Safety, tolerability and efficacy of agonist anti-CD27 antibody (varlilumab) administered in combination with anti-PD-1 (nivolumab) in advanced solid tumors.

BACKGROUND: Phase 1/2 dose-escalation and expansion study evaluating varlilumab, a fully human agonist anti-CD27 mAb, with nivolumab in anti-PD-1/L1 naïve, refractory solid tumors. METHODS: Phase 1 evaluated the safety of varlilumab (0.1-10 mg/kg) with nivolumab (3 mg/kg) administered once every 2 weeks. Phase 2 evaluated varlilumab regimens (3 mg/kg once every 2 weeks, 3 mg/kg once every 12 weeks, and 0.3 mg/kg once every 4 weeks) with nivolumab 240 mg once every 2 weeks in tumor-specific cohorts. Primary objective was safety; key clinical endpoints included objective response rate (ORR) and overall survival rate at 12 months (OS12) (glioblastoma (GBM) only). Exploratory objectives included determination of effects on peripheral blood and intratumoral immune signatures. RESULTS: 175 patients were enrolled (36 in phase 1 and 139 in phase 2). Phase 1 dose-escalation proceeded to the highest varlilumab dose level without determining a maximum tolerated dose. In phase 2, ORR were ovarian 12.5%, squamous cell carcinoma of the head and neck 12.5%, colorectal cancer 5%, and renal cell carcinoma 0%; GBM OS12 was 40.9%. Increased tumor PD-L1 and intratumoral T cell infiltration were observed in ovarian cancer patients, with increases of ≥5% associated with better progression-free survival. The most common treatment related adverse events were fatigue (18%), pruritus (16%), and rash (15%). CONCLUSION: Varlilumab and nivolumab were well tolerated, without significant toxicity beyond that expected for each agent alone. Clinical activity was observed in patients that are typically refractory to anti-PD-1 therapy, however, overall was not greater than expected for nivolumab monotherapy. Treatment was associated with proinflammatory changes in the tumor microenvironment, particularly in ovarian cancer where the changes were associated with better clinical outcomes. TRIAL REGISTRATION NUMBER: NCT02335918.

Phase Ib Study of the BET Inhibitor GS-5829 as Monotherapy and Combined with Enzalutamide in Patients with Metastatic Castration-Resistant Prostate Cancer.

PURPOSE: A phase Ib study (1604) was conducted to evaluate the safety and efficacy of GS-5829, an oral bromodomain and extraterminal inhibitor, alone and in combination with enzalutamide in metastatic castration-resistant prostate cancer (mCRPC). A phase I study (1599) in solid tumors/lymphoma was also conducted. PATIENTS AND METHODS: Men with confirmed mCRPC and disease progression despite abiraterone and/or enzalutamide treatment were enrolled in a 3 + 3 dose escalation paradigm starting at 2 mg daily with GS-5829 alone and in combination with 160 mg daily enzalutamide. The primary efficacy endpoint was nonprogression rate at week 24; secondary endpoints included prostate-specific antigen reduction from baseline, progression-free survival, and GS-5829 pharmacokinetics (PK). PK and safety were also evaluated in Study 1599. RESULTS: Thirty-one men, with a median of five prior regimens, received at least 1 dose of study drug in Study 1604. Treatment-emergent adverse events (TEAE) were reported in 94% of patients; 16% discontinued for TEAEs. There were no dose-dependent increases in the AUCtau or Cmax after once-daily administration of GS-5829 2 to 9 mg, and biomarkers CCR2 inhibition and HEXIM1 induction were increased only at higher doses of monotherapy. A high degree of interpatient variability existed across all doses in PK and pharmacodynamic parameters. The proportion with nonprogression at week 24, estimated by Kaplan-Meier model, was 25% (95% confidence interval, 10-42) for all treated patients. CONCLUSIONS: GS-5829 was generally tolerated but demonstrated limited efficacy and lack of dose proportional increases in plasma concentrations in patients with mCRPC.

Phase III Study to Evaluate Efficacy and Safety of Andecaliximab With mFOLFOX6 as First-Line Treatment in Patients With Advanced Gastric or GEJ Adenocarcinoma (GAMMA-1).

