Safety, Tolerability, and Pharmacokinetics of TAK-931, a Cell Division Cycle 7 Inhibitor, in Patients with Advanced Solid Tumors: A Phase I First-in-Human Study

Purpose:

We conducted a first-in-human, dose-escalation study, to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and activity of TAK-931, a cell division cycle 7 inhibitor, in Japanese patients with advanced solid tumors.

Experimental Design:

Patients ages ≥20 years received oral TAK-931: once daily for 14 days in 21-day cycles (schedule A; from 30 mg); once daily or twice daily for 7 days on, 7 days off in 28-day cycles (schedule B; from 60 mg); continuous once daily (schedule D; from 20 mg); or once daily for 2 days on, 5 days off (schedule E; from 100 mg) in 21-day cycles.

Results:

Of the 80 patients enrolled, all had prior systemic treatment and 86% had stage IV disease. In schedule A, 2 patients experienced dose-limiting toxicities (DLTs) of grade 4 neutropenia and the maximum tolerated dose (MTD) was 50 mg. In schedule B, 4 patients experienced DLTs of grade 3 febrile neutropenia (n = 3) or grade 4 neutropenia (n = 1); the MTD was 100 mg. Schedules D and E were discontinued before MTD determination. The most common adverse events were nausea (60%) and neutropenia (56%). Time to maximum plasma concentration of TAK-931 was approximately 1–4 hours postdose; systemic exposure was approximately dose proportional. Posttreatment pharmacodynamic effects correlating to drug exposure were observed. Overall, 5 patients achieved a partial response.

Conclusions:

TAK-931 was tolerable with a manageable safety profile. TAK-931 50 mg once daily days 1–14 in 21-day cycles was selected as a recommended phase II dose and achieved proof of mechanism.

Trial registration ID:

NCT02699749

Significance:

This was the first-in-human study of the CDC7 inhibitor, TAK-931, in patients with solid tumors. TAK-931 was generally tolerable with a manageable safety profile. The recommend phase II dose was determined to be TAK-931 50 mg administered once daily on days 1–14 of each 21-day cycle. A phase II study is ongoing to confirm the safety, tolerability, and antitumor activity of TAK-931 in patients with metastatic solid tumors.

Phase 1/2a trial of nadunolimab, a first-in-class fully humanized monoclonal antibody against IL1RAP, in combination with gemcitabine and nab-paclitaxel (GN) in patients with pancreatic adenocarcinoma (PDAC)

4141

Background: Interleukin-1 Receptor Accessory Protein (IL1RAP) is expressed on cancer and stromal cells in PDAC. The IL-1 pathway is active in the pancreatic tumor microenvironment and upregulated in response to chemotherapy. IL1RAP interacts with IL-1R1 and modulates downstream factors (e.g. IL-6, IL-8) and CRP level. Nadunolimab (CAN04), a fully humanized ADCC-enhanced IgG1 antibody, targets IL1RAP and blocks IL-1α and IL-1β signaling. Here, results are reported from the phase 1/2a clinical trial CANFOUR evaluating nadunolimab combined with GN in PDAC. Methods: Patients (pts) with previously untreated, unresectable, locally advanced or metastatic PDAC received nadunolimab at 1 (n=20) 2.5 (n=20), 5 (n=28) or 7.5 mg/kg (n=8) Q2W with standard GN. Primary objective was safety; secondary objectives included ORR, iPFS per iRECIST and OS, and exploratory objectives included effects on serum and tumor tissue biomarkers. Results: In total, 76 pts were enrolled: median age 63 years (43-89), 42% female, 93% stage IV, 45% PS=0, 9% received adjuvant chemotherapy. Treatment-related adverse events (AE) of grade≥3 were reported in 72% with neutropenia being most frequent. G-CSF prophylaxis was useful in managing neutropenic events. The 7.5 mg/kg dose was above MTD due to neutropenia. Infusion-related reactions were reported in 29% (grade 3 in 3%). Peripheral sensory neuropathy was rare (only two grade 2 events). Common treatment-related grade 3/4 AE are shown below. Seventy-three pts received combination therapy and were included in the efficacy analysis. Three pts did not receive chemotherapy due to consent withdrawal (n=2) or clinical deterioration (n=1). Median iPFS was 7.3 months (95% CI 5.6-8.9) with 15 pts still on treatment, median OS was 13.2 months (10.0-19.1) with 62% of pts alive and 1-year survival of 59% (42-72%). ORR was 33% (22-45), disease control rate 63% (51-74%) and duration of response 5.7 months (3.9-11.1). ORR was similar for all dose levels. Low baseline CRP was favorable for OS; reduction of serum IL-8 and CRP during Cycle 1 correlated with positive impact on OS. Also, neutrophil-lymphocyte ratio was reduced throughout the trial, driven by the reduction in circulating neutrophils. IL1RAP expression on cancer and stromal cells was confirmed in tumor biopsies. Conclusions: Nadunolimab combined with GN shows promising iPFS and OS and manageable safety in PDAC pts. A phase 2/3 trial of nadunolimab combined with chemotherapy in PDAC is planned and nadunolimab is also currently evaluated in additional combination trials with chemotherapy or IO. Clinical trial information: NCT03267316. [Table: see text]

