Citations

Abstract Cerebral white matter rarefaction (CWMR) was considered by Binswanger and Alzheimer to be due to cerebral arteriolosclerosis. Renewed attention came with CT and MR brain imaging, and neuropathological studies finding a high rate of CWMR in Alzheimer disease (AD). The relative contributions of cerebrovascular disease and AD to CWMR are still uncertain. In 1181 autopsies by the Arizona Study of Aging and Neurodegenerative Disorders (AZSAND), large-format brain sections were used to grade CWMR and determine its vascular and neurodegenerative correlates. Almost all neurodegenerative diseases had more severe CWMR than the normal control group. Multivariable logistic regression models indicated that Braak neurofibrillary stage was the strongest predictor of CWMR, with additional independently significant predictors including age, cortical and diencephalic lacunar and microinfarcts, body mass index, and female sex. It appears that while AD and cerebrovascular pathology may be additive in causing CWMR, both may be solely capable of this. The typical periventricular pattern suggests that CWMR is primarily a distal axonopathy caused by dysfunction of the cell bodies of long-association corticocortical projection neurons. A consequence of these findings is that CWMR should not be viewed simply as “small vessel disease” or as a pathognomonic indicator of vascular cognitive impairment or vascular dementia.

Abstract Background and study aims Significant weight regain affects up to one-third of patients after Roux-en-Y gastric bypass (RYGB) and demands treatment. Transoral outlet reduction (TORe) with argon plasma coagulation (APC) alone or APC plus full-thickness suturing TORe (APC-FTS) is effective in the short term. However, no study has investigated the course of gastrojejunostomy (GJ) or quality of life (QOL) data after the first post-procedure year. Patients and methods Patients eligible for a 36-month follow-up visit after TORe underwent upper gastrointestinal endoscopy with measurement of the GJ and answered QOL questionnaires (RAND-36). The primary aim was to evaluate the long-term outcomes of TORe, including weight loss, QOL, and GJ anastomosis (GJA) size. Comparisons between APC and APC-FTS TORe were a secondary aim. Results Among 39 eligible patients, 29 returned for the 3-year follow-up visit. There were no significant differences in demographics between APC and APC-FTS TORe groups. At 3 years, patients from both groups regained all the weight lost at 12 months, and the GJ diameter was similar to the pre-procedure assessment. As to QOL, most improvements seen at 12 months were lost at 3 years, returning to pre-procedure levels. Only the energy/fatigue domain improvement was kept between the 1- and 3-year visits. Conclusions Obesity is a chronic relapsing disease. Most effects of TORe are lost at 3 years, and redilation of the GJA occurs. Therefore, TORe should be considered iterative rather than a one-off procedure.

OBJECTIVE The purpose of this study was to analyze risk factors for sacral fracture following noninstrumented partial sacral amputation for en bloc chordoma resection. METHODS A multicenter retrospective chart review identified patients who underwent noninstrumented partial sacral amputation for en bloc chordoma resection with pre- and postoperative imaging. Hounsfield units (HU) were measured in the S1 level. Sacral amputation level nomenclature was based on the highest sacral level with bone removed (e.g., S1 foramen amputation at the S1–2 vestigial disc is an S2 sacral amputation). Variables collected included basic demographics, patient comorbidities, surgical approach, preoperative radiographic details, neoadjuvant and adjuvant radiation therapy, and postoperative sacral fracture data. RESULTS A total of 101 patients (60 men, 41 women) were included; they had an average age of 69 years, BMI of 29 kg/m2, and follow-up of 60 months. The sacral amputation level was S1 (2%), S2 (37%), S3 (44%), S4 (9%), and S5 (9%). Patients had a posterior-only approach (77%) or a combined anterior–posterior approach (23%), with 10 patients (10%) having partial sacroiliac (SI) joint resection. Twenty-seven patients (27%) suffered a postoperative sacral fracture, all occurring between 1 and 7 months after the index surgery. Multivariable logistic regression analysis demonstrated S1 or S2 sacral amputation level (p = 0.001), combined anterior–posterior approach (p = 0.0064), and low superior S1 HU (p = 0.027) to be independent predictors of sacral fracture. The fracture rate for patients with superior S1 HU < 225, 225–300, and > 300 was 38%, 15%, and 9%, respectively. An optimal superior S1 HU cutoff of 300 was found to maximize sensitivity (89%) and specificity (42%) in predicting postamputation sacral fracture. In addition, the fracture rate for patients who underwent partial SI joint resection was 100%. CONCLUSIONS Patients with S1 or S2 partial sacral amputations, a combined anterior–posterior surgical approach, low superior S1 HU, and partial SI joint resection are at higher risk for postoperative sacral fracture following en bloc chordoma resection and should be considered for spinopelvic instrumentation at the index procedure.

