bluuebunny/crossref_metadata_2025 huggingface dataset:
Durability of complete remission by moxetumomab pasudotox (HA22 or CAT-8015) assessed by clone-specific real-time quantitative PCR (RQ-PCR).
Authors: Kreitman Robert J. , Arons Evgeny , Sapolsky Jeffrey , Roth Laura , Zhou Hong , Stetler-Stevenson Maryalice , Wilson Wyndham Hopkins , Raffeld Mark , FitzGerald David JP , Ji Fei , Ibrahim Ramy A. , Pastan Ira
Published: March 2020

2503^

Background: The anti-CD22 recombinant immunotoxin moxetumomab pasudotox, also known as HA22 or CAT-8015, was recently reported in phase I testing to achieve complete remissions (CRs) in 13 (46%) of 28 patients with relapsed/refractory hairy cell leukemia (HCL); 3 of 13 patients have relapsed. Methods: To complete this trial, 20 additional patients received the highest dose level (50 µg/Kg every other day x 3 doses); none of the 48 HCL patients had dose-limiting toxicity (DLT). Results: Of the first 42 patients with >6 mo of follow up off-treatment, 23 (55%) had CRs, with an overall response rate of 88%. Of the 23 CRs, 21 were evaluable for minimal residual disease (MRD) using flow cytometry of blood and immunohistochemistry of the bone marrow biopsy, and 17 (81%) were negative. Of these 17 patients, 11 (65%) were negative by bone marrow aspirate (BMA) flow cytometry. PCR using consensus primers for the heavy chain immunoglobulin (IgH) rearrangement was less specific than flow cytometry of blood, since IgH rearrangements of normal B cells, which recovered rapidly after immunotoxin treatment, were also amplified. For better MRD detection in blood, patient IgH sequences were cloned and sequence specific primers and probes designed for real-time quantitative PCR (RQ-PCR). RQ-PCR of blood was negative in 6 (100%) of 6 patients achieving flow-negativity in both blood and BMA and positive in 3 (100%) of 3 patients flow-negative in blood but not BMA (p=0.01). No relapses from CR have been observed in 10 patients who became RQ-PCR-negative in blood or flow-negative in BMA, with 5-38 (median 11) mo of follow-up. Conclusions: We conclude that clone-specific RQ-PCR is the most sensitive blood test for MRD in our HCL patients after moxetumomab pasudotox, and could be used to assess the possibility of long-term molecular remissions. We believe these results, including durable CRs without DLT, support a pivotal trial in which moxetumomab pasudotox is compared with alternative therapy. Note: this summary contains investigator reported data. This study was funded by MedImmune, LLC, and supported by NCI’s Intramural Research Program and the Hairy Cell Leukemia Research Foundation.
A phase I study of EpCAM/CD3-bispecific antibody (MT110) in patients with advanced solid tumors.
Authors: Fiedler Walter M. , Wolf Martin , Kebenko Maxim , Goebeler Marie-Elisabeth , Ritter Barbara , Quaas Alexander , Vieser Eva , Hijazi Youssef , Patzak Ingrid , Friedrich Matthias , Kufer Peter , Frankel Stanley , Seggewiss-Bernhardt Ruth , Kaubitzsch Sabine
Published: March 2020

2504

Background: MT110 is a bispecific T cell engaging antibody construct (BiTE) that directs CD3 expressing T cells to kill target cells that express EpCAM, which is widely found on solid tumors. Methods: Safety, tolerability, pharmacokinetics and anti-tumor activity of MT110 in patients (pts) with advanced solid tumors were studied using a 3+3 design. Continuous IV infusions for at least 28 days of doses ranging from 1 to 48 µg/d have been tested. Stepwise intra-patient dose escalations within cycle 1 or at start of cycle 2 have been explored. Results: 51 pts (6 gastric cancers, 32 CRC, 2 SCLC, 5 NSCLC, 3 HRPC, 1 ovarian cancer) have been treated in 12 dose cohorts. The maximally administered dose includes day 1 dose of 3 µg/d escalated up to 48 µg/d. The maximum tolerable dose (MTD) has not yet been established. Diarrhea and elevations in liver function tests have been reported as dose limiting toxicity (DLT) for individual patients. Transaminase elevations were fully reversible and mitigated by dexamethasone at initiation or escalation of dose. Other adverse events of grade 3 or higher included transient lymphopenia, increase in lipase or amylase, nausea, vomiting, and hypoalbuminaemia. No CNS safety signal was observed. The mean serum half-life of MT110 was 4.5 hours. Mean steady state serum concentrations of MT110 were linear with dose across treatment cycles. At 48 µg/d, the mean Css was 3.2 ng/mL. This compares to preclinical EC90 of 1.35 – 3.85 ng/ml in CRC cell lines. Sixteen pts who received a dose of ≥ 24 µg/d were evaluable for anti-tumor response. Best response of SD was reported in 38%; median duration was 155 days (95% CI 92; 161). Anti-tumor activity was demonstrated on biopsy of liver metastases in one patient. Following at least 1 week of MT110 treatment at 48 µg/d, a decrease in circulating tumor cells was observed with a median nadir 74% below baseline. Conclusions: The use of stepwise dose escalation and concomitant dexamethasone resulted in improved tolerability. A dose of 48 µg/d appears tolerable. Tumor biopsy evaluation on treatment and pharmacodynamic evidence of anti-tumor activity are encouraging. Additional dose cohorts will seek to identify the recommended phase II dose and further evidence of anti-tumor activity.
Effect of stimulation of natural killer cells with an anti-CD137 mAb on the efficacy of trastuzumab, cetuximab, and rituximab.
Authors: Kohrt Holbrook Edwin , Houot Roch , Weiskopf Kipp , Goldstein Matthew , Lund Peder , Scheeren Ferenc , Czerwinski Debra , Colevas A. Dimitrios , Weng Wen-Kai , Clarke Michael F. , Carlson Robert W. , Sunwoo John , Tedder Thomas , Chen Lieping , Levy Ronald
Published: March 2020

