Temozolomide (TMZ) has remained the chemotherapy of choice in patients with glioblastoma multiforme (GBM) primarily due to the lack of more effective drugs. Tumors, however, quickly develop resistance to this line of treatment creating a critical need for alternative approaches and strategies to resensitize the cells. Withaferin A (WA), a steroidal lactone derived from several genera of the Solanaceae plant family has previously demonstrated potent anti-cancer activity in multiple tumor models. Here, we examine the effects of WA against TMZ-resistant GBM cells as a monotherapy and in combination with TMZ. WA prevented GBM cell proliferation by dose-dependent G2/M cell cycle arrest and cell death through both intrinsic and extrinsic apoptotic pathways. This effect correlated with depletion of principle proteins of the Akt/mTOR and MAPK survival and proliferation pathways with diminished phosphorylation of Akt, mTOR, and p70 S6K but compensatory activation of ERK1/2. Depletion of tyrosine kinase cell surface receptors c-Met, EGFR, and Her2 was also observed. WA demonstrated induction of N-acetyl-L-cysteine-repressible oxidative stress as measured directly and through a subsequent heat shock response with HSP32 and HSP70 upregulation and decreased HSF1. Finally, pretreatment of TMZ-resistant GBM cells with WA was associated with O6-methylguanine-DNA methyltransferase (MGMT) depletion which potentiated TMZ-mediated MGMT degradation. Combination treatment with both WA and TMZ resulted in resensitization of MGMT-mediated TMZ-resistance but not resistance through mismatch repair mutations. These studies suggest great clinical potential for the utilization of WA in TMZ-resistant GBM as both a monotherapy and a resensitizer in combination with the standard chemotherapeutic agent TMZ.
Withaferin A; glioblastoma multiforme; temozolomide resistance; oxidative stress; heat shock response; Akt/mTOR pathway; O6-methylguanine-DNA methyltransferase
Dasatinib has been shown preclinically to overcome resistance to gemcitabine. We evaluated the safety and biological activity of the combination of dasatinib and gemcitabine in patients with advanced solid tumors.
In a phase 1 study (3+3 design), patients received daily dasatinib with weekly gemcitabine on days 1, 8 and 15 of a 28-day cycle (except cycle 1 which was eight weeks). Dose escalation began with dasatinib 70mg orally (PO) daily and gemcitabine 800mg/m2 intravenously (IV) weekly.
Forty-seven patients (15 men; median age = 55 years; median number of prior systemic treatments = 4) were enrolled. Dose-limiting toxicities were grade 3 fatigue and dehydration, with the maximum tolerated dose being dasatinib 100mg PO qd and gemcitabine 600mg/m2 IV weekly. The most common grade 3–4 toxicities were anemia (21.5%), thrombocytopenia (26.2%), leukopenia (26.2%), and pleural effusion (10.7%). Six of 47 patients attained stable disease (SD) ≥ 6 months or partial response including 2 of 8 patients with pancreatic cancer (SD ≥ 6 months; both gemcitabine-refractory), 2 of 3 patients with thymoma (SD for 9.8 and 15 months), 1 of 1 patient with anal squamous cancer (SD 15 months) and 1 of 5 patients with inflammatory breast cancer. No significant changes in circulating tumor cells or interleukin-8 levels were observed.
The combination was well tolerated at doses of dasatinib 100mg PO daily and gemcitabine 600mg/m2 IV weekly. SD ≥ 6 months/ PR was observed in gemcitabine-refractory pancreatic cancer, thymoma, anal cancer and inflammatory breast cancer.
dasatinib; gemcitabine; pancreatic cancer; phase 1; advanced solid tumors
Rhenium (I)-diselenother (Re-diselenoether) is a water soluble metal-based compound, combining one atom of rhenium and two atoms of selenium. This compound has been reported to exhibit marked activities against several solid tumor cell lines. We now disclose an improved synthesis of this complex. The Re-diselenoether showed a potent inhibitory effect on MDA-MB231 cell division in vitro, which lasted when the complex was no longer present in the culture. Re-diselenoether induced a remarkable reduction of the volume of the primitive breast tumors and of the pulmonary metastases without clinical signs of toxicity, in mice-bearing a MDA-MB231 Luc+ tumor, orthotopically transplanted, after a daily oral administration at the dose of 10 mg/kg/d. Interestingly, an antagonism was observed when cisplatin was administered as a single i.p. injection 1 week after the end of the Re-diselenoether administration. In an effort to gain insight of the mechanisms of action of Re-diselenoether complex, interaction with 9-methylguanine as a nucleic acid base model was studied. We have shown that Re-diselenoether gave both mono- and bis-guanine Re adducts, the species assumed to be responsible for the DNA intrastrand lesions.
Electronic supplementary material
The online version of this article (doi:10.1007/s10637-015-0265-z) contains supplementary material, which is available to authorized users.
