Antitumor activities of a novel 9-aminoanthracycline (SM-5887) against mouse experimental tumors and human tumor xenografts

Carbohydrate-based drugs launched during 2000-2021

Carbohydrates are fundamental molecules involved in nearly all aspects of lives, such as being involved in formating the genetic and energy materials, supporting the structure of organisms, constituting invasion and host defense systems, and forming antibiotics secondary metabolites. The naturally occurring carbohydrates and their derivatives have been extensively studied as therapeutic agents for the treatment of various diseases. During 2000 to 2021, totally 54 carbohydrate-based drugs which contain carbohydrate moities as the major structural units have been approved as drugs or diagnostic agents. Here we provide a comprehensive review on the chemical structures, activities, and clinical trial results of these carbohydrate-based drugs, which are categorized by their indications into antiviral drugs, antibacterial/antiparasitic drugs, anticancer drugs, antidiabetics drugs, cardiovascular drugs, nervous system drugs, and other agents.

Novel Anthracycline Utorubicin for Cancer Therapy

Novel anticancer compounds and their precision delivery systems are actively developed to create potent and well-tolerated anticancer therapeutics. Here, we report the synthesis of a novel anthracycline, Utorubicin (UTO), and its preclinical development as an anticancer payload for nanocarriers. Free UTO was significantly more toxic to cultured tumor cell lines than the clinically used anthracycline, doxorubicin. Nanoformulated UTO, encapsulated in polymeric nanovesicles (polymersomes, PS), reduced the viability of cultured malignant cells and this effect was potentiated by functionalization with a tumor-penetrating peptide (TPP). Systemic peptide-guided PS showed preferential accumulation in triple-negative breast tumor xenografts implanted in mice. At the same systemic UTO dose, the highest UTO accumulation in tumor tissue was seen for the TPP-targeted PS, followed by nontargeted PS, and free doxorubicin. Our study suggests potential applications for UTO in the treatment of malignant diseases and encourages further preclinical and clinical studies on UTO as a nanocarrier payload for precision cancer therapy.

Novel Anthracycline Utorubicin for Cancer Therapy

Novel anticancer compounds and their precision delivery systems are actively developed to create potent and well-tolerated anticancer therapeutics. Here, we report the synthesis of a novel anthracycline, Utorubicin (UTO), and its preclinical development as an anticancer payload for nanocarriers. Free UTO was significantly more toxic to cultured tumor cell lines than the clinically used anthracycline, doxorubicin. Nanoformulated UTO, encapsulated in polymeric nanovesicles (polymersomes, PS), reduced the viability of cultured malignant cells and this effect was potentiated by functionalization with a tumor-penetrating peptide (TPP). Systemic peptide-guided PS showed preferential accumulation in triple-negative breast tumor xenografts implanted in mice. At the same systemic UTO dose, the highest UTO accumulation in tumor tissue was seen for the TPP-targeted PS, followed by nontargeted PS, and free doxorubicin. Our study suggests potential applications for UTO in the treatment of malignant diseases and encourages further preclinical and clinical studies on UTO as a nanocarrier payload for precision cancer therapy.

Impact of Amrubicin Monotherapy as Second-Line Chemotherapy on Outcomes in Elderly Patients with Relapsed Extensive-Disease Small-Cell Lung Cancer

Purpose

Amrubicin (AMR) is an anticancer drug for patients with relapsed small-cell lung cancer (SCLC). However, the efficacy of AMR in elderly patients with relapsed SCLC after chemotherapy by carboplatin plus etoposide (CE) has not been sufficiently evaluated.

Patients and Methods

The medical records of patients with relapsed SCLC who received AMR as second-line chemotherapy were retrospectively reviewed, and their treatment outcomes were evaluated.