PURPOSE: Andecaliximab (ADX) is a monoclonal antibody that inhibits matrix metalloproteinase 9, an extracellular enzyme involved in matrix remodeling, tumor growth, and metastases. A phase I and Ib study of modified oxaliplatin, leucovorin, and fluorouracil (mFOLFOX6) with ADX revealed encouraging antitumor activity in patients with gastric or gastroesophageal junction (GEJ) adenocarcinoma. MATERIALS AND METHODS: This phase III, randomized, double-blinded, placebo (PBO)-controlled multicenter study investigated the efficacy and safety of mFOLFOX6 with and without ADX in patients with untreated human epidermal growth factor receptor 2-negative gastric or GEJ adenocarcinoma. Random assignment was 1:1 to mFOLFOX6 + ADX or mFOLFOX6 + PBO. ADX/PBO 800 mg was infused on days 1 and 15 of each 28-day cycle. Protocol therapy was given until disease progression or intolerance. The primary end point was overall survival (OS), and secondary end points were progression-free survival (PFS), objective response rate (RECIST 1.1), and safety. RESULTS: Between September 2015 and May 2017, 432 patients were randomly assigned, 218 to ADX and 214 to PBO. The median OS was 12.5 versus 11.8 months in the ADX and PBO groups, respectively. The median PFS was 7.5 versus 7.1 months in the ADX and PBO groups, respectively. The objective response rate was 51% in the ADX group and 41% in the PBO group. Among the subgroup analyses, patients of age ≥ 65 years had an improved OS and PFS with ADX versus PBO; the P values and CIs were not adjusted for multiplicity. There were no meaningful differences in the safety profile of the ADX versus PBO groups. CONCLUSION: The addition of ADX to mFOLFOX6 did not improve OS in unselected patients with untreated human epidermal growth factor receptor 2-negative gastric or GEJ adenocarcinoma.

Effects of Rovalpituzumab Tesirine on Ventricular Repolarization in Patients With Small-Cell Lung Cancer.

Small cell lung cancer (SCLC) is a leading cause of cancer death worldwide, with few treatment options. Rovalpituzumab tesirine (Rova-T) is an antibody-drug conjugate that targets delta-like 3 on SCLC cells to deliver a cytotoxic payload directly to tumor cells. In this study, the cardiac safety profile of Rova-T was assessed by evaluating changes in QT interval, electrocardiogram (ECG) waveform, heart rate, and proarrhythmic adverse events (AEs) after treatment with Rova-T in patients with previously treated extensive-stage SCLC. Patients underwent ECG monitoring for 2 weeks after each of 2 i.v. infusions of 0.3 mg/kg Rova-T over 30 minutes, administered 6 weeks apart. Forty-six patients received at least one dose of Rova-T. At the geometric mean Rova-T maximum serum concentration of 7,940 ng/mL, ECG monitoring showed no significant changes in the Fridericia-corrected QT (QTcF) interval; the upper limit of the 2-sided 90% confidence interval did not exceed 10 msec for any time point. There were no clinically significant changes in QRS or PR intervals, ECG waveforms, or heart rate after Rova-T administration. All patients experienced a treatment-emergent AE (TEAE); 78% had a grade ≥ 3 TEAE, 59% had a serious TEAE, and 41% had a cardiac-related TEAE. The TEAEs that might signal proarrhythmia tendencies were uncommon. Confirmed partial responses were observed in 24% of patients. Based on the evaluation of ECG data collected in this study from patients treated with Rova-T at 0.3 mg/kg i.v. administered every 6 weeks, a QTcF effect of clinical concern can be excluded.

Safety and Efficacy of Andecaliximab (GS-5745) Plus Gemcitabine and Nab-Paclitaxel in Patients with Advanced Pancreatic Adenocarcinoma: Results from a Phase I Study.

BACKGROUND: Matrix metalloproteinase 9 (MMP9) expression in the tumor microenvironment is implicated in multiple protumorigenic processes. Andecaliximab (GS-5745), a monoclonal antibody targeting MMP9 with high affinity and selectivity, was evaluated in combination with gemcitabine and nab-paclitaxel in patients with advanced pancreatic adenocarcinoma. PATIENTS AND METHODS: This phase I study was completed in two parts: part A was a dose-finding, monotherapy phase that enrolled patients with advanced solid tumors, and part B examined andecaliximab in combination with chemotherapy in specific patient cohorts. In the cohort of patients with pancreatic adenocarcinoma (n = 36), andecaliximab 800 mg every 2 weeks was administered in combination with gemcitabine and nab-paclitaxel. Patients were treated until unacceptable toxicity, withdrawal of consent, disease progression, or death. Efficacy, safety, and biomarker assessments were performed. RESULTS: Andecaliximab combined with gemcitabine and nab-paclitaxel appeared to be well tolerated and did not demonstrate any unusual toxicities in patients with pancreatic adenocarcinoma. The most common treatment-emergent adverse events were fatigue (75.0%), alopecia (55.6%), peripheral edema (55.6%), and nausea (50.0%). Median progression-free survival was 7.8 months (90% confidence interval, 6.9-11.0) with an objective response rate of 44.4% and median duration of response of 7.6 months. Maximal andecaliximab target binding, defined as undetectable, andecaliximab-free MMP9 in plasma, was observed. CONCLUSION: Andecaliximab in combination with gemcitabine and nab-paclitaxel demonstrates a favorable safety profile and clinical activity in patients with advanced pancreatic adenocarcinoma. IMPLICATIONS FOR PRACTICE: The combination of andecaliximab, a novel, first-in-class inhibitor of matrix metalloproteinase 9, with gemcitabine and nab-paclitaxel in patients with advanced pancreatic adenocarcinoma provided a median progression-free survival of 7.8 months and objective response rate of 44.4%. The majority of systemic biomarkers related to matrix metalloproteinase 9 activity and immune suppression increased at 2 months, whereas biomarkers related to tumor burden decreased. Although this study demonstrates promising results with andecaliximab plus chemotherapy in patients with advanced pancreatic adenocarcinoma, andecaliximab was not associated with a survival benefit in a phase III study in patients with advanced gastric/gastroesophageal junction carcinoma.

