Evaluation of Aminopolycarboxylate Chelators for Whole-Body Clearance of Free 225Ac: A Feasibility Study to Reduce Unexpected Radiation Exposure during Targeted Alpha Therapy.

Actinium-225 (225Ac) is a promising radionuclide used in targeted alpha therapy (TAT). Although 225Ac labeling of bifunctional chelating ligands is effective, previous in vivo studies reported that free 225Ac can be released from the drugs and that such free 225Ac is predominantly accumulated in the liver and could cause unexpected toxicity. To accelerate the clinical development of 225Ac TAT with a variety of drugs, preparing methods to deal with any unexpected toxicity would be valuable. The aim of this study was to evaluate the feasibility of various chelators for reducing and excreting free 225Ac and compare their chemical structures. Nine candidate chelators (D-penicillamine, dimercaprol, Ca-DTPA, Ca-EDTA, CyDTA, GEDTA TTHA, Ca-TTHA, and DO3A) were evaluated in vitro and in vivo. The biodistribution and dosimetry of free 225Ac were examined in mice before an in vivo chelating study. The liver exhibited pronounced 225Ac uptake, with an estimated human absorbed dose of 4.76 SvRBE5/MBq. Aminopolycarboxylate chelators with five and six carboxylic groups, Ca-DTPA and Ca-TTHA, significantly reduced 225Ac retention in the liver (22% and 30%, respectively). Significant 225Ac reductions were observed in the heart and remainder of the body with both Ca-DTPA and Ca-TTHA, and in the lung, kidney, and spleen with Ca-TTHA. In vitro interaction analysis supported the in vivo reduction ability of Ca-DTPA and Ca-TTHA. In conclusion, aminopolycarboxylate chelators with five and six carboxylic groups, Ca-DTPA and Ca-TTHA, were effective for whole-body clearance of free 225Ac. This feasibility study provides useful information for reducing undesirable radiation exposure from free 225Ac.

Ramucirumab as second-line treatment in patients with advanced hepatocellular carcinoma: Japanese subgroup analysis of the REACH trial.

BACKGROUND: REACH evaluated ramucirumab in the second-line treatment of patients with advanced hepatocellular carcinoma. In the intent-to-treat population (n = 565), a significant improvement in overall survival (OS) was not observed. In patients with an elevated baseline α-fetoprotein (AFP) level (400 ng/mL or greater), an improvement in OS was demonstrated. An analysis of the Japanese patients in REACH was performed. METHODS: An analysis was performed with the subset of the intent-to-treat population enrolled in Japan (n = 93). RESULTS: The median OS was 12.9 months for the ramucirumab arm (n = 45) and 8.0 months for the placebo arm (n = 48) [hazard ratio (HR) 0.621 (95 % confidence interval (CI) 0.391-0.986); P = 0.0416]. The median progression-free survival was 4.1 months for the ramucirumab arm and 1.7 months for the placebo arm [HR 0.449 (95 % CI 0.285-0.706); P = 0.0004]. The objective response rates were 11 % for the ramucirumab arm and 2 % for the placebo arm (P = 0.0817). The grade 3 or higher treatment-emergent adverse events occurring in more than 5 % of patients with a higher incidence for the ramucirumab arm (n = 44) than for the placebo arm (n = 47) were ascites (7% vs 2 %), hypertension (7 % vs 2 %), and cholangitis (7 % vs 0 %). In patients with a baseline AFP level of 400 ng/mL or greater, the median OS was 12.9 months for the ramucirumab arm (n = 20) and 4.3 months for the placebo arm (n = 22) [HR 0.464 (95 % CI 0.232-0.926); P = 0.0263]. CONCLUSIONS: In the Japanese patients in REACH, ramucirumab treatment improved OS, including in patients with a baseline AFP level of 400 ng/mL or greater; improvements in progression-free survival and objective response rate were also demonstrated. The safety profile of ramucirumab was acceptable and well tolerated in Japanese patients. ClinicalTrials.gov identifier NCT01140347.

Japanese Society of Clinical Oncology clinical practice guidelines 2010 for antiemesis in oncology: executive summary.