Abstract Background: ELU001 is a novel, first-in-class, new molecular entity described as a C’Dot Drug Conjugate (CDC). ELU001 consists of ~13 folic acid targeting moieties and a payload of ~22 molecules of the topoisomerase-1 inhibitor, exatecan. Folic acid and exatecan are covalently bound by non-cleavable and cathepsin-B cleavable linkers, respectively, to short polyethylene glycol chains which surround the C’Dot’s silica core. CDCs are very small (~6 nm), allowing greater ability to penetrate more efficiently into solid tumors compared to ADCs. CDCs are rapidly eliminated by the kidneys, which is expected to lead to less toxicity than ADCs that have a longer half-life in circulation. ELU001’s high avidity is designed to promote binding to FRα on the surface on FRα overexpressing cancer cells with a wide range of antigen expression including high, moderate and low expressing tumor cells. Following antigen binding, ELU001 internalizes into the tumor cell, and traffics to the lysosome where enzymatic cleavage releases the exatecan payload. The first-in-human trial, ELU-FRα-1, is currently recruiting patients that have advanced, recurrent or refractory tumors associated with indications that are known to potentially overexpress FRα and have been shown to be topoisomerase 1 inhibitor-sensitive, and, in the opinion of the Investigator, have no satisfactory therapeutic options available. Methods: This is a Phase 1/2 multicenter, open label clinical trial with two parts: Part 1 Dose Escalation and Part 2 Tumor Group Expansion Cohort(s). Part 1 is a basket trial enrolling patients with cancer types with a high likelihood of having FRα overexpressing tumors, (specifically, ovarian, endometrial, colorectal, gastric, gastroesophageal junction, triple negative breast, or non-small cell lung cancers, or cholangiocarcinoma). Patients are receiving ELU001 weekly (QW) (once a week for 3 weeks, 1 week rest), every other week (Q2W, with no rest between cycles), or every three weeks (Q3W). Analysis of FRα expression will be retrospectively determined. Part 2 will use Simon’s Two-Stage design to evaluate 4-6 Expansion Cohorts, comprised of tumor histologies anticipated to have greatest activity to ELU001 treatment. FRα will be prospectively determined. The primary objective for Part 1 is to identify the MTD/RP2D. The primary objective for Part 2 is to determine the ORR. Secondary objectives include DOR, PFS, TFST, PFS2, OS, frequency, severity and tolerability of adverse events, PK, ADA, and FRα expression assessments. Part 1 Dose Escalation will recruit about 25 patients per dose regimen (QW; Q2W; Q3W). The first stage of Part 2 (Dose Expansion) will recruit about 15 patients per tumor group expansion cohort. The study is actively enrolling in the US and currently recruiting in Q2W Cohort 201 and Q3W Cohort A. QW Cohorts 1-3 and Q2W Cohort 101 are complete. Clinical trial information: NCT05001282. Citation Format: Wen Wee Ma, Anthony Tolcher, Cesar A. Perez, Douglass Orr, Erika Hamilton, Yujie Zhao, Yonina Murciano-Goroff, Carey Anders, Gregory P. Adams, Catherine W. Reddick, Eliel Bayever. ELU-FRα-1: a study to evaluate ELU001 in patients with solid tumors that overexpress folate receptor alpha (FRα) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT255.