Phase 1 dose-escalation study of momelotinib, a Janus kinase 1/2 inhibitor, combined with gemcitabine and nab-paclitaxel in patients with previously untreated metastatic pancreatic ductal adenocarcinoma.

Purpose Preclinical evidence suggests the importance of Janus activating kinase (JAK) and TANK-binding kinase 1 (TBK1) in pancreatic ductal adenocarcinoma (PDAC). We evaluated the safety and efficacy of momelotinib (MMB), a JAK1/2 inhibitor with additional activity against TBK1, plus albumin-bound paclitaxel + gemcitabine (nab-P + G), in patients with previously untreated metastatic PDAC. Experimental Design Patients were enrolled into five cohorts of increasing doses of MMB between 100 and 200 mg administered once or twice daily in combination with nab-P + G in 28-day cycles to determine maximum tolerated dose (MTD). Safety, efficacy, pharmacokinetics, and pharmacodynamics were assessed for all patients. Results Twenty-five patients were enrolled. Dose-limiting toxicities of Grade 3 diarrhea occurred in 1 patient each in the 100 and 200 mg MMB once-daily dose groups. MTD was not reached. The 200 mg MMB twice-daily was the maximum administered dose. Objective response rate was 28% (all partial responses), and 13 (52%) patients had a best response of stable disease. The most common adverse events (AEs) were fatigue (80%), nausea (76%), and anemia (68%). Grade 3 or 4 AEs, most commonly neutropenia (32%), were reported by 88% of patients, of which 44% were considered related to MMB. Pharmacokinetic analyses showed MMB concentrations were too low for TBK1 inhibition. Conclusions MMB was safe and well tolerated in combination with nab-P + G. As no OS or PFS benefit vs nab-P + G was apparent in context of suboptimal engagement of the target TBK1, this study does not support further development of MMB as a first-line therapy in pancreatic cancer.

Andecaliximab/GS-5745 Alone and Combined with mFOLFOX6 in Advanced Gastric and Gastroesophageal Junction Adenocarcinoma: Results from a Phase I Study.

Purpose: Matrix metalloproteinase-9 (MMP9) is implicated in protumorigenic processes. Andecaliximab (GS-5745, a monoclonal antibody targeting MMP9) was evaluated as monotherapy and in combination with mFOLFOX6.Patients and Methods: Three dosages of andecaliximab monotherapy [200, 600, and 1800 mg i.v. every 2 weeks (q2w)] were investigated in patients with advanced solid tumors (n = 13 in a 3+3 design). After determining a recommended dose, patients with advanced HER2-negative gastric/gastroesophageal junction (GEJ) adenocarcinoma (n = 40) received 800 mg andecaliximab + mFOLFOX6 q2w. Pharmacokinetics, pharmacodynamics, safety, and efficacy were assessed.Results: Andecaliximab monotherapy demonstrated no dose-limiting toxicity (DLT) in any cohort, displaying target-mediated drug disposition at the lowest dose (200 mg) and linear pharmacokinetics at higher doses. Based on target engagement, recommended doses for further study are 800 mg q2w or 1,200 mg q3w. Maximal andecaliximab target binding, defined as undetectable andecaliximab-free MMP9 in plasma, was observed in the gastric/GEJ adenocarcinoma cohort. We observed no unusual toxicity, although there were four deaths on study not attributed to andecaliximab treatment. In first-line patients (n = 36), median progression-free survival (PFS) was 9.9 months [95% confidence interval (CI), 5-13.9 months], and the overall response rate (ORR) was 50%. Among all patients (n = 40), median PFS was 7.8 (90% CI, 5.5-13.9) months, and ORR was 48%, with a median duration of response of 8.4 months.Conclusions: Andecaliximab monotherapy achieved target engagement without DLT. Andecaliximab + mFOLFOX6 showed encouraging clinical activity without additional toxicity in patients with HER2-negative gastric/GEJ adenocarcinoma. A phase III study evaluating mFOLFOX6 ± andecaliximab in this setting is ongoing. Clin Cancer Res; 24(16); 3829-37. ©2018 AACR.

Phase 2 Trial of Gemcitabine, Cisplatin, plus Ipilimumab in Patients with Metastatic Urothelial Cancer and Impact of DNA Damage Response Gene Mutations on Outcomes.