Rhenium; Selenium; Breast cancer; MDA-MB231 cell line; Bioluminescence
Background Although DNA-directed alkylating agents and related compounds have been a mainstay in chemotherapeutic protocols due to their ability to readily interfere with the rapid mitotic progression of malignant cells, their clinical utility is limited by DNA repair mechanisms and immunosuppression. However, the same destructive nature of alkylation can be reciprocated at the cell surface using novel plasma membrane alkylating agents. Results Plasma membrane alkylating agents have elicited long term survival in mammalian models challenged with carcinomas, sarcomas, and leukemias. Further, a specialized group of plasma membrane alkylating agents known as tetra-O-acetate haloacetamido carbohydrate analogs (Tet-OAHCs) potentiates a substantial leukocyte influx at the administration and primary tumor site, indicative of a potent immune response. The effects of plasma membrane alkylating agents may be further potentiated through the use of another novel class of chemotherapeutic agents, known as dihydroxyacetone phosphate (DHAP) inhibitors, since many cancer types are known to rely on the DHAP pathway for lipid synthesis. Conclusion Despite these compelling data, preliminary clinical trials for plasma membrane-directed agents have yet to be considered. Therefore, this review is intended for academics and clinicians to postulate a novel approach of chemotherapy; altering critical malignant cell signaling at the plasma membrane surface through alkylation, thereby inducing irreversible changes to functions needed for cell survival.
Plasma membrane; Alkylating agents; Leukocyte influx; Carbohydrate analogs; Dihydroxyacetone phosphate inhibitors
3-Aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP, Triapine®) is a novel small molecule inhibitor of ribonucleotide reductase (RR) with clinical signs of activity in pancreatic cancer. Therefore, the Phase 2 Consortium (P2C) initiated a trial (two single stage studies with planned interim analysis) of 3-AP at 96 mg/m2 intravenously days 1–4 and 15–18 of a 28-day cycle in both chemotherapy-naive and gemcitabine-refractory (GR) patients with advanced pancreatic cancer. The primary endpoint was survival at six months (chemotherapy-naive) and four months (GR). Secondary endpoints were toxicity, response, overall survival, time to progression and mechanistic studies. Fifteen patients were enrolled including one chemotherapy-naïve and 14 GR. The chemotherapy-naïve patient progressed during cycle 1 with grade 3 and 4 toxicities. Of 14 GR patients, seven received two cycles, six received one cycle and one received eight cycles. Progression precluded further treatment in 11 GR patients. Additionally, one died of an ileus in cycle 1 considered related to treatment and two stopped treatment due to toxicity. Five GR patients had grade 4 toxicities possibly related to 3-AP and six GR patients had grade 3 fatigue. Toxicities and lack of meaningful clinical benefit prompted early study closure. Four-month survival in GR patients was 21% (95% CI: 8–58%). Correlative studies confirmed that 3-AP increased the percentage of S-phase buccal mucosal cells, the presence of multidrug resistance gene polymorphisms appeared to predict leukopenia, and baseline pancreatic tumor RR M2 expression was low relative to other tumors treated with 3-AP. In conclusion, this regimen appears inactive against predominantly GR pancreatic cancer. RR M2 protein may not have a critical role in the malignant potential of pancreatic cancer.
Pancreatic cancer; Triapine; 3-aminopyridine-2-carboxaldehyde thiosemicarbazone; 3-AP; Ribonucleotide reductase
Recurrent malignant brain tumors (RMBTs) carry a poor prognosis. Dichloroacetate (DCA) activates mitochondrial oxidative metabolism and has shown activity against several human cancers.
We conducted an open-label study of oral DCA in 15 adults with recurrent WHO grade III – IV gliomas or metastases from a primary cancer outside the central nervous system. The primary objective was detection of a dose limiting toxicity for RMBTs at 4 weeks of treatment, defined as any grade 4 or 5 toxicity, or grade 3 toxicity directly attributable to DCA, based on the National Cancer Institute’s Common Toxicity Criteria for Adverse Events, version 4.0. Secondary objectives involved safety, tolerability and hypothesis-generating data on disease status. Dosing was based on haplotype variation in glutathione transferase zeta 1/maleylacetoacetate isomerase (GSTZ1/MAAI), which participates in DCA and tyrosine catabolism.
Eight patients completed at least 1 four week cycle. During this time, no dose-limiting toxicities occurred. No patient withdrew because of lack of tolerance to DCA, although 2 subjects experienced grade 0–1 distal parasthesias that led to elective withdrawal and/or dose-adjustment. All subjects completing at least 1 four week cycle remained clinically stable during this time and remained on DCA for an average of 75.5 days (range 26–312).
Chronic, oral DCA is feasible and well-tolerated in patients with recurrent malignant gliomas and other tumors metastatic to the brain using the dose range established for metabolic diseases. The importance of genetic-based dosing is confirmed and should be incorporated into future trials of chronic DCA administration.