Abstract Background: Radiation is a potent inducer of DNA double-strand breaks, and ribonucleotide reductase (RNR) is the rate-limiting enzyme in the synthesis and repair of DNA, making RNR-targeted therapy a rationale therapeutic strategy for radiosensitization. ETCTN 10388 (NCT04234568) evaluated safety and efficacy of the combination of lutetium 177 DOTATATE, a beta-emitting radionuclide in combination with triapine, a ribonucleotide reductase (RNR) inhibitor. Method: This study was a multicenter phase 1 dose escalation trial [using the Bayesian optimal interval design (BOIN)] of triapine in combination with fixed dose lutetium Lu 177 DOTATATE for well-differentiated somatostatin receptor-positive gastroenteropancreatic neuroendocrine tumor (GEP-NETs) after the failure of at least one line of prior systemic cancer treatment with an expansion cohort at the recommended phase 2 dose (RP2D). Oral triapine (100mg, 150mg, 200mg) was administered once daily on days 1-14 and Lu-177 DOTATATE [200 mCi] intravenously on day 1 of every 56-day cycle. A total of 4 cycles were administered. Response and adverse effects were assessed per RECIST and CTCAE 5.0, respectively. Exploratory correlative studies included tumor somatic and germline mutation testing, RNA sequencing, pharmacokinetics, deoxynucleosides and circulating cell free DNA analysis. Primary endpoints were safety and RP2D. Results: Overall, 31 patients were enrolled between 6 sites, 15 in the dose escalation phase and 16 in the dose expansion phase. Adverse events (AE) were assessed in all 31 patients per CTCAE 5.0. One DLT in dose level 1, seven DLTs in dose level 2, and one grade 5 DLT in dose level 3 were observed. The RP2D of the combination is triapine 150 mg QD (dose level 2) on days 1-14 in combination with Lu-177 DOTATATE on day 1 of every 56-day cycle. Detailed safety and adverse event data will be presented at the meeting. There were 28 patients evaluable for efficacy, of which 6 (21%) achieved a partial response. At 12 months, 6 patients had progressed, while 22 (86%) remained progression free. Median PFS has not been reached. PK data were available for 12 patients enrolled in the dose escalation cohort. The geometric mean (SD) AUC0-inf was 1159 (1.22) µg/L•h for the 100mg dose level and 1862 (1.76) µg/L•h for the 150 mg dose level, suggesting that exposure increased with dose, and inter-patient variability was as expected for an oral agent. Conclusion: The combination of triapine and Lu-177 DOTATATE was safe with preliminary efficacy signals, which will be further evaluated in ETCTN 10558, a randomized phase 2 study that is comparing the effectiveness of triapine and Lu-177 DOTATATE to Lu-177 DOTATATE alone. Citation Format: Aman Chauhan, Susanne Arnold, Jill Kolesar, William Carson, Heidi Weiss, Rani Jayswal, Donglin Yan, Riham El Khouli, Aman Khurana, Jan Beumer, Heloisa Soares, Mary Mulcahy, Thorvardur Halfdanarson, Daneng Li, Heather Jacene, Percy Ivy, Elise Kohn, John Wright, Larry Rubinstein, Zeta Chow, Piotr Rychahou, Mark B. Evers, Charles Kunos, Lowell Anthony, Bhavana Konda. ETCTN 10388: a first in human phase I trial of triapine and lutetium Lu 177 DOTATATE in well-differentiated somatostatin receptor-positive gastroenteropancreatic neuroendocrine tumors (GEP-NETs) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT194.