2514

Background: Antibody-dependent cell-mediated cytotoxicity (ADCC), mediated by natural killer (NK) cells, plays an important role in the efficacy of monoclonal antibodies (mAb)s. CD137 is a costimulatory molecule expressed on immune cells following activation, including NK cells. We hypothesize that as the antitumor efficacy of mAbs is due to ADCC, their activity can be enhanced by stimulation of NK cells with an anti-CD137 agonistic mAb. Methods: Upregulation of CD137 on NK cells was assessed using CD20+lymphoma, HER2+breast, and EGFR+head and neck cell lines and primary patient samples. NK cell degranulation, cytokine release and cytotoxicity were assessed by CD107a mobilization, IFN-γ secretion, and chromium release. Mechanism of synergy was explored by cell depletion in an immune competent mouse model. Xenotransplanted models were used to demonstrate anti-tumor activity and sufficiency of an innate immune response. Results: NK cells in human primary patient samples do not express CD137 at baseline, however CD137 is highly upregulated when encountering mAb-coated tumor cells. MAb-induced NK cell degranulation and cytotoxicity are enhanced by anti-CD137 agonistic mAb. In a murine lymphoma model, anti-CD137 mAb significantly enhances anti-tumor activity of anti-CD20 mAb leading to complete tumor resolution and prolonged survival. NK cell depletion completely abrogates the therapeutic effect. In seven xenotransplant models, sequential administration of rituximab, trastuzumab or cetuximab plus anti-CD137 mAb provided superior reduction in tumor burden and prolonged overall survival. In a phase 0 biomarker study, level of CD137 expression on circulating and intratumoral NK cells was influenced by disease burden, prior treatment, FcγRIII polymorphism, and time since mAb therapy. Conclusions: Our results demonstrate the synergy of anti-CD137 mAb and a tumor-targeting mAb by stimulation of mAb-activated NK cells with anti-CD137 mAb to enhance ADCC. These results support a novel, sequential antibody approach against CD20+B cell, HER2+breast, and EGFR+head and neck malignancies by targeting first the tumor and then the host immune system.
Investigating genes and pathways that play a role in immune responses mediated by anti-CTLA-4 therapy.
Authors: Gao Jianjun , Chen Hong , Ng Tang Derek , Sharma Padmanee
Published: March 2020

2520^

Background: Blockade of the inhibitory T cell molecule CTLA-4 with a monoclonal antibody has led to enhanced anti-tumor immune responses and clinical benefit. Ipilimumab, an anti-CTLA-4 antibody (BMS), was recently FDA-approved for the treatment of metastatic melanoma. Only a subset of patients benefit from anti-CTLA-4. In order to identify genes and pathways that are induced by anti-CTLA-4, which may be used in future studies for potential correlation with clinical outcomes or provide additional targets for therapy, we purified and analyzed CD4 T cells from patients treated with anti-CTLA-4 for changes in gene expression profile. We also obtained tumor tissues from treated patients for similar studies. Methods: On an IRB-approved Phase Ia pre-surgical clinical trial, 6 patients with localized bladder cancer were treated with two doses of Ipilimumab at 10 mg/kg at weeks 1 and 4. Blood was collected pre-therapy and post-therapy (3 weeks after each dose). CD4 T cells were enriched from peripheral blood by using the CD4 T cell isolation kit from Miltenyi Biotec (Auburn, CA). Total RNA was isolated from purified CD4 T cells using Qiagen RNeasy kit for Affymetrix microarray analyses. Microarray data were then analyzed using Ingenuity iReport (Redwood City, CA). RT-PCR, RPPA and Western blot were used to confirm significant changes in genes or pathways identified in microarray analyses. Results: Ipilimumab treatment resulted in modulation of differentially expressed genes (DEGs). After dose #1, Ipilimumab only modulated 16 DEGs >2-fold (p<0.05) in CD4 T cells. After two doses of treatment, Ipilimumab significantly changed expression of a total of 100 DEGs. Further pathway analyses indicated that Ipilimumab induced a variety of pathways involved in cell cycle control, cell proliferation, apoptosis, and immune modulation. Specifically, these pathways include PI3K/AKT, MAP/ERK, IFN/JAK-STAT, granzyme, and protein ubiquination. Conclusions: Ipilimumab treatment results in modulation of multiple genes and pathways, which likely play important roles in anti-tumor immune responses and need to be considered for future optimization of anti-CTLA-4 therapy and design of combination immunotherapy strategies.
Immune responses and association with clinical outcome of advanced colorectal cancer patients treated with the multi-peptide vaccine IMA910.
Authors: Kuttruff Sabrina , Weinschenk Toni , Schoor Oliver , Lindner Juha , Kutscher Sarah , Maurer Dominik , Mayer-Mokler Andrea , Ludwig Joerg , Nowara Elzbieta , Torday Laszlo , Cseh Jozsef , Hoehler Thomas , Hitre Erika , Maughan Tim , Adams Richard A. , Mayer Frank , Reinhardt Carsten , Singh Harpreet , Walter Steffen
Published: March 2020