Dichloroacetate; Malignant (high grade) glioma; Warburg effect; Pyruvate dehydrogenase complex; Pyruvate dehydrogenase kinase; Phase 1 trial
To determine the effectiveness of bortezomib plus irinotecan and bortezomib alone in patients with advanced gastroesophageal junction (GEJ) and gastric adenocarcinoma. We also sought to explore the effect of these therapeutics on tumor and normal gene expression in vivo.
Forty-one patients with advanced GEJ (89%) or gastric (11%) adenocarcinoma received bortezomib (1.3 mg/m2 days 1, 4, 8, 11) plus irinotecan (125 mg/m2 days 1, 8) every 21 days as first line therapy (N=29), or bortezomib alone as second line therapy (N=12). The trial was designed to detect a 40% response rate for the combination, and 20% response rate for bortezomib alone. Affymetrix HU133A gene chip arrays were used for gene expression studies.
Objective response occurred in 3 of 29 patients (10%, 95% confidence intervals [CI] 2%, 27%) treated with bortezomib plus irinotecan, and in 1 of 12 patients (8%, 95% CI 0%, 39%) with bortezomib alone. Due to the limited number of responders, there were no significant correlations with response found in the gene expression profiles of 12 patients whose tumors were sampled before and 24 hours after therapy with bortezomib alone (N=2) or the combination (N=10).
We conclude that bortezomib is not effective for the treatment of advanced adenocarcinoma of the GEJ or stomach, whether used alone or in combination with irinotecan, in an unselected patient population.
Bortezomib; Proteasome inhibitor; Irinotecan; Gastroesophageal Junction; Adenocarcinoma; Combination Therapy; Microarray
This phase II trial investigated chemoradiation followed by surgery and 2 years of adjuvant tetrathiomolybdate (TM) for resectable esophageal cancer.
Patients with resectable, locally advanced esophageal cancer received neoadjuvant cisplatin 60 mg/m2 (days 1 and 22), paclitaxel 60 mg/m2 (days 1, 8, 15, and 22), and 45 Gy hyperfractionated radiotherapy for 3 weeks followed by transhiatal esophagectomy. TM 20 mg PO QD was started 4 weeks post-op, and continued for 2 years to maintain the ceruloplasmin level between 5 and 15 mg/dl.
Sixty-nine patients were enrolled (median age, 60 years). Sixty-six patients underwent surgery and 61 patients had a complete resection. Histologic complete response rate was 10 %. Twenty-one patients did not receive TM (metastases noted in the peri-operative period, prolonged post-operative recovery time, or patient refusal). Forty-eight patients started TM; 14 completed 24 months of treatment, 11 completed 10–18 months, 15 completed 2–8 months, and 8 completed ≤1 month. Twenty-seven patients had disease recurrence. With a median follow-up of 55 months, 25 patients were alive without disease, 1 was alive with disease, and 43 have died. Three-year recurrence-free survival was 44 % (95 % CI, 32–55 %) and the three-year overall survival was 45 % (95 % CI 33–56 %).
TM is an antiangiogenic agent that is well tolerated in the adjuvant setting. Disease-free survival and overall survival are promising when compared to historical controls treated at our institution with a similar regimen that did not include TM. However, the challenges associated with prolonged administration limit further investigation.
Esophageal cancer; Neoadjuvant chemoradiation; Tetrathiomolybdate; Cisplatin; Paclitaxel
Background Ipilimumab is an antibody that targets the cytotoxic T-lymphocyte antigen-4 to potentiate an antitumor response. Adding ipilimumab 10 mg/kg to paclitaxel (PTX) and carboplatin (CBDCA) in a phased schedule improved progression-free survival in a phase II non-small-cell lung cancer (NSCLC) study. Methods This dose-escalating, phase I study was designed to identify the recommended dose of ipilimumab (3 or 10 mg/kg) by evaluating dose-limiting toxicity (DLT; Cycles 3 and 4) in phased combination with PTX (175 mg/m2) and CBDCA (area under the curve = 6) in Japanese patients with advanced NSCLC. Treatment was administered intravenously every 3 weeks initially, followed by some eligible patients receiving maintenance ipilimumab once every 12 weeks. Additional endpoints included safety, tumor response, pharmacokinetics, and immunogenicity. Results Fifteen patients were enrolled and 12 received ipilimumab (n = 6, 3 mg/kg; n = 6, 10 mg/kg) in combination with PTX and CBDCA. DLTs occurred in 2 patients (ipilimumab 3 mg/kg) and 1 patient (ipilimumab 10 mg/kg). The most common grade 3/4 adverse events (AEs) were decreased hemoglobin, leukopenia, and neutropenia. The most common immune-related AEs affected the skin, gastrointestinal, and nervous system. The safety profile was similar in both cohorts. Three patients in each cohort achieved a partial response. The pharmacokinetic (PK) profile of ipilimumab in Japanese patients was similar to that observed in previous studies in non-Japanese patients. Conclusions The recommended dose of ipilimumab in phased combination with PTX and CBDCA in Japanese patients with NSCLC was identified as 10 mg/kg. The safety profile was consistent with the previously defined AE profile.