Phase 1/2a trial of nadunolimab, a first-in-class fully humanized monoclonal antibody against IL1RAP, in combination with cisplatin and gemcitabine (CG) in patients with non-small cell lung cancer (NSCLC)

9020

Background: Interleukin-1 Receptor Accessory Protein (IL1RAP) is expressed by cancer and stromal cells of many solid tumors. The IL-1 pathway is active in tumors and upregulated in response to chemotherapy. IL1RAP interacts with IL-1R1 and modulates downstream factors (e.g. IL-6, IL-8) and CRP level. Nadunolimab (CAN04), a fully humanized ADCC-enhanced IgG1 antibody, targets IL1RAP and blocks IL-1α and IL-1β signaling. Here, results are reported from the phase 1/2a clinical trial CANFOUR evaluating nadunolimab combined with CG in NSCLC. Methods: Patients (pts) with unresectable, locally advanced or metastatic NSCLC, progressed on pembrolizumab or in first line for advanced disease, were eligible. Pts received 1 (n =17), 2.5 (n = 3) or 5 mg/kg (= 13) nadunolimab given Q1W in Cycle 1 and Q2W from Cycle 2, combined with standard CG. Due to risk of infusion-related reactions, a priming dose of 0.5 mg/kg nadunolimab was given one week before CG. Primary objective was safety; secondary objectives included ORR, PFS and OS, and exploratory objectives included effects on serum and tumor tissue biomarkers. Results: Thirty-three pts were enrolled: median age 64 years (39-77), 30% female, 42% ECOG 0, 55% non-squamous histology, 82% stage IV, 45% received previous pembrolizumab monotherapy. Treatment-related adverse events of grade≥3 were observed in 73% of pts, including neutropenia (58%), febrile neutropenia (9%), thrombocytopenia (30%) and anemia (18%). Neutropenia could be managed by G-CSF. Thirty pts received combination therapy and were included in the efficacy analysis. Three pts did not receive chemotherapy due to clinical deterioration (n = 2) or consent withdrawal (n = 1). ORR was 53% (95% CI 34-72%), disease control rate 80% (61-92%) and median duration of response 5.5 months (3.7-7.0) with 23% of pts still on treatment. The lower limit of the 95% CI for the observed ORR excludes the pre-specified 30%. ORR in pts with squamous histology was 46% and non-squamous 56%. Median PFS was 6.7 months (5.5-7.3) and median OS 13.7 months. The neutrophil-lymphocyte ratio was reduced throughout the trial and was driven by the reduction in circulating neutrophil numbers. IL1RAP expression on both cancer and stromal cells was confirmed in tumor biopsies. Conclusions: Nadunolimab combined with CG shows manageable safety and promising efficacy with a response rate of 53% in NSCLC pts. Nadunolimab is currently evaluated in several clinical trials investigating chemotherapy or IO combinations, including carboplatin and pemetrexed in non-squamous NSCLC. Clinical trial information: NCT03267316.

Safety, tolerability, and preliminary efficacy of nadunolimab, a first-in-class monoclonal antibody against IL1RAP, in combination with pembrolizumab in subjects with solid tumors

2527

Background: Interleukin-1 Receptor Accessory Protein (IL1RAP) is expressed on cancer and stromal cells of many solid tumors. IL1RAP interacts with IL-1R1, modulating downstream factors (e.g. IL-6, IL-8) and CRP level. Nadunolimab (CAN04), a fully humanized ADCC-enhanced IgG1 antibody, targets IL1RAP and blocks IL-1α and IL-1β. IL-1 promotes an immune suppressive microenvironment, e.g. by recruitment of MDSC which may induce checkpoint inhibitor resistance. Here, initial data are reported from the phase Ib clinical trial CIRIFOUR, evaluating nadunolimab combined with pembrolizumab in solid tumor patients (pts) progressed on prior anti-PD-(L)1 therapy. Methods: Primary objective was evaluating safety and tolerability of nadunolimab combined with pembrolizumab in pts with metastatic NSCLC (n = 5), head and neck squamous cancer (n = 9) or malignant melanoma (n = 1), progressed on prior anti-PD-(L)1 therapy of ≥12 weeks (wks). Dosing started with a priming dose of 0.5 mg/kg nadunolimab on Day -7, followed by 5 mg/kg nadunolimab weekly combined with standard pembrolizumab dosing. A safety lead-in phase 3+3 design was employed. Secondary objectives included preliminary efficacy and responses based on RECIST/iRECIST. Serum biomarkers and tumor biopsies were also analyzed. Results: Fifteen pts received at least one dose of 5 mg/kg nadunolimab with pembrolizumab: median age 63 years (50-79), 27% female, 100% Stage IV, 93% and 7% received prior pembrolizumab or nivolumab respectively, 7% ECOG 0, 93% ECOG 1. The pts had received a mean of 2.3 (range 1-6) previous lines of treatment. SAE were reported in 47% with one considered treatment-related (febrile neutropenia). Two treatment-related grade 3 AE were reported: one febrile neutropenia (DLT), one pneumonitis. No pts discontinued treatment due to treatment-related AE. One patient (7%) had unconfirmed PR as best response, 8 (53%) showed SD, and 6 (40%) iUPD. At time of analysis, 5 pts (33%) received ongoing treatment. Of these, two pts had received therapy for over 31 wks, another two for over 49 wks. Decreased IL-6 was observed after four wks and persisted during treatment. Reduced neutrophil-lymphocyte ratio (NLR) was observed throughout the study, appeared after first treatment, and was driven by a moderate reduction in circulating neutrophils. Decreased IL-6 and NLR were most pronounced in pts with longest disease control duration. IL1RAP expression on cancer and stromal cells was confirmed in tumor biopsies. Conclusions: The nadunolimab and pembrolizumab combination was considered safe and tolerable with preliminary evidence of prolonged disease control. The favorable safety provides basis for evaluation of further therapy with this combination. Next, nadunolimab and pembrolizumab will be assessed with carboplatin/pemetrexed in non-squamous NSCLC. Clinical trial information: NCT04452214.