2522

Background: IMA910 is a novel multi-peptide cancer vaccine consisting of 10 HLA class I and 3class II tumor-associated peptides (TUMAPs), which were selected based on natural presentation on colorectal tumors by the XPRESIDENT antigen discovery platform. Methods: 92 HLA-A*02+ advanced colorectal cancer (aCRC) patients (pts) with stable or responding disease after 12 weeks of first-line oxaliplatin-based therapy were enrolled in this phase I/II trial. After pre-treatment with cyclophosphamide (300 mg/m2), patients were immunized intradermally with IMA910 plus the immune modulator GM-CSF without (cohort 1; n=66) or with (cohort 2; n=26) topically applied imiquimod, another immune modulator acting via toll-like receptor 7 on antigen presenting cells. T-cell responses to individual IMA910 peptides were analyzed by HLA multimer and intracellular cytokine staining (ICS) assays. Results: IMA910 elicited immune responses towards multiple class I (43%) and class II TUMAPs (65%). 34% of pts responded to multiple class I and class II TUMAPs. Pts that received imiquimod were more often multi-peptide class I responders in the ICS assay (p=0.016) and showed an approx. 2x higher frequency of T-cell response (p=0.12). Responses to multiple class I and class II TUMAPs were associated with higher disease control rate at all time points (all p<0.02), increased time to progression (p=0.006), progression-free survival (p=0.009) and OS (p=0.088, HR=0.53). Baseline characteristics of multi vs. non-multi responders were overall well comparable. In a prospectively defined, blinded matched-pair analysis with patients in arm C of the COIN trial, multi-peptide responder patients showed a prolonged survival vs. corresponding COIN patients (p=0.04), while the non-multi responder patients had comparable survival. Conclusions: IMA910 is immunogenic. Imiquimod increases the quality of immune responses. Responses to multiple TUMAPs are associated with better clinical outcome. Several observations indicate that this association is not a reflection of better prognosis of the immunologically responding subset of patients. These results suggest further development of IMA910.
Exposure-response (E-R) analysis of rilotumumab (R, AMG 102) plus epirubicin/cisplatin/capecitabine (ECX) in patients (pts) with locally advanced or metastatic gastric or esophagogastric junction (G/EGJ) cancer.
Authors: Zhu Min , Tang Rui , Doshi Sameer , Oliner Kelly S. , Kathman Steven , Gisleskog Per Olsson , Dubey Sarita , Jiang Yizhou , Donehower Ross C. , Iveson Timothy , Loh Elwyn
Published: March 2020

2535

Background: R is an investigational, fully human monoclonal antibody to hepatocyte growth factor/scatter factor (HGF/SF), the only known MET receptor ligand. In a double-blind, placebo-controlled, phase 2 trial of 121 pts with G/EGJ cancer, R (7.5 or 15 mg/kg) + ECX showed trends for improved overall survival (OS) and progression-free survival (PFS) compared to ECX alone (placebo, P). Methods: E-R analyses were performed using pharmacokinetic (PK), biomarker, efficacy, and safety data. A population PK model was used to evaluate covariate effects (eg, demographics, ECX, and MET status) on R PK and predict individual R exposure (trough steady-state Cmin [C]). The effect of C on OS/PFS was evaluated with Kaplan-Meier estimates and Cox proportional hazards models. Covariate effects for OS/PFS were evaluated with multivariate analysis. The relationships between adverse events of interest (AEs), lab values, and C were analyzed with descriptive statistics and linear regression models. Results: R showed linear PKs that were unaffected by ECX or MET levels. Pts who received R + ECX were divided into low C (CL) and high C (CH) groups by the median C (94 µg/mL). Median PFS was 4.2, 4.5, and 6.9 months in the P, CL, and CH groups; median OS was 8.9, 9.5, and 13.3 months. Improved OS/PFS in CH and improved PFS in CH and CL groups (vs P) were seen after adjusting for baseline covariates. Pts with tumors that expressed high MET levels (METHigh: > 50% cells positive) showed greater improvement in OS in the CH vs CL group. No improvement in OS was seen in METLow pts (CH and CL groups) compared to placebo (see Table). No relationship was seen between R exposure and AEs or lab values. Conclusions: Higher R exposure was associated with improved OS/PFS in METHigh pts without increased toxicity, supporting further study of R + ECX in G/EGJ cancer. [Table: see text]
Phase I study of weekly oral docetaxel (ModraDoc001) plus ritonavir in patients with advanced solid tumors.
Authors: Marchetti Serena , Stuurman Frederik , Koolen Stijn , Moes Johannes , Hendrikx Jeroen , Thijssen Bas , Huitema Alwin D.R. , Nuijen Bastiaan , Rosing Hilde , Keessen Marianne , Voest Emile E. , Mergui-Roelvink M. , Beijnen Jos H. , Schellens Jan H. M.
Published: March 2020

2550

Background: ModraDoc001 is a novel oral formulation containing docetaxel as a solid dispersion. Oral administration of docetaxel is feasible in combination with the CYP3A4 inhibitor ritonavir. Objectives were to determine the safety, maximum tolerated dose (MTD) and pharmacokinetics (PK) of weekly oral docetaxel (as ModraDoc001) in combination with ritonavir. Methods: Patients with advanced solid tumors, WHO PS ≤ 2, no concomitant use of MDR or CYP3A modulating drugs, adequate bone marrow (ANC ≥ 1.5x109 /L), liver (bilirubin ≤ 1.5xULN, ALAT/ASAT ≤ 2.5xULN) and renal function (creatinine ≤ 1.5xULN or clearance ≥ 50 ml/min) were eligible. Docetaxel (ModraDoc001 10mg capsule) and ritonavir (Norvir 100mg) were simultaneously given once weekly in a ‘3+3 cohort’ dose escalation design. MTD was defined as the highest dose resulting in <1/6 probability of causing a dose limiting toxicity in the first 4 weeks of treatment. This cohort was expanded with 6 patients. PK was determined on days 1 and 8. Results: 40 patients (25 male, 35 evaluable for safety) were enrolled in 6 dose levels (30/100, 40/100, 60/100, 80/100, 60/200 and 80/200 mg docetaxel/ritonavir). Common treatment related adverse events in the 4 highest dose levels were diarrhea (68%), nausea (62%) and fatigue (62%), mostly CTC grade 1-2 (80%, 95% and 73% respectively). Five patients experienced a DLT (grade 3 diarrhea (4), elevated ASAT/ALAT (1), grade 4 dehydration and grade 3 mucositis (1), grade 3 fatigue (2)). The MTD was 60 mg/200 mg docetaxel/ritonavir. Partial remission was seen in 4 patients (CUP, NSCLC, gastric and mamma ca) and sustained stable disease in 15 patients (6x NSCLC). Both drugs were rapidly absorbed after oral administration. Mean Tmax was 2.0 hours (CV=73%) for docetaxel. Cmax and AUC of docetaxel increased less than proportionally with dose to 162 ng/ml (CV= 67%) and 1615 ng/ml*hr (CV= 81%), respectively, in 15 patients at the MTD. Conclusions: At the MTD (once weekly 60 mg docetaxel and 200 mg ritonavir) ModraDoc001 is safe, well tolerated and shows encouraging antitumor activity. The exposure of docetaxel with this regimen is comparable to weekly intravenous administration of 35 mg/m2 docetaxel. Phase II studies in solid tumors are planned.
Thymidylate synthase genotype specific dosing of capecitabine: Proof of concept phase I study.
Authors: Soo Ross A. , Lee Soo-Chin , Tan Wen-Lee , Wang Ling-Zhi , Lim Xn-Yii , Loh Marie , Tan Sing-Huang , Zee Ying Kiat , Wong Andrea LA , Chuah Benjamin , Chan Daniel Boon Yeow , Lim Siew Eng , Goh Boon C. , Soong Richie Chuan Teck , Yong Wei-Peng
Published: March 2020