The purpose of this article is to disseminate the standard of antiemetic therapy for Japanese clinical oncologists. On the basis of the Appraisal of Guidelines for Research and Evaluation II instrument, which reflects evidence-based clinical practice guidelines, a working group of the Japanese Society of Clinical Oncology (JSCO) reviewed clinical practice guidelines for antiemesis and performed a systematic review of evidence-based domestic practice guidelines for antiemetic therapy in Japan. In addition, because health-insurance systems in Japan are different from those in other countries, a consensus was reached regarding standard treatments for chemotherapy that induce nausea and vomiting. Current evidence was collected by use of MEDLINE, from materials from meetings of the American Society of Clinical Oncology National Comprehensive Cancer Network, and from European Society of Medical Oncology/Multinational Association of Supportive Care in Cancer guidelines for antiemesis. Initially, 21 clinical questions (CQ) were selected on the basis of CQs from other guidelines. Patients treated with highly emetic agents should receive a serotonin (5-hydroxytryptamine; 5HT3) receptor antagonist, dexamethasone, and a neurokinin 1 receptor antagonist. For patients with moderate emetic risk, 5HT3 receptor antagonists and dexamethasone were recommended, whereas for those receiving chemotherapy with low emetic risk dexamethasone only is recommended. Patients receiving high-emetic-risk radiation therapy should also receive a 5HT3 receptor antagonist. In this paper the 2010 JSCO clinical practice guidelines for antiemesis are presented in English; they reveal high concordance of Japanese medical circumstances with other antiemetic guidelines that are similarly based on evidence.

Impact of the first tumor response at eight weeks on overall survival in metastatic breast cancer patients treated with first-line combination chemotherapy.

The aim of this was to determine whether the change of size observed at the first response evaluation after initiation of first-line combination chemotherapy correlates with overall survival (OS) in patients with metastatic breast cancer (MBC). The change in size of tumors derived from measurements according to Response Evaluation Criteria In Solid Tumors (RECIST) at the first evaluation on computed tomography (CT) was obtained from a multicenter, randomized phase III trial ("TEX trial," n = 287) comparing treatment with a combination of epirubicin and paclitaxel alone or with capecitabine (TEX). Cox regression and Kaplan-Meier analyses were performed to evaluate the correlations between the first change in tumor size, response according to RECIST and OS. Data from CT evaluations of 233 patients were available. Appearance of new lesions or progression of non-target lesions (new/non-target) indicated short OS by univariable regression analysis (HR 3.76, 95 % CI 1.90-7.42, p < 0.001). A decrease by >30 % at this early time point was prognostic favorable (HR 0.69, 95 % CI 0.49-0.98, p = 0.04) and not significantly less than the best overall response according to RECIST. After adjustment for previous adjuvant treatment and the treatment given within the frame of the randomized trial, OS was still significantly shorter in patients with new/non-target lesions after a median 8 weeks of treatment (HR 4.41, 95 % CI 2.74-7.11, p < 0.001). Disease progression at the first evaluation correlates with OS in patients with MBC treated with first-line combination chemotherapy. The main reason for early disease progression was the appearance of new lesions or progression of non-target lesions. These patients had poor OS even though more lines of treatment were available. Thus, these factors should be focused on in the response evaluations besides tumor size changes.

A phase II study of biweekly mitomycin C and irinotecan combination therapy in patients with fluoropyrimidine-resistant advanced gastric cancer: a report from the Gastrointestinal Oncology Group of the Japan Clinical Oncology Group (JCOG0109-DI Trial).

BACKGROUND: Preclinical studies have shown that mitomycin C (MMC) acts synergistically with irinotecan (CPT-11). In this phase II study, we evaluated the efficacy and toxicity of MMC/CPT-11 therapy as second-line chemotherapy for patients with fluoropyrimidine-resistant advanced gastric cancer. METHODS: Eligible patients had evidence of tumor progression despite prior treatment with fluoropyrimidine-based regimens or had relapsed within 6 months after completion of therapy with adjuvant fluoropyrimidines. Treatment consisted of MMC (5 mg/m(2)) and CPT-11 (150 mg/m(2)) administered i.v. every 2 weeks. The primary endpoint was the response rate (RR). Our hypothesis was that this combination therapy was efficacious when the lower boundary of the 95% confidence interval (CI) of the RR exceeded 20% of the threshold RR. RESULTS: Between April 2002 and July 2003, 45 eligible patients were registered and analyzed. Among the 45 patients, 40 (89%) had previously received chemotherapy for metastasis and 24 (53%) had a performance status (PS) of 0. Thirteen partial responses were obtained among the 45 patients, resulting in an overall RR of 29% (95% CI, 16-42%). The median time to progression was 4.1 months, and the median survival time was 10 months, with a 1-year survival rate of 36%. Grade 4 neutropenia was observed in 29% of the patients, whereas febrile neutropenia occurred in 9%. The incidence rates of grade 3 nausea and diarrhea were 13 and 2%, respectively. CONCLUSIONS: Although this study did not achieve the per-protocol definition of activity, the progression-free survival and overall survival appeared to be promising, with acceptable tolerability. Thus, MMC/CPT-11 therapy as second-line chemotherapy for fluoropyrimidine-resistant advanced gastric cancer presents a potential treatment option in patients with a good PS.