Safety, tolerability and preliminary efficacy of CAN04, a first in class monoclonal antibody against IL1RAP, in combination with nab-paclitaxel and gemcitabine (NG) in subjects with pancreatic cancer

e16228

Background: Interleukin-1 Receptor Accessory Protein (IL1RAP) is expressed on cancer and stromal cells in many solid tumors. CAN04 is a fully humanized IgG1 targeting IL1RAP blocking IL-1α and β signaling and triggering ADCC. As monotherapy, CAN04 has been administered without reaching MTD up to 15mg/kg. We report initial data from CAN04 in combination with NG in pts with pancreatic cancer (PDAC). Methods: Primary objective was to determine safety and tolerability of CAN04 in combination with standard NG as first line treatment in pts with locally advanced/metastatic PDAC. Secondary objectives included establishing preliminary efficacy. Tumor responses were evaluated according to RECIST/iRECIST. Results: 36 patients (pts) received at least 1 dose of CAN04: median age 62 yrs (46-87), 47% women, 94% stage IV, 8% had received prior adjuvant therapy; 59% ECOG 0, 41% ECOG 1. Dosing was initiated at 5mg/kg, escalated to 7.5mg/kg (n = 8) which was considered above MTD due to hematological toxicity, followed by expansion at 5mg/kg. Infusion related reactions (IRRs) were seen primarily with CAN04 priming dose of 0.5 mg/kg (25% G1, 25% G2, 3% G3). G3 or higher AEs (all/related) were dominated by hematological toxicity and reported in 89%/72% of pts (see table). SAEs were reported in 67% pts (44% G3/G4), in 33% considered related (19% G3/G4). 33% of pts discontinued due to AEs: 4 deterioration of general condition, 2 IRR, 2 bilirubin elevation, 1 bile duct obstruction, 1 hemolytic uremic syndrome, 1 pancreatitis, 1 asthenia, 1 decreased appetite, 1 pneumonitis. There were 3 on treatment deaths: disease progression, gastrointestinal obstruction and cholangitis. For the mITT efficacy analysis (n = 31), 5 pts were excluded: 3 discontinued before receiving NG (2 consent withdrawals after IRRs, tumor related physical deterioration) and 2 did not complete Cycle 1 due to cholangitis and GI obstruction respectively. 12 pts (39%) had confirmed or unconfirmed PR as best response, 8 (26%) more showed SD and 9 (29%) had PD. Six pts underwent PD confirmation: 3 pts had prolonged immune unconfirmed PD (iUPD) by iRECIST and > 50% decreases in CA19-9 and were on treatment for 4.5 (ongoing), 6 and 8 months, respectively. Clinical benefit rate (PR+SD+prolonged iUPD): 74%. At the time of this analysis, 12 pts (38%) are ongoing. Median duration of response is currently 7.5 months (1.8-13.8 months). Conclusions: The clinical benefit rate of CAN04 in combination with NG is encouraging (74%). The G3/G4 neutropenia and febrile neutropenia rate is higher than expected for NG alone. Expansion cohorts at lower CAN04 doses have been initiated. Clinical trial information: NCT03267316. [Table: see text]

Gastrointestinal complications in patients treated with ipilimumab and nivolumab combination therapy or monotherapy

Aim & methods: A retrospective study using the IBM Explorys Universe Database assessed the risk of gastrointestinal events (enterocolitis or diarrhea) among melanoma and lung cancer patients treated with ipilimumab and nivolumab combination or monotherapy. Results & conclusion: There were 904 melanoma patients (607 ipilimumab, 140 nivolumab and 157 combo) and 1641 lung cancer patients (68 ipilimumab, 1542 nivolumab and 31 combo). Approximately, 37% of lung patients and 46% of melanoma patients experienced at least one adverse event. After adjusting for covariates, patients receiving combination therapy were more likely to have a gastrointestinal event compared with ipilimumab monotherapy patients (melanoma hazard ratio: 1.54; 95% CI: 1.06-2.25; lung hazard ratio: 2.93; 95% CI: 1.09-7.89).