2551

Background: Thymidylate synthase (TYMS) is the target of fluoropyrimidines (FP). TYMS 3R3R is the predominant genotype in East Asian (EA) patients and is associated with increased TYMS expression, reduced FP related toxicity and relative FP resistance. Dose finding studies for FP were developed in Caucasians, a population that typically harbors TYMS 2R2R and 2R3R genotypes. We hypothesize the recommended phase II dose (RP2D) of capecitabine is higher in 3R3R and similar for 2R allele carriers compared to the FDA approved dose. Objectives 1) To determine the maximal tolerated dose (MTD) and RP2D of capecitabine in EA patients with advanced stage malignancy 2) To determine the safety and toxicity of this regimen and 3) To perform plasma pharmacokinetics (PK) of capecitabine and its metabolites. Methods: EA patients with advanced stage cancer were prospectively allocated into two cohorts: Group A (3R3R) and Group B (2R3R, 2R2R). In each cohort, dose escalation followed a standard phase I 3+3 design. Additional patients were treated at the R2P2 dose level (DL). Initial dose was 1250/m2 bd for 14 days q3w (DL 1) with 125 mg/m2 bd increments subsequently. Pharmacokinetics (PK) of capecitabine and its metabolites were performed using a LC-MS/MS method. Results: 23 patients (Group A=18; group B=5) received 94 cycles (median 2.5, range 1-8). Median age was 58 (range 34-74) years. Median turnaround time for TYMS genotyping was 1 day. In group A, grade 3-4 DLTs were seen in 3 patients: diarhoea, neutropenic fever, hand-foot syndrome, and mucositis. MTD was at DL 4 (1625mg/m2 bd) and the RP2D was 1500mg/m2 bd (DL 3). DL 3 was expanded to n=9. At DL 3, day 1 mean (± SD) capecitabine and 5FU Cmax was 12.3 ± 9.9 and 0.91 ± 0.73 µg/mL, respectively and AUC0 – t was 9.84 ± 5.53 and 1.21 ± 0.54 h*µg/mL, respectively. Compared with DL1, Cmax for capecitabine and 5FU was 2 and 2.02 fold higher and AUC 0-t was 1.49 and 1.59 fold higher at DL3. Accrual in group B was ceased at DL2 due to lack of patient enrolment; no DLT was seen. By ROC analysis, day 1 5FU AUC0 – t of 1.74 h*µg/mL predicted for DLT (p=0.022, sensitivity 100%, specificity 90%). Conclusions: In EA patients with TSER 3R3R, the RP2D was 1500 mg/m2 bd. The D1 5FU AUC0 – t at RP2D was 59% more than the FDA approved dose (DL1).
Phase I and pharmacokinetic (PK)/pharmacodynamic (PD) study of LY2334737, an oral gemcitabine prodrug, in patients (pts) with advanced solid tumors.
Authors: Faivre Sandrine J. , Olszanski Anthony J. , Weigang-Koehler Karin , Riess Hanno , Peng Guangbin , Callies Sophie , Benhadji Karim Adnane , Raymond Eric
Published: March 2020

2554

Background: LY2334737 is a valproic acid-bound carboxylesterase-substrate prodrug of gemcitabine that can be given orally. The primary objective was to define the recommended phase II doses and schedules (sch) of administration of LY2334737 in 28-day cycles. Methods: Eligible pts (ECOG<2) had adequate hematologic, renal, and hepatic functions. In sch-A, LY2334737 was given every other day for 21 days. In sch-B, LY2334737 was given daily every other week. Dose escalation (3+3) was based on CTCAE V3 toxicities. Secondary objectives were PKs (LY2334737, dFdC, dFdU), PD biomarkers (dFdC DNA incorporation, Cytokeratin 18 - M30), and antitumor activity. Results: 57 pts (38 males, 19 females, median age 60 yrs) were treated using 7 dose-levels (40–100 mg/day). Pts received a median of 2 cycles. Dose limiting toxicities (DLTs) at cycle 1 (any dose level) consisted of diarrhea (2pt), AST elevation (1pt), lower extremity edema (1pt), QTC prolongation (1pt), and general deterioration (1pt). A total of 2/7pts treated with 100mg in sch-A and 1/4pts treated with 90mg in sch-B had DLTs. During dose escalation most frequent toxicities were 1) Sch-A (28 pts): nausea (10pts), pyrexia (9pts), vomiting (8pts), mucositis (6pts), anorexia (6pts), ALT elevation (5pts), asthenia (5pts), anemia (5pts), fatigue (4pts), chills (4pts), and lymphopenia (4pts). 2) Sch-B (29 pts): pyrexia (13pts), nausea (8pts), diarrhea (6pts), vomiting (5pts), chills (6pts), anemia (5pts), asthenia (6pts), AST elevation (6pts), ALT elevation (5pts), and fatigue (4pts). Nine pts had stable disease (3pts completed >6 cycles). PKs showed a dose-proportional increase in exposure of LY2334737 and dFdC with no accumulation after repeated dosing. dFdC is detected in the DNA of peripheral blood mononuclear cells (increasing amount with dose and over time after repeated cycle). In sch-A, we observed a significant increase in cytokeratin 18 M30 relative to baseline. Conclusions: LY2334737 displayed linear PK and acceptable safety profile in both schedules. The dose of 90mg given every other day is the recommended dose for phase II trials with LY2334737 (dose expansion is ongoing).
Human papillomavirus type 16 (HPV16) E6/E7-specific cytotoxic T lymphocytes (CTL) for immunotherapy of HPV-associated cancer (Ca).
Authors: Ramos Carlos Almeida , Narala Neeharika , Leen Ann M. , Gerdemann Ulrike , Sturgis Erich M. , Anderson Matthew L. , Savoldo Barbara , Heslop Helen E. , Brenner Malcolm K. , Rooney Cliona M.
Published: March 2020