Results

Forty-one patients with a median age of 76 years were analyzed. The overall response rate was 26.8%. Median progression-free survival (PFS) and overall survival (OS) were 3.5 and 8.1 months, respectively. While the median PFS of 4.7 and 2.8 months in the sensitive relapse and the refractory relapse group differed significantly (P=0.043), respectively, the median OS of 10.7 and 6.8 months in the respective relapse groups did not indicate a statistically significant difference (P=0.24). The median PFS in a group with a modified Glasgow prognostic score (mGPS) of 0 and a group with a mGPS 1 or 2 were 4.5 and 1.6 months (P=0.052), respectively, and the median OS in the respective mGPS groups were 10.7 and 4.4 months (P=0.034). Multivariate analysis identified good performance status, limited disease, and mGPS 0 as favorable independent predictors of PFS and OS of AMR monotherapy. Grade 3 or higher neutropenia was observed in 23 patients (56%), and febrile neutropenia was observed in nine patients (22%). Non-hematological toxic effects were relatively mild, and pneumonitis and treatment-related deaths were not observed.

Conclusion

AMR is an effective and feasible regimen for elderly patients with relapsed SCLC after CE therapy.

Amrubicin monotherapy for elderly patients with relapsed extensive-disease small-cell lung cancer: A retrospective study

Background

Previous studies have shown amrubicin (AMR) to be an effective second‐line treatment option for small‐cell lung cancer (SCLC). However, the efficacy of AMR in elderly patients with relapsed SCLC has not been sufficiently evaluated.

Methods

The medical records of elderly patients with relapsed SCLC who received AMR as second‐line chemotherapy were retrospectively reviewed, and their treatment outcomes were evaluated.

Results

Thirty‐one patients with a median age of 72 years (22 patients with sensitive relapse and 9 with refractory relapse) were analyzed. The median number of treatment cycles was four (range: 1–10), and the response rate was 29%. The median progression‐free survival (PFS) and overall survival (OS) were 5.4 and 11.6 months, respectively. The OS of 22 patients who received third‐line chemotherapy was 15.5 months. The PFS (6.2 vs. 3.2 months; P = 0.002) and OS (14.8 vs. 5.7 months; P = 0.004) were significantly longer in patients with sensitive relapse than those with refractory relapse. The frequency of grade 3 or higher neutropenia was high (n = 18, 58%), while febrile neutropenia was only observed in five patients (16%). Non‐hematological toxic effects were relatively mild, and pneumonitis and treatment‐related deaths were not observed.

Conclusion

AMR may be a feasible and effective regimen for elderly patients with relapsed SCLC.

Comparison of carboplatin plus etoposide with amrubicin monotherapy for extensive-disease small cell lung cancer in the elderly and patients with poor performance status

BACKGROUND

Carboplatin plus etoposide (CE) is a standard treatment for elderly patients with extensive-disease small cell lung cancer (ED-SCLC). However, amrubicin monotherapy (AMR) may be a feasible alternative. We compared the efficacies and safety profiles of CE and AMR for ED-SCLC in elderly patients and chemotherapy-naive patients with poor performance status (PS).

METHODS

The records of SCLC patients who received CE or AMR as first-line chemotherapy were retrospectively reviewed and their treatment outcomes evaluated.

RESULTS

Eighty-four patients (median age 72 years; 42 each received CR and AMR) were analyzed; 34 patients had a PS score of 2. There were no significant differences in patient characteristics between the treatment groups. The median progression-free survival rates of patients in the CE and AMR groups were 5.8 and 4.8 months, respectively (P = 0.04); overall survival was 14.0 and 8.5 months, respectively (P = 0.089). Twenty-three CE group patients received AMR as second-line chemotherapy; their median overall survival from first-line chemotherapy was 18.5 months. Grade 3 or higher neutropenia occurred more frequently in patients treated with AMR (64% vs. 40%; P = 0.02), as did febrile neutropenia (14% vs. 7%).

CONCLUSIONS

CE remains a suitable first-line treatment for ED-SCLC in elderly patients or those with poor PS in comparison with AMR.

A phase I, open-label, dose-escalation study of amrubicin in combination with lenalidomide and weekly dexamethasone in previously treated adults with relapsed or refractory multiple myeloma

This phase 1 study investigated the safety of the anthracycline amrubicin combined with lenalidomide and dexamethasone in adults with relapsed or refractory multiple myeloma. A standard 3 + 3 design was used. Patients received intravenous amrubicin 40-80 mg/m² on day one, lenalidomide 15 mg orally on days 1-14, and dexamethasone 40 mg orally weekly on 21 day cycles. 14 patients were enrolled, and completed a median of three cycles. The maximum tolerated dose was not reached. One patient experienced dose limiting toxicity of dizziness and diarrhea. The most frequent non-hematologic toxicity was infection (79%). Serious adverse events included cord compression and sepsis. Three patients (21%) had a partial response or better, and seven (50%) had stable disease. The median duration of response was 4.4 months, and the median progression-free survival was 3 months. Amrubicin combined with lenalidomide and dexamethasone, was safe and demonstrated clinical activity in relapsed or refractory multiple myeloma.Clinicaltrials.gov identifier: NCT01355705.