Gastrointestinal adverse events with combination of checkpoint inhibitors in advanced melanoma: a systematic review

INTRODUCTION

Immunotherapies, including checkpoint inhibitors (CIs) such as cytotoxic T-lymphocyte antigen-4 (CTLA-4) and programmed death-1 (PD-1) inhibitors, are revolutionizing the treatment of advanced melanoma. Combining CTLA-4 and PD-1 inhibitors provides additional clinical benefit compared with single agents alone. However, combination therapy can increase the incidence of gastrointestinal adverse events (GI AEs). This systematic review assessed the epidemiological, clinical, economic, and humanistic burden of GI AEs due to combination CIs in advanced melanoma.

METHODS

MEDLINE, EMBASE, and the Cochrane Library were systematically searched (December 2011 to December 2016) to identify primary studies, systematic reviews, meta-analyses, and conference proceedings (2014-2016) evaluating adults treated with ≥2 CIs for advanced melanoma.

RESULTS

Of the 3391 identified articles, 14 were included. Most studies examined the ipilimumab plus nivolumab combination. Any grade and grade 3-4 GI AEs occurred in more patients receiving ipilimumab plus nivolumab versus ipilimumab or nivolumab alone. The most common grade 3-4 GI AEs were diarrhea and colitis. Grade 3-4 colitis occurred in more patients receiving ipilimumab plus nivolumab. However, grade 3-4 diarrhea occurred at the same rate as ipilimumab alone. GI AEs developed with ipilimumab plus nivolumab approximately 6.6 weeks after initiating treatment. No studies assessing the economic or humanistic burden of GI AEs were identified.

CONCLUSION

GI AEs occurred at a higher rate and greater severity in patients treated with ipilimumab plus nivolumab versus ipilimumab or nivolumab monotherapy. The lack of research on economic and humanistic burden of GI AEs with combination CIs for advanced melanoma represents an unmet need in the literature and should be explored in future studies.

Phase III study of iniparib plus gemcitabine and carboplatin versus gemcitabine and carboplatin in patients with metastatic triple-negative breast cancer

PURPOSE

There is a lack of treatments providing survival benefit for patients with metastatic triple-negative breast cancer (mTNBC), with no standard of care. A randomized phase II trial showed significant benefit for gemcitabine, carboplatin, and iniparib (GCI) over gemcitabine and carboplatin (GC) in clinical benefit rate, response rate, progression-free survival (PFS), and overall survival (OS). Here, we formally compare the efficacy of these regimens in a phase III trial.

PATIENTS AND METHODS

Patients with stage IV/locally recurrent TNBC who had received no more than two previous chemotherapy regimens for mTNBC were randomly allocated to gemcitabine 1,000 mg/m(2) and carboplatin area under the curve 2 (days 1 and 8) alone or GC plus iniparib 5.6 mg/kg (days 1, 4, 8, and 11) every 3 weeks. Random assignment was stratified by the number of prior chemotherapies. The coprimary end points were OS and PFS. Patients receiving GC could cross over to iniparib on progression.

RESULTS

Five hundred nineteen patients were randomly assigned (261 GCI; 258 GC). In the primary analysis, no statistically significant difference was observed for OS (hazard ratio [HR] = 0.88; 95% CI, 0.69 to 1.12; P = .28) nor PFS (HR = 0.79; 95% CI, 0.65 to 0.98; P = .027). An exploratory analysis showed that patients in the second-/third-line had improved OS (HR = 0.65; 95% CI, 0.46 to 0.91) and PFS (HR = 0.68; 95% CI, 0.50 to 0.92) with GCI. The safety profile for GCI was similar to GC.

CONCLUSION

The trial did not meet the prespecified criteria for the coprimary end points of PFS and OS in the ITT population. The potential benefit with iniparib observed in second-/third-line subgroup warrants further evaluation.

A phase II randomized study evaluating the addition of iniparib to gemcitabine plus cisplatin as first-line therapy for metastatic non-small-cell lung cancer

BACKGROUND

Iniparib is a novel anticancer agent initially considered a poly (ADP-ribose) polymerase (PARP) inhibitor, but subsequently shown to act via non-selective protein modification through cysteine adducts. This randomized phase II study investigated the addition of iniparib to gemcitabine-cisplatin in metastatic non-small-cell lung cancer (NSCLC) patients.

PATIENTS AND METHODS

Patients with histologically confirmed stage IV NSCLC were randomized 2 : 1 to receive gemcitabine (1250 mg/m(2), days 1/8) and cisplatin (75 mg/m(2), day 1) with [gemcitabine/cisplatin/iniparib (GCI)] or without [gemcitabine/cisplatin (GC)] iniparib (5.6 mg/kg, days 1/4/8/11) every 3 weeks for six cycles. The primary end point was the overall response rate (ORR). Secondary objectives included progression-free survival (PFS), overall survival (OS), and safety. The study was not designed for formal efficacy comparison, the control arm being to benchmark results against the literature.