BACKGROUND: Chemotherapy may exert immunomodulatory effects, thereby combining favorably with the immune checkpoint blockade. The pharmacodynamic effects of such combinations, and potential predictive biomarkers, remain unexplored. OBJECTIVE: To determine the safety, efficacy, and immunomodulatory effects of gemcitabine and cisplatin (GC) plus ipilimumab and explore the impact of somatic DNA damage response gene alterations on antitumor activity. DESIGN, SETTING, AND PARTICIPANTS: Multicenter single arm phase 2 study enrolling 36 chemotherapy-naïve patients with metastatic urothelial cancer. Peripheral blood flow cytometry was performed serially on all patients and whole exome sequencing of archival tumor tissue was performed on 28/36 patients. INTERVENTION: Two cycles of GC followed by four cycles of GC plus ipilimumab. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was 1-yr overall survival (OS). Secondary endpoints included safety, objective response rate, and progression-free survival. RESULTS AND LIMITATIONS: Grade ≥3 adverse events occurred in 81% of patients, the majority of which were hematologic. The objective response rate was 69% and 1-yr OS was 61% (lower bound 90% confidence interval: 51%). On exploratory analysis, there were no significant changes in the composition and frequency of circulating immune cells after GC alone. However, there was a significant expansion of circulating CD4 cells with the addition of ipilimumab which correlated with improved survival. The response rate was significantly higher in patients with deleterious somatic DNA damage response mutations (sensitivity=47.6%, specificity=100%, positive predictive value=100%, and negative predictive value=38.9%). Limitations are related to the sample size and single-arm design. CONCLUSIONS: GC+ipilimumab did not achieve the primary endpoint of a lower bound of the 90% confidence interval for 1-yr OS of >60%. However, within the context of a small single-arm trial, the results may inform current approaches combining chemotherapy plus immunotherapy from the standpoint of feasibility, appropriate cytotoxic backbones, and potential predictive biomarkers. TRIAL REGISTRATION: ClinicalTrials.gov NCT01524991. PATIENT SUMMARY: Combining chemotherapy and immune checkpoint blockade in patients with metastatic urothelial cancer is feasible. Further studies are needed to refine optimal combinations and evaluate tests that might identify patients most likely to benefit.

Phase I/II Trial of Labetuzumab Govitecan (Anti-CEACAM5/SN-38 Antibody-Drug Conjugate) in Patients With Refractory or Relapsing Metastatic Colorectal Cancer.

Purpose The objectives were to evaluate dosing schedules of labetuzumab govitecan, an antibody-drug conjugate targeting carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5) for tumor delivery of 7-ethyl-10-hydroxycamptothecin (SN-38), in an expanded phase II trial of patients with relapsed or refractory metastatic colorectal cancer. Patients and Methods Eligible patients with at least one prior irinotecan-containing therapy received labetuzumab govitecan once weekly at 8 and 10 mg/kg, or two times per week at 4 and 6 mg/km on weeks 1 and 2 of 3-week repeated cycles. End points were safety, response, pharmacokinetics, and immunogenicity. Results Eighty-six patients who had undergone a median of five prior therapies (range, one to 13) were each enrolled into one of the four cohorts. On the basis of Response Evaluation Criteria in Solid Tumors 1.1, 38% of these patients had a tumor as well as plasma carcinoembryonic antigen reduction from baseline after labetuzumab govitecan treatment; one patient achieved a partial response with a sustained response spanning > 2 years, whereas 42 patients had stable disease as the best overall response. Median progression-free survival and overall survival were 3.6 and 6.9 months, respectively. The major toxicities (grade ≥ 3) among all cohorts were neutropenia (16%), leukopenia (11%), anemia (9%), and diarrhea (7%). The antibody-drug conjugate's mean half-life was 16.5 hours for the four cohorts. Anti-drug/anti-antibody antibodies were not detected. The two once-weekly dose schedules, showing comparable toxicity and efficacy, were chosen for further study. Conclusion Monotherapy with labetuzumab govitecan demonstrated a manageable safety profile and therapeutic activity in heavily pretreated patients with metastatic colorectal cancer, all with prior irinotecan therapy. Further studies of labetuzumab govitecan treatment alone or in combination with other therapies in earlier settings are indicated.

Therapy of Small Cell Lung Cancer (SCLC) with a Topoisomerase-I-inhibiting Antibody-Drug Conjugate (ADC) Targeting Trop-2, Sacituzumab Govitecan.

Purpose: We evaluated a Trop-2-targeting antibody conjugated with SN-38 in metastatic small cell lung cancer (mSCLC) patients.Experimental Design: Sacituzumab govitecan was studied in patients with pretreated (median, 2; range, 1-7) mSCLC who received either 8 or 10 mg/kg i.v. on days 1 and 8 of 21-day cycles. The primary endpoints were safety and objective response rate (ORR); duration of response, progression-free survival (PFS), and overall survival (OS) were secondary endpoints.Results: Sixty percent of patients showed tumor shrinkage from baseline CTs. On an intention-to-treat basis (N = 50), the ORR was 14% (17% for the 10-mg/kg group); the median response duration, 5.7 months; the clinical benefit rate (CBR ≥4 months), 34%; median PFS, 3.7 months; and median OS, 7.5 months. There was a suggested improvement in PR, CBR, and PFS with sacituzumab govitecan in second-line patients who were sensitive to first-line therapy, but no difference between first-line chemosensitive versus chemoresistant patients in the overall population. There was a statistically significant higher OS in those patients who received prior topotecan versus no topotecan therapy in a small subgroup. Grade ≥3 adverse events included neutropenia (34%), fatigue (13%), diarrhea (9%), and anemia (6%). Trop-2 tumor staining was not required for patient selection. No antibodies to the drug conjugate or its components were detected on serial blood collections.Conclusions: Sacituzumab govitecan appears to have a safe and effective therapeutic profile in heavily pretreated mSCLC patients, including those who are chemosensitive or chemoresistant to first-line chemotherapy. Additional studies as a monotherapy or combination therapy are warranted. Clin Cancer Res; 23(19); 5711-9. ©2017 AACR.

