bluuebunny/crossref_metadata_2025 huggingface dataset:
Biomarker and in vitro chemoresistance profiles of undifferentiated ovarian cancers
Authors: Chan J. K. , Kapp D. S. , Mechetner E. , Yu I.
Published: March 2020

2532

Background: To determine the biomarker expression and drug resistance patterns of undifferentiated ovarian cancers. Methods: Biomarker expression was determined by immunohistochemistry. In vitro drug resistance profiles were analyzed by assays exposing tumors to suprapharmacologic doses of chemotherapy. Results: Of 177 ovarian cancer specimens, 63 were classified as undifferentiated tumors and 114 well-differentiated cancers were used for comparison. Of the undifferentiated tumors, 46.7% were primary cancers and the remainder were recurrent cancers. Most of the well-differentiated tumors were obtained from primary (82%) vs. recurrent disease specimens. The average DNA index and S-phase fraction were significantly higher in the undifferentiated vs. well-differentiated tumors (1.42 vs. 1.23, p=0.025 for DNA index; 1.69 vs. 3.06, p<0.0001 for S phase fraction). In addition, the percent of tumors with p53 mutations was also higher in the undifferentiated compared to the well-differentiated tumors (47.8% vs. 17.8%; p=0.005). The mean percent cell inhibition was significantly lower in the undifferentiated tumors compared to well-differentiated cancers after exposure to etoposide (54%±21 vs. 80%±18; p=0.0002), doxorubicin (59%±28 vs. 80.0%±21; p=0.07), and topotecan (61.7%±20 vs. 71%±21; p=0.015). Compared to well-differentiated tumors, undifferentiated tumors tended to be more resistant to etoposide (40% vs. 11%), doxorubicin (22% vs. 9%), and topotecan (19% vs. 16%). However, the drug resistance patterns after exposure to taxanes (paclitaxel and taxotere) and platinums (carboplatin and cisplatin) were similar. Conclusions: Undifferentiated tumors of the ovary have a significantly different biomarker expression and drug resistance profiles compared to well-differentiated tumors. Given that undifferentiated cancers provide a treatment challenge for the clinician, this data can provide additional prognostic and therapeutic information, and warrants further investigation.

No significant financial relationships to disclose.
Positron-emission tomography reveals early flare in uptake of FLT in tumors following chemotherapy with gemcitabine
Authors: McArthur G. A. , Hicks R. M. , Shalinsky D. R. , Binns D. , O’Kane C. , Hogg A. , Fisher R. , McCarthy T. J. , Anderes K. A.
Published: March 2020

2537

Background: Strategies to monitor molecular & cellular responses to novel cell cycle targeting agents are vital to provide proof of their mechanism & biological activity. In developing biomarkers for the novel chk1 inhibitor, PF-477736, we demonstrated that gemcitabine chemotherapy induced a significant increase, or flare, in uptake of the PET tracer, 3’-deoxy-3’flurothymidine (FLT), into tumor xenografts 24 h after dosing (Proc ASCO 24:A3045, 2006). We postulated that an early flare in FLT may also occur following gemcitabine therapy in human tumors. Methods: Eligible patients had at least 1 malignant lesion identified by CT scan outside of a previous radiation field. Patients received a baseline FLT-PET scan day-1 to -4 relative to 1st dose of gemcitabine at 1,000 mg/m2, and a post dose FLT- PET scan 22–26 h after gemcitabine. Endpoints were FLT uptake as assessed by: SUV; a qualitative scoring system; and tumor-to-background (T:B) ratios using liver, mediastinum and bone marrow as references. Results: Six of 8 planned patients with 14 index lesions have been accrued in this pilot study. 4/6 patients demonstrated increased uptake of FLT as defined by >50% increase in SUV or T:B ratio in at least 1 lesion. Analysing all index lesions showed an increase in FLT-uptake post gemcitabine as assessed by a 4 point qualitative scoring system from 1.6±0.2 to 2.7±0.1 (p=0.01) or T:B 1.1±0.2 to 2.0±0.3 (p<0.01) using liver as a reference. Interestingly in contrast to increased uptake in tumors, uptake of FLT in bone marrow was reduced from an SUV of 6.4±0.6 to 3.4±0.7 (p<0.01) following gemcitabine. Conclusion: Following treatment with gemcitabine there was an early flare in uptake of FLT into many tumors. In contrast, uptake in bone marrow was reduced. FLT-PET appears to be a promising tool to monitor the cell cycle response of both tumor and bone marrow to cytotoxic chemotherapy.

No significant financial relationships to disclose.
A phase I/II, pharmacokinetic (PK) and pharmacogenomic (PG) study of weekly irinotecan (CPT-11) therapy for elderly patients with advanced non-small cell lung cancer
Authors: Isobe H. , Yamamoto N. , Kunikane H. , Masuda N. , Eguchi K. , Shibuya M. , Takeda Y. , Ogura T. , Yokoyama A. , Harada M. , Watanabe K.
Published: March 2020