RESULTS

One hundred and nineteen patients were randomized (39 GC and 80 GCI). More GCI patients were male (80% GCI and 67% GC) and had PS 0 (61% GCI and 49% GC). The ORR was 25.6% [95% confidence interval (CI) 13.0%-42.1%] with GC versus 20.0% (95% CI 11.9%-30.4%) with GCI, which did not allow rejection of the null hypothesis (ORR with GCI ≤20%; P = 0.545). Median PFS was 4.3 (95% CI 2.8-5.6) months with GC and 5.7 (95% CI 4.6-6.6) months with GCI (hazard ratio 0.89, 95% CI 0.56-1.40). Median OS was 8.5 (95% CI 5.5 to not reached) months with GC, and 12.0 (95% CI 8.9-17.1) months with GCI (hazard ratio 0.78, 95% CI 0.48-1.27). More GCI patients received second-line treatment (51% GC and 68% GCI). Toxicity was similar in the two arms. Grade 3-4 toxicities included asthenia (28% GC and 8% GCI), nausea (3% GC and 14% GCI), and decreased appetite (10% in each).

CONCLUSIONS

Addition of iniparib to GC did not improve ORR over GC alone. The GCI safety profile was comparable to GC alone. Imbalances in PS and gender distribution may have impacted study results regarding PFS and OS.

TRIAL REGISTRATION

ClinicalTrial.gov Identifier NCT01086254.

SOLTI NeoPARP: A phase II, randomized study of two schedules of iniparib plus paclitaxel and paclitaxel alone as neoadjuvant therapy in patients with triple-negative breast cancer (TNBC)

1011

Background: Iniparib is an anticancer agent with a mechanism of action still under investigation. A phase 2 randomized neoadjuvant study in patients (pts) with TNBC was designed to explore the activity and tolerability of two schedules of iniparib with weekly paclitaxel (PTX). Here we report the efficacy and safety results from a planned interim analysis (IA). Methods: The trial accrued a total of 141 pts in October 2011, of whom, 74 are included in this IA. All were chemo-naive, histologicallyconfirmed Stage II-IIIA TNBC (IIA 47%; IIB 35%; IIIA 16%) with a median age of 50 yr. Triple negative status was centrally confirmed [ER/PR <10%, HER2 IHC (0+, 1+) or FISH negative]. Pts were randomized (1:1:1) to receive weekly PTX (80 mg/m2, IV, d 1; N=25) alone or in combination with iniparib, either on a once weekly (QW) (11.2 mg/kg, IV, d 1; N=25) or twice weekly (BIW) (5.6 mg/kg, IV, d 1, 4; N=24) schedule. The total planned treatment duration was 12 wks. The IA endpoint is pathological complete response in the breast (pCR) as assessed by independent pathologists. Results: Two/2/3 pts in the PTX/QW/BIW arms, respectively, discontinued due to progressive disease per RECIST. Another 3/2/2 pts, respectively, discontinued due to investigator decision or an adverse event (AE). Thirteen pts presented with Grade 3/4 Treatment Emergent AE: 3 pts in PTX arm (1 neutropenia, 1 presyncope, 1 ALT elevation), 3 in QW arm (1 lymphopenia, 1 hyperkalemia, 1 pulmonary embolism), and 8 in the BIW arm (1 febrile neutropenia, 3 neutropenia, 1 aphonia, 1 syncope, 1 radius fracture and 1 vertigo). Laboratory Grade 3/4 neutropenia occurred in 4% of pts in PTX, 0% in QW and 21% of BIW arms, with 1/2/3 pts, respectively, requiring G-CSF usage. There were 4/7/6 pts in the PTX/QW/BIW arms with PTX dose modifications. Four pts (16%) in PTX arm, 4 pts (16%) in the QW arm and 6 pts (25%) in the BIW arm had confirmed pCR in the breast. Conclusions: In this IA population, the addition of iniparib regardless of the schedule to weekly PTX did not seem to add clinically significant toxicity. pCR rate in the breast is similar across treatment arms at this IA. NCT01204125.

Abstract A94: Dose determination of LY2603618, a Chk1 inhibitor, administered in combination with gemcitabine in patients with advanced cancer

Background: LY2603618 is a selective inhibitor of Chk1, a protein kinase that plays a key role in the DNA damage checkpoint. Inhibition of Chk1 is predicted to enhance the effects of antimetabolites, such as gemcitabine.

Methods: This study is a Phase 1–2 study in patients with solid tumors (Phase 1) and advanced pancreatic adenocarcinoma (Phase 2). In Phase 1, gemcitabine (1000 mg/m2) was administered on Days 1, 8, and 15 of a 28-day cycle. LY2603618 was administered on Days 2, 9, and 16. Patients were assessed for safety, tolerability, and dose-limiting toxicity (DLT). A recommended Phase 2 dose (RP2D) was determined based on safety, dose intensity, and pharmacokinetics (PK).

