Dowlati, Afshin

Background Novel treatment options are required in patients with platinum-resistant ovarian cancer (PROC). Myeloid-derived suppressor cells promote a hostile tumor microenvironment and are associated with worse clinical outcomes in PROC. We evaluated the safety and preliminary efficacy of PY159, an agonist antibody to Triggering receptor expressed on myeloid cells-1 (TREM1) that reprograms immunosuppressive intratumoral myeloid cells, and PY314, an antagonist antibody to Triggering receptor expressed on myeloid cells-2 (TREM2) that depletes tumor-associated macrophages, as single agents and in combination with pembrolizumab in subjects with PROC. Methods PY159 and PY314 were individually evaluated in patients with PROC. Patients were treated with monotherapy (PY159 3 mg/kg or PY314 10 mg/kg), based on the recommended dose for expansion derived from the phase 1a studies. At the time of first progression, patients could continue study drug and crossover to combination therapy with pembrolizumab (200 mg) every 3 weeks at the discretion of the investigator. Disease assessment by Response Evaluation Criteria in Solid Tumor version 1.1 was performed every 6 weeks. Results 17 patients were enrolled in the PY159 study (median age 67, range 22–77; median prior therapies 6, range 2–18) and 16 patients in PY314 (median age 65.5, range 49–81; median prior therapies 4, range 2–10). 7 patients in PY159 and 8 patients in PY314 crossed over to combination therapy. Safety events included the following: treatment-related adverse events occurred in 15 patients (88.2%) in PY159 and 9 patients (56.3%) in PY314. Infusion-related reactions occurred in 6 patients (35.3%) in PY159 and 3 patients (18.8%) in PY314. Immune-related adverse events occurred in 13 patients (76.5%) in PY159 (arthralgias) and 1 patient (6.3%) in PY314 (diarrhea). Serious adverse events occurred in 6 patients (36.3%) in PY159 (1 related) and 12 patients (75%) in PY314 (all unrelated). The best radiographic response in PY159 was stable disease in 8/16 patients (50%; median 16 weeks, range 9–33), and in PY314, it was stable disease in 8/16 patients (50%; median 12 weeks, range 6–36). Median PFS was 2.76 months and 2.69 months in PY159 and PY314, respectively. There were no responses in the crossover arm. Conclusions Both PY159 and PY314 were well tolerated, with an acceptable safety profile, as both single agents and in combination with pembrolizumab. Both agents warrant further investigation in heavily pretreated PROC.

Background: Bimiralisib is a pan-PI3K/mTOR inhibitor demonstrating antitumor efficacy in preclinical models. The objectives of this study were to identify a maximum tolerated dose (MTD), pharmacokinetics (PK), a dosing schedule, and adverse events (AEs) in patients with advanced solid tumors. Patients and Methods: Patients received oral bimiralisib to determine the MTD of one continuous (once daily) and two intermittent schedules (A: Days 1, 2 weekly; B: Days 1, 4 weekly) until progression or unacceptable AEs occurred. Results: The MTD for the continuous schedule was 80 mg, with grade three fatigue as the dose-limiting toxicity (DLT). No MTD was reached with intermittent schedules, with only one DLT in schedule B. PK analysis suggested that 140 mg (schedule A) was within the biologically active dose range and was selected for further exploration. The most frequent treatment-emergent AEs were hyperglycemia (76.2%) in the continuous schedule, and nausea (56–62.5%) in schedules A and B. The most frequent treatment-emergent > grade three AE for all schedules combined was hyperglycemia (28.6%, continuous schedule; 12.0%, schedule A; 12.5%, schedule B). There was one partial response in a head and neck squamous cancer patient with a NOTCH1T1997M mutation. Conclusions: Bimiralisib demonstrated a manageable AE profile consistent with this compound class. Intermittent schedules had fewer > grade three AEs, while also maintaining favorable PK profiles. Intermittent schedule A is proposed for further development in biomarker-selected patient populations.