Ipilimumab; Paclitaxel; Carboplatin; Non-small-cell lung cancer; Phase I study; Japanese patients
Transforming growth factor-beta (TGF-β) signaling plays a key role in epithelial-mesenchymal transition (EMT) of tumors, including malignant glioma. Small molecule inhibitors (SMI) blocking TGF-β signaling reverse EMT and arrest tumor progression. Several SMIs were developed, but currently only LY2157299 monohydrate (galunisertib) was advanced to clinical investigation.
The first-in-human dose study had three parts (Part A, dose escalation, n=39; Part B, safety combination with lomustine, n=26; Part C, relative bioavailability study, n = 14).
A preclinical pharmacokinetic/pharmacodynamic (PK/PD) model predicted a therapeutic window up to 300 mg/day and was confirmed in Part A after continuous PK/PD. PK was not affected by co-medications such as enzyme-inducing anti-epileptic drugs or proton pump inhibitors. Changes in pSMAD2 levels in peripheral blood mononuclear cells were associated with exposure indicating target-related pharmacological activity of galunisertib. Twelve (12/79; 15 %) patients with refractory/relapsed malignant glioma had durable stable disease (SD) for 6 or more cycles, partial responses (PR), or complete responses (CR). These patients with clinical benefit had high plasma baseline levels of MDC/CCL22 and low protein expression of pSMAD2 in their tumors. Of the 5 patients with IDH1/2 mutation, 4 patients had a clinical benefit as defined by CR/PR and SD ≥6 cycles. Galunisertib had a favorable toxicity profile and no cardiac adverse events.
Based on the PK, PD, and biomarker evaluations, the intermittent administration of galunisertib at 300 mg/day is safe for future clinical investigation.
TGF-β inhibitor; Galunisertib; First-in-Human Dose; Glioma; Pharmacokinetics; Pharmacodynamics
To establish the recommended phase II dose of the oral γ-secretase inhibitor RO4929097 (RO) in combination with gemcitabine; secondary objectives include the evaluation of safety, tolerability, pharmacokinetics, biomarkers of Notch signaling and preliminary anti-tumor activity.
Patients with advanced solid tumors were enrolled in cohorts of escalating RO dose levels (DLs). Tested RO DLs were 20 mg, 30 mg, 45 mg and 90 mg. RO was administered orally, once daily on days 1–3, 8–10, 15–17, 22–24. Gemcitabine was administered at 1000mg/m2 on d1, 8, and 15 in 28d cycles. Dose limiting toxicities (DLTs) were assessed by CTCAE v4. Serial plasma was collected for RO (total and unbound) and gemcitabine pharmacokinetic analysis. Biomarkers of Notch signaling were assessed by immunohistochemistry in archival tissue. Antitumor activity was evaluated (RECIST 1.1).
A total of 18 patients were enrolled to establish the recommended phase II dose. Of these, 3 patients received 20mg RO, 7 patients received 30mg RO, 6 patients received 45mg RO and 2 patients received 90mg RO. DLTs were grade 3 transaminitis (30 mg RO), grade 3 transaminitis and maculopapular rash (45 mg RO), and grade 3 transaminitis and failure to receive 75% of planned RO doses secondary to prolonged neutropenia (90 mg); all were reversible. The maximum tolerated dose was exceeded at 90 mg RO.
Pharmacokinetic analysis of both total and free RO confirmed the presence of autoinduction at 45 and 90 mg. Median levels of Notch3 staining were higher in individuals who received fewer than 4 cycles (p=0.029). Circulating angiogenic factor levels did not correlate with time to progression or ≥grade 3 adverse events. Best response (RECIST 1.1) was partial response (nasopharyngeal cancer) and stable disease > 4 months was observed in 3 patients (pancreas, tracheal, and breast primary cancers).
RO and gemcitabine can be safely combined. The recommended phase II dose of RO was 30mg in combination with gemcitabine 1000mg/m2. Although RO exposure was limited by the presence of autoinduction, RO levels achieved exceeded the area under the concentration-time curve for 0–24 hours (AUC0–24) predicted for efficacy in preclinical models using daily dosing. Evidence of clinical antitumor activity and prolonged stable disease were identified.
phase I; RO4929097; Notch inhibition; gemcitabine
A phase I, dose-escalation study of AT-101 with cisplatin and etoposide was conducted to determine the maximum tolerated dose (MTD)/recommended phase 2 dose (RP2D), safety and pharmacokinetics in patients with advanced solid tumors, with an expanded cohort in patients with extensive-stage small cell lung cancer (ES-SCLC) to assess preliminary activity.