Amrubicin and carboplatin with pegfilgrastim in patients with extensive stage small cell lung cancer: A phase II trial of the Sarah Cannon Oncology Research Consortium

PURPOSE

First-line treatment for patients with extensive-stage small cell lung cancer (SCLC) includes treatment with platinum-based combination chemotherapy. Amrubicin is a synthetic anthracycline with single-agent activity in relapsed/refractory SCLC. In an attempt to improve treatment efficacy, we evaluated amrubicin/carboplatin as first-line therapy for extensive-stage SCLC.

PATIENTS AND METHODS

In this multicenter phase II trial, patients received amrubicin (30 mg/m² daily on Days 1, 2, and 3) and carboplatin (AUC = 5 on Day 1); cycles were repeated every 21 days for 4 cycles. Pegfilgrastim (6 mg subcutaneously) was administered on Day 4 of all cycles. Overall survival (OS) proportion at 1 year was the primary endpoint. The target 1-year OS rate was 47%, an improvement of 35% from historical results with carboplatin/etoposide.

RESULTS

Eighty patients received study treatment, and 62% completed the planned 4 courses. The overall response rate was 74% (13% complete responses). The 1-year survival rate was 38% (95% CI: 25, 50). The median survival was 10 months. Myelosuppression was severe but manageable.

CONCLUSIONS

The combination of amrubicin/carboplatin was an active first-line treatment for extensive stage SCLC, but showed no indication of increased efficacy compared to standard treatments. Severe myelosuppression was common with this regimen, in spite of prophylactic pegfilgrastim. These results are consistent with those of other trials in showing no role for amrubicin in the first-line treatment of SCLC.

Phase I Study of Amrubicin and Cyclophosphamide in Patients With Advanced Solid Organ Malignancies: HOG LUN 07-130

OBJECTIVES

Relapsed small cell lung cancer (SCLC) has limited treatment options. Anthracyclines and cyclophosphamide have shown synergy in many tumors. Amrubicin (AMR) and cyclophosphamide both have single-agent activity in SCLC. This phase I trial evaluated the combination of AMR and cyclophosphamide in refractory solid organ malignancies and in relapsed SCLC.

MATERIALS AND METHODS

The primary endpoint was to determine maximum-tolerated dose and dose-limiting toxicities of the combination. Eligible patients were enrolled in sequential dose escalation cohorts in a standard 3+3 design. Treatment consisted of cyclophosphamide IV at 500 mg/m on day 1 with escalating doses of AMR IV on days 1 to 3 (25 to 40 mg/m with increments of 5 mg/m per cohort). Cycles were repeated every 21 days. Exploratory objectives analyzed the presence of NQO1 polymorphisms and topoisomerase IIA amplification and correlation with response.

RESULTS

Thirty-six patients were enrolled, of whom 18 patients had SCLC (50%). Maximum-tolerated dose was determined to be dose level 2 (cyclophosphamide 500 mg/m, AMR 30 mg/m) due to grade 4 thrombocytopenia. The main grade 3 to 4 toxicities were hematologic. Efficacy results are available for 34 patients. Partial responses, stable disease, and progressive disease rates in the overall study population were 20.6% (n=7), 38.2% (n=13), and 41.2% (n=14), respectively. Partial response, stable disease, and progressive disease rates in the SCLC patients and 1 patient with extrathoracic small cell were 36.8% (n=7), 26.3% (n=5), and 36.8% (n=7), respectively. There was no correlation between topoisomerase IIA amplification or NQO1 polymorphisms and response.

CONCLUSIONS

AMR and cyclophosphamide can be safely combined with little activity observed in heavily pretreated SCLC patients.