Results: A total of 50 patients were enrolled. Patients were treated at 70 (n =3), 105 (n=3), 150 (n=7), 200 (n=11), 250 (n=6) mg/m2and at 2 additional flat-fixed dose cohorts of 200 (n=10) and 230 (n=10) mg. The most frequent AEs reported included fatigue, thrombocytopenia, anemia, nausea, neutropenia, and constipation, which are consistent with those reported with gemcitabine monotherapy. During escalation, DLTs included neutropenia, infusion-related reaction and thrombocytopenia, with thrombocytopenia being dose limiting. The maximum tolerated dose (MTD) was determined to be 200 mg/m2. The systemic exposure of LY2603618 increased in a dose-dependent manner and the LY2603618 systemic clearance was dose-independent across all doses on average. The mean LY2603618 half-life varied across doses but was consistent with a half-life (i.e., &gt;10 hr and &lt;24 hr) suitable for maintaining required human exposures while minimizing intra and intercycle accumulation. The administration of gemcitabine approximately 24 hours before LY2603618 administration did not alter LY2603618 PK. Following dose escalation, identification of the MTD and results from a population PK analysis, 2 additional flat-fixed dose cohorts of 200 and 230 mg (n=10 in each cohort) were added in an effort to minimize dose reduction/omissions of gemcitabine and reduce PK variability. At a dose of 230 mg, the plasma exposures that correlate with the maximal pharmacodynamic (PD) effect in nonclinical models (i.e., AUC(0−∞) &gt;21,000 ng hr/mL and Cmax &gt; 2000 ng/mL) were achieved by all but one patient. Based on safety/tolerability, the ability to maintain dose intensity, and PK, a RP2D of 230 mg was selected. A total of 17 of 30 patients received more than 2 cycles of therapy.

Conclusions: LY2603618 administered in combination with gemcitabine demonstrated an acceptable safety profile; the MTD for this regimen was defined at 200 mg/m2 in the originally designed study. However at a fixed dose of 230 mg, LY2603618 in combination with gemcitabine had an acceptable safety profile and the observed exposures exceed those required for biological effect in nonclinical models. This dose is being evaluated in the Phase 2 component of the study.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2011 Nov 12-16; San Francisco, CA. Philadelphia (PA): AACR; Mol Cancer Ther 2011;10(11 Suppl):Abstract nr A94.

Phase I study of Oral gemcitabine prodrug (LY2334737) alone and in combination with erlotinib in patients with advanced solid tumors

PURPOSE

LY2334737 is an orally available prodrug of gemcitabine. The objective of this study was to determine the maximum tolerated dose (MTD) and dose limiting toxicities (DLT) of daily administration of LY2334737 with or without erlotinib.

EXPERIMENTAL DESIGN

Patients with advanced or metastatic cancer were treated with escalating doses of LY2334737 monotherapy or in combination with continuous daily administration of 100 mg erlotinib. LY2334737 was given once daily for 14 days of a 21-day cycle. The study was extended with a bioequivalence trial to investigate a novel LY2334737 drug formulation.

RESULTS

A total of 65 patients were treated in this study. The MTD was 40 mg LY2334737. Fatigue was the most frequent DLT for LY2334737 monotherapy (4 patients) followed by elevated transaminase levels (2 patients), both observed at the 40- to 50-mg dose levels. Among the 10 patients in the combination arm, 2 had DLTs at the 40-mg dose level. These were fatigue and elevated liver enzyme levels. The most common adverse events were fatigue (n = 38), nausea (n = 27), vomiting (n = 24), diarrhea (n = 23), anorexia (n = 20), pyrexia (n = 18), and elevated transaminase levels (n = 14). The pharmacokinetics showed dose proportional increase in LY2334737 and gemcitabine exposure. The metabolite 2',2'-difluorodeoxyuridine accumulated with an accumulation index of 4.3 (coefficient of variation: 20%). In one patient, complete response in prostate-specific antigen was observed for 4 cycles, and stable disease was achieved in 22 patients overall. Pharmacokinetic analysis showed that the 2 investigated LY2334737 drug formulations were bioequivalent.

CONCLUSIONS

LY2334737 displays linear pharmacokinetics and the MTD is 40 mg with or without daily administration of 100 mg erlotinib. Signs of antitumor activity warrant further development.

Phase I study of oral gemcitabine prodrug (LY2334737) alone and in combination with erlotinib in patients (pts) with advanced solid tumors

2576

Background: LY2334737 (LY) is an orally available valproic acid prodrug of gemcitabine that was developed to overcome the extensive first-pass metabolism of gemcitabine to 2',2'-difluorodeoxyuridine (dFdU). The objectives of this study were to determine the maximum tolerated dose (MTD), dose limiting toxicity (DLT) and pharmacokinetics (PK) of LY as monotherapy and in combination with erlotinib. Methods: Eligible pts had ECOG PS < 2 and adequate hematologic, renal and hepatic function. In Arm A, LY was given daily for 14 days in a 3-week cycle. Pts assigned to Arm B also received erlotinib daily 100 mg continuously. Dose escalation was based on observed toxicity and the modified continual reassessment method (mCRM). The dose was maximally increased by 100% depending on the toxicity observed in the previous cohort. PK of LY, gemcitabine, dFdU and intracellular metabolites were determined. Results: 33 pts (21 m, 12 f, median age 60 yrs (range 24–81)) were treated at 5 different dose-levels (range 5–50 mg/day). Pts received a median of 3 cycles (range 2–17). Three out of 7 pt treated with 50 mg experienced 5 dose limiting toxicities (DLT). DLTs observed at 40 and 50 mg include fatigue (4 pt), thrombocytopenia (1 pt), GGT elevation (1 pt), AST/ALT elevation (1 pt), fever (1 pt), and pulmonary embolism (1 pt). One death was possibly related to LY intake. This pt, treated with 40 mg LY, developed on day 15 dyspnea, hypovolemic shock, and suddenly died. No grade 3 or 4 toxicities were reported at dose-levels < 40 mg. The most common adverse events were fatigue, vomiting, nausea, pyrexia, anorexia, and diarrhea. Two pts with mesothelioma were stable for > 9 months. One pt with refractory prostate cancer presented a PSA CR as assessed by investigator. The PK show dose-proportional increase in exposure of both LY and gemcitabine. Both LY and gemcitabine are rapidly cleared, thus no accumulation occurs. The metabolite dFdU accumulates due to its long half life. Conclusions: LY displays linear PK. The dose level of 50-mg is non-tolerable and 40-mg is being confirmed as the MTD as single agent and in combination with 100 mg erlotinib. Antitumor activity warrants further development. Pt accrual is ongoing.