In the dose escalation portion, increasing doses of AT-101 were administered orally BID on days 1–3 along with cisplatin on day 1 and etoposide on days 1–3 of a 21 day cycle. At the RP2D, an additional 7 patients with untreated ES-SCLC were enrolled.
Twenty patients were enrolled in the dose-escalation cohort, and 7 patients with ES-SCLC were enrolled in the expanded cohort. The MTD/RP2D was established at AT-101 40 mg BID days 1–3 with cisplatin 60 mg/m2 and etoposide 120 mg/m2 on day 1 of a 21 day cycle with pegfilgrastim support. Two DLTs of neutropenic fever were seen at dose level 1. After the addition of pegfilgrastim, no additional DLTs were observed. Grade 3/4 treatment-related toxicities included: diarrhea, increased AST, neutropenia, hypophosphatemia, hyponatremia, myocardial infarction and pulmonary embolism. No apparent PK interactions were observed between the agents. Preliminary activity was observed with PRs in patients with ES-SCLC, high-grade neuroendocrine tumor, esophageal cancer and NSCLC.
AT-101 with cisplatin and etoposide is well tolerated with growth factor support. Anti-tumor activity was observed in a variety of cancers including ES-SCLC, supporting further investigation with BH-3 mimetics in combination with standard chemotherapy for ES-SCLC.
AT-101; cisplatin; etoposide; phase I; extensive-stage small cell lung cancer
Accumulating evidence shows evidence of efficacy with the combination of vorinostat and bortezomib in solid tumors. We previously examined a once-daily continuous dosing schedule of vorinostat in combination with bortezomib which was well tolerated in cycles 1 and 2; however, there was concern regarding the tolerability through multiple cycles. This study was conducted to evaluate an intermittent dosing schedule of vorinostat with bortezomib.
Vorinostat was initially administered orally twice daily on days 1–14 with bortezomib IV on days 1, 4, 8, and 11 of a 21 day cycle. Two DLTs (elevated ALT and fatigue) were observed at dose level 1, thus the protocol was amended to administer vorinostat intermittently twice daily on days 1–4 and 8–11.
29 patients were enrolled; 13 men and 16 women. Common cancer types included sarcoma, pancreatic, colorectal, GIST, and breast. The most common Grade 3–4 toxicities at any dose level included thrombocytopenia, fatigue, increased ALT, elevated INR, and diarrhea. DLTs in the intermittent dosing scheduled included thrombocytopenia and fatigue. The Cmax and AUC for the intermittent dosing regimen were similar to those observed in the daily dosing. In this heavily pretreated population, stable disease was observed in patients with sarcoma, colorectal adenocarcinoma and GIST.
The MTD was established at vorinostat 300 mg BID on days 1–4 and 8–11 and bortezomib 1.3 mg/m2 IV on days 1, 4, 8, and 11 of a 21 day cycle. Tolerability was not improved with the intermittent dosing schedule of vorinostat when compared to continuous dosing.
SAHA; vorinostat; PS-341; bortezomib; phase I
Activation of the vascular endothelial growth factor receptor (VEGFR) and the oncogenic Src pathway has been implicated in the development of castration-resistant prostate cancer (CRPC) in preclinical models. Cediranib and dasatinib are multi-kinase inhibitors targeting VEGFR and Src respectively. Phase II studies of cediranib and dasatinib in CRPC have shown single agent activity.
Docetaxel-pretreated CRPC patients were randomized to arm A: cediranib alone (20 mg/day) versus arm B: cediranib (20 mg/day) plus dasatinib (100 mg/day) given orally on 4-week cycles. Primary endpoint was 12-week progression-free survival (PFS) as per the Prostate Cancer Clinical Trials Working Group (PCWG2). Patient reported outcomes were evaluated using Functional Assessment of Cancer Therapy- Prostate (FACT-P) and Present Pain Intensity (PPI) scales. Correlative studies of bone turnover markers (BTM), including bone alkaline phosphate (BAP) and serum beta-C telopeptide (B-CTx) were serially assayed.
A total of 22 patients, 11 per arm, were enrolled. Baseline demographics were similar in both arms. Median number of cycles =4 in arm A (range 1–12) and 2 in arm B (range 1–9). Twelve-week PFS was 73 % in arm A versus 18 % in arm B (p=0.03). Median PFS in months (arm A versus B) was: 5.2 versus 2.6 (95 % CI: 1.9–6.5 versus 1.4-not reached). Most common grade 3 toxicities were hypertension, anemia and thrombocytopenia in arm A and hypertension, diarrhea and fatigue in arm B. One treatment-related death (retroperitoneal hemorrhage) was seen in arm A. FACT-P and PPI scores did not significantly change in either arm. No correlation between BTM and PFS was seen in either arm.