Abstract Introduction: ATRi and PARPi combinations kill tumor cells via synergistic modulation of complementary DDR pathways but clinical utility is limited by overlapping toxicities. A genome-wide CRISPR-Cas9 screen identified DDR alterations that sensitize tumors to the ATRi camonsertib (cam) plus PARPi. Based on preclinical models, tolerability and efficacy of cam plus PARPi given intermittently at low doses in pts with solid tumors with DDR alterations, including BRCA-mutated PARPi-resistant cancers, was evaluated. Methods: Pts (≥ 18 yrs) with relapsed/refractory (r/r) solid tumors with DDR alterations were treated with cam plus talazoparib (tala), niraparib (nira), or olaparib (ola) in 2 phase I trials (NCT04497116, NCT04972110). An adaptive BOIN design was used to optimize dose/schedule. Endpoints were safety, recommended phase II dose (RP2D), pharmacokinetics (PK), response (RECIST v1.1 [confirmed/unconfirmed], CA 125, or PSA), clinical benefit rate (CBR; RECIST/tumor marker response or treatment duration ≥ 16 wk), and ctDNA molecular response rate (MRR; best reduction in mean variant allele frequency [mVAF] ≥ 50%). Results: As of Nov 2022, 99 pts were enrolled (61 with ≥ 3 prior lines of therapy, 36 PARPi-pretreated); 43, 27, 29 pts in tala, nira, and ola combinations, respectively. Tumors included ovarian (n=20), prostate (n=13), breast (n=17), bile duct (n=3); most common genotypes were ATM (n=26), BRCA1 (n=19), and BRCA2 (n=33). Grade 3+ toxicities included reversible myelosuppression (neutropenia, anemia, and thrombocytopenia in 35%, 28%, and 14% of pts overall; 33%, 16%, and 11% at preliminary RP2Ds), fatigue (3%), and alkaline phosphatase increase (2%). Two pts discontinued treatment due to drug-related toxicity. Forty pts remain on therapy, up to 63 wks. Preliminary RP2Ds: cam 80 mg QD (d 5-7) + tala 0.25 mg QD, 1 wk on/1 wk off; cam 80 mg QD + nira 100 mg QD, 2 d on/5 d off; cam 50 mg QD + ola 100 mg BID, 3 d on/4 d off. As of abstract submission, response rate was 13% in 85 evaluable pts; CBR was 49%. Responders included pts with ovarian (n=6), bile duct (n=2), and breast, pancreatic, and carcinoma of unknown primary (n=1 each) cancers harboring alterations in BRCA1/2 (n=9), IDH1 (n=1), and ATM (n=1). Of 30 evaluable PARPi-pretreated pts, response rate was 23% and CBR was 52%. MRR was 64% (14/22 evaluable); change in mVAF correlated with a change in target lesion size (r=0.63, P=0.001). PK of each drug in the combination was consistent with respective monotherapy PK. Conclusion: Combination of cam plus PARPi at low doses on intermittent schedules was generally well-tolerated with clinical activity in DDR-aberrant tumors, including those pretreated with PARPi. RP2D optimization and translational correlative studies are ongoing. Citation Format: Timothy A. Yap, Siddhartha Yadav, Benjamin Herzberg, Benedito A. Carneiro, Elisa Fontana, Martin Højgaard, Michael J. Pishvaian, Ruth Plummer, Theresa L. Werner, Vaibhav Sahai, Stephanie Lheureux, Elizabeth K. Lee, Niharika B. Mettu, Gregory M. Cote, Joseph D. Schonhoft, Victoria Rimkunas, Ian M. Silverman, Marisa Wainszelbaum, Gerson Peltz, Adrian J. Fretland, Kezhen Fei, Danielle Ulanet, Insil Kim, Maria Koehler, Ezra Rosen, Michael Cecchini. Safety and efficacy of three PARP inhibitors (PARPi) combined with the ataxia telangiectasia- and Rad3-related kinase inhibitor (ATRi) camonsertib in patients (pts) with solid tumors harboring DNA damage response (DDR) alterations [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT018.

