Phase I study of PF-03446962, a fully human monoclonal antibody against activin receptor-like kinase-1, in patients with hepatocellular carcinoma.

BACKGROUND: This expansion cohort of a multicenter, dose-escalation, phase I study (NCT00557856) evaluated safety, tolerability, antitumor activity, pharmacokinetics, and pharmacodynamic effects of the anti-activin receptor-like kinase-1 (ALK-1) monoclonal antibody PF-03446962 in advanced hepatocellular carcinoma (HCC). PATIENTS AND METHODS: Patients with HCC and disease progression after prior antiangiogenic therapy or intolerance to treatment received PF-03446962 7 mg/kg intravenously biweekly, as recommended in the dose-escalation part of the study. RESULTS: Twenty-four patients received PF-03446962. The most frequent treatment-related adverse events (AEs) were thrombocytopenia (33.3%), asthenia (29.2), and chills (16.7%). Two patients experienced treatment-related telangiectasia, suggesting an in vivo knockout of ALK-1 function through ALK-1 pathway inhibition. Overall, treatment-related grade 3-4 AEs were reported in eight patients (33.3%). Treatment-related grade 3-4 thrombocytopenia was noted in four patients. No complete or partial responses were reported. Twelve (50%) patients achieved stable disease, which lasted ≥12 weeks in seven (29.2%) patients. The median time to progression was 3 months. Biomarker analyses showed higher mean tumor expression of c-tumor mesenchymal-epithelial transition factor and higher mean serum levels of bone morphogenetic protein-9 in patients with disease control (DC) for ≥12 weeks versus patients with disease progression. Conversely, lower mean serum transforming growth factor-ß and vascular endothelial growth factor receptor-3 levels were detected in patients with DC versus patients with progression. CONCLUSIONS: The observed safety, tolerability, pharmacokinetic profile, and clinical activity support further evaluation of PF-03446962 in patients with HCC and other solid malignancies, as single agent or in combination with other antiangiogenic, chemotherapeutic, or immunotherapeutic agents. TRIAL REGISTRATION NUMBER: NCT00557856.

A first-in-human study of the anti-α5ß1 integrin monoclonal antibody PF-04605412 administered intravenously to patients with advanced solid tumors.

PURPOSE: A first-in-human clinical trial of a fully human, Fc-engineered IgG1 monoclonal antibody targeting integrin α5ß1 was conducted to evaluate tolerability, maximum tolerated dose, pharmacokinetics, pharmacodynamics and preliminary anti-tumor activity. METHODS: Escalating doses of PF-04605412 were given IV on day 1, 28 and every 2 weeks thereafter to patients with advanced solid tumors until disease progression or unacceptable toxicity. Sequential dose cohorts were evaluated based on a modified 3 + 3 dose-escalation design. The starting dose was 7.5 mg based on preclinical data. RESULTS: Thirty-three patients were enrolled to six dose levels (7.5, 11.25, 16.9, 34, 68 and 136 mg). Twenty-three patients were evaluable for the primary endpoint (determination of the maximum tolerated dose). Five patients required permanent drug discontinuation due to acute infusion-related reactions, which occurred as grade 3 events in two patients. PK analysis indicated that the targeted drug exposure based on preclinical models was not achieved by the tolerated doses and PK modeling suggesting that doses at least fivefold higher would be necessary. No anti-tumor activity was observed. CONCLUSION: Based on the safety data, the risks associated with the likelihood of significant cytokine-mediated infusion reactions at higher doses, the projected high dose necessary to affect on the biological target and the lack of anti-tumor activity at the doses explored, the trial was prematurely terminated without determining a formal maximum tolerated dose. Further clinical development of PF-04605412 has been discontinued.

Effects of the tumor vasculature targeting agent NGR-TNF on the tumor microenvironment in murine lymphomas.

TNF-alpha may improve drug delivery to tumors by alteration of vascular permeability. However, toxicity precludes its systemic administration in patients. NGR-TNF comprises TNF coupled to the peptide CNGRC, which is a ligand for CD13. CD13 is expressed on tumor vasculature. Therefore, to assess the efficacy of NGR-TNF its biological effect on tumor vasculature should be measured rather than its effect on tumor growth. The aim of this study was to assess the effects of a low dose of NGR-TNF (5 ng/kg) on vascular permeability, tumor hypoxia, perfusion and proliferation in lymphoma bearing mice. MRI measurements with blood pool contrast agent showed an increased leakage of the contrast agent from the vasculature in NGR-TNF treated tumors compared with controls (p < 0.05), suggesting NGR-TNF-induced vascular permeability. Immunohistochemical analysis two hours after NGR-TNF treatment showed a decrease in tumor hypoxia (p < 0.1) and an increase in labeling index of the S-phase marker bromodeoxyuridine (p < 0.1), possibly due to an increase in tumor blood flow after NGR-TNF treatment. Although a decrease in tumor hypoxia and an increase in labeling index could have lead to increased tumor growth, in this experiment after one day a decrease in tumor volume was measured. Possibly, the effects on tumor hypoxia and proliferation two hours after treatment are transient and overruled by other, more longlasting effects. For example, the observed increase in vascular permeability may lead to haemoconcentration and increased interstitial pressure, ultimately resulting in an reduction of tumor blood flow and thus a decrease in tumor growth. A beneficial effect of NGR-TNF in combination with other therapeutical agents may therefore critically depend on the sequence and timing of the regimens. Currently, NGR-TNF is being tested in clinical studies.

Modulation of GvHD by suicide-gene transduced donor T lymphocytes: clinical applications in mismatched transplantation.

In allogeneic hematopoietic cell transplantation (allo-HCT), donor lymphocytes play a central therapeutic role in both GvL and immune reconstitution. However, the full exploitation of these therapeutic properties is limited by the occurrence of GvHD. Different strategies have been investigated to obtain all the benefits derived from donor lymphocytes while avoiding the risk of GvHD. The genetic engineering of donor lymphocytes with the herpes simplex virus-thymidine kinase (HSV-TK) suicide gene confers the ability to modulate GvHD by invivo ganciclovir-induced elimination of the transduced cells. The suicide-gene strategy has applications in both donor lymphocyte infusion (DLI) for disease relapse and in add-back infusions after T-cell depleted allo-HCT. TK cell DLI resulted in anti-tumor activity in a relevant proportion of treated patients. Haplo-identical stem cell transplantation (haplo-HCT) is a promising therapeutic option for patients with high risk hematologic malignancies lacking an HLA-matched donor. However, the profound T-cell depletion required to overcome the risk of lethal GvHD has been associated with a marked delayed T-cell recovery with a prolonged risk of post-transplant viral, fungal and other opportunistic infections. TK cell add-backs efficiently promote early immune reconstitution after haplo-HCT and prevent disease relapse, providing a unique tool for the control of GvHD. The genetic manipulation of donor lymphocytes with a suicide gene is a promising strategy to increase feasibility and safety of allo-HCT.

Doxifluridine as palliative treatment in advanced gastric and pancreatic cancer patients.

BACKGROUND: The association of 5-fluorouracil (5-FU) and leucovorin is currently the most used combination in the treatment of advanced gastrointestinal neoplasms. Doxifluridine (d-FUR) is a fluoropyrimidine derivative that is converted into 5-FU inside tumor cells, where it is selectively cytotoxic. The oral administration of dFUR has been extensively investigated in colorectal carcinoma, and has been proven to be active and well tolerated. The purpose of this study was to test the effectiveness of the oral combination with dFUR plus l-leucovorin in gastric and pancreatic cancer patients. METHODS: A total of 50 cases were treated with l-leucovorin 25 mg, followed 2 h later by d-FUR 1,200 mg/m2 for 5 days; the cycles were repeated every 10 days. The regimen was given for a maximum of 36 cycles or until disease progression. Twenty-six patients had gastric cancer (all of whom were pretreated with polychemotherapy) and 24 had advanced pancreatic carcinoma. RESULTS: Objective responses were obtained in 4 (15%; 95% Cl 1-29) patients with gastric cancer, and in 1 (4%) with pancreatic cancer. The median response duration was 4 months. All of the responses were seen in patients previously treated with 5-FU-containing regimens. The median survival in gastric cancer patients was 7 months. Toxicity was moderate: WHO grade III and IV diarrhea was observed in 14% of the cases. CONCLUSIONS: This study indicates the efficacy of oral d-FUR plus l-leucovorin as palliative treatment in gastric cancer patients. The results in pancreatic carcinoma are disappointing but are in line with the published data relating to fluoropyrimidines.

Antihypertensive and metabolic effects of nitrendipine in hypertensive diabetic patients.

The subjects were 15 patients, aged 53 to 74 years, with noninsulin-dependent diabetes mellitus and mild to moderate hypertension. Each received 20 to 40 mg of nitrendipine daily for six months. Mean supine blood pressures decreased significantly from 177/102 mmHg before treatment to 164/95 mmHg at three months and continued to decline during the following three months. Diastolic blood pressure was reduced to less than 90 mmHg in eight of the 15 patients. No changes in heart rate, glycemic control (serum levels of glucose, C-peptide, glycosylated hemoglobin, and fructosamine), or serum lipid levels (cholesterol and its lipoprotein fractions, triglycerides, and apolipoproteins A1 and B) were noted. It is concluded that nitrendipine is safe and effective in the treatment of hypertension in diabetic patients.