[Table: see text]

Gemcitabine and oxaliplatin combination: a multicenter phase II trial in unfit patients with locally advanced or metastatic urothelial cancer

BACKGROUND

Up to 50% of patients with bladder cancer cannot be treated with cisplatin because they are considered unfit due to poor renal function. Gemcitabine and oxaliplatin are active, nonnephrotoxic therapies with nonoverlapping toxicity profiles that provide an alternative therapy for this group of patients.

PATIENTS AND METHODS

In a multicenter study, patients received gemcitabine 1200 mg/m(2) on days 1 and 8 and oxaliplatin 100 mg/m(2) on day 8 every 21 days. Eligible criteria were creatinine clearance >30 ml/min and/or Eastern Cooperative Oncology Group (ECOG) performance status of two or less.

RESULTS

Forty-six patients were assessable for response and toxicity. Median age was 69 years (range 52-85), median ECOG two (range 0-2). Median number of metastatic sites was 2 (range 1-6). Median creatinine clearance was 50.73 ml/min (range 30-87). A total of 187 cycles were given with a median of 5 (range 1-6). Hematological toxicity was mild with grade 3-4 peripherical neuropathy occurring in 4% of patients. Overall response rate was 48% (three complete response, 19 partial response, seven stable disease and 17 progressive disease). Median time to disease progression was 5 months.

CONCLUSION

Gemcitabine-oxaliplatin is an active and tolerable combination with response rate that merits further study in patients with impaired renal function but good performance status.

Phase I study of bi-weekly pemetrexed (P) plus cisplatin (C) in patients with advanced cancer

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Background: Cisplatin and pemetrexed have demonstrated clinical activity in several malignant tumors including mesothelioma and non small cell lung cancer. There is preclinical evidence of synergism between both agents as well as clinical non-overlapping toxicities, thus providing the rationale for their evaluation in combination. Our aim was to develop a well-tolerated combination of bi-weekly CP able to deliver higher dose intensity than the every 3-week standard. Methods: Escalating doses of P from a starting dose level of 300 mg/m2, with a fixed-dose of C 50 mg/m2, both biweekly on 28-day cycles, were administered to patients with refractory advanced solid malignancies and calculated creatinine clearance = 45 mL/min. Results: Twenty one patients (5 female/16 male); median age 61 (39–76); ECOG 0 (16), 1 (5); lung cancer (9); soft-tissue sarcoma (3); unknown primary, bladder, breast, rectum, esophagus, melanoma, mesothelioma, prostate, and tonsil (1, each) have received a total of 48 courses (median 2, range 0–5), at P dose levels of 300 mg/m2 [8 pts, Dose level 1 (DL1)], 400 mg/m2 (7 pts, DL2), and 500 mg/m2 (6 pts, DL3), with full doses of C. Four patients were non-evaluable (2 at DL1, 1 at DL2 and 1 at DL3) because of early PD (2) and non-drug related serious adverse event (2 pt). Dose Limiting Toxicities (DLT) were G4 neutropenia (1 pt) at 300 mg/m2; and prolonged G 1/2 thrombocytopenia (1 pt) at 500 mg/m2. There were also 2 pts with non-DLT G4 neutropenia at DL3. The rest of toxicities were mild to moderate being the most frequent asthenia, nausea, anorexia, stomatatis, and sensory neuropathy. DL3 was considered the Maximum Tolerated Dose (MTD) and the previous level with P at 400 mg/m2 was declared the recommended phase II dose. Three additional patients were treated at DL2 for dose confirmation. A PR has been observed in 2 pts with NSCLC, 1 pt with breast, and 1 with esophagus cancer. Conclusions: Biweekly administration of pemetrexed (400 mg/m2) plus cisplatin (50 mg/m2) is clinically well tolerated and can be used safely. The regimen delivers higher dose intensity of P and equal of C as the standard. This regimen is currently being studied in a phase 2 trial in patients with locally advanced, non resectable or metastatic urothelial cancer.

No significant financial relationships to disclose.

Assessment of the value of confirming responses in clinical trials in oncology

The requirement for a second assessment to confirm initial tumour response is required by all response guidelines. Its rationale, however, is not clear. We have conducted this study to compare validity of response rate assessment determined with and without secondary confirmation. Using specified criteria, nine trials of one single cytotoxic drug including 416 patients were selected from a pharmaceutical database. Objective response rates were determined by a single determination and by two separate determinations. 81 responses (19.5%, [15.8-23.6%]) were scored by the confirmation method and 97 responses (23.3% [19.3-27.7%]) by the no-confirmation method. The Kappa (kappa) coefficient of 0.89 indicates good agreement between both methods. This is the first study that systematically compares response rates calculated with and without performing response confirmation. Results show good agreement between both methods. We suggest that assessing response without confirmation may be the preferred method. These results should be confirmed by additional studies in a variety of cancer settings.