Therapy of Advanced Non-Small-Cell Lung Cancer With an SN-38-Anti-Trop-2 Drug Conjugate, Sacituzumab Govitecan.

Purpose Trop-2, expressed in most solid cancers, may be a target for antibody-drug conjugates (ADCs) in non-small-cell lung cancer (NSCLC). We studied sacituzumab govitecan (IMMU-132), a Trop-2 ADC, for the targeting of SN-38. Patients and Methods We evaluated IMMU-132 in a single-arm multicenter trial in patients with pretreated metastatic NSCLC who received either 8 or 10 mg/kg on days 1 and 8 of 21-day cycles. The primary end points were safety and objective response rate (ORR). Progression-free survival and overall survival were secondary end points. Results Fifty-four patients were treated. In the response-assessable study population (n = 47), which had a median of three prior therapies (range, two to seven), the ORR was 19%; median response duration, 6.0 months (95% CI, 4.8 to 8.3 months); and clinical benefit rate (complete response + partial response + stable disease ≥ 4 months), 43%. ORR in the intention-to-treat (ITT) population was 17% (nine of 54). Responses occurred with a median onset of 3.8 months, including patients who had relapsed or progressed after immune checkpoint inhibitor therapy. Median ITT progression-free survival was 5.2 months (95% CI, 3.2 to 7.1 months) and median ITT overall survival, 9.5 months (95% CI, 5.9 to 16.7 months). Grade 3 or higher adverse events included neutropenia (28%), diarrhea (7%), nausea (7%), fatigue (6%), and febrile neutropenia (4%). One patient developed a transient immune response, despite patients receiving a median of 10 doses. More than 90% of 26 assessable archival tumor specimens were highly positive (2+, 3+) for Trop-2 by immunohistochemistry, which suggests that Trop-2 is not a predictive biomarker for response. Conclusion IMMU-132 was well-tolerated and induced durable responses in heavily pretreated patients with metastatic NSCLC. This ADC should be studied further in this disease and in other patients with Trop-2-expressing tumors.

Sacituzumab govitecan (IMMU-132), an anti-Trop-2-SN-38 antibody-drug conjugate for the treatment of diverse epithelial cancers: Safety and pharmacokinetics.

BACKGROUND: Sacituzumab govitecan (IMMU-132), an antitrophoblastic cell-surface antigen (anti-Trop-2) humanized antibody-SN-38 conjugate, had encouraging efficacy in the phase 1 clinical trial. This report further examines the pharmacokinetics and safety of multiple cycles of IMMU-132 at doses of 8 or 10 mg/kg in patients with diverse advanced epithelial cancers. METHODS: Patients who had multiple prior therapies received IMMU-132 on days 1 and 8 of 21-day treatment cycles. Trop-2 staining of archived tumor specimens, clearance of IMMU-132 and its constituents (ie, immunoglobulin G [IgG], SN-38 [a camptothecin, the active component of irinotecan], and glucuronidated SN-38 [SN-38G]), antibody responses, and uridine diphosphate glucuronosyltransferase 1A1 (UGT1A1) levels were determined. Safety was assessed according to Common Terminology Criteria for Adverse Events version 4.0, and responses were assessed using Response Evaluation Criteria in Solid Tumors, version 1.1. RESULTS: Patients with diverse metastatic cancers who received IMMU-132 at 8 mg/kg (n = 81) and 10 mg/kg (n = 97) were examined. Trop-2 was positive in 93% of the available specimens. IMMU-132 cleared with a half-life of approximately 11 to 14 hours, reflecting the release of SN-38 from the conjugate; IgG cleared more slowly (half-life, approximately 103-114 hours). Most SN-38 in the serum (>95%) was bound to IgG. SN-38G concentrations were lower than SN-38 concentrations. Dose-limiting neutropenia after the first cycle was not correlated with SN-38 in serum or with UGT1A1 genotype. No antibody responses were detected. Objective responses were observed in several indications, including metastatic triple-negative breast cancer, confirming that 10 mg/kg produced an encouraging overall response. CONCLUSIONS: Sacituzumab govitecan has a predictable pharmacokinetic profile and manageable toxicity at doses of 8 and 10 mg/kg. With objective responses and a good therapeutic index at 10 mg/kg, this dose was chosen for future development. Cancer 2017;123:3843-3854. © 2017 American Cancer Society.

Efficacy and Safety of Anti-Trop-2 Antibody Drug Conjugate Sacituzumab Govitecan (IMMU-132) in Heavily Pretreated Patients With Metastatic Triple-Negative Breast Cancer.

Purpose Trop-2, expressed in most triple-negative breast cancers (TNBCs), may be a potential target for antibody-drug conjugates. Sacituzumab govitecan, an antibody-drug conjugate, targets Trop-2 for the selective delivery of SN-38, the active metabolite of irinotecan. Patients and Methods We evaluated sacituzumab govitecan in a single-arm, multicenter trial in patients with relapsed/refractory metastatic TNBC who received a 10 mg/kg starting dose on days 1 and 8 of 21-day repeated cycles. The primary end points were safety and objective response rate; secondary end points were progression-free survival and overall survival. Results In 69 patients who received a median of five prior therapies (range, one to 12) since diagnosis, the confirmed objective response rate was 30% (partial response, n = 19; complete response, n = 2), the median response duration was 8.9 (95% CI, 6.1 to 11.3) months, and the clinical benefit rate (complete response + partial response + stable disease ≥ 6 months) was 46%. These responses occurred early, with a median onset of 1.9 months. Median progression-free survival was 6.0 (95% CI, 5.0 to 7.3) months, and median overall survival was 16.6 (95% CI, 11.1 to 20.6) months. Grade ≥ 3 adverse events included neutropenia (39%), leukopenia (16%), anemia (14%), and diarrhea (13%); the incidence of febrile neutropenia was 7%. The majority of archival tumor specimens (88%) were moderately to strongly positive for Trop-2 by immunohistochemistry. No neutralizing antibodies to the ADC or antibody were detected, despite repeated cycles developed. Conclusion Sacituzumab govitecan was well tolerated and induced early and durable responses in heavily pretreated patients with metastatic TNBC. As a therapeutic target and predictive biomarker, Trop-2 warrants further research.

(90)Y-clivatuzumab tetraxetan with or without low-dose gemcitabine: A phase Ib study in patients with metastatic pancreatic cancer after two or more prior therapies.

BACKGROUND: For patients with metastatic pancreatic adenocarcinoma, there are no approved or established treatments beyond the 2nd line. A Phase Ib study of fractionated radioimmunotherapy was undertaken in this setting, administering (90)Y-clivatuzumab tetraxetan (yttrium-90-radiolabelled humanised antibody targeting pancreatic adenocarcinoma mucin) with or without low radiosensitising doses of gemcitabine. METHODS: Fifty-eight patients with three (2-7) median prior treatments were treated on Arm A (N=29, (90)Y-clivatuzumab tetraxetan, weekly 6.5 mCi/m(2)doses×3, plus gemcitabine, weekly 200 mg/m(2) doses×4 starting 1 week earlier) or Arm B (N=29, (90)Y-clivatuzumab tetraxetan alone, weekly 6.5 mCi/m(2)doses×3), repeating cycles after 4-week delays. Safety was the primary endpoint; efficacy was also evaluated. RESULTS: Cytopaenias (predominantly transient thrombocytopenia) were the only significant toxicities. Fifty-three patients (27 Arm A, 26 Arm B, 91% overall) completed ⩾1 full treatment cycles, with 23 (12 Arm A, 11 Arm B; 40%) receiving multiple cycles, including seven (6 Arm A, 1 Arm B; 12%) given 3-9 cycles. Two patients in Arm A had partial responses by RECIST criteria. Kaplan-Meier overall survival (OS) appeared improved in Arm A versus B (hazard ratio [HR] 0.55, 95% CI: 0.29-0.86; P=0.017, log-rank) and the median OS for Arm A versus Arm B increased to 7.9 versus 3.4 months with multiple cycles (HR 0.32, P=0.004), including three patients in Arm A surviving >1 year. CONCLUSIONS: Clinical studies of (90)Y-clivatuzumab tetraxetan combined with low-dose gemcitabine appear feasible in metastatic pancreatic cancer patients beyond 2nd line and a Phase III trial of this combination is now underway in this setting.

First-in-Human Trial of a Novel Anti-Trop-2 Antibody-SN-38 Conjugate, Sacituzumab Govitecan, for the Treatment of Diverse Metastatic Solid Tumors.