Although limited by small numbers, this randomized study showed that the combination of VEGFR and Src targeted therapy did not result in improved efficacy and may be associated with a worse outcome than VEGFR targeted therapy alone in patients with CRPC.
Cediranib; Dasatinib; Castration resistant prostate cancer; Quality of life; Bone turnover marker
Arsenic trioxide (ATO) is an inorganic arsenic derivative that is highly effective against PML-RARα-positive leukemia but much less against other hematological malignancies. We synthesized an organic arsenic derivative (OAD), S-dimethylarsino-thiosuccinic acid (MER1), which offers a superior toxicity profile and comparable in vitro activity relative to ATO. In Swiss Webster mice, maximally-tolerated cumulative dose of MER1 when given IV for 5 days was 100 mg/kg/d. We demonstrated that MER1 induced apoptosis and dose- and time-dependent inhibition of survival and growth in a panel of myeloid leukemia cell lines. Unlike ATO, this activity was independent of PML-RARα status and was not associated with induction of myeloid maturation. In NB4 and HL60 cells, MER1 and ATO induced caspase activation and dissipation of mitochondrial transmembrane potential. At the same time, MER1 induced generation of reactive oxygen species (ROS) and cell cycle arrest in G2/M phase and proved to be more potent than ATO at inducing apoptosis. ROS generation and intracellular glutathione levels were key modulators of MER1-induced cytotoxicity as evidenced by abrogation of apoptosis in myeloid leukemia cell lines pretreated with the disulfide bond-reducing agent dithiothreitol or the radical scavenger N-acetyl-L-cysteine. Collectively, these data indicate that MER1 induces apoptosis in PML-RARα-positive and -negative myeloid leukemia cells by enhancing oxidative stress. This agent, therefore, combines low in vivo toxicity with formidable in vitro pro-apoptotic ROS-mediated activity, and may represent a novel OAD suitable for clinical development against a variety of hematological malignancies.
MER1; Organic arsenic derivatives; PML-RARα; Acute myeloid leukemia
Background This trial evaluated the maximum tolerated dose (MTD), safety, pharmacokinetics, and activity of volasertib, a selective Polo-like kinase 1 inhibitor that induces mitotic arrest and apoptosis, combined with cisplatin or carboplatin in patients with advanced/metastatic solid tumors (NCT00969761; 1230.6). Methods Sequential patient cohorts (3 + 3 dose-escalation design) received a single infusion of volasertib (100–350 mg) with cisplatin (60–100 mg/m2) or carboplatin (area under the concentration versus time curve [AUC]4–AUC6) on day 1 every 3 weeks for up to six cycles. Sixty-one patients received volasertib/cisplatin (n = 30) or volasertib/carboplatin (n = 31) for a median of 3.5 (range, 1–6) and 2.0 (range, 1–6) treatment cycles, respectively. Results The most common cycle 1 dose-limiting toxicities (DLTs) were thrombocytopenia, neutropenia and fatigue. MTDs (based on cycle 1 DLTs) were determined to be volasertib 300 mg plus cisplatin 100 mg/m2 and volasertib 300 mg plus carboplatin AUC6. Co-administration did not affect the pharmacokinetics of each drug. Partial responses were observed in two patients in each arm. Stable disease was achieved in 11 and six patients treated with volasertib/cisplatin and volasertib/carboplatin, respectively. Conclusions Volasertib plus cisplatin or carboplatin at full single-agent doses was generally manageable and demonstrated activity in heavily pretreated patients with advanced solid tumors.
Electronic supplementary material
The online version of this article (doi:10.1007/s10637-015-0223-9) contains supplementary material, which is available to authorized users.
Polo-like kinase inhibitor; Solid tumors; Phase I trial; Volasertib; Platinum therapy
Purpose Ixazomib is an investigational proteasome inhibitor with demonstrated antitumor activity in xenograft models of multiple myeloma (MM), lymphoma, and solid tumors. This open-label, phase 1 study investigated intravenous (IV) ixazomib, in adult patients with advanced non-hematologic malignancies. Methods Patients received IV ixazomib twice-weekly for up to twelve 21-day cycles. The 0.125 mg/m2 starting dose was doubled (one patient/dose) until 1.0 mg/m2 based on dose-limiting toxicities (DLTs) in cycle 1. This was followed by 3 + 3 dose-escalation and expansion at the maximum tolerated dose (MTD). Primary objectives included safety and MTD assessment. Secondary objectives included assessment of pharmacokinetics, pharmacodynamics, and disease response. Results Ixazomib was escalated from 0.125 to 2.34 mg/m2 to determine the MTD (n = 23); patients were then enrolled to MTD expansion (n = 73) and pharmacodynamic (n = 20) cohorts. Five patients experienced DLTs (1.0 and 1.76 mg/m2: grade 3 pruritic rash; 2.34 mg/m2: grade 3 and 4 thrombocytopenia, and grade 3 acute renal failure); thus, the MTD was 1.76 mg/m2. Drug-related grade ≥3 adverse events (AEs) included thrombocytopenia (23 %), skin and subcutaneous (SC) tissue disorders (16 %), and fatigue (9 %). Among 92 evaluable patients, one (head and neck cancer) had a partial response and 30 had stable disease. Ixazomib terminal half-life was 3.8–7.2 days; plasma exposures increased dose-proportionally and drug was distributed to tumors. Inhibition of whole-blood 20S proteasome activity and upregulation of ATF-3 in tumor biopsies demonstrated target engagement. Conclusions In patients with solid tumors, ixazomib was associated with a manageable safety profile, limited antitumor activity, and evidence of downstream proteasome inhibition effects.