PHASE I PHARMACOKINETIC STUDY OF A SINGLE INTRAVESICAL INSTILLATION OF GEMCITABINE ADMINISTERED IMMEDIATELY AFTER TRANSURETHRAL RESECTION PLUS MULTIPLE RANDOM BIOPSIES IN PATIENTS WITH SUPERFICIAL BLADDER CANCER

PURPOSE

In this phase I study we determined the pharmacokinetic and toxicity profiles of a single intravesical instillation of gemcitabine administered immediately after complete transurethral resection (TUR) plus multiple random biopsies.

MATERIALS AND METHODS

Ten patients with superficial bladder cancer clinically staged as Ta/T1 with no carcinoma in situ were included. A single dose of gemcitabine was administered intra-vesically immediately after TUR plus 6 random biopsies. Five patients received 1,500 mg and 5 received 2,000 mg diluted in 100 ml saline. Retention time in the bladder was 60 minutes. Concentrations of gemcitabine and dFdU (2',2'-difluoro-2'-deoxyuridine) were determined by high pressure liquid chromatography assay.

RESULTS

Treatment was clinically well tolerated in all patients. Two patients in the 1,500 mg group had minimal hipogastric discomfort and 1 in the 2,000 mg group had grade 1 bladder spasms. There was no remarkable systemic toxicity on hematology or biochemistry at any dose level on day 12 or 30. One patient per dose level showed tumor recurrence on 3-month repeat cystourethroscopy. Mean maximum gemcitabine concentration was 1.8 microg/ml and the mean last AUC was 158 microg/ml*minute. There was large interpatient variability but no significant differences between the 2 dose levels.

CONCLUSIONS

Single intravesical instillation of gemcitabine immediately after TUR and multiple random biopsies for superficial bladder cancer are a safe and well tolerated treatment. The favorable toxicity and pharmacokinetic profiles of intravesical gemcitabine support future phase II studies with this agent.

The role of extreme phenotype selection studies in the identification of clinically relevant genotypes in cancer research

The investigation of genetic alterations that may be related to the prognosis of patients with malignant disease has become a frequently used strategy in recent years. Although some conclusions have been reached in certain studies, the complexity and the multifactorial nature of most neoplastic diseases makes it difficult to identify clinically relevant information, and the results of some studies have been of borderline significance or have been conflicting. In contrast, the identification and the study of patients or families with very characteristic phenotypes have yielded outstanding results in the identification of the genetic characteristics underlying such phenotypes. Although, in most cases, the individuals who are selected for these types of studies are characterized by a negative phenotype (i.e., individuals who are at increased risk for developing a specific disease), a few studies have been directed toward individuals with phenotypes that imply an unusually good prognosis (i.e., individuals who present with a decreased risk for developing specific diseases despite an important exposure to well-known risk factors). Therefore, it seems logical to develop this strategy further as a valid methodology for the study of other diseases, such as cancer. The study of individuals with phenotypes that imply an extremely good prognosis, such as long-term survivors of theoretically incurable malignancies or individuals who seem to be protected against a certain neoplastic disorder despite having a markedly increased risk for its development, may unveil genetic alterations that explain such characteristic phenotypes and may provide potentially useful therapeutic targets against these diseases.

A family of bicistronic vectors to enhance both local and systemic antitumor effects of HSVtk or cytokine expression in a murine melanoma model

The herpes simplex virus-thymidine kinase/ganciclovir (HSVtk/GCV) system produces both direct and immune-mediated tumor cell killing. Here, we compare the efficacy of HSVtk/GCV with cytokines, alone and in combination, on the tumorigenicity and immunogenicity of B16 cells. With respect to single gene modifications, only HSVtk/GCV, or high-level interleukin-2 (IL-2) secretion, completely prevented tumor growth, whereas granulocyte-macrophage colony-stimulating factor (GM-CSF) generated the best levels of long-term systemic protection. To augment both local killing and immune activation, we constructed bicistronic constructs that express HSVtk and a cytokine within the same cell. Co-expression of HSVtk with IL-2 or GM-CSF enhanced the local antitumor activity of any gene alone. In a tumor-prevention model, HSVtk killing, in an environment preprimed with GM-CSF, generated the best long-term immune protection. However, in a short-term therapy model, continued IL-2 expression was most effective against 3-day established tumors. This probably reflects differences in the activities of IL-2 and GM-CSF in generating short-term, nonspecific immune stimulation compared to long-term immunological memory, respectively. As a prelude to in vivo delivery experiments, we also demonstrated that these bicistronic cassettes can be packaged normally into retroviral (5 x 10(5) virus/ml from pooled populations) and adenoviral vectors (5 x 10(9) virus/ml) and function as predicted within virally infected cells. This family of bicistronic vectors can be used to stimulate synergy between suicide and cytokine genes, overcomes the problems of delivering two genes on separate vectors, and should allow easier preparation of vectors for the delivery of multiple genes to patients' tumor cells.