up to 48 weeks total Rx (A). Results: 54 evaluable pts (28S, 26A) were enrolled . Pt characteristics included median age 65, M/F 48/52% , liver involvement 89%. 17/53 pts (31%) did not achieve disease control at 8 weeks (8 toxicity/complications , 6 disease progression, 3 declined further protocol therapy). Of the remaining 37 pts, 24/13 were treated with S/A regimens, respectively. Grade ≥ 3 treatment toxicities reported while on study with frequency ≥ 10% included anemia 21%, neutropenia 43%, thrombocytopenia 15%, and fatigue 22%. Grade ≥ 3 neuropathy occurred in 8% of pts. For all 54 pts using RECIST 1.0, CR/PR/SD/DC was 2 (4%)/20 (37%)/19 (35%)/41(76%). Ca19.9 response ≥ 90% was seen in 20/37 (54%). For all pts, median OS was 12.3 months ( 95% CI 8.6-14.5 mo); 12 and 24 mo OS was 51% and 11%, respectively. For the 37 pts with DC on GA at 8 weeks (calculated from start Rx) median OS was 13.5 mo (95% CI 10.7-15.4 mo); 12 and 24 mo OS was 55% and 16% , respectively. No statistically significant differences were seen between S and A with respect to toxicity, response or survival. Conclusions: 1) As opposed to introduction of 5FU-based CTX at the time of disease progression/prohibitive toxicity, introduction prior to that time may be at least comparable regarding both toxicity and OS. 2) This approach may further enhance OS in pts who achieve DC on GA at 8 weeks. 3) Neither S nor A method of 5FU-based CTX introduction following GA was clearly superior in this study. 4) How best to combine 5FU-based combination CTX following GA in mPC merits further study. Supported by the Seena Magowitz Foundation.

Abstract Purpose: First-in-human phase I trial to determine the safety, pharmacokinetics, and antitumor activity of BIND-014, a novel, tumor prostate-specific membrane antigen (PSMA)–targeted nanoparticle, containing docetaxel. Experimental Design: Patients with advanced solid tumors received BIND-014 every three weeks (n = 28) or weekly (n = 27), with dose levels ranging from 3.5 to 75 mg/m2 and 15 to 45 mg/m2, respectively. Results: BIND-014 was generally well tolerated, with no unexpected toxicities. The most common drug-related toxicities (>20% of patients) on either schedule included neutropenia, fatigue, anemia, alopecia, and diarrhea. BIND-014 demonstrated a dose-linear pharmacokinetic profile, distinct from docetaxel, with prolonged persistence of docetaxel-encapsulated circulating nanoparticles. Of the 52 patients evaluable for response, one had a complete response (cervical cancer on the every three week schedule) and five had partial responses (ampullary adenocarcinoma, non–small cell lung, and prostate cancers on the every-three-week schedule, and breast and gastroesophageal cancers on the weekly schedule). Responses were noted in both PSMA-detectable and -undetectable tumors. Conclusions: BIND-014 was generally well tolerated, with predictable and manageable toxicity and a unique pharmacokinetic profile compared with conventional docetaxel. Clinical activity was noted in multiple tumor types. The recommended phase II dose of BIND-014 is 60 mg/m2 every three weeks or 40 mg/m2 weekly. Clin Cancer Res; 22(13); 3157–63. ©2016 AACR.

Abstract Purpose: This study was designed to establish the maximum tolerated dose (MTD) and to evaluate tolerability, pharmacokinetics, and antitumor activity of etirinotecan pegol. Experimental Design: Patients with refractory solid malignancies were enrolled and assigned to escalating-dose cohorts. Patients received 1 infusion of etirinotecan pegol weekly 3 times every 4 weeks (w × 3q4w), or every 14 days (q14d), or every 21 days (q21d), with MTD as the primary end point using a standard 3 + 3 design. Results: Seventy-six patients were entered onto 3 dosing schedules (58–245 mg/m2). The MTD was 115 mg/m2 for the w × 3q4w schedule and 145 mg/m2 for both the q14d and q21d schedules. Most adverse events related to study drug were gastrointestinal disorders and were more frequent at higher doses of etirinotecan pegol. Late onset diarrhea was observed in some patients, the frequency of which generally correlated with dose density. Cholinergic diarrhea commonly seen with irinotecan treatment did not occur in patients treated with etirinotecan pegol. Etirinotecan pegol administration resulted in sustained and controlled systemic exposure to SN-38, which had a mean half-life of approximately 50 days. Overall, the pharmacokinetics of etirinotecan pegol are predictable and do not require complex dosing adjustments. Confirmed partial responses were observed in 8 patients with breast, colon, lung (small and squamous cell), bladder, cervical, and neuroendocrine cancer. Conclusion: Etirinotecan pegol showed substantial antitumor activity in patients with various solid tumors and a somewhat different safety profile compared with the irinotecan historical profile. The MTD recommended for phase II clinical trials is 145 mg/m2 q14d or q21d. Clin Cancer Res; 19(1); 268–78. ©2012 AACR.