PURPOSE: Sacituzumab govitecan (IMMU-132) is an antibody-drug conjugate (ADC) targeting Trop-2, a surface glycoprotein expressed on many epithelial tumors, for delivery of SN-38, the active metabolite of irinotecan. This phase I trial evaluated this ADC as a potential therapeutic for pretreated patients with a variety of metastatic solid cancers. EXPERIMENTAL DESIGN: Sacituzumab govitecan was administered on days 1 and 8 of 21-day cycles, with cycles repeated until dose-limiting toxicity or progression. Dose escalation followed a standard 3 + 3 scheme with 4 planned dose levels and dose delay or reduction allowed. RESULTS: Twenty-five patients (52-60 years old, 3 median prior chemotherapy regimens) were treated at dose levels of 8 (n = 7), 10 (n = 6), 12 (n = 9), and 18 (n = 3) mg/kg. Neutropenia was dose limiting, with 12 mg/kg the maximum tolerated dose for cycle 1, but too toxic with repeated cycles. Lower doses were acceptable for extended treatment with no treatment-related grade 4 toxicities and grade 3 toxicities limited to fatigue (n = 3), neutropenia (n = 2), diarrhea (n = 1), and leukopenia (n = 1). Using CT-based RECIST 1.1, two patients achieved partial responses (triple-negative breast cancer, colon cancer) and 16 others had stable disease as best response. Twelve patients maintained disease control with continued treatment for 16 to 36 weeks; 6 survived 15 to 20+ months. No preselection of patients based on tumor Trop-2 expression was done. CONCLUSIONS: Sacituzumab govitecan had acceptable toxicity and encouraging therapeutic activity in patients with difficult-to-treat cancers. The 8 and 10 mg/kg doses were selected for phase II studies.

A Phase I/II Trial of BNC105P with Everolimus in Metastatic Renal Cell Carcinoma.

PURPOSE: BNC105P inhibits tubulin polymerization, and preclinical studies suggest possible synergy with everolimus. In this phase I/II study, efficacy and safety of the combination were explored in patients with metastatic renal cell carcinoma (mRCC). EXPERIMENTAL DESIGN: A phase I study in patients with clear cell mRCC and any prior number of therapies was conducted using a classical 3 + 3 design to evaluate standard doses of everolimus with increasing doses of BNC105P. At the recommended phase II dose (RP2D), patients with clear cell mRCC and one to two prior therapies (including ≥ 1 VEGF-TKI) were randomized to BNC105P with everolimus (arm A) or everolimus alone (arm B). The primary endpoint of the study was 6-month progression-free survival (6MPFS). Secondary endpoints included response rate, PFS, overall survival, and exploratory biomarker analyses. RESULTS: In the phase I study (N = 15), a dose of BNC105P at 16 mg/m(2) with everolimus at 10 mg daily was identified as the RP2D. In the phase II study, 139 patients were randomized, with 69 and 67 evaluable patients in arms A and B, respectively. 6MPFS was similar in the treatment arms (arm A: 33.82% vs. arm B: 30.30%, P = 0.66) and no difference in median PFS was observed (arm A: 4.7 mos vs. arm B: 4.1 mos; P = 0.49). Changes in matrix metalloproteinase-9, stem cell factor, sex hormone-binding globulin, and serum amyloid A protein were associated with clinical outcome with BNC105P. CONCLUSIONS: Although the primary endpoint was not met in an unselected population, correlative studies suggest several biomarkers that warrant further prospective evaluation.

Phase I study of capecitabine, oxaliplatin, bevacizumab, and everolimus in advanced solid tumors.

PURPOSE: To define maximum tolerated dose (MTD), toxicities, and pharmacodynamics of capecitabine, oxaliplatin, bevacizumab, and everolimus in advanced solid tumor patients. DESIGN: This was a standard "3 + 3" dose-escalation trial. All subjects received bevacizumab 7.5 mg/kg on day 1 of each cycle. Doses for capecitabine, oxaliplatin and everolimus were modified per dose limiting toxicity (DLT). Baseline and on-treatment plasma biomarkers were analyzed. Archived tumor mRNA levels were evaluated for NRP1, NRP2 and VEGF-A isoforms. RESULTS: Twenty-nine patients were evaluable for toxicity and 30 for efficacy. Two DLTs were observed in cohort 1 and one DLT each was observed in cohort -1 and -1b. Grade ≥3 toxicities included neutropenia, hypertension, perforation/fistula/hemorrhage, hypertriglyceridemia, diarrhea, and thromboembolism. Twelve subjects experienced partial response (PR); 12 had stable disease as best response. Three of seven chemorefractory metastatic colorectal cancer (mCRC) subjects experienced PR; 8 of 15 chemonaive mCRC subjects experienced PR. Plasma TßRIII and IL-6 increased on treatment but without correlation to outcome. Increased VEGF165 levels significantly correlated with longer progression free survival. CONCLUSIONS: Everolimus with full dose capecitabine, oxaliplatin, and bevacizumab had unacceptable toxicity. MTD was: everolimus 5 mg daily; capecitabine 680 mg/m(2) BID days 1-14; oxaliplatin 100 mg/m(2) and bevacizumab 7.5 mg/kg, day 1. Activity was noted in mCRC.

Phase I study of dasatinib in combination with capecitabine, oxaliplatin and bevacizumab followed by an expanded cohort in previously untreated metastatic colorectal cancer.