Phase II study of Amrubicin monotherapy in elderly or poor-risk patients with extensive disease of small cell lung cancer

Background Previous study indicated that an optional anti-cancer drug for the treatment of small-cell lung cancer (SCLC) is amrubicin. However, no prospective studies have evaluated amrubicin in chemo-naive elderly or poor-risk patients with SCLC. Therefore, this study aimed to evaluate the efficacy of amrubicin as first-line chemotherapy for elderly or poor-risk patients with extensive-disease SCLC (ES-SCLC). Methods Patients with chemotherapy-naive ES-SCLC received multiple cycles of 40 mg/m² amrubicin for 3 consecutive days every 21 days. The primary endpoint was the overall response rate (ORR), and the secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety. Results Between March 2011 and August 2015, 36 patients were enrolled in this study. Each patient received a median of four treatment cycles (range, 1-6 cycles). ORR was 52.8% [95% confidence interval (CI), 37-69%]. The median PFS and OS periods were 5.0 months (95% CI, 3.4-6.6 months) and 9.4 months (95% CI, 5.2-13.6 months), respectively. Neutropenia was the most common grade 3 or 4 adverse event (69.4%), with febrile neutropenia developing in 13.9% of patients. No treatment-related death occurred. At the time of starting second-line chemotherapy, 19 of 22 patients (86%) had significantly improved or maintained their performance status (PS) relative to their PS at the time of starting amrubicin monotherapy as first-line chemotherapy (P = 0.027). Conclusions The results of the present study suggest that amrubicin could be considered as a viable treatment option for chemotherapy-naive elderly or poor-risk patients with ES-SCLC (Clinical trial registration number: UMIN000011055 www.clinicaltrials.gov ).

The role of anthracyclines in small cell lung cancer

Small cell lung cancer (SCLC) represents the 15% of the totally of lung cancer. The percentage of cases in women is arising due to the differences in smoking patterns; it occurs almost exclusively in smokers and appears to be most common in heavy smokers. The stage of disease at presentation is the most important prognostic factor in patients with SCLC; for patients with extended stage disease, the median survival is around 10 months, and the five-year survival rate is 1 to 2 percent. The standard regimen for patients with extensive disease is cisplatin based chemotherapy. Second line chemotherapy is generally less effective than the initial treatment but it can provide significant palliation for many patients. We make a review here of the different options of second line chemotherapy and the role of anthracyclines in it.

Phase III Study Comparing Amrubicin Plus Cisplatin With Irinotecan Plus Cisplatin in the Treatment of Extensive-Disease Small-Cell Lung Cancer: JCOG 0509

Purpose

This randomized phase III trial was conducted to confirm noninferiority of amrubicin plus cisplatin (AP) compared with irinotecan plus cisplatin (IP) in terms of overall survival (OS) in chemotherapy-naive patients with extensive-disease (ED) small-cell lung cancer (SCLC).

Patients and Methods

Chemotherapy-naive patients with ED-SCLC were randomly assigned to receive IP, composed of irinotecan 60 mg/m2 on days 1, 8, and 15 and cisplatin 60 mg/m2 on day 1 every 4 weeks, or AP, composed of amrubicin 40 mg/m2 on days 1, 2, and 3 and cisplatin 60 mg/m2 on day 1 every 3 weeks.

Results

A total of 284 patients were randomly assigned to IP (n = 142) and AP (n = 142) arms. The point estimate of OS hazard ratio (HR) for AP to IP in the second interim analysis exceeded the noninferior margin (HR, 1.31), resulting in early publication because of futility. In updated analysis, median survival time was 17.7 (IP) versus 15.0 months (AP; HR, 1.43; 95% CI, 1.10 to 1.85), median progression-free survival was 5.6 (IP) versus 5.1 months (AP; HR, 1.42; 95% CI, 1.16 to 1.73), and response rate was 72.3% (IP) versus 77.9% (AP; P = .33). Adverse events observed in IP and AP arms were grade 4 neutropenia (22.5% v 79.3%), grade 3 to 4 febrile neutropenia (10.6% v 32.1%), and grade 3 to 4 diarrhea (7.7% v 1.4%).

Conclusion

AP proved inferior to IP in this trial, perhaps because the efficacy of amrubicin as a salvage therapy was differentially beneficial to IP. IP remains the standard treatment for extensive-stage SCLC in Japan.

Amrubicin: potential in combination with cisplatin or carboplatin to treