Pembrolizumab plus chemotherapy in Japanese patients with metastatic squamous non-small-cell lung cancer in KEYNOTE-407.

The global phase III KEYNOTE-407 (NCT02775435) trial showed that pembrolizumab plus chemotherapy prolonged overall and progression-free survival (OS/PFS) versus placebo plus chemotherapy in patients with metastatic squamous non-small-cell lung cancer (NSCLC). We present outcomes of patients from Japan enrolled in KEYNOTE-407. Patients were randomized 1:1 to receive pembrolizumab 200 mg or placebo with paclitaxel 200 mg/m2 every 3 weeks (Q3W) or nab-paclitaxel 100 mg/m2 (weekly) plus carboplatin area under the concentration-time curve of 6 mg/mL/min Q3W for four cycles, followed by pembrolizumab or placebo Q3W for a total of 35 cycles. Primary end-points were OS and PFS per RECIST version 1.1 by blinded independent central review. Fifty patients were randomized at Japanese sites (pembrolizumab plus chemotherapy, n = 22; placebo plus chemotherapy, n = 28). Median follow-up time at data cut-off (May 9, 2019) was 15.1 (range, 0.5-24.0) months. Median OS (95% confidence interval [CI]) was 17.3 (12.5-not reached) versus 11.0 (8.6-19.5) months in the pembrolizumab plus chemotherapy versus placebo plus chemotherapy group (hazard ratio [HR] 0.56; 95% CI, 0.27-1.15). Median PFS (95% CI) was 8.3 (6.1-13.0) versus 7.2 (3.9-8.8) months (HR 0.65; 95% CI, 0.35-1.23). Grade 3-5 adverse events (AEs) occurred in 86% and 75% of patients, respectively. There were three fatal AEs, two of which were treatment-related (one from each treatment group, pneumonitis and pulmonary hemorrhage). Efficacy and safety outcomes were consistent with the global study and support the use of pembrolizumab plus chemotherapy in Japanese patients with metastatic squamous NSCLC.

Pembrolizumab Plus Chemotherapy in Squamous Non-Small-Cell Lung Cancer: 5-Year Update of the Phase III KEYNOTE-407 Study.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.We report 5-year efficacy and safety outcomes from the phase III KEYNOTE-407 study (ClinicalTrials.gov identifier: NCT02775435). Eligible patients with previously untreated, metastatic squamous non-small-cell lung cancer (NSCLC) were randomly assigned 1:1 to pembrolizumab 200 mg or placebo plus carboplatin and paclitaxel/nab-paclitaxel once every 3 weeks for four cycles, followed by pembrolizumab or placebo for up to 35 cycles. Primary end points were overall survival (OS) and progression-free survival (PFS) per RECIST version 1.1 by blinded independent central review (BICR). Five hundred fifty-nine patients were randomly assigned in the intention-to-treat population (pembrolizumab plus chemotherapy, n = 278; placebo plus chemotherapy, n = 281). The median time from random assignment to data cutoff was 56.9 (range, 49.9-66.2) months. OS and PFS were improved with pembrolizumab plus chemotherapy versus placebo plus chemotherapy (hazard ratio [95% CI], 0.71 [0.59 to 0.85] and 0.62 [0.52 to 0.74]), with 5-year OS rates of 18.4% versus 9.7%, respectively. Toxicity was manageable. Among 55 patients who completed 35 cycles of pembrolizumab, the objective response rate was 90.9% and the 3-year OS rate after completion of 35 cycles (approximately 5 years after random assignment) was 69.5%. Pembrolizumab plus chemotherapy maintained an OS and PFS benefit versus placebo plus chemotherapy in previously untreated, metastatic squamous NSCLC and is a standard-of-care first-line treatment option for metastatic squamous NSCLC regardless of programmed death ligand 1 expression.

Pembrolizumab Plus Pemetrexed and Platinum in Nonsquamous Non-Small-Cell Lung Cancer: 5-Year Outcomes From the Phase 3 KEYNOTE-189 Study.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically on the based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.We present 5-year outcomes from the phase 3 KEYNOTE-189 study (ClinicalTrials.gov identifier: NCT02578680). Eligible patients with previously untreated metastatic nonsquamous non-small-cell lung cancer without EGFR/ALK alterations were randomly assigned 2:1 to pembrolizumab 200 mg or placebo once every 3 weeks for up to 35 cycles with pemetrexed and investigator's choice of carboplatin/cisplatin for four cycles, followed by maintenance pemetrexed until disease progression or unacceptable toxicity. Primary end points were overall survival (OS) and progression-free survival (PFS). Among 616 randomly assigned patients (n = 410, pembrolizumab plus pemetrexed-platinum; n = 206, placebo plus pemetrexed-platinum), median time from random assignment to data cutoff (March 8, 2022) was 64.6 (range, 60.1-72.4) months. Hazard ratio (95% CI) for OS was 0.60 (0.50 to 0.72) and PFS was 0.50 (0.42 to 0.60) for pembrolizumab plus platinum-pemetrexed versus placebo plus platinum-pemetrexed. 5-year OS rates were 19.4% versus 11.3%. Toxicity was manageable. Among 57 patients who completed 35 cycles of pembrolizumab, objective response rate was 86.0% and 3-year OS rate after completing 35 cycles (approximately 5 years after random assignment) was 71.9%. Pembrolizumab plus pemetrexed-platinum maintained OS and PFS benefits versus placebo plus pemetrexed-platinum, regardless of programmed cell death ligand-1 expression. These data continue to support pembrolizumab plus pemetrexed-platinum as a standard of care in previously untreated metastatic non-small-cell lung cancer without EGFR/ALK alterations.

First-Line Pembrolizumab Plus Chemotherapy for Advanced Squamous NSCLC: Real-World Outcomes at U.S. Oncology Practices.

Introduction: Pembrolizumab plus carboplatin and (nab-)paclitaxel (pembrolizumab-chemotherapy) is currently an approved and recommended systemic therapy for patients with previously untreated advanced squamous NSCLC. This retrospective study evaluated real-world time on treatment (rwToT) and overall survival (OS) among patients with advanced squamous NSCLC treated with first-line pembrolizumab-chemotherapy at oncology practices in the United States. Methods: Using a real-world database, we selected adult patients with newly diagnosed or recurrent advanced squamous NSCLC (unresectable stages IIIB, IIIC, or IV) and good performance status (Eastern Cooperative Oncology Group 0-1) who initiated first-line pembrolizumab-chemotherapy from November 1, 2018, to May 31, 2020. The Kaplan-Meier method was used to determine rwToT and OS overall and by programmed death-ligand 1 (PD-L1) expression. Data cutoff was October 31, 2021. Results: Of 364 eligible patients, 243 (67%) were men; median age was 70 (range: 43-84) years; and PD-L1 expression was greater than or equal to 1%, less than 1%, and unknown for 172 (47%), 94 (26%), and 98 patients (27%), respectively. Median follow-up from pembrolizumab-chemotherapy initiation to data cutoff was 26.2 months. Overall, median pembrolizumab rwToT was 6.5 months (95% confidence interval [CI]: 5.6-7.6), with on-treatment rates of 29.3% and 15.9% at 12 and 24 months, respectively. Median OS was 15.3 months (95% CI: 11.7-18.6), with 12- and 24-month OS rates of 54.9% and 37.3%, respectively. Median OS did not differ with PD-L1 expression: 16.2 months (95% CI: 10.3-20.6) for PD-L1 greater than or equal to 1% and 17.2 months (95% CI: 10.8-20.6) for PD-L1 less than 1%. Conclusions: For patients with advanced squamous NSCLC and good performance status treated with first-line pembrolizumab-chemotherapy, rwToT and OS are similar to clinical trial findings for treatment duration and OS.

Circulating Immune Cell and Outcome Analysis from the Phase II Study of PD-L1 Blockade with Durvalumab for Newly Diagnosed and Recurrent Glioblastoma.

PURPOSE: PD-L1 is upregulated in glioblastoma and supports immunosuppression. We evaluated PD-L1 blockade with durvalumab among glioblastoma cohorts and investigated potential biomarkers. PATIENTS AND METHODS: MGMT unmethylated newly diagnosed patients received radiotherapy plus durvalumab (cohort A; n = 40). Bevacizumab-naïve, recurrent patients received durvalumab alone (cohort B; n = 31) or in combination with standard bevacizumab (cohort B2; n = 33) or low-dose bevacizumab (cohort B3; n = 33). Bevacizumab-refractory patients received durvalumab plus bevacizumab (cohort C; n = 22). Primary endpoints were: OS-12 (A), PFS-6 (B, B2, B3), and OS-6 (C). Exploratory biomarkers included: a systematic, quantitative, and phenotypic evaluation of circulating immune cells; tumor mutational burden (TMB); and tumor immune activation signature (IAS). RESULTS: No cohort achieved the primary efficacy endpoint. Outcome was comparable among recurrent, bevacizumab-naïve cohorts. No unexpected toxicities were observed. A widespread reduction of effector immune cell subsets was noted among recurrent patients compared with newly diagnosed patients that was partially due to dexamethasone use. A trend of increased CD8+Ki67+ T cells at day 15 was noted among patients who achieved the primary endpoint and were not on dexamethasone. Neither TMB nor IAS predicted outcome. CONCLUSIONS: Patients with recurrent glioblastoma have markedly lower baseline levels of multiple circulating immune cell subsets compared with newly diagnosed patients. An early increase in systemic Ki67+CD8+ cells may warrant further evaluation as a potential biomarker of therapeutic benefit among patients with glioblastoma undergoing checkpoint therapy. Dexamethasone decreased immune cell subsets. PD-L1 blockade and combination with standard or reduced dose bevacizumab was ineffective.

Pembrolizumab Plus Chemotherapy for Chinese Patients With Metastatic Squamous NSCLC in KEYNOTE-407.

INTRODUCTION: Pembrolizumab plus chemotherapy significantly improved survival outcomes versus placebo plus chemotherapy in patients with previously untreated metastatic squamous NSCLC in the randomized, double-blind, phase 3 KEYNOTE-407 study. We present the results of Chinese patients enrolled in the KEYNOTE-407 global and China extension studies. METHODS: Patients enrolled from mainland China in the KEYNOTE-407 global (NCT02775435) and China extension studies (NCT03875092) were randomized 1:1 to 35 cycles of pembrolizumab or placebo plus four cycles of carboplatin and paclitaxel or nab-paclitaxel. Dual primary end points were overall survival (OS) and progression-free survival (PFS) (based on the Response Evaluation Criteria in Solid Tumors version 1.1 by blinded independent central review). RESULTS: A total of 125 patients were randomized (pembrolizumab-chemotherapy, n = 65; placebo-chemotherapy, n = 60). As of September 30, 2020, median (range) study follow-up was 28.1 (25.1‒40.9) months. Pembrolizumab-chemotherapy improved OS (hazard ratio [HR] = 0.44, 95% confidence interval [CI]: 0.28-0.70) and PFS (HR = 0.35, 95% CI: 0.24-0.52) versus placebo-chemotherapy. Two-year OS and PFS rates for pembrolizumab-chemotherapy versus placebo-chemotherapy were 56.9% versus 31.7% and 24.2% versus 3.3%, respectively. Treatment-related grade 3 to 5 adverse events occurred in 81.5% and 81.7%, respectively. Relative to baseline, pembrolizumab-chemotherapy improved global health status/quality of life scores at week 18 versus placebo-chemotherapy (difference in least squares means = 7.6, 95% CI: 1.5-13.7) and prolonged time to deterioration in cough, chest pain, or dyspnea (HR = 0.50, 95% CI: 0.28-0.89). CONCLUSIONS: Pembrolizumab-chemotherapy prolonged survival versus placebo-chemotherapy with manageable toxicity and preserved or improved health-related quality of life in Chinese patients with metastatic squamous NSCLC. These findings support pembrolizumab-chemotherapy as first-line therapy in this population.

A Prospective, Phase 1 Trial of Nivolumab, Ipilimumab, and Radiotherapy in Patients with Advanced Melanoma.

PURPOSE: Preclinical data suggest that radiotherapy (RT) is beneficial in combination with immune checkpoint blockade. Clinical trials have explored RT with single-agent immune checkpoint blockade, but no trials have reported RT with the combination of nivolumab and ipilimumab. PATIENTS AND METHODS: We conducted a phase 1 study of patients with stage IV melanoma receiving nivolumab and ipilimumab with two different dose-fractionation schemes of RT. Patients had at least one melanoma metastasis that would benefit from palliative RT and one metastasis that would not be irradiated. Nivolumab 1 mg/kg + ipilimumab 3 mg/kg and extracranial RT with a dose of 30 Gy in 10 fractions was administered in Cohort A, and then 27 Gy in 3 fractions was administered in Cohort B. The primary outcome was safety. RESULTS: Twenty patients were treated (10 in each cohort). The rates of treatment-related grade 3-4 adverse events in Cohort A and B were 40% and 30%, respectively. There were no grade ≥3 adverse events attributed to RT. Patients responded to treatment outside of the irradiated volume (Cohort A 5/10; Cohort B 1/9). No evaluable patients had progression of irradiated metastases. Immunologic changes were seen in the peripheral blood with increases in T-cell receptor diversity in some responding patients. CONCLUSIONS: RT with nivolumab and ipilimumab was safe compared with historical data of nivolumab and ipilimumab alone. Immunologic effects were observed in the peripheral blood. Randomized studies are ongoing to assess whether RT increases the efficacy of nivolumab and ipilimumab.

Multicenter phase II study of a combination of cyclosporine a, methotrexate and mycophenolate mofetil for GVHD prophylaxis: results of the Chinese Bone Marrow Transplant Cooperative Group (CBMTCG).

BACKGROUND: Improvement of current GVHD prophylactic therapies remains an important goal in the allo-HSCT. We have described a novel prophylaxis regimen in a single institution trial. The Chinese Bone Marrow Transplant Cooperative Group (CBMTCG) initiated a phase II multicenter study. METHODS: The study was designed as a prospective, single arm phase II open-label, multicenter clinical trial. The primary endpoint was improvement of aGVHD by 25% over historical control (40%) in Chinese patients. 508 patients were enrolled. All of the patients received cyclosporine A (CsA), methotrexate (MTX) and mycophenolate mofetil (MMF) (0.5-1.0 g daily for 30 days) as GVHD prophylaxis regimen. RESULTS: The primary endpoint was met with cumulative incidences of grades 2 to 4 and grades 3 to 4 aGVHD of 23.2% and 10.3%, respectively. Incidence for cGVHD was 67.4%. The non-relapse mortality (NRM) rate was 18.4% at 2 years. The probabilities of leukemia free survival (LFS) for non-advanced stage and advanced stage patients at 2 years were 69.7% and 44.8% respectively (p = 0.000). Recipient age ≥ 40 years, advanced stage and Busulfan-Fludarabine(BuFlu) conditioning regimen were identified as major risk factors for aGVHD. Recipient age ≥ 40 years, BuFlu conditioning regimens, female donor/male recipient and prior aGVHD were associated with cGVHD. Despite lower RM (relapse mortality), patients with grade 2-4 aGVHD had higher NRM and worse OS and LFS compared to patients with grade 0-1 aGVHD. In contrast, patients with cGVHD had better OS and LFS and lower RM compared to patients without cGVHD. CONCLUSION: The novel GVHD regimen decreased the risk for aGVHD by 42% without improving the risk for cGVHD compared to historical controls. Development of aGVHD was associated with worse OS and LFS as well as higher NRM. In contrast, cGVHD was associated with improved OS and LFS likely attributed to a GVL effect.

Oncofetal antigen/immature laminin receptor protein in pregnancy and cancer.

The 37-kDa immature laminin receptor protein (iLRP) is a speciesconserved, universal immunogenic protein that is expressed in all thus-far examined embryonic and early fetal cells of inbred and outbred rodents. It has also been identified in human concepti. It is altered through normal maturation processes to become a non-immunogenic 67-kDa dimeric mature laminin receptor protein (mLRP) in mid-to late gestation in the mammalian fetus. This antigen ceases to be expressed as an active autoimmunogen in the full-term fetus and in the normal differentiating tissues and organs of the neonate or adult organism, apparently due to dimerization, but it is re-expressed as an immunogenic monomer in tumor cells. In this review, we highlight the known mechanisms of immune responses with particular emphasis on the possible role of the 37-kDa oncofetal antigen/immature laminin receptor (OFA/iLRP) in both pregnancy and cancer.

Requirement of TPO/c-mpl for IL-17A-induced granulopoiesis and megakaryopoiesis.

IL-17A is a critical, proinflammatory cytokine essential to host defense and is induced in response to microbial invasion. It stimulates granulopoiesis, leading to neutrophilia, neutrophil activation, and mobilization. TPO synergizes with other cytokines in stimulating and expanding hematopoietic progenitors, also leading to granulopoiesis and megakaryopoiesis, and is required for thrombocytopoiesis. We investigated the effects of in vivo expression of IL-17A on granulopoiesis and megakaryopoiesis in TPO receptor c-mpl-/- mice. IL-17A expression expanded megakaryocytes by 2.5-fold in normal mice but had no such effect in c-mpl-/- mice. The megakaryocyte expansion did not result in increased peripheral platelet counts. IL-17A expression did not impact bone marrow precursors in c-mpl-/- mice; however, it expanded splenic precursors, although to a lesser extent compared with normal controls (CFU-HPP). No peripheral neutrophil expansion was observed in c-mpl-/- mice. Moreover, in c-mpl-/- mice, release of IL-17A downstream cytokines was reduced significantly (KC, MIP-2, GM-CSF). The data suggest that IL-17A requires the presence of functional TPO/c-mpl to exert its effects on granulopoiesis and megakaryopoiesis. Furthermore, IL-17A and its downstream cytokines are important regulators and synergistic factors for the physiologic function of TPO/c-mpl on hematopoiesis.

A phase 2 randomized trial of paclitaxel and carboplatin with or without panitumumab for first-line treatment of advanced non-small-cell lung cancer.

INTRODUCTION: This two-part phase 2 study evaluated the efficacy and safety of panitumumab, a fully human anti-epidermal growth factor receptor monoclonal antibody, combined with carboplatin/paclitaxel in patients with previously untreated advanced non-small-cell lung cancer. METHODS: In part 1, patients were sequentially enrolled to receive paclitaxel 200 mg/m(2) and carboplatin (area under the concentration-versus-time curve, 6 mg/min/ml) plus panitumumab (1.0, 2.0, or 2.5 mg/kg). In part 2, patients were randomized 2:1 to receive paclitaxel/carboplatin with (arm A) or without (arm B) the maximum tolerated dose of panitumumab identified in part 1. Primary endpoints in parts 1 and 2 were the incidence of dose-limiting toxicities and time to progression (TTP), respectively. RESULTS: In part 1, four of 19 patients had dose-limiting toxicities: three at 2.0 mg/kg (fatigue, pain in extremity, dyspepsia) and one at 2.5 mg/kg (rash). The maximum tolerated dose was not reached; panitumumab 2.5 mg/kg was selected for part 2. In part 2, TTP was 18.1 weeks (95% confidence interval [CI], 13.6-23.3) in arm A and 23.0 weeks (95% CI, 15.9-24.1) in arm B (hazard ratio, 0.9; 90% CI, 0.66-1.21; p = 0.555). Progression-free survival in arms A and B was 17.6 weeks and 18.3 weeks, respectively, and the objective response rate was 15.2% and 11.1%. Adverse events occurring more frequently in arm A than in arm B included skin toxicity, diarrhea, stomatitis, vomiting, and dizziness. Exploratory analyses did not demonstrate associations between potential biomarkers and outcomes. CONCLUSION: Although toxicity was predictable and manageable, the addition of panitumumab to paclitaxel/carboplatin did not improve TTP in patients with previously untreated advanced non-small-cell lung cancer.

Experimental chronic hepatitis B infection of neonatal tree shrews (Tupaia belangeri chinensis): a model to study molecular causes for susceptibility and disease progression to chronic hepatitis in humans.

BACKGROUND: Hepatitis B virus (HBV) infection continues to be an escalating global health problem. Feasible and effective animal models for HBV infection are the prerequisite for developing novel therapies for this disease. The tree shrew (Tupaia) is a small animal species evolutionary closely related to humans, and thus is permissive to certain human viral pathogens. Whether tree shrews could be chronically infected with HBV in vivo has been controversial for decades. Most published research has been reported on adult tree shrews, and only small numbers of HBV infected newborn tree shrews had been observed over short time periods. We investigated susceptibility of newborn tree shrews to experimental HBV infection as well as viral clearance over a protracted time period. RESULTS: Forty-six newborn tree shrews were inoculated with the sera from HBV-infected patients or tree shrews. Serum and liver samples of the inoculated animals were periodically collected and analyzed using fluorescence quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, Southern blot, and immunohistochemistry. Six tree shrews were confirmed and four were suspected as chronically HBV-infected for more than 48 (up to 228) weeks after inoculation, including three that had been inoculated with serum from a confirmed HBV-infected tree shrew. CONCLUSIONS: Outbred neonatal tree shrews can be long-term chronically infected with HBV at a frequency comparable to humans. The model resembles human disease where also a smaller proportion of infected individuals develop chronic HBV related disease. This model might enable genetic and immunologic investigations which would allow determination of underlying molecular causes favoring susceptibility for chronic HBV infection and disease establishment vs. viral clearance.

Dose escalation of once weekly oral vinorelbine concurrent with weekly split dose hypofractionated chest radiation for palliation of advanced non-small cell lung cancer: a phase I/II study.

INTRODUCTION: Daily chest radiation schedules can be cumbersome for some patients and could also delay the administration of higher, systemic doses of chemotherapy. METHODS: Thirty-six patients with advanced non-small cell lung cancer (stages IIIB and IV) were treated using a once weekly hypofractionated chest irradiation schedule (5 Gy divided in 2 fractions 6 hours apart × 12 weeks), concurrently with escalating doses of oral vinorelbine. RESULTS: The maximum tolerated dose of vinorelbine was 80 mg/m; 28 patients were treated at 70 mg/m(2). Dose-limiting toxicity was hematopoietic. A mean of 8.5 cycles per patient was administered, with 53% receiving all 12 cycles. Median overall survival was 9.9 months (95% confidence interval, 5.6-14.2 months). Within the radiation field, 1 patient (4%) had a complete response, 13 (54%) a partial response, and 10 (42%) had stable disease. Nine patients could be assessed for disease outside the radiation field, of whom 7 had stable disease and 2 progressed. CONCLUSIONS: Weekly, hypofractionated chest radiation is well tolerated and can be administered safely concurrently with vinorelbine at systemic doses. This simplified, convenient regimen could benefit patients in need for both local and systemic palliation.

IL-17 is a potent synergistic factor with GM-CSF in mice in stimulating myelopoiesis, dendritic cell expansion, proliferation, and functional enhancement.

OBJECTIVE: Interleukin (IL)-17, which now defines the Th(17) immune response, is a critical cytokine expressed and required for stress granulopoiesis during microbial invasion. Dendritic cells (DC) can instigate this response by inducing IL-17 expression in CD4(+) T cells. Besides IL-17, microbial invasion also stimulates production of the DC growth factor granulocyte-macrophage colony-stimulating factor (GM-CSF). The objective was the in vitro and in vivo investigation of IL-17 on DC proliferation and function in mice. MATERIALS AND METHODS: Murine IL-17 (mIL-7) or murine GM-CSF (mGM-CSF), or both, was expressed in C57BL6 mice using adenoviral technology to assess hematopoietic and DC changes. The E-22 tymoma tumor cell line using a previously described vaccinia virus ovalbumin/LacZ murine tumor model was employed to study effects on tumor rejection. RESULTS: The combination of mIL-17 and mGM-CSF increased peripheral neutrophila by 28-fold and splenic colonies by 11- and 14-fold over each individual factor in mice, respectively. The effect of mIL-17 by itself on murine DCs in vitro and in vivo was minimal; however, the combination greatly enhanced the stimulating effects of mGM-CSF, increasing the total numbers of CD14b/c(+) spleen DC by fourfold, as well as their function measured by enhanced endocytosis. Mixed lymphocyte reactions using mIL-17/mGM-CSF cultured DCs stimulator cells enhanced lymphocyte responses by twofold over mGM-CSF alone. Vaccination against LacZ in the C57BL6 E22 syngenic thymoma tumor model effectively delayed tumor growth in animals pretreated with the mIL-17/mGM-CSF combination prior to vaccination. CONCLUSIONS: mIL-17 effectively synergizes with mGM-CSF in stimulating granulopoiesis and DC expansion, as well as in functional enhancement of DCs.

Targeted agents for chronic myelogenous leukemia: will that be the end of allogeneic bone marrow transplantation for that disease?

Although the drug imatinib has been accepted as the treatment of choice for chronic myelogenous leukemia (CML) in chronic phase (CP) throughout the Western world, allogeneic stem cell transplantation (allo-SCT) continues to remain a widely practiced first-line treatment in countries with limited health care budgets. The rationale is not scientific, but largely economically based. We analyzed a cohort of 46 CML patients who participated in a graft-versus-host disease (GVHD) prophylaxis clinical trial and underwent related HLA-matched allogeneic peripheral blood stem cell transplantation. The median time of follow-up in surviving patients was 43 months (range: 4-89 months). Risk stratification of the population was done by European Blood and Marrow Transplant (EBMT) criteria. The estimated probabilities of overall survival (OS) and leukemia-free survival (LFS) at 3 years in low EBMT risk score (0-2) patients were both 91%, respectively. We conclude that in countries with restricted access to imatinib, allo-SCT should be considered early on as front-line therapy. Continued research support for bone marrow transplantation will be needed to make a global impact on this disease.

Production, safety and antitumor efficacy of recombinant Oncofetal Antigen/immature laminin receptor protein.

We describe here for the first time an efficient high yield production method for clinical grade recombinant human Oncofetal Antigen/immature laminin receptor protein (OFA/iLRP). We also demonstrate significant antitumor activity for this protein when administered in liposomal delivery form in a murine model of syngeneic fibrosarcoma. OFA/iLRP is a therapeutically very promising universal tumor antigen that is expressed in all mammalian solid tumors tested so far. We have cloned the human OFA/iLRP cDNA in a bacterial expression plasmid which incorporates a 6x HIS-tag. Large scale cultures of the plasmid transformed Escherichia coli were performed and the crude HIS-tagged OFA/iLRP was isolated as inclusion bodies and solubilized in guanidine chloride. The protein was then purified by successive passage through three column chromatography steps of immobilized metal affinity, anion exchange, and gel filtration. The resulting protein was 94% pure and practically devoid of endotoxin and host cell protein. The purified OFA/iLRP was tested in mice for safety and efficacy in tumor rejection with satisfactory results. This protein will be used for loading onto autologous dendritic cells in an FDA approved phase I/II human cancer vaccine trial in OFA/iLRP-positive breast cancer patients.

Biochemical characterization of riboflavin carrier protein (RCP) in prostate cancer.

Riboflavin carrier protein (RCP) is a growth- and development-specific protein. Here, we characterized the expression of this protein in prostate cancer by polyclonal and monoclonal antibodies against chicken RCP. RCP was localized to both androgen-dependent and independent prostate cancer cell lines. Compared to controls, RCP was over-expressed in all 45 prostate adenocarcinomas, irrespective of the Gleason's score or the stage of the disease. The identified RCP had a molecular weight of 38 kDa, similar to RCP purified from chicken. Presence of this protein was also confirmed by siRNA inhibition analysis. Antibodies to chicken RCP inhibited incorporation of tritiated thymidine into DNA and prevented riboflavin uptake in PC3 prostate cancer cells, suggesting a critical function of this protein in prostate cancer cell growth. These data suggest that RCP can be used as a tumor biomarker in prostate cancer.

IL-17F/IL-17R interaction stimulates granulopoiesis in mice.

OBJECTIVE: IL-17F, a member of the interleukin (IL)-17 cytokine family, most closely resembles IL-17A structurally. IL-17A is a potent stimulator of granulopoiesis; its expression is induced in response to microbial challenge. Although IL-17F is considered to be a weak IL-17A analog that is also mediating its effect via IL-17R, its exact role and in vivo functions are unknown. Our goal was to determine the in vivo activity of IL-17F on granulopoiesis as well as on release of granulopoiesis-stimulating downstream cytokines in mice and directly compare its effect to IL-17A. MATERIALS AND METHODS: Murine IL-17A (mIL-17A) or IL-17F (mIL-17F) was expressed in vivo in C57BL6 mice using adenoviral gene transfer technology. Peripheral cell counts were assessed as well as hematopoietic precursors using colony-forming assays at set time points. Downstream cytokines were measured using enzyme-linked immunosorbent assay and reverse transcriptase polymerase chain reaction. RESULTS: We found mIL-17F to have similar expression kinetics as mIL-17A in splenocytes in vitro and in vivo, following challenge with microbial agents. Overexpression of mIL-17F in vivo resulted in similar neutrophilia and only in slightly reduced myeloid progenitor expansion when compared to mIL-17A. In vivo, there was no difference in releases for granulocyte-macrophage colony-stimulating factor; regulated on activation, normal T expressed and secreted; interferon-inducible protein-10; IL-6; and monocyte chemotactic protein-1 between either cytokine. IL-1A, macrophage inflammatory protein -2 (MIP), KC, and granulocyte colony-stimulating factor expression was approximately half of that seen with mIL-17A. CONCLUSION: Both IL-17A and IL-17F are induced by similar stimuli, have similar expression kinetics and despite only minimal in vitro activity for IL-17F, surprisingly they exert similar in vivo bioactivity. IL-17F bioactivity appears to be augmented in vivo through mechanisms that require further investigation.

Phase I study of flavopiridol in combination with Paclitaxel and Carboplatin in patients with non-small-cell lung cancer.

PURPOSE: The aim of this study was to evaluate the safety and tolerability of escalating doses of flavopiridol/ paclitaxel/carboplatin in patients with advanced-stage non-small-cell lung cancer (NSCLC) as well as the pharmacokinetics and activity of flavopiridol when used in combination with paclitaxel/carboplatin. PATIENTS AND METHODS: Eligible patients aged 18-75 years with previously untreated stage IIIB/IV NSCLC received paclitaxel 175 mg/m2 over 3 hours followed by carboplatin area under the curve (AUC) 5 over 1 hour and flavopiridol 30-85 mg/m2 over 24 hours every 3 weeks for 3 cycles. RESULTS: Eighteen patients were enrolled at 4 sites in the United States and received flavopiridol 30 mg/m2 (n = 3), 50 mg/m2 (n = 6), 70 mg/m2 (n = 3), or 85 mg/m2 (n = 6). No dose-limiting toxicities (DLTs) occurred at the 50-mg/m2 or 70-mg/m2 dose levels. Two patients treated at the 85-mg/m2 dose level experienced cardiovascular events that did not meet the criteria for DLT but were fatal in 1 case, prompting no further flavopiridol dose escalations and establishment of 70 mg/m2 as the maximum tolerated dose. The most frequently reported adverse events across all dose levels combined were nausea (89%), asthenia (67%), and diarrhea (56%). Flavopiridol concentrations increased rapidly, reached a plateau, and showed a multiphasic decline after the 24-hour infusion. Of 12 patients evaluable for efficacy, 8 achieved a partial response, and 4 had stable disease. CONCLUSION: Flavopiridol in doses