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Small Cell Lung Cancer (SCLC) provide recommended management for patients with SCLC, including diagnosis, primary treatment, surveillance for relapse, and subsequent treatment. This selection for the journal focuses on metastatic (known as extensive-stage) SCLC, which is more common than limited-stage SCLC. Systemic therapy alone can palliate symptoms and prolong survival in most patients with extensive-stage disease. Smoking cessation counseling and intervention should be strongly promoted in patients with SCLC and other high-grade neuroendocrine carcinomas. The “Summary of the Guidelines Updates” section in the SCLC algorithm outlines the most recent revisions for the 2022 update, which are described in greater detail in this revised Discussion text.

Abstract Purpose: Romidepsin dosing recommendations for patients with malignancy and varying degrees of hepatic dysfunction was lacking at the time of regulatory approval for T-cell lymphoma. We conducted a multicenter phase I clinical trial (ETCTN-9008) via the NCI Organ Dysfunction Working Group to investigate safety, first cycle MTD, and pharmacokinetic profile of romidepsin in this setting. Patients and Methods: Patients with select advanced solid tumors or hematologic malignancies were stratified according to hepatic function. Romidepsin was administered intravenously on days 1, 8, and 15 of a 28-day cycle and escalation followed a 3 + 3 design in moderate and severe impairment cohorts. Blood samples for detailed pharmacokinetic analyses were collected after the first dose. Results: Thirty-one patients received one dose of romidepsin and were evaluable for pharmacokinetic analyses in normal (n = 12), mild (n = 8), moderate (n = 5), and severe (n = 6) cohorts. Adverse events across cohorts were similar, and dose-limiting toxicity occurred in two patients (mild and severe impairment cohorts). The MTD was not determined because the geometric mean AUC values of romidepsin in moderate (7 mg/m2) and severe (5 mg/m2) impairment cohort were 114% and 116% of the normal cohort (14 mg/m2). Conclusions: Data from the ETCTN-9008 trial led to changes in the romidepsin labeling to reflect starting dose adjustment for patients with cancer and moderate and severe hepatic impairment, with no adjustment for mild hepatic impairment.

3583 Background: The novel curaxin CBL0137 intercalates into DNA, interfering with histone/DNA binding. Consequent trapping of histone chaperone FACT leads to MYC, NF-kB, and HSF1 inhibition, p53 activation, and an IFN response. CBL0137 shows broad nonclinical antitumor activity (Gasparian et al. Sci Transl Med. 2011; 3(95):95ra74). Methods: This dose-ranging study assessed the CBL0137 maximum tolerated dose (MTD) and recommended Phase 2 dose (RP2D) and CBL0137 safety, pharmacokinetics (PK), and efficacy in adults with advanced treatment-refractory solid tumors. CBL0137 was administered IV on Days 1, 8, and 15 of repeated 28-day cycles until progressive disease (PD) or unacceptable toxicity. Doses were escalated using a 3+3 design based on Cycle 1 dose-limiting toxicities (DLTs). PK was assessed through 168 hours after Day 1. Efficacy was evaluated every 8 weeks. Results: The study enrolled 83 pts (M/F [n] = 49/34; median [range] age = 64 [33-85] years; ECOG status [n] = 1/2 [32/51]), with cancer types (n) of colorectal (23), prostate (7), glioblastoma (6), liver (6), non-small-cell (5), and others (36) across 17 dose levels from 10 to 700 mg/m2/infusion. Durations of therapy ranged to 24 months. Cycle 1 DLTs (n type) were observed at 240 mg/m2 (1 Gr 3 photosensitivity), 400 mg/m2 (1 Gr 3 anemia), 700 mg/m2 (1 Gr 4 thrombocytopenia, 1 Gr 4 neutropenia/Gr 4 thrombocytopenia), and 650 mg/m2 (1 Gr 3 thrombocytopenia, 1 Gr 4 neutropenia/Gr 3 thrombocytopenia). Nausea and vomiting were successfully prevented with dexamethasone/serotonin antagonists. Photosensitization was effectively managed with sun protection. Peripheral venous thrombosis required central vein infusion in subjects with glioblastoma. PK showed dose-proportional increases in plasma CBL0137 area under the concentration-time curve (AUC), a high mean (range) volume of distribution (Vd) of 1,030 (655-1460) L/m2 consistent with extensive tissue distribution and DNA intercalation, and an average mean (range) half-life (t1/2) of 24.7 (10.3-40.7) hours without dose dependence. The best response was stable disease: 2 pts with liver cancer had tumor control for 9 and 24 months and a maximum tumor regression of 10%; 2 pts with prostate cancer had tumor regressions by 11% and 22%; 1 pt with uterine cancer had a 20% tumor regression. Conclusions: CBL0137 administered IV was generally well tolerated with manageable toxicities The MTD and RP2D were estimated at 540 mg/m2 due to myelosuppressive DLTs. PK were predictable. Preliminary evidence of antitumor activity supports Phase 2 testing. Clinical trial information: NCT01905228 .