2558

Background: Vaccines prevent HPV-associated Ca, but their benefits in established Ca are disappointing: although these tumors express viral E6 and E7 antigens (Ags) immune responses are limited even after vaccination, likely due to negative environmental cues that block tumor recognition and T cell (TC) activation in vivo. We postulated that ex vivo stimulation of TCs in an immunologically favorable milieu would allow us to reactivate tumor-directed CTLs from Ca patients and benefit the recipients on reinfusion. Methods: We studied 68 patients with HPV+ Ca. To detect HPV16 E6/E7-specific TCs (HPV-TCs) in blood, we measured the IFNγ ELISpot responses of TCs stimulated by monocyte-derived dendritic cells (DCs) loaded with pepmixes (peptide libraries of 15-mers overlapping by 11 aa) spanning E6/E7. Because HPV-TCs from these patients may be anergized by their tumors, potent Ag presenting strategies might be required for reactivation, and thus we stimulated these cells in the presence of IL-6, -7, -12 and -15, as we have shown that these can induce responses to poorly immunogenic Ags. Results: We successfully reactivated HPV-TCs from 8/16 cervical and 33/52 oropharyngeal Ca patients. We could expand these HPV-TCs to clinically useful numbers by using patient B-cell blasts (BBs) as APCs. Stimulation of DC-stimulated HPV-TCs by E6/E7 pepmix-loaded BBs further expanded (3.8 ± 1.5×/round) HPV-TC lines, which phenotypically are almost exclusively composed of TCs (98 ± 3% CD3+), with a variable proportion of mostly effector memory (CD45RA–, CD45RO+, CD62L– and CCR7–) CD4+ and CD8+ cells (37 ± 28% and 49 ± 27%, respectively). The viral/tumor associated epitopes recognized mapped to E6 aa 49-71, 77-91 and 125-143, and E7 aa 1-19 and 73-87. The expanded cells from patients killed E6/E7+ targets (specific lysis up to 45-61% vs. 0-8% in controls, 40:1 E:T ratio). Conclusions: We have developed a system that allows the robust generation of HPV-directed CTLs from patients with HPV16+ Ca, which recognize specific epitopes in tumor-associated Ags. Our lines have the potential to be used for adoptive cellular immunotherapy of HPV+ Ca.
IFN-γ to improve immunotherapy for melanoma.
Authors: Donia Marco , Hansen Morten , Sendrup Sarah Louise , Ellebaek Eva , Iversen Trine Zeeberg , Andersen Mads Hald , thor Straten Per , Svane Inge Marie
Published: March 2020

2565

Background: Adoptive cell therapy (ACT) with tumor infiltrating lymphocytes (TILs) holds the promise to change the long-term prognosis of patients with metastatic melanoma. In this study we have explored strategies to improve the efficacy of cell products for infusion through tumor immune-sensitization. Methods: We examined whether objective responses in our pilot ACT trial (NCT937625) were associated with the number of tumor-reactive T cells infused. Subsequently, we assessed the ability of immune-sensitizing agents to modulate the constitutive response of 12 clinical grade TIL products to matched autologous short-term cultured melanoma cell lines. Results: Our data showed that a high absolute number of infused tumor-reactive T cells is critical to achieve an objective response. In addition, a defective population of tumor-specific CD8+ and CD4+ T cells unable to exert antitumor effector functions ex vivo was detected in most TIL products. However, an antitumor specific response could be restored by pretreatment of the autologous tumor cells with low dose IFN-γ. Of note, IFN-γ treatment was invariably associated with increased cancer immunogenicity as demonstrated by up-regulation of MHC molecules. Conclusions: Combination strategies represent the next frontier of cancer immunotherapy. Although previous trials in melanoma showed that IFN-γ does not mediate clinical benefit when used as monotherapy, our findings show that its ability to increase tumor cell immunogenicity may enhance the efficacy of current immune-based therapies such as ACT through improved activation of pre-existing but unresponsive tumor specific lymphocytes. Therefore, additional studies on the possibility of a sequential combination of low dose IFN-γ and ACT are highly warranted.
Human pharmacokinetic (PK) characterization of the novel dual-action anti-HER3/EGFR antibody MEHD7945A (MEHD) in patients with refractory/recurrent epithelial tumors.
Authors: Hidalgo Manuel , Calles Antonio , Juric Dejan , Dienstmann Rodrigo , Roda Perez Desamparados , Messersmith Wells A. , Blumenschein George R. , Baselga José , Tabernero Josep , Cervantes-Ruiperez Andres , Jimeno Antonio , Jin Denise , Bai Shuang , Gurevich Pavel , Nijem Ihsan , Holden Scott N. , Davis John D , Halpern Wendy , Pirzkall Andrea , Xin Yan
Published: March 2020