2539

Background: CPT-11 is commonly used to treat lung cancer, but there is little evidence about its efficacy in elderly patients. The aim of this study was to determine the recommended dose (RD) of CPT-11 for weekly administration to elderly patients, and to assess its efficacy and safety. In addition, a PK and PG study was performed to investigate the influence on the clinical outcome. Methods: CPT-11 was infused intravenously on Days 1 and 8 (every 21 days). In the phase I study, the dosage of CPT-11 was escalated from 60 (Level 1) to 80 (Level 2) and 100 mg/m2 (Level 3). PK of CPT-11 and SN-38, and UGT1A1 polymorphism were analyzed during the first treatment cycle in the phase II study. Results: In the phase I study, 12 patients were enrolled (level 1/2/3=6/3/3) and the RD was determined to be 100 mg/m2. The 37 patients in phase II had the following characteristics: male/female=25/12, median age=77 (71–88), IIIB/IV=10/27, PS 0/1=12/25. The overall response rate and the disease control rate (PR+SD) was 8% and 73%, respectively. The median survival time was 441 days and the 1-year survival rate was 54.0%. Grade 3/4 neutropenia and diarrhea occurred in 27% and 8%, respectively. The AUCs for both CPT-11 and SN-38 were significantly correlated with neutropenia (P=0.0095, P=0.0004). Both the UGT1A1*6 and UGT1A1*28 genotypes were significantly correlated with the AUC ratio, leukopenia, and neutropenia ( Table ). Conclusion: CPT-11 monotherapy is considered to be effective for non-small cell lung cancer in elderly patients because good survival with tolerable adverse events were achieved. The UGT1A1*6 and UGT1A1*28 genotypes might both influence the toxicity of irinotecan in Asians.

[Table: see text]

[Table: see text]
Relationship between persistent neurotoxicity and long-term platinum exposure after treatment with cisplatin
Authors: Brouwers E. E. , Huitema A. D. , Boogerd W. , Beijnen J. H. , Schellens J. H.
Published: March 2020

2546

Background: We aimed to assess relationships between the severity of persistent neuropathy and long-term platinum exposure in patients previously treated with cisplatin. Methods: Twenty patients, treated with a cisplatin containing regimen 18 to 75 months before participating in this study, were included. Sensory nerve function in hands and feet was evaluated using vibration threshold (VT) determination. Platinum levels in plasma and plasma ultrafiltrate were assessed using inductively coupled plasma mass spectrometry (ICP- MS). Possible factors affecting sensory nerve function or platinum retention were collected, including cumulative dose, follow-up time, route of administration, renal function, glutathione S-transferase (GST) genotypes, co-administration of sodium thiosulfate (STS with intra-arterial (i.a.) cisplatin), and co-morbidity (alcoholism and diabetes). Results were evaluated using non linear mixed effects modelling. Results: Patients (9 testis, 8 head-neck, 1 NSCLC, 1 SCLC, and 1 yolk sac) were treated with a cumulative dose of 300–600 mg·m-2. Five patients received STS. Platinum plasma concentrations ranged between 142.4–1154 ng·L-1of which on average14.8% was recovered in ultrafiltrate. Platinum levels decreased with a half-life of 21.7 months and were related to the cumulative dose. Platinum levels were reduced by 60% with i.a. cisplatin and co-administration of STS (p=0.002). The hand-VT decreased with time (t1/2=19.9 months) and was related to cumulative dose and to alcohol use (p=0.06). Moreover, the half-life of recovery of the hand-VT was related to the elimination half-life of platinum, albeit non-significant. In contrast, the feet-VT did not improve over time and did not show an association with cumulative dose or any of the other factors. GST genotypes and renal function were not related to VT and platinum levels. Conclusions: Our data suggest that plasma platinum levels are related to follow-up time, cumulative dose, and STS use. The data show that neuropathy in the feet might be irreversible in contrast to the hand-VT, which was also related to cumulative dose and alcohol use. Whether recovery of neuropathy was related to platinum elimination remains to be established.

No significant financial relationships to disclose.
A phase I trial of E7974 administered on days 1 and 15 of a 28-day cycle in patients with solid malignancies
Authors: Madajewicz S. , Zojwalla N. J. , Lucarelli A. G. , Hentschel P. , Giardelli J. , Schuck E. L. , Krivelevich I. , Wong B. Y. , Vogelzang N. J. , Sharma S.
Published: March 2020

2550

Background: E7974 is a synthetic hemiasterlin analogue exhibiting binding to a and β tubulin. It induces disruption of spindle formation and mitotic arrest characteristic of anti-tubulin cancer drugs. Unlike taxanes and vincas, E7974 is a poor substrate for the PgP drug efflux pump, potentially overcoming this common mechanism of drug resistance. E7974 demonstrates broad anti-tumor activity against a variety of human tumor xenografts. Methods: An accelerated phase I dose escalation design was used to determine the maximum tolerated dose (MTD) and pharmacokinetic (PK) profile of E7974 administered IV over 2–5 minutes on Days 1 and 15 of a 28-day cycle. Results: Seventeen patients (14 male, 3 female) with a median age of 59 yrs. (range: 42–77 yrs.) were treated at doses of 0.18 mg/m2, 0.25 mg/m2, 0.31 mg/m2, and 0.39 mg/m2. Patients with colorectal (6), esophageal (3), prostate (2), urothelial (2), NSCLC (2), and other (2) cancers were enrolled. At the 0.39 mg/m2 dose level, one patient experienced grade 3 neutropenia and 2 patients experienced grade 4 neutropenia. The 0.31 mg/m2 dose was declared the MTD. Additional drug related toxicities (grade 1–2) included fatigue (8 pts.), constipation (4 pts), neuropathy (3 pts.), diarrhea (2 pts.), flushing (2 pts.) and myalgia (1 pt.). One patient with esophageal cancer had a partial response at the 0.39 mg/m2 dose level and one patient with prostate cancer had >50% decline in PSA and significant clinical benefit for >4 months at the 0.31 mg/m2 dose level. Stable disease was seen in two patients, one with esophageal cancer (8 cycles) and one with colorectal cancer (4 cycles). The PK profile of E7974 was characterized by moderate to large distribution (Vss = 55 - 187 L), slow clearance (CL = 1.99 - 8.77 L/hr) and moderate to slow elimination (t1/2 = 11.9 - 31.6 hr). Approximately 26 - 85% of the administered dose of E7974 was recovered unchanged in the urine 48 hours post-dose. Conclusions: The recommended phase 2 dose of E7974 on days 1 and 15 of a 28-day schedule is 0.31mg/m2. Observed toxicities were manageable and reversible.

No significant financial relationships to disclose.
The 2-13C-5-fluorouracil breath test (FUBT) as a novel, rapid method for assessment of dihydropyrimidine dehydrogenase (DPD) activity in cancer patients: Initial characterization and comparison to the 2-13C-uracil breath test (UraBT)
Authors: Fourie J. , Mattison L. K. , Wood T. E. , Posey J. A. , Modak A. , Diasio R. B.
Published: March 2020

2551

Background: The UraBT is currently in development as a phenotypic test to screen for DPD deficiency. Following an oral dose of 2-13C-uracil, the UraBT shows a significant relationship between breath 13CO2 metabolite formation and plasma 2-13C-uracil and 2-13C-dihydrouracil pharmacokinetics. We herein describe a novel, potentially more clinically relevant test in which a small oral dose of 2-13C-5-fluorouracil (5-FU) is administered, followed by assessment of breath 13CO2 metabolite formation as previously described for the UraBT. We hypothesize that the FUBT can rapidly assess interindividual variability in 5-FU catabolism and predisposition to 5-FU toxicity. Methods: Over two sessions separated by a seven day washout, a single dose (6mg/kg, p.o.) of 2-13C-uracil or 2-13C-5-FU was administered to patients with stage III-IV colorectal cancer (n = 4). Subsequent to drug administration, in each session, 13CO2 catabolite formation was quantified in the breath over eight hours. In a separate investigation over two sessions separated by a seven day washout, a single dose (3mg/kg, p.o.) of 2-13C-uracil or 213C-5-FU was administered to colorectal cancer patients with previously documented severe (n=2) or moderate (n=2) 5-FU dose-related hematological/gastrointestinal toxicity. Following drug administration 13CO2 catabolite formation was quantified over eight hours. 13CO2 concentration was expressed as Delta Over Baseline (DOB) in all sessions. Results: Compared to the UraBT, the FUBT showed an increased Cmax (50.7 ± 6.6 DOB/mg vs. 36.8 ± 7.8 DOB/mg; mean ± SD) and decreased Tmax (25 ± 4 min vs. 45 ± 6 min) for 13CO2 formation (p<0.05). The FUBT was able to distinguish patients with previously reported severe and moderate 5- FU toxicity, with 13CO2 Cmax values of 35.5 ± 9.5 DOB/mg (mean ± SD) and 59.8 ± 7.3 DOB/mg, respectively. Importantly, FUBT Cmax values positively correlated with DPD activity (rs=1.00, p<0.01). Conclusions: These data lend support to further development of the FUBT as a rapid and informative test to assess DPD activity and to predict susceptibility to severe dose-related 5-FU toxicity. [CA116964]

No significant financial relationships to disclose.
Treatment of anthracycline extravasation with dexrazoxane: Pharmacokinetics and update on efficacy and safety from three multicenter trials
Authors: Giacone G. , Handskemager L. , Mouridsen H. , Tjornelund J. , Langer S. , Buter J. , Rasmussen A. , Buhl P. , Dahlstrom K. , Grundtvig P.
Published: March 2020

2555

Background: Dexrazoxane prevented tissue necrosis in 98% of patients (pts) with biopsy proven anthracycline extravasation (AEV) in two international multicenter studies, TT01 and TT02 (Mouridsen HT et al Ann Onc Advance Access Dec 21, 2006). However, the pharmacokinetics (PK) of IV dexrazoxane in the three-day schedule is not established. Study TT04 was initiated to investigate PK. Patients and methods: TT04 is a prospective, open-label, single-arm, multicenter studies in pts with AEV. Consecutive pts with AEV are treated with a three-day schedule of IV dexrazoxane (1,000, 1,000, and 500 mg/m2) starting within 6 hr of AEV. Primary objective: Establish PK of IV dexrazoxane in the three-day schedule. Secondary objectives: obtaining additional efficacy and safety data. Plasma samples at 0, 1, 2, 4 and 24 hr day 1–3 are analyzed by HPLC-MS. PK parameters were calculated by a non compartmental method. TT01 and TT02 were open-label, single-arm, multicenter studies enrolling pts with biopsy proven AEV from 24 EU centers. Primary objective was to avoid tissue necrosis leading to surgery. Secondary objectives were to minimize delay of planned chemotherapy, reduce hospitalization, and avoid long term sequelae. Results: Six pts have entered the PK study. The average elimination was T½ ± SD of 127 ± 23, 144 ± 21, and 107 ± 29 min, day 1, 2 and 3, respectively. Pre-dose concentrations day 2 and 3 are = LOQ. Average AUC 0-t ± SD are 193 ± 93 (t= 24 hr), 196 ± 101 (t= 24 hr), and 46 ± 24 μg hr/ml (t= 4 hr), on day 1, 2 and 3, respectively. Cumulative data from the 3 studies: Surgery was avoided in 59/60 pts (98.3%). No delay in planned chemotherapy in 71%. 41% were hospitalized (median 3 days) due to the EV or its treatment. Mild pain (19%) and mild sensory disturbances (17%) were the most frequent sequelae: Reversible CTC grade 3–4 leucopenia/neutropenia in 45%, thrombocytopenia in 21% of the pts. Conclusion: There was no accumulation of dexrazoxane during the three-day schedule. Dexrazoxane was well tolerated and highly effective against anthracycline extravasation. Updated results will be presented.