Abstract Background: Bimiralisib is a balanced dual panPI3K/mTOR inhibitor, which demonstrated anti-cancer activity in a number of preclinical models. Pharmacokinetic (PK) data suggested that intermittent targeting of the PI3K/mTOR pathway could be preferable to continuous daily dosing. Preclinical models in squamous cell head and neck cancer (SCCHN) demonstrated that NOTCH1 Loss of Function (LoF) mutations were associated with efficacy of bimiralisib and other PI3K inhibitors. Methods: We conducted a first-in-human dose-escalation study (3+3 design) to identify the maximum tolerated dose (MTD), recommended phase 2 dose (RP2D), dose-limiting toxicities (DLT) and overall safety (CTCAE v4) of bimiralisib administered either as a continuous (80 mg – 120 mg daily) or one of two intermittent schedules (schedule A: twice weekly 80 mg – 200 mg on Day 1 and 2, or schedule B: twice weekly 80mg – 200 mg on Day 1 and 4) until disease progression or unacceptable adverse events (AEs). Eligible patients had histologically confirmed solid cancers refractory to standard therapies, ECOG <1, life expectancy >12 weeks, adequate bone marrow, liver, and renal functions, HgbA1c <7%, and fasting plasma glucose < 7.0mmol/L. Tumor responses were evaluated according to RECIST v1.1 every 6 weeks. PK and blood biomarkers were analyzed. Results: 70 patients (female, 70%; white, 93%; median age 57 years [range, 49-65]) with heavily pretreated advanced solid cancers were enrolled (continuous schedule, 21; intermittent schedule A, 25; intermittent schedule B, 24). The MTD for the continuous schedule was established as 80 mg daily. For all treatment groups, DLTs included grade 2 and 3 fatigue. Clinically significant treatment-related AEs included fatigue in the continuous schedule, none in the intermittent schedule A and diarrhea, hyperglycemia in the intermittent schedule B. Intermittent schedules A and B did not reach the MTD, and after review of PK data, 140 mg administered in schedule A was selected as the RP2D for further exploration. Day 1 peak plasma concentration proportionally increased with increasing doses of bimiralisib only up to 140mg. Weekly AUC on intermittent dosing at all dose levels studied were considerably lower than continuous daily dosing at 80mg. There was one partial response (PR, -85% per RECIST) in a heavily pretreated patient with SCCHN and NOTCH1 LoF mutation, which was maintained for 8.2 months until death from pulmonary artery rupture in the setting of known fistula (assessed as unrelated to bimiralisib). In addition, 30 (42.9%) pts achieved stable disease (SD) including one with anal SCC carrying a NOTCH1 LoF mutation. SD > 6 months was observed in five pts (23.8%) in continuous schedule, 12 (48%) in intermittent schedule A, and 13 (54.2%) in intermittent schedule B. Results on patients, who consented to the serial circulating tumor DNA collection will be presented. Conclusions: Bimiralisib was well tolerated and RP2D of 140 mg given orally twice weekly on Days 1 and 2 was selected for further studies. In agreement with our preclinical models, there was an encouraging activity in a SCCHN patient with NOTCH1 LoF mutation and this observation is now being validated in a proof-of-concept phase 2 study (NCT03740100). Citation Format: Filip Janku, Faye M. Johnson, Mateusz Opyrchal, Afshin Dowlati, Cinta Hierro, Martin Forester, Sarah P. Blagden, Andreas Wicki, Debora Schmitz, Alex A. Adjei. Oral dual PI3K/mTOR inhibitor bimiralisib demonstrates tolerability and a signal of activity in head and neck squamous cell cancer with NOTCH1 loss-of-function mutation [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 B109. doi:10.1158/1535-7163.TARG-19-B109