AbstractThe use of 18‐fluorodeoxyglucose (FDG) positron emission tomography with computed tomography (PET/CT) in subjects with advanced basal cell carcinoma (BCC) has not been fully explored due to the rarity of disease presentation. This study evaluated PET/CTs from subjects with advanced BCC participating in a phase I dose‐escalation clinical trial of vismodegib. Fourteen subjects with BCC were imaged with 18‐FDG PET/CT for lesion identification and response categorizing (European Organisation for Research and Treatment for Cancer [EORTC] and PET response criteria in solid tumors [PERCIST] 1.0). Several parameters including metabolic activity of target lesions, site of disease presentation and spread, treatment response, and prognostic significance of metabolic activity following therapy were evaluated. All subjects exhibited at least one hypermetabolic lesion. Most subjects had only four organ systems involved at study enrollment: skin–muscle (93%), lung (57%), lymph nodes (29%), and bone (21%). SUVmax measured across all lesions decreased (median 33%, SD ± 45%) following therapy with metabolic activity normalizing or disappearing in 42% of lesions. No significant difference was observed between EORTC and PERCIST 1.0. Subjects that demonstrated at least a 33% reduction in SUVmax from baseline had a significantly longer progression‐free survival (PFS) (median 17 months, 95% confidence interval [CI] ±4 months vs. 9 months, 95% CI ±5 months, P = 0.038) and overall survival (OS) (median 24 months, 95% CI ±4 months vs. 17 months, 95% CI ±13 months, P = 0.019). BCC lesions are hypermetabolic on 18‐FDG PET/CT. A decrease in SUVmax was associated with improved PFS and OS. These results further support the incorporation of 18‐FDG PET/CT scans in advanced BCC management.

Abstract Purpose: Pancreatic adenocarcinoma is among the most lethal forms of all malignancies. While significant research has implicated multiple genes in disease pathogenesis, identification of therapeutic leads has been difficult. The majority of currently available therapies provide only marginal benefit. To address this issue, our goal was to assess global somatic events across multiple pancreatic tumors by using next-generation sequencing technologies (NGS). Experimental Design: We performed whole genome sequencing (WGS) on paired tumor and normal samples from 3 pancreatic adenocarcinoma patients. Additionally, we performed whole transcriptome sequencing (WTS) on 2 of these patients’ tumors for which tumor RNA was available. Results: We generated on average 132 billion mappable bases across all patients using WGS, and identified 140 somatic coding events including point mutations, insertion/deletions, and chromosomal copy number variants. Data from WGS and WTS were integrated and analyzed to identify the most heavily affected pancreatic cancer pathways across all patients. The KRAS signaling pathway was identified as the most significant map. Unbiased global pathway analysis was also performed to identify processes that may be impacted. Consistent with the previous analysis, the most significant pathway from this analysis is also KRAS signaling. This integrated analysis specifically identifies heavily affected pathways in pancreatic cancer and pinpoints genes and processes that may be considered as targets for more effective therapies. Conclusions: While sequencing of additional patients is necessary to strengthen selection of key pathways, we demonstrate the utility of using NGS to understand the processes driving pancreatic adenocarcinoma so that standardized treatments for patients may be improved. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5104. doi:1538-7445.AM2012-5104

Abstract Purpose: The objectives of this phase 1, first-in-human study were to determine the dose-limiting toxicities (DLT), maximum tolerated dose (MTD), safety, pharmacokinetics, and preliminary activity of the hypoxia-activated prodrug TH-302 in patients with advanced solid tumors. Experimental Design: TH-302 was administered intravenously over 30 to 60 minutes in two regimens: three times weekly dosing followed by 1 week off (arm A) and every 3-week dosing (arm B). Results: Fifty-seven patients enrolled (arm A: N = 37 and arm B: N = 20). The TH-302 dose was escalated from 7.5 to 670 mg/m2 in arm A and from 670 to 940 mg/m2 in arm B. The most common adverse events were nausea, skin rash, fatigue, and vomiting. Hematologic toxicity was mild and limited. Grade 3 skin and mucosal toxicities were dose limiting at 670 mg/m2 in arm A; the MTD was 575 mg/m2. In arm B, grade 3 fatigue and grade 3 vaginitis/proctitis were dose limiting at 940 mg/m2; the MTD was 670 mg/m2. Plasma concentrations of TH-302 and the active metabolite Br-IPM (brominated version of isophosphoramide mustard) increased proportionally with dose. Two partial responses were noted in patients with metastatic small cell lung cancer (SCLC) and melanoma in arm A at 480 and 670 mg/m2. Stable disease was observed in arms A and B in 18 and 9 patients, respectively. Conclusions: The MTD of TH-302 was 575 mg/m2 weekly and 670 mg/m2 every 3 weeks. Skin and mucosal toxicities were DLTs. On the basis of responses in metastatic melanoma and SCLC, further investigations in these indications were initiated. Clin Cancer Res; 17(9); 2997–3004. ©2011 AACR.