Abstract Background: Isocitrate dehydrogenase 1/2 (IDH1/2) is mutated in a subset of cholangiocarcinoma (CCA), gliomas, and other solid tumors. LY3410738 is a potent, selective, covalent, dual inhibitor of IDH1/2 mutations (IDH1/2m). LY3410738 binds covalently at a novel binding site, enabling continued potency in preclinical models in the setting of second site IDH resistance mutations. We present initial results from the first-in-human phase 1 study of oral LY3410738 in patients (pts) with IDH1/2m CCA, and IDH1m glioma or other solid tumors. Methods: Dose escalation (3+3 design) evaluated LY3410738 monotherapy in advanced IDHm CCA and other solid tumors (NCT04521686). Key objectives included determining the RP2D, safety, PK, PD (inhibition of plasma D-2-HG), and preliminary antitumor activity. Results: As of 28 July 2022, 80 pts including 42 with CCA (33 IDH1m, 9 IDH2m), 27 with glioma (IDH1m), and 11 other tumor types (IDH1m) received LY3410738 dosed at 25-600 mg QD or 300 mg BID. Pts were median 52 years of age (range, 23-80) with a median of 2 prior therapies (range, 1-7). 19% of CCA pts had received prior IDH1 inhibitor. Median time on treatment was 3.7 months (range, 0.1-19). No DLTs or treatment related deaths were observed; the MTD was not reached. Treatment emergent adverse events (TEAEs) ≥15% included nausea (35%), vomiting (21%), and decreased appetite (19%) and were mostly grade 1-2. Most frequent grade ≥3 TEAEs &gt;2% were anemia (4%), cholangitis (3%), headache (3%), decreased lymphocyte count (3%), and hyponatremia (3%). LY3410738 exposure was dose proportional. In pts with IDH1m cancers, LY3410738 achieved sustained D-2-HG inhibition at all dose levels, including in pts who received prior IDH1 inhibitor. In pts with IDH2m cancers, a higher dose (≥150 mg daily dose) was required for D-2-HG inhibition. Among the 42 pts with R/R CCA, the best response included 1 PR and 22 SD. Of the 22 glioma pts with contrast enhancing tumors, best response included 3 PR and 9 SD. Conclusions: LY3410738 demonstrated a favorable safety profile with potent and sustained D-2-HG inhibition in pts with IDH1/2m advanced solid tumors. Consistent with the expectations for IDH inhibitor monotherapy in this setting, CCA and glioma pts exhibited prolonged stable disease. RP2D evaluation is ongoing. Updated data on LY3410738 monotherapy will be presented at the meeting. Citation Format: Jordi Rodon, Lipika Goyal, Teresa Macarulla Mercade, Masafumi Ikeda, Shunsuke Kondo, Do-Youn Oh, Li-Yuan Bai, Makoto Ueno, Antoine Italiano, Kyriakos Papadopoulos, David Spigel, Sani H. Kizilbash, Rasha Cosman, Joon Oh Park, Li-Tzong Chen, Tomoya Yokota, Anita A. Turk, Chih-Yi Liao, Rachna Shroff, Anthony El-Khoueiry, Taroh Satoh, Antoine Hollebecque, Mitesh J. Borad, Nilofer Azad, Kurt A. Jaeckle, Herbert H. Loong, Jorge Adeva, Wei Peng Yong, Junjie Zhao, Hui Liu, Anna M. Szpurka, Ivelina Gueorguieva, Kamnesh R. Pradhan, Xiaojian Xu, James J. Harding. A first-in-human phase 1 study of LY3410738, a covalent inhibitor of mutant IDH, in advanced IDH-mutant cholangiocarcinoma and other solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT098.

Abstract Purpose: Treatment options are limited beyond JAK inhibitors for patients with primary myelofibrosis (MF) or secondary MF. Preclinical studies have revealed that PI3Kδ inhibition cooperates with ruxolitinib, a JAK1/2 inhibitor, to reduce proliferation and induce apoptosis of JAK2V617F-mutant cell lines. Patients and Methods: In a phase I dose-escalation and -expansion study, we evaluated the safety and efficacy of a selective PI3Kδ inhibitor, umbralisib, in combination with ruxolitinib in patients with MF who had a suboptimal response or lost response to ruxolitinib. Enrolled subjects were required to be on a stable dose of ruxolitinib for ≥8 weeks and continue that MTD at study enrollment. The recommended dose of umbralisib in combination with ruxolitinib was determined using a modified 3+3 dose-escalation design. Safety, pharmacokinetics, and efficacy outcomes were evaluated, and spleen size was measured with a novel automated digital atlas. Results: Thirty-seven patients with MF (median age, 67 years) with prior exposure to ruxolitinib were enrolled. A total of 2 patients treated with 800 mg umbralisib experienced reversible grade 3 asymptomatic pancreatic enzyme elevation, but no dose-limiting toxicities were seen at lower umbralisib doses. Two patients (5%) achieved a durable complete response, and 12 patients (32%) met the International Working Group-Myeloproliferative Neoplasms Research and Treatment response criteria of clinical improvement. With a median follow-up of 50.3 months for censored patients, overall survival was greater than 70% after 3 years of follow-up. Conclusions: Adding umbralisib to ruxolitinib in patients was well tolerated and may resensitize patients with MF to ruxolitinib without unacceptable rates of adverse events seen with earlier generation PI3Kδ inhibitors. Randomized trials testing umbralisib in the treatment of MF should be pursued.