Electronic supplementary material
The online version of this article (doi:10.1007/s10637-015-0230-x) contains supplementary material, which is available to authorized users.
20S proteasome; Activating transcription factor 3; Ixazomib; Non-hematologic malignancies; Phase 1 clinical trial (4–6)
2-methoxyestradiol (2ME2) is an estradiol-17β metabolite with antiproliferative and antiangiogenic activities. ENMD-1198 is an analog of 2ME2 which was developed to decrease the metabolism and increase both the bioavailability and antitumor activities of the parent molecule. This first-in-human phase I study evaluated the tolerability, pharmacokinetics and preliminary evidence of activity of ENMD-1198 in advanced cancer patients.
Eligible patients received ENMD-1198 orally once daily in Part A (standard 3+3 dose escalation design), or in Part B (accelerated dose escalation design). Cycle 1 consisted of 28 days daily dosing followed by a 14-(Part A) or 7-(Part B) day observation period, then continuously in 28 day cycles thereafter.
A total of 29 patients were enrolled in 12 dose cohorts (5 to 550 mg/m2/d). The most common drug-related toxicities were Grade 1/2 fatigue (55%), nausea and vomiting (37%), and constipation (34%). Two DLTs (Grade 4 neutropenia) occurred at 550 mg/m2/day, and 425 mg/m2/d was declared the maximum tolerated dose. ENMD-1198 was absorbed rapidly with a Tmax of 1–2 h. Exposure to ENMD-1198 (Cmax and AUC0–24hr) increased linearly with dose. The mean terminal half-life was 15 h. A 3-fold accumulation was found after multiple doses. Five patients achieved stabilization of disease for at least 2 cycles, three of whom (with neuroendocrine carcinoma of pancreas, prostate cancer and ovarian cancer) demonstrated prolonged stabilization ranging from 8–24.5 cycles.
ENMD-1198 is well-tolerated with a pharmacokinetic exposure profile compatible with once daily dosing. The recommended phase II dose of ENMD-1198 is 425 mg/m2/d. Early evidence of prolonged disease stabilization in pre-treated patients suggests ENMD-1198 is worthy of additional investigation.
ENMD-1198; Phase I; Pharmacokinetics
Sorafenib, an inhibitor of B-raf, VEGFR2, and PDGFR-β, has activity against pancreatic cancer in preclinical models. In a phase I trial of gemcitabine plus sorafenib, 57% of pancreatic cancer patients achieved stable disease.
Patients and methods
We conducted a multi-center phase II trial of sorafenib plus gemcitabine in chemo-naïve patients with histologicallyconfirmed, advanced pancreatic cancer. Patients received sorafenib 400 mg twice daily and gemcitabine 1,000 mg/m2 on days 1, 8 and 15 of a 28 day cycle.
Seventeen patients enrolled at 4 centers; 13 were evaluable for response. There were no objective responses; 18% had stable disease. Median overall survival was 4.0 months (95% CI: 3.4, 5.9); median progression-free survival was 3.2 months (95% CI: 1.6, 3.6). Grade 3/4 toxicities included thrombosis in 18% of patients, dehydration or hand-foot syndrome in 12%, and hypertension or gastrointestinal bleeding in 6%.
Gemcitabine plus sorafenib is inactive in advanced pancreatic cancer.
Pancreatic cancer; Phase II trial; Gemcitabine; Sorafenib
Treatment options for metastatic colorectal cancer (CRC) are limited after a fluoropyrimi-dine, oxaliplatin and irinotecan; novel agents need to be explored in this setting. Dasatinib, an oral inhibitor of Src family kinases, inhibits proliferation in CRC cell lines and has antitumor activity in CRC xenograft models.