Abstract Lessons Learned Targeted therapy options for SCLC patients are limited; no agent, thus far, has resulted in a strategy promising enough to progress to phase III trials. Linsitinib, a potent insulin growth factor-1-receptor tyrosine kinase inhibitor, may be one agent with activity against SCLC. Despite lack of a reliable predictive biomarker in this disease, which may have partly contributed to the negative outcome reported here, linsitinib, although safe, showed no clinical activity in unselected, relapsed SCLC patients. Background. Treatment of relapsed small-cell lung cancer (SCLC) remains suboptimal. Insulin growth factor-1 receptor (IGF-1R) signaling plays a role in growth, survival, and chemoresistance in SCLC. Linsitinib is a potent IGF-1R tyrosine kinase inhibitor that potentially may be active against SCLC. Methods. In this phase II study, 8 eligible patients were randomly assigned in a 1:2 ratio to topotecan (1.5 mg/m2 intravenously or 2.3 mg/m2 orally, daily for 5 days for 4 cycles) or linsitinib (150 mg orally twice daily until progression). The primary endpoint was progression-free survival. Patients with relapsed SCLC, platinum sensitive or resistant, performance status (PS) 0–2, and adequate hematologic, renal, and hepatic function were enrolled. Patients with diabetes, cirrhosis, and those taking insulinotropic agents were excluded. Crossover to linsitinib was allowed at progression. Results. Fifteen patients received topotecan (8 resistant, 3 with PS 2) and 29 received linsitinib (16 resistant, 5 with PS 2). Two partial responses were observed with topotecan. Only 4 of 15 patients with topotecan and 1 of 29 with linsitinib achieved stable disease. Median progression-free survival was 3.0 (95% confidence interval [CI], 1.5–3.6) and 1.2 (95% CI, 1.1–1.4) months for topotecan and linsitinib, respectively (p = .0001). Median survival was 5.3 (95% CI, 2.2–7.6) and 3.4 (95% CI, 1.8–5.6) months for topotecan and linsitinib, respectively (p = .71). Grade 3/4 adverse events (>5% incidence) included anemia, thrombocytopenia, neutropenia/leukopenia, diarrhea, fatigue, dehydration, and hypokalemia for topotecan; and thrombocytopenia, fatigue, and alanine aminotransferase/aspartate aminotransferase elevations for linsitinib. Conclusion. Linsitinib was safe but showed no clinical activity in unselected, relapsed SCLC patients.

Abstract Purpose: This randomized phase II study was initially designed to test the activity of two dose schedules of lapatinib (GW572016H), an oral, reversible, dual tyrosine kinase inhibitor of epidermal growth factor receptor (EGFR) and human EGFR-2 (HER2/neu; HER2), in chemotherapy-naive patients with non–small cell lung cancer (NSCLC); it was later amended to target patients with bronchioloalveolar carcinoma or no smoking history. Experimental Design: Patients with good performance status and recurrent or metastatic NSCLC were randomized to lapatinib (orally, 1,500 mg once daily or 500 mg twice daily) until progression or intolerance. Patients could have had a maximum of one prior systemic therapy (chemotherapy or biological therapy) for NSCLC. Safety and activity were assessed every 4 and 8 weeks, respectively. Tumors were analyzed for EGFR and HER2 mutations and/or amplifications. Results: Of 75 patients in the nontargeted population, 1 (1.3%) had partial response and 16 (21%) had stable disease of ≥24 weeks. No complete or partial responses were observed in 56 patients in the targeted population; 14 (25%) had stable disease of ≥24 weeks. No responses were seen in three patients with EGFR mutations and five with EGFR gene amplification. No mutations in HER2 were found. One of two patients with HER2 amplification had a 51% decrease in tumor size; however, this response was unconfirmed. The most common adverse events were grade 1 or 2 diarrhea, rash, fatigue, nausea, and anorexia. Adverse events were similar across dosing regimens. Conclusions: Lapatinib was well tolerated, with no notable difference in toxicity between treatment groups. Lapatinib monotherapy did not induce a significant number of tumor regressions in NSCLC. Further studies may be warranted to determine whether lapatinib is active in combination with other agents in the treatment of NSCLC. Clin Cancer Res; 16(6); 1938–49