PURPOSE: Dasatinib inhibits src family kinases and has anti-angiogenic properties. We conducted a phase I study of dasatinib, capecitabine, oxaliplatin, and bevacizumab (CapeOx/bevacizumab), with an expansion cohort in metastatic colorectal cancer (CRC). METHODS: Patients were enrolled in a dose escalation cohort to establish the maximum tolerated dose (MTD) and the recommended phase II dose (RP2D). Using a "3 + 3" design, twelve patients with advanced solid tumors received dasatinib (50 mg twice daily or 70 mg daily), capecitabine (850 mg/m(2) twice daily, days 1-14), oxaliplatin (130 mg/m(2) on day 1) and bevacizumab (7.5 mg/kg on day1), every 3 weeks. Ten patients with previously untreated metastatic CRC were then enrolled in an expansion cohort. Activated src (src(act)) expression was measured by immunohistochemistry, using an antibody that selectively recognizes the active conformation of src (clone 28). RESULTS: Twenty-two patients were enrolled between June 2009 and May 2011. Two DLTs were observed in the 50 mg bid dasatinib cohort, and one DLT was observed in the 70 mg daily dasatinib cohort. The MTD and RP2D for dasatinib was 70 mg daily. The most common treatment-related adverse events were fatigue (20; 91 %) and diarrhea (18; 82 %). Biomarker analysis of src(act) expression demonstrated that the overall response rate (ORR) was 75 % (6/8) for patients with high src(act) expression (IHC ≥ 2), compared to 0 % (0/8) for patients with low srcact expression (IHC 0 or 1); (p = 0.007). CONCLUSIONS: The RP2D of dasatinib is 70 mg daily in combination with CapeOx/bevacizumab. High levels of srcact expression may predict those patients most likely to benefit from dasatinib.

Phase I study of bevacizumab, everolimus, and panobinostat (LBH-589) in advanced solid tumors.

PURPOSE: To define the maximum tolerated dose, clinical toxicities, and pharmacodynamics of bevacizumab, everolimus, and panobinostat (LBH-589) when administered in combination to patients with advanced solid tumor malignancies. EXPERIMENT DESIGN: Subjects received 10 mg of panobinostat three times weekly, 5 or 10 mg everolimus daily, and bevacizumab at 10 mg/kg every 2 weeks. Dose-limiting toxicities (DLTs) were assessed in cycle 1; toxicity evaluation was closely monitored throughout treatment. Treatment continued until disease progression or undesirable toxicity. Protein acetylation was assessed in peripheral blood mononuclear cells (PBMC) both at baseline and on treatment. RESULTS: Twelve subjects were evaluable for toxicity and nine subjects for response. DLTs in cohort 1 included grade 2 esophagitis and grade 3 oral mucositis; DLTs in cohort -1 were grade 2 ventricular arrhythmia and grade 2 intolerable skin rash. Common adverse events were diarrhea (50 %), headache (33 %), mucositis/stomatitis (25 %), hyperlipidemia (25 %), and thrombocytopenia (25 %). There was 1 partial response; an additional 2 subjects had stable disease as best response. No consistent changes in protein acetylation in PBMC were observed in samples available from eight patients on treatment compared with baseline. CONCLUSIONS: Bevacizumab, everolimus, and panobinostat in combination at the lowest proposed doses did not have an acceptable safety and tolerability profile and did not consistently inhibit HDAC activity; therefore, we do not recommend further evaluation.

A phase I study of bevacizumab, everolimus and panitumumab in advanced solid tumors.

PURPOSE: Preclinical data suggest concurrent inhibition of VEGF, mTOR and EGFR pathways may augment antitumor and antiangiogenic effects compared to inhibition of each pathway alone. This study evaluated the maximum tolerated dose/recommended phase II dose and safety and tolerability of bevacizumab, everolimus and panitumumab drug combination. METHODS: Subjects with advanced solid tumors received escalating doses of everolimus and flat dosing of panitumumab at 4.8 mg/kg and bevacizumab at 10 mg/kg every 2 weeks. Dose-limiting toxicities (DLTs) were assessed in cycle 1; toxicity evaluation was closely monitored throughout treatment. Treatment continued until disease progression or undesirable toxicity. RESULTS: Thirty-two subjects were evaluable for toxicity; 31 subjects were evaluable for tumor response. DLTs were observed in cohorts with everolimus at 10 and 5 mg daily and included grade 3 mucositis, skin rash and thrombocytopenia. Therefore, everolimus was dose-reduced to 5 mg three times weekly, which improved the tolerability of the treatment regimen. Common adverse events were skin rash/pruritus (91 %), mucositis/stomatitis (75 %), hypomagnesemia (72 %), hypocalcemia (56 %) and hypokalemia (50 %). There were 3 partial responses; an additional 10 subjects had stable disease ≥6 months. Three subjects with ovarian cancer and one with endometrial cancer achieved prolonged disease control ranging from 11 to >40 months. CONCLUSIONS: The recommended phase II dose is everolimus at 5 mg three times weekly plus panitumumab at 4.8 mg/kg and bevacizumab at 10 mg/kg every 2 weeks. This dosing regimen has an acceptable safety and tolerability profile and appears to have moderate the clinical activity in refractory tumors.