Patients and methods
We conducted a multi-center phase II trial of dasatinib in unresectable, previously-treated metastatic CRC patients. No more than 2 prior chemotherapy regimens were permitted, which must have contained a fluoropyrimidine, oxaliplatin and irinotecan. The primary endpoint was progression-free survival (PFS) at 4 months. The Simon two-stage design required that at least 5 of the first 19 patients be progression-free at 4 months to expand to a second stage.
Nineteen patients enrolled at 9 centers. The study was terminated after the first stage due to lack of efficacy. There were no objective responses; 1 patient (5%) had stable disease for 7.3 months. The PFS rate at 4 months was 5.3% (90% CI: 0.3, 22.6). Median PFS was 1.6 months (90% CI: 1.4, 1.8). Median overall survival was 5.1 months (90% CI: 2.4, 6.3). Grade 3/4 toxicities included fatigue in 16% of patients, and anemia, anorexia, nausea/vomiting and dyspnea in 11%.
Dasatinib is inactive as a single agent in previously treated metastatic CRC patients.
Colorectal cancer; Phase II trial; Dasatinib
The primary objective of this phase II trial was to evaluate the efficacy and tolerability of vorinostat and bortezomib as third-line therapy in advanced non-small cell lung cancer (NSCLC) patients.
Eligibility criteria included recurrent/metastatic NSCLC, having received 2 prior systemic regimens, and performance status 0–2. Patients took vorinostat 400 mg PO daily days 1–14 and bortezomib 1.3 mg/m2 IV day 1, 4, 8 and 11 in a 21-day cycle. Primary endpoint was 3-month progression free survival (3m-PFS), with a goal of at least 40 % of patients being free of progression at that time point. This study followed a two-stage minimax design.
Eighteen patients were enrolled in the first stage. All patients had two prior lines of treatment. Patients received a median of two treatment cycles (range: 1–6) on study. There were no anti-tumor responses; stable disease was observed in 5 patients (27.8 %). Median PFS was 1.5 months, 3m-PFS rate 11.1 %, and median overall survival 4.7 months. The most common grade 3/4 toxicities were thrombocytopenia and fatigue. Two patients who had baseline taxane-related grade 1 peripheral neuropathy developed grade 3 neuropathy. The study was closed at its first interim analysis for lack of efficacy.
Bortezomib and vorinostat displayed minimal anti-tumor activity as third-line therapy in NSCLC. We do not recommend this regimen for further investigation in unselected patients.
Non-small cell lung cancer; Vorinostat; Bortezomib; Third-line
Preclinical and early clinical data support the use of Vascular Epithelial Growth Factor (VEGF)-targeted therapy with trastuzumab in Human Epidermal Receptor 2 (HER2) positive breast cancer. Adding bevacizumab to a taxane (docetaxel or paclitaxel) improves progression free survival (PFS) of metastatic breast cancer (MBC) patients.
We evaluated the efficacy and feasibility of combining bevacizumab with trastuzumab and docetaxel in patients with HER2- positive MBC who received 0–1 prior chemotherapy regimens for metastatic disease. The primary end point was PFS.
Materials and Methods
Eligible patients received bevacizumab (15 mg/kg), trastuzumab (8 mg/kg loading dose followed by 6 mg/kg), and docetaxel (100 mg/m2 initially, later amended to 75 mg/m2) every three weeks for six cycles and then were allowed to receive bevacizumab and trastuzumab alone.
Thirteen (50 %) of 26 patients enrolled completed all 6 cycles of bevacizumab, trastuzumab and docetaxel and went on to receive bevacizumab and trastuzumab alone (median: 11 cycles). The most common grade 3 or 4 toxicities include: neutropenia (8 %), septic death (4 %), infection not associated with neutropenia (15 %), fatigue (27 %), mylagia and/or arthraligia (20 %), and hand-foot syndrome (8 %). One patient (4 %) and six patients (23 %) developed grade 3 and grade 2 hypertension, respectively. Two (8 %) patients had transient grade 2 drop in Left Ventricular Ejection Fraction (LVEF) with full recovery later. The median progression free survival (PFS) was 14.3 months (95 % CI: 9.3–35 months), the objective response rate (ORR), defined as the best response of complete response (CR) or partial response (PR) was (12/26) 46 %. The clinical benefit rate (CBR), defined as the best response of CR or PR or stable disease (SD) for at least 24 weeks, was (18/26) 69 % (95 % CI: 48–86 %).
The combination of bevacizumab, trastuzumab and docetaxel is well tolerated and is clinically active in patients with HER2-positive MBC, with response rate and PFS comparable to previous reports utilizing higher dose of docetaxel (100 mg/m2). Recent randomized trials did not demonstrate additional overall survival (OS) benefit of adding bevacizumab to trastuzumab and docetaxel despite an improvement in PFS. Identification of predictive biomarkers and careful patient selection should be incorporated in further investigation of anti-VEGF in breast cancer.
Bevacizumab; Trastuzumab; Docetaxel; Metastatic breast cancer; HER2