No significant financial relationships to disclose.
Pharmacokinetic results of a phase I trial of sorafenib (S) in combination with dacarbazine (DTIC) in patients with advanced metastatic melanoma or other solid tumors
Authors: Brendel E. , Zafarana E. , Figuerola C. , Ludwig M. , Lathia C. , Burk K. , Robert C. , Soria J. C. , Armand J. P.
Published: March 2020

2563

Background: Sorafenib (S) is a multikinase inhibitor that prevents tumor cell proliferation and angiogenesis via receptor tyrosine kinases, VEGFR-1, -2, -3 and PDGFR-a and -β, and the Raf/MEK/ERK pathway at the level of Raf kinase. Single-agent studies show S is well tolerated with manageable and reversible side effects, most commonly, diarrhea, rash, fatigue, and hand-foot skin (HFS) reaction. This phase I study assessed the safety and pharmacokinetics (PK) of the combination of S and DTIC. Methods: 23 patients (pts) received a fixed dose of DTIC (1,000 mg/m2 given every 3 wks) starting on Day 1 of cycle 1 (C1). S (400 mg bid) was given on days 2–21 in C1 and continuously thereafter. PK profiles of DTIC and 5-aminoimidazole-4-carboxamide (AIC; an inactive D metabolite that is formed in an equal proportion to the active moiety, diazomethane, that cannot be analytically measured) were obtained from day 1 of both C1 and C2 and PK profiles of S from Day 1 of C2. Results: 23 pts (M:F, 11:12; mean age 57±9 yrs) were treated with S and DTIC. Of these pts, 15 were valid for PK analysis. Following simultaneous administration of S, mean AUC and Cmax of DTIC were moderately reduced by 23% and 16%, while mean AUC and Cmax of AIC were increased by 41% and 45%, respectively. Mean AUC (0–12)ss and Cmax,ss of S were 28.3 mg*h/L (84%) and 3.67 mg/L (77%), respectively, upon concomitant dosing of S and DTIC. These sorafenib exposures are within the range of exposures observed in phase I studies. Six pts had an increase of either Cmax or AUC of AIC of at least 70%, and in 4 of the 6 pts, this increase was correlated with grade 4 thrombocytopenia. Conclusions: The combination of S and DTIC resulted in moderate decreases of DTIC exposure; however, more pronounced increases in AIC exposure were observed. In patients with a distinct increase (=70%) in AIC, a correlation between exposure and toxicity cannot be excluded, however, all toxicities were manageable.

No significant financial relationships to disclose.
A simulation study to define the number of patients necessary to meet primary pharmacokinetic (pk) aims of phase I oncology trials
Authors: Adamson P. C. , Zhao H. , Sievert A. , Troxel A. , Aplenc R.
Published: March 2020

2579

Introduction: The primary pharmacokinetic parameters defined in oncology phase I trials include estimates of drug clearance and determining the relationship between dose and drug exposure as measured by AUC. The numbers of patients needed for reliable estimates of these parameters, however, has not been defined. We hypothesized that a threshold number of patients existed above which meaningful improvement in such estimates would not occur. Methods: We identified 28 English language adult phase 1 oncology publications (2004-2006) from which individual patient dose and AUC data could be extracted. Analyses of clearance precision were performed in PASS 2000. Simulations were performed by determining a distribution of r2 coefficients for the regression of AUC on dose for each trial, for sample sizes of 2 to n-1, where n was the total patient number studied. Median values for the simulated r2 and a 90% confidence interval (CI) were obtained for every simulation. A stability boundary of 0.1 around the simulated r2 value was calculated. A 90% confidence interval around the observed r2 value was also bootstrapped. An r2 value was considered stable when the simulated r2 CI fell within the stability boundary for all subsequent sample sizes. Results: Analyses of the precision of mean clearance estimates over a range of confidence intervals demonstrated that the incremental gain in clearance precision estimates was marginal beyond the study of 8 to 12 patients. Linearity simulations of AUC vs dose demonstrated the median (range) of patients needed to determine a stable r2 estimate was 7 (4 - 16), with a mean (±SD) of 7.8 ± 3.2. Conclusions: These simulations show that, in general, only 8–12 patients are needed to meet the primary PK objectives of phase I oncology trials. While such modest sample sizes are not sufficient to define pharmacokinetic-dynamic-genetic relationships, such relationships rarely emerge from phase I trials. Our simulations indicate that the number of patients needed to meet PK objectives may be more modest than previously anticipated, and should be readily achievable with voluntary participation in the PK component of oncology phase 1 trials.

No significant financial relationships to disclose.
Phase I study of bi-weekly pemetrexed (P) plus cisplatin (C) in patients with advanced cancer
Authors: Lopez-Martin A. , Paz-Ares L. , Calvo E. , Castellano D. , Valverde C. , Neciosup S. , Vilar E. , San Antonio B. , Garcia-Ribas I. , Cortes-Funes H. , Bellmunt J.
Published: March 2020

2580

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.
Phase I trial of huA33 antibody plus 5-fluorouracil (5FU), leucovorin, and oxaliplatin in patients with metastatic colorectal cancer [LUD2003–005]
Authors: Renner C. , Ritter G. , Pan L. , Venkatramin E. , Hoffman E. W. , Venhaus R. , Old L. , Knuth A. , Jäger E. , Pfreundschuh M.
Published: March 2020

3022

Background: The selective targeting of tumors with monoclonal antibodies (mAb) has emerged as a new therapeutic approach in cancer therapy with the A33 glycoprotein being a promising target in colorectal cancer. Specific tumor localization and low toxicity of a humanised A33 specific mAb (huA33) has previously been demonstrated in patients with colorectal carcinoma. In the present study, we determined the safety and efficacy of the combination of huA33 and 5FU plus leucovorin and oxaliplatin (FOLFOX-4) in patients with metastatic colorectal cancer. Methods: Patients had to present with metastatic colorectal cancer with an expected survival of at least 4 months and no more than 2 different pre-treatment regimens. Patients were excluded if they had previously received oxaliplatin or huA33 mAb. Eligible patients received huA33 (10 mg/m2) by iv infusion weekly for 12 weeks (cycle 1). On study day 15, standard FOLFOX-4 chemotherapy was administered every 2 weeks for 10 weeks. Responding patients received a second cycle of weekly huA33 (10 mg/m2) and biweekly FOLFOX-4 chemotherapy. Results: A total of 19 patients (11 female, 8 male) with a median age of 60 years entered the study. 5 patients had received prior chemotherapy, 2 radiation therapy and 18 surgery. Toxicities observed were as expected for FOLFOX-4 treatment alone with hematological side effects to be most prominent and included (only G3 and G4) 1 anemia and 10 neutropenias. The addition of huA33 to FOLFOX-4 did not change the pattern of known non-hematological toxicities with a low rate (14%) of huA33 mAb associated allergic reactions. One sudden death occurred at cycle five that was neither therapy nor disease related. Within the 16 patients currently available for response assessment, the overall response rate was 38% with 1 CR, 5 PR and 5 disease stabilizations. Conclusion: The combination of FOLFOX-4 as standard chemotherapy for this cohort of patients in combination with the humanized A33 antibody did not increase toxicities and was well tolerated. The overall response rate of 38% is in the response range published so far for the FOLFOX-4 regimen in this setting and warrants further analysis in a larger cohort of patients.

[Table: see text]
Mesenchymal stem cells selectively engraft into tumor stroma and produce potent antitumor proteins in situ
Authors: Andreeff M. , Dembinski J. , Studeny M. , Ling X. , McQueen T. , Klopp A. , Marini F.
Published: March 2020

3025

Background: The formation of stroma is essential for tumor growth and involves complex interactions between malignant cells and non-tumor stromal cells. We have previously demonstrated that IV injected bone marrow derived mesenchymal stem cells (MSC) integrate into solid tumors as stromal elements (Cancer Res 62:3603, 2002; JNCI 96:1593, 2004). Methods: MSC were labeled by a fiber modified Ad vector expressing firefly luciferase (AdLux-F/RGD), injected into normal or tumor-bearing SCID mice, and biodistributed MSC-Lux were imaged utilizing the Xenogen IVIS system. Results: After IP injection, no hMSC-LUX were detected in normal animals after 7 days, while strong punctate regions of LUX-activity were observed in ovarian tumors. Tumor cells transduced with renilla luciferase constructs co- localized with firefly luciferase MSC. Next, we examined whether hMSC-producing interferon-beta (IFNβ-MSC) could inhibit the growth of metastatic tumors in the lungs of SCID mice. When injected IV (4 doses of 106 MSC/week) into SCID mice with pulmonary metastases of carcinomas or melanomas, tumor growth was significantly inhibited as compared with untreated or vector-control MSC controls (p= 0.007). IV injected IFNb-MSC prolonged the survival of mice bearing metastatic breast carcinomas (p=0.001). In an orthotopic, chemoresistant breast cancer model in syngeneic immunocompetent mice, MSC producing IFN-β completely abrograted tumor growth. Localized low-dose XRT to tumors significantly increased the number of tumor-resident MSC. Conclusions: The data suggest that systemically administered gene-modified MSC selectively engraft into the tumor microenvironment and remain resident as part of the tumor architecture. MSC-expressing IFN-β inhibit the growth of melanomas, gliomas, metastatic breast and ovarian cancers in vivo and prolong the survival of mice bearing established tumors. Clinical trials are in preparation.

No significant financial relationships to disclose.
Induction of apoptosis of myeloid leukemia with CSC17.1, a unique monoclonal antibody targeting CD45RA
Authors: Tesi R. J. , Tran H. , Christensen J. , Morales J. , Karimi M. , Sagy M. , Palath V.
Published: March 2020

3030

Background: Blast crisis from myeloid leukemia is may be responsive to chemotherapy, but a majority of patients die from their disease. Relapse may be due to persistence of cancer stem cells (CSC). A monoclonal antibody (mAb) that targets myeloid blast cells including the CSC without targeting the hematopoietic stem cell (HSC: CD34+90+) may be of value. CSC phenotype of CML-BC (CD34+38+123+45RA+) and AML (CD34+38–90-) have been defined. Method: We developed a biologically based mAb platform with 2 important steps after generating the mAb library: i) mAb must not bind the HSC (SS; safety screen); and ii) must bind the target cells (RxS; therapeutic screen). HSC for the SS were from G-CSF mobilized blood; cells for RxS was patient specimens of CML-BC and AML. After screens, the target was indentified, in vitro and in vivo functional assays are performed. Results: 5 of 400 mAb passed the SS and RxS. CSC17.1, an IgG2b isotype binding a unique, linear, 12 amino acid sequence of CD45RA has been selected. CML (Kasumi4), AML (Kasumi3 and KG1a), ALL (MOLT3) and NHL (Pfeiffer) cel lines express high levels of CD45RA. Five of 5 CML-BC and 3 of 3 AML patient specimens express CD45RA in high levels. Kausmi4 and Pfeiffer cell lines and patient specimens of CML-BC and AML undergo apoptosis in a dose and time dependent manner after exposure to CSC17.1 (>80% apoptosis at 1ug/ml@8h). KG1a is refractory to apoptosis despite high levels of target on the cell surface (15% apoptosis at 1ug/ml@8h). Normal T,B and NK cells express high levels of CD45RA, but do not undergo apoptosis or activation when exposed to CSC17.1. CSC17.1 causes capping and patching, but not internalization of CD45RA in cell lines and CD8+ normal cells. Commercially available antibodies to CD45RA do not inhibit binding of CSC17.1 to CD45RA, do not cause apoptosis, do not cause patching and capping, but do undergo internalization. In vivo murine models with cell lines and patient specimens of CML-BC and AML are underway. Conclusions: 1) CSC17.1 binds a previously undefined epitope of CD45RA that causes apoptosis of selected hematopoietic tumor cell lines and patient specimens of CML-BC and AML; 2) apoptosis, is a unique function of CSC17.1 compared to other mAb against CD45RA; 3) CML-BC and AML CSC include the CD45RA antigen suggesting CSC17.1 will target these cells.

No significant financial relationships to disclose.
Lung cancer-derived EGFR mutations affect responses to tyrosine kinase inhibitors, but not to monoclonal antibodies
Authors: Dechant M. , Peipp M. , Schneider-Merck T. , Beyer T. , Lammerts van Bueren J. J. , Bleeker W. K. , Parren P. W. , van de Winkel J. G. , Valerius T.
Published: March 2020

3044

Background: The epidermal growth factor receptor (EGFR) serves as a molecular target for novel cancer therapeutic approaches. Two groups of anti-EGFR agents are clinically most advanced: tyrosine kinase inhibitors (TKI) and EGFR antibodies. Recently, somatic mutations in the EGFR kinase domain were identified in tumors from lung cancer patients, which affected EGFR signaling and which correlated with responses to TKI therapy. Since interference with tumor cell signaling is also considered an important mechanism of action for therapeutic antibodies, we investigated the influence of these intracellular EGFR mutations on cell killing by EGFR antibodies, in comparison to TKI. Methods: For this purpose, we established an EGF-responsive, non-transformed cell line model for the three most common lung cancer-derived intracellular EGFR mutations L858R, G719S and delE746-A750. EGFR phosphorylation status was analyzed by Western Blots. MTT assays were performed to compare TKI gefitinib and erlotinib with antibodies C225 and 2F8 in their capacity to inhibit cell growth of wild type and mutated EGFR-transfectants. Impact of intracellular EGFR mutations on immune cell-mediated killing by EGFR antibodies was measured in classical 3 hours 51-chromium-release assays. Results: Mutated EGFR transfected cells were growth factor- responsive, and significantly more sensitive to both gefitinib and erlotinib than wild type (WT) EGFR expressing cells. However, anti-tumor effector functions of both EGFR-directed IgG1 antibodies—chimeric C225 and fully human 2F8—were not affected by the mutations. Conclusions: Intracellular mutations of EGFR may, therefore, be less relevant for EGFR antibodies than for TKI.

No significant financial relationships to disclose.
Agonist anti-GITR antibody induces CD8 T cell-mediated tumor rejection
Authors: Cohen A. D. , Diab A. , Perales M. A. , Duan F. , Jenq R. , Rizzuto G. , Hirschorn-Cymmerman D. , Merghoub T. , Wolchok J. D. , Houghton A. N.
Published: March 2020

3058

Background: Signaling through GITR (glucocorticoid-induced tumor necrosis factor receptor) can abrogate the suppressive effects of CD4+foxp3+ regulatory T cells and co-stimulate activated effector CD4+ and CD8+ T cells. We have previously shown that in vivo GITR ligation using the agonist anti-GITR mAb DTA-1 augments concomitant immunity and immunity generated by active immunization with self- tumor antigens. In the present study, we assessed the activity of anti-GITR mAb used alone, focusing on the effects of GITR ligation on CD8+ T cells during tumor growth. Methods: C57BL/6 mice were injected intradermally with B16 melanoma and received 1mg of DTA-1 or control rat IgG intraperitoneally on various days after tumor injection. In some experiments, naïve, CFSE-labeled pmel-1 CD8+ transgenic T cells (specific for the melanoma antigen gp10025–33 epitope) were transferred into naïve recipients 1 day prior to B16 inoculation. Results: DTA-1 treatment on days 0 and 4 led to tumor rejection in 20–30% and 50–60% of mice, respectively, compared with rejection in 0–5% of mice treated with control IgG (p<0.05 for both). Treatment at day 7 or later had no significant impact on tumor-free survival. The importance of CD8+ T cells in mediating DTA-1-induced tumor immunity was demonstrated by 4 findings: 1) in untreated mice, tumor-infiltrating CD8+ lymphocytes significantly upregulated GITR expression during tumor growth; 2) DTA-1-treated mice had greater CD8+ T cell infiltration into tumors than IgG-treated mice; 3) depletion of CD8+ cells completely abrogated the tumor protection provided by DTA-1; and 4) tumor-specific CD8+ cells proliferated more extensively, became more activated, and exhibited greater effector function following DTA-1 administration compared with control IgG. This was most dramatically seen within the tumor (compared with spleen or draining lymph node), suggesting that a major mechanism of tumor immunity induced by anti-GITR mAb may be overcoming impaired CD8+ T cell function within the tumor microenvironment. Conclusions: Ligating GITR using an agonist mAb can by itself augment tumor-specific CD8+ T cell responses and induce rejection of an aggressive, poorly immunogenic tumor. This strategy merits further consideration as an immune-modulating therapy for cancer.

No significant financial relationships to disclose.
The changing face of phase I protocols: A closer look at study requirements
Authors: Craft B. S. , Kurzrock R. , Herbst R. , Culotta K. , Stewart C. , Dorsey V. , Lippman S. , Gingher D. , Bekele N. , Karp D.
Published: March 2020

3061

Background: We have studied our recent experience in the MDACC Clinical Translational Research Center (CTRC), the Phase I Program, and the Dept. of Thoracic/Head & Neck Medical Oncology to compare the extent of regulatory and other requirements for current phase I and II cancer clinical trials. Methods: We developed a comprehensive database, together with a Microsoft Excel spreadsheet matrix to analyze the number and extent of diagnostic and therapeutic requirements for each protocol. We then examined the demands for pharmacokinetic (PK) sampling as well as electrocardiography (ECG) in the first cycle of a protocol as a surrogate for study complexity. Results: Since October, 2002, 250 protocols have been conducted in the CTRC; 54.6% were Phase I clinical trials. We reviewed 65 trials, approximately one quarter of the total. Of these, 48 were phase I trials carried out by the Phase I Program. For comparison, we identified 17 phase II trials managed by the Dept. of Thoracic/Head & Neck Medical Oncology during the same time period. In the phase I trials there were significantly more PKs (mean ± SE = 16.69 ± 1.93) than in the phase II trials (mean ± SE = 1.82 ± 1.17) (p<0.0001). Similarly, there were more ECGs in the phase I versus phase II trials (4.46 ± 1.18 vs. 1.41 ± 0.35; p=0.017). Conclusions: Pharmacokinetic collection and ECG monitoring in Phase I trials are complex and labor-intensive. In addition, they represent only a small portion of time-intensive requirements, with increasingly complicated correlates and monitoring (physical exams, imaging, etc.). Successful and accurate Phase I clinical trials require resources and commitment for research infrastructure considerably greater than later phase studies.

No significant financial relationships to disclose.
Dendritic cell therapy in glioblastoma multiforme
Authors: Nesselhut J. , Nesselhut T. , Chang R. , Marx D. , Brockmann W. , Wilke I. , Matthes C. , Lorenzen D. , Stücker W. , Peters H. , Lüke W.
Published: March 2020

3065

Background: Malignant brain tumors belong to the tumors with unfavorable prognosis. The most aggressive form, glioblastoma multiforme (GBM WHO grade IV glioma), is categorized as incurable with median survivals less than 12–18 months and 90–95% of patients surviving less than 2 years. Here we show that immunotherapy with monocyte-derived dendritic cells (MoDC) can induce a clinical response in advanced GMB, especially when combined with the non human pathogenic oncolytic virus NDV (New Castle Disease Virus). Methods: After isolating monocytes from peripheral blood of n=21 patients dendritic cells were generated ex vivo in the presence of recombinant cytokines (IL-4, GM-CSF) and 2,5% autologous serum. If tumor tissue was available the MoDC were primed on day 5 with tumor- lysate and co-cultured with poly:IC and IFN-alpha. The MoDC were harvested on day 7 of culture and administered to the patients, intradermally. In 5 patients NDV was added to the MoDC for one hour prior to administration. These patients received an infusion with NDV one day before vaccination. Results: We were able to induce a clinical response in 33% (n=7) of the treated patients. The median survival after onset of DC-therapy was 10 months. With respect to primary diagnosis the median survival was 19 months with 1- and 2-years survival rates of 81% and 14%, respectively. Improvement of the clinical response can be observed by combination of NDV. None of the 5 patients treated with this combination therapy died of the disease (9–19 months after primary diagnosis). Three of them (60%) show a response with 2 clear partial remissions (40%). Conclusions: Taken together, a dendritic-cell based therapy can be successful in the treatment of GBM. Enhancement of the therapeutically outcome can be induced by a combination therapy with New Castle Disease Virus leading to the suggestion that there may be an interaction between the dendritic cells and the NDV.

No significant financial relationships to disclose.
Phase II clinical trial of mutant Ras peptide vaccine in combination with GM-CSF and IL-2 in advanced cancer patients
Authors: Achtar M. S. , Toubaji A. , Herrin V. , Gause B. , Hamilton M. , Berhens R. , Grollman F. , Bernstein S. , Khleif S.
Published: March 2020

3067

Background: Mutant ras oncogenes produce novel proteins that are processed and displayed through HLA molecules on tumor cells. Therefore, mutant ras is an attractive target for vaccine therapy. We have shown in a previous phase I trial that vaccination with mutant ras peptides produced specific immune responses (IR). Here we tested in a phase II trial the use of specific mutant ras peptides in combination with GM-CSF and IL-2 in advanced cancer patients carrying the ras mutation in their tumors. Methods: We treated 17 patients with advanced cancers (14 CRC, 1 NSCLC and 2 pancreatic) with 5000μg of the corresponding mutant ras peptide given SQ along with GM-CSF and IL-2. GM-CSF was given SQ on days -1,0,1,2 followed by ten days of low dose SQ IL-2. Vaccines were repeated every 5 weeks for a maximum of 15 cycles or until disease progression. Results: 11 patients who received 3 or more vaccinations were tested for immune response by measuring IFN-γ mRNA copies in PBMCs pre and post vaccination. 6/11 patients generated specific IR to the corresponding mutant ras vaccine. The median overall survival and the median progression-free survival for all patients were 25.8 and 13.1 months respectively. However, in the 6 patients with positive IR, it was 39.9 and 17.9 months compared to 18.5 and 15.6 months in the 5 patients who showed no IR. No grade IV toxicity occurred. Most adverse events were Grade I-II toxicities and resolved spontaneously. Grade III toxicities led to IL-2 dose reduction in 3/17 patients (18%). Conclusions: The study showed that vaccination of advanced cancer patients with mutant ras peptides in combination with GM-CSF and IL-2 is safe and can induce specific immune responses. Furthermore, those patients who generated IR showed better clinical outcome, as reflected by PFS and OS. So we believe that this vaccine may form a potentially promising approach in combination with other therapeutic modalities in advanced solid tumors.

No significant financial relationships to disclose.
Donor lymphocyte infusions from Ad-sig-TAA/ecdCD40L vector prime-TAA/ecdCD40L protein boost (VPP) vaccinated allodonors decrease tumor cell growth post allograft
Authors: Deisseroth A. B. , Tang Y. , Akbulut H. , Maynard J. , Petersen L.
Published: March 2020

3071

Background: Individuals of advanced chronological age exhibit an impaired immune response to vaccines. This may be due to a reduction in the ratio of antigen naïve/memory CD4 and CD8 T cells and acquisition of functional defects in activated “helper” CD4 T cells (eg diminished CD40 ligand (CD40L) expression) during the aging process. Methods: In order to circumvent this defective response to vaccines in individuals in the fifth and sixth decades of life, our laboratory has developed an adenoviral vector (Ad-sig- TAA/ecdCD40L) vaccine which is designed for the in vivo target associated antigen (TAA) loading and activation of dendritic cells (DCs), and to overcome the absence of CD40L expression in activated CD4 helper T cells in older individuals. Results: The subcutaneous (sc) injection of this vector leads to the release of a fusion protein composed of a TAA linked to the extracellular domain (ecd) of the CD40 ligand (CD40L), which binds to the CD40 receptor on DCs, activates the DCs, and leads to the presentation of TAA fragments on Class I MHC. Two sc injections of the TAA/ecdCD40L protein as a booster following the sc administration of the Ad-sig-TAA/ecdCD40L vector (VPP) expands the magnitude of the cellular and humoral immune response induced by the vector in 18 month old aged mice as well as in younger mice. This vaccine decreased levels of negative regulatory CD4 FOXP3 T cells in tumor nodules. We administered TBI and an allogeneic stem cell transplant 7 days post sc injection of the E7 positive TC-1 cells. DLI from an Ad-sig-E7/ecdCD40L vector prime-E7/ecdCD40L protein boost vaccinated donor were injected iv 3 days post transplant, and a single E7/ecdCD40L protein boost sc vaccination one week thereafter. We found that the growth rate of the E7 positive TC-1 tumor cells post allograft was less in the vaccinated than in the control (injection of tumor cells followed in 7 days by TBI), or the animals in which the allograft recipient was vaccinated without DLI. Conclusions: Thus, the use of DLI from VPP vaccinated allodonors decreased tumor cell growth post allograft.

No significant financial relationships to disclose.
Xenograft-like destruction of tumors and their conversion into vaccines by intratumoral injection of α-gal glycolipids
Authors: Galili U. , Wigglesworth K. , Abdel-Motal U.
Published: March 2020

3074

Background: We describe a novel immunotherapy exploiting the natural anti-Gal antibody to destroy tumors and convert them into endogenous vaccines. Anti-Gal constitutes 1% of immunoglobulins in humans and interacts specifically with a-gal epitopes (Gala1- 3Galβ1–4GlcNAc-R) on glycolipids and glycoproteins. a-Gal epitopes are abundant in nonprimate mammals. Binding of anti-Gal to a-gal epitopes on pig cells mediates xenograft rejection. We inject glycolipids carrying a-gal epitopes (a-gal glycolipids) into solid tumors. Methods: a-Gal glycolipids extracted from rabbit RBC have carbohydrate chains capped with a-gal epitopes. Efficacy of treatment was studied in a1,3galactosyltransferase knockout mice bearing B16 melanoma. These mice are unique since they lack a-gal epitopes and can produce anti- Gal, like humans. Also B16 cells lack a-gal epitopes. B16 lesions (∼5 mm) were injected with 1mg a-gal glycolipids. Results: Intratumoral injection of a-gal glycolipids results in local inflammation mediated by anti-Gal binding to the ∼2x1016 a-gal epitopes on these glycolipids, activation of complement and generation of chemotactic factors. a-Gal glycolipids insert spontaneously into tumor cell membranes. Binding of anti-Gal to a-gal epitopes on such tumor cells induces lesion destruction, similar to xenograft rejection. Anti-Gal further opsonizes tumor cells for effective uptake by inflammation recruited dendritic cells (DC), via Fcγ receptors of these APC. The DC transport internalized tumor Ags to draining lymph nodes and present tumor Ag peptides, thus activating tumor specific T cells and eliciting an immune response against micrometastases. Conclusions: Injected a-gal glycolipids effectively destroy lesions and convert them into vaccines. This treatment may be even more effective in humans, since complement activity is much higher than in mice. This treatment may also be considered as neo-adjuvant immunotherapy for converting primary tumor into autologous tumor vaccine that elicits a protective immune response against micrometastases, during the period preceding resection of the tumor.

No significant financial relationships to disclose.