2567

Background: MEHD is a novel dual-action human IgG1 antibody that blocks ligand binding to HER3 and EGFR, and elicits antibody-dependent cell-mediated cytotoxicity (ADCC). MEHD demonstrates single-agent activity in a broad panel of tumor models, including models resistant to anti-HER3 or anti-EGFR treatment alone. The objective of this analysis was to characterize the PK of MEHD associated with body weight (BW)-based dosing used in a phase I study in patients with epithelial tumors and to evaluate the potential for using fixed dosing in future studies. Methods: Preliminary non-compartmental and population PK analyses were performed using patient data from the dose-escalation stage [1, 4, 10, 15, 22, and 30 mg/kg every two weeks (q2w)] and expansion stage (14 mg/kg q2w) of the phase I study. Patient demographic data and other relevant clinical covariates were evaluated in the population analysis. PK simulation of 1000 subjects with a log-normal BW distribution was performed to compare the inter-individual variability of MEHD exposure following fixed or BW-based dosing. Results: As expected,MEHD exhibited nonlinear PK. In the noncompartmenal analysis, the apparent clearance (CL) decreased in a dose-dependent fashion (about 40 to 9.9 mL/day/kg from 1 to 30 mg/kg) and approached linearity at doses >10 mg/kg (q2w). In the population analysis, the PK profile of MEHD was well described by a two compartment model with linear and nonlinear clearance. The target-mediated clearance was consistent with that of anti-EGFR antibodies. The nonspecific CL and central volume of distribution (V1) values were approximately 6 mL/day/kg and 52.4 mL/kg, respectively. BW had a moderate effect on V1, but not on CL. PK simulations suggest that, compared with BW-based dosing, fixed dosing would result in less inter-individual variability in MEHD exposure. Both 1100 mg q2w or 1650 mg q3w of MEHD achieve the targeted therapeutic exposure. Conclusions: The dual-action antibody MEHD demonstrated PK consistent with anti-EGFR antibodies. Fixed dosing of MEHD on an every 2 or 3 week schedule is supported.
Effect of matrix metalloproteinase-2 on antitumor immunity.
Authors: Godefroy Emmanuelle , Gallois Anne , Manches Olivier , Jotereau Francine , Bhardwaj Nina
Published: March 2020

2570

Background: Cancer cells, including melanoma, can be highly resistant to traditional treatments such as chemotherapy and radiotherapy. As a result, a lot of effort has been put into developing immune therapies to treat cancer patients. The main barrier to design effective immunotherapies is the immunosuppression induced by the tumor. Matrix metalloproteinase-2 (MMP-2) is over-expressed in most cancers including melanoma, and its expression is associated with increased dissemination and poorer survival/prognosis. Here, we uncovered an immunosuppressive role of MMP-2 in inducing ineffective/detrimental TH2 immune responses and its underlying mechanisms. Methods: Human dendritic cells (DCs) were cultured in the presence of MMP-2 or various TLR agonists. DCs responses were monitored using immunostaining, ELISA or cytometric bead array methods. Autologous CD4+ T cells were stimulated using these conditioned tumor-associated antigen (TAA)-pulsed DCs. TAA-specific CD4+ T cells were cloned and characterized using the same techniques as for DCs. Results: Herewe showed that MMP-2-conditioned human DCs primed naïve CD4+ T cells into an inflammatory TH2 phenotype, i.e. mainly secreting TNFα, IL-4 and IL-13 and expressing GATA3. Accordingly, we detected MMP-2-specific CD4+ T cells displaying the same inflammatory TH2 profile in tumor-infiltrating lymphocytes from melanoma patients. We revealed the underlying mechanisms: on the one hand, MMP-2 was found to degrade the type-I IFN receptor IFNAR1, thereby preventing STAT1 phosphorylation, which is necessary for IL-12 production. On the other hand, MMP-2 triggers the Toll-like receptor (TLR)-2 on DCs, which leads to NF-kB activation and OX40L expression. Both lack of IL-12 and over-expression of OX40L were found responsible for skewing T cell responses towards a detrimental TH2 phenotype. Conclusions: MMP-2, therefore, acts as an endogenous TH2 "conditioner" and may underlie the prevalence of detrimental TH2 responses in cancer. Our findings also described the responsible MMP-2-dependent mechanisms, which open the way to novel therapeutic strategies and/or targets to skew anti-tumor CD4+ T cell responses towards a more efficient anti-tumor TH1 phenotype to treat cancer patients.
Correlation of interferon-g (IFN-γ) response with survival in a phase II hyperacute (HAL) immunotherapy trial for non-small cell lung cancer (NSCLC).
Authors: Morris John Charles , Rossi Gabriela R. , Harold Nancy , Tennant Lucinda , Ramsey William Jay , Vahanian Nicholas N. , Link Charles J.
Published: March 2020

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Background: Lung cancer is the leading cause of cancer-related mortality. Patients progressing after initial systemic therapy have a poor prognosis. Thus, new therapies are needed. HAL immunotherapy exploits the hyperacute rejection of a xenotransplant as defense mechanism to initiate anti-tumor immune response by administering genetically modified allogeneic tumor cells expressing the αGal moieties on their cell surface. HAL immunotherapy utilizes αGal epitopes and natural human antibodies (Ab) against these targets as the proposed mechanism for anti-tumor immunity. Methods: We completed a phase II study of HAL immunotherapy in patients with metastatic or recurrent NSCLC, age ≥18, ECOG PS ≤2, ≤2 prior systemic therapies. Trial objectives were to determine response rate, safety and immunological responses. Patients received 300 x 106 HAL cells every 2 weeks for 8 doses. Response was determined using RECIST and adverse events were assessed using CTCAE v3. Immune responses were assessed by changes in serum anti-αGal titers and IFN-γ response. Results: Twenty-eight patients were treated. Eight (29%) demonstrated stable disease (SD) ≥16 wks including one patient that initially progressed and later regressed, surviving over 40 months. Median overall survival (OS) was 11.3 months (95% CI 3.8-21.9). Post vaccination, all patients responded by increasing anti-αGal Ab levels (2-100 fold) and 61% (11/18) of tested patients showed increases in IFN-γ levels (by ELISPOT). Interestingly, patients with increased IFN-γ responses after vaccination (>10-500 fold-increase compared to baseline) had a median survival of 21.9 months compared to 5.5 months in patients with lesser IFN-γ responses after vaccination (p<0.001). In addition, patients with higher IFN-γ responses showed reactivity to a NSCLC cell line that was not a component of HAL, suggesting cross-priming to shared tumor antigens. Conclusions: HAL immunotherapy is safe and feasible. The median survival compared favorably to that reported in patients receiving 2nd line chemotherapy for relapsed or advanced NSCLC. The correlation between IFN-γ response and survival is highly encouraging.
Does the addition of molecular targeted therapy to standard treatments lead to better or worse outcomes overall? A systematic review of EGFR-targeted therapies used in combination with standard treatments.
Authors: Rauw Jennifer , Ennis Marguerite , Krzyzanowska Monika K. , Sridhar Srikala S.
Published: March 2020

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Background: Combining novel targeted therapies with standard treatment is a common strategy in drug development. The primary aim of this systematic review was to provide a summary of the outcomes from studies combining EGFR targeted therapy (ETT) with standard treatments. Methods: A PubMed (1975-Jan, 2012) and ASCO (2005-2011) abstract database search was performed. Eligible studies were RCTs that compared standard therapies (chemotherapy, radiation therapy, or hormonal therapy) to standard therapy plus an ETT. Efficacy outcomes: overall survival (OS), progression free survival (PFS), objective response rate (ORR) time to progression (TTP), clinical benefit rate (CBR), and toxicity (total and grade 3+) were recorded. If any toxicity was significantly more frequent in one arm it was coded as such. Results: 128 studies (60 manuscripts, 68 abstracts) met criteria. Median study enrolment was 230 patients, with breast, lung, and colorectal cancer as the main tumor sites. ETT, cetuximab (41%), trastuzumab (19%), gefitinib (13%), erlotinib (13%), and lapatinib (16%), was combined with platinums, 5FU, taxanes, nucleoside analogs; hormonal therapy and/or radiation therapy. Refer to the table for efficacy results. Most frequent toxicities (common and grade 3+) in the combined arm were rash, diarrhea, hematological toxicity and fatigue. Conclusions: Despite enthusiasm for combining standard treatments with targeted therapies, we have demonstrated mixed efficacy results, with marginal benefit and worse toxicity. Quality of life (Q of L) was rarely reported. A similar analysis is underway for VEGFR, and mTor inhibitors, but raises the question of how best to approach the question of combination therapy. [Table: see text]
Bispecific Fynomer-antibody fusion proteins targeting two epitopes on HER2.
Authors: Mourlane Frederic , Toller Isabella , Brack Simon , Grabulovski Dragan , Bertschinger-Ehrler Julian
Published: March 2020

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Background: Fynomers are small binding proteins (7 kDa) derived from the SH3 domain of Fyn kinase. They can be engineered to yield specific and high-affinity binding domains to target proteins of interest. In the past, we have isolated Fynomers with excellent physico-chemical properties binding to 16 different antigens. One important application of the Fynomer technology represents the genetic fusion of a Fynomer to an antibody to provide bispecific fusion proteins. Methods: Using phage display technology we have isolated Fynomers binding to tumor-associated antigens. After genetic fusion of these Fynomers to antibodies of interest the resulting bispecific proteins were evaluated in vitro and in vivo for their antitumoral activity. Results: The fusion of Fynomers to the antibodies of interest did not alter the favorable biophysical properties of the antibodies. First, the Fynomer-antibody fusion proteins could be purified with the same high yields from the supernatant of transiently transfected CHO cells as the unmodified antibodies (in the range of 100 mg/L). Second, the purified fusion proteins were monomeric and showed no signs of aggregation even after four months of storage at 4 °C or -20 °C in PBS as determined by size exclusion chromatography. Third, the Fc-mediated effector functions of antibodies were not altered by their fusion with Fynomers. Antibody-dependent cellular cytotoxicity (ADCC) was maintained, and the affinity to the neonatal Fc-receptor (FcRn) was similar as observed for the unmodified antibody. In addition, the bispecific Fynomer-antibody fusion proteins demonstrated excellent growth inhibition of tumor cells in vitro and high efficacy in vivo in tumor xenograft mouse models. Conclusions: These encouraging preclinical results indicate that the bispecific Fynomer-antibody fusions have highly promising properties with a great potential for further preclinical and clinical development.
Development of an assay based on SOMAmer affinity reagents that detects drug-unbound serum EGFR in the presence of cetuximab and panitumumab.
Authors: Park Noh Jin , Wang Xiuqiang , Root Dana , Diaz Angelica , Sun Weimin , Morrone Robert j , Waldman Frederic , Strom Charles m
Published: March 2020

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Background: EGFR is an oncogene product whose extracellular domain (ECD) can be either up-regulated or down-regulated in serum of patients with various cancers. In colon cancer patients with positive tissue EGFR expression, 2 EGFR ECD-targeting monoclonal antibody drugs, cetuximab (Erbitux) and panitumumab (Vectibix), are widely used chemotherapeutic agents. Patient responses to these drugs vary, and the mechanism of this variability remains unelucidated. Methods: A Slow Off-Rate Modified Aptamer (SOMAmer) targeting the EGFR ECD was selected via Systematic Evolution of Ligands by Exponential Enrichment (SELEX). Using this SOMAmer as a capturing reagent and based on published studies ( Gold et al. PLoS ONE; Dec 7, 2010:10.1371/journal.pone.0015004), we developed a quantitative serum EGFR assay to reliably quantify EGFR in serum. Results: Recovery tests using various amounts of purified EGFR spiked into serum demonstrated a full level of EGFR. Intra and inter assay variability were tested and showed minimum variability. The detection range is 0.95 ng/ml to 600 ng/ml. Interestingly, when serum samples from patients taking cetuximab or panitumumab at the time of blood collection were tested, we observed markedly lower levels of EGFR-captured SOMAmer. ELISA assays from 2 different vendors showed normal to high levels of EGFR in these samples. We further showed that pretreatment of normal serum with either cetuximab or panitumumab can dose-dependently reduce the EGFR SOMAmer signal. The data suggest that our EGFR SOMAmer assay detects serum EGFR molecules that are unbound by cetuximab or panitumumab. Some treated patient samples had more drastic reductions in circulating serum EGFR than others. Conclusions: Various assay development parameters such as accuracy, detection range, and intra and inter assay variability showed that a SOMAmer-based assay detecting serum EGFR can be used in a clinical setting. Our data suggest that this assay can accurately measure drug-unbound EGFR in patients, which may serve as a surrogate drug efficacy indicator, and this may help physicians to adjust the drug dosage. Further studies will be necessary to investigate this possibility.
Phase I and pharmacokinetic (PK) study of pazopanib (P) in combination with two schedules of ifosfamide (I) in patients (pts) with advanced solid tumors (STs).
Authors: Hamberg Paul , Boers-Sonderen Marye , Loos Walter J. , De Jonge Maja J. , Van Der Graaf Winette T.A. , Suttle Ben B , Eskens Ferry , Verweij Jaap , Van Herpen Carla , Sleijfer Stefan
Published: March 2020

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Background: P is a tyrosine kinase inhibitor of PDGFR, VEGFR and KIT. This study aimed to determine the recommended phase II dose (RP2D) of P combined with I. To assess the impact of scheduling on tolerability, two I schedules were explored. Methods: Pts with progressive ST, no standard therapy available, PS 0-1 and good organ function were eligible. Pts received daily P with 3-weekly I, 9 g/m2/cycle, either continuously (Iciv) or as 3 hrs boluses (Ibolus) for 3 days. P was escalated in serial cohorts of 3-9 pts per I-schedule. If in 3-6 pts dose-limiting toxicity (DLT) of 33.3% within 1st cycle was seen 3 more pts at that dose level (DL) were enrolled. RP2D was exceeded if in > 1/3 pts, > 2/6 pts or ≥ 3/9 pts DLT occurred. P was maximized at 1000 mg/day. At RP2D, an expansion cohort of 6-9 pts was studied to confirm safety. PK samples of P and I were collected in all pts. Sampling allowed intra-individual comparison of I-PK with or without P and vice versa. Results: 47 pts were studied. For Iciv (25 pts), RP2D was the maximum dose of P (1000 mg), higher than the single agent RP2D. At RP2D 2 DLTs in 15 pts occurred: 1 febrile neutropenia (FN); 1 encephalopathy. With Ibolus (22 pts), P 400 mg with or without GCSF was not tolerated (5 DLTs in 10 pts: 3*FN, 1 encephalopathy; 1 proteinuria). At RP2D (P 200 mg + Ibolus + GCSF) 3 DLTs in 12 pts (FN; encephalopathy, renal insufficiency) were observed. Toxicity occurring in >30% of pts in Iciv (all grades/grade 3-4,%) were neutropenia (92/92) anemia (92/8); thrombocytopenia (35/12), elevated ASAT, ALAT, alkaline phosphatase (73/4; 73/0; 62/2), nausea (58/0), vomiting (73/0), diarrhea (54/0) and hypertension (31/12). 4/25 pts in Iciv evaluable for response had PR (2 sarcoma, 2 ovary) and 10 prolonged (≥3 mths) SD. In Ibolus, 6/20 pts had PR (2 urothelial, 1 sarcoma, 1 ovary, 1 CUP, 1 mesothelioma) and 3/20 prolonged SD. Preliminary PK analysis showed no effect of P on I-exposure, neither of Ibolus or Iciv on P. Conclusions: P is tolerated at a higher dose combined with Iciv compared to Ibolus (1000 vs 200 mg). PK cannot explain this difference. This study underlines the impact of scheduling on the tolerability of VEGFR-TKI and cytotoxic drug combinations.
Pharmacokinetic modeling and simulation (PK M&S) supported dose escalation of PF-03446962, a monoclonal antibody (mAb) against activin receptor like kinase 1, in patients with solid tumors.
Authors: Wang Erjian , Borghaei Hossein , Goff Laura Williams , Noberasco Cristina , Cohen Roger B. , Stampino Corrado Gallo , Williams James Andrew , De Braud Filippo , Berlin Jordan
Published: March 2020

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Background: PF-03446962 is a first in class mAb. The PK of mAbs is complex, as their clearance (CL) can be linear or non-linear, besides extremely slow. Caution must be exercised when designing mAbs’ dose escalation schemes. Along with safety and activity evaluation, we used PK M&S in real time to ensure that subsequent recommended doses did not expose too many patients to subtherapeutic levels while preserving safety. Methods: The model incorporated both Michaelis-Menten approximation and linear components. A prespecified target exposure was defined by preclinically projected therapeutic and toxic concentrations. The PK M&S results were used to make dose escalation decisions. Results: Eight dose levels (0.5, 1, 2, 3, 4.5, 6.75, 10, and 15 mg/kg) were studied in 44 patients. CL of PF-03446962 exhibited nonlinear characteristics at low doses and linear at high doses. CL was saturated at dose levels of 3 mg/kg and above. Mean half-life was 2.6 days for the first dose level and 12-15 days after CL saturation. The dose ratio of 15 to 0.5 mg/kg was 30, while its corresponding Cmax and AUC ratios were 46 and 97, respectively. However, the PK M&S accurately predicted exposure following each dose. 95% of the observed drug concentrations across all dose levels were within the predicted values. Concentrations at the 4.5 mg/kg dose exceeded the predicted efficacious level over the dosing period. None of 44 patients in the study were exposed to the toxic level derived from a study in monkeys. PK data also implied a biologically active dose at 2 mg/kg dose and above, confirmed by observing target toxicities (ie, telangiectasia) and clinical tumor responses. One patient with PR was at the 2 mg/kg dose and 2 patients with PR were at the 10 mg/kg. The PK M&S well predicted the drug exposure following multiple doses in patients, indicating that patients did not develop antidrug immunogenicity. Conclusions: The PK M&S based approach ensured that the majority of patients were treated at or near the therapeutic dose. It can be readily implemented in the conduct of dose escalation trials of antitumor mAbs, while minimizing risk to patients and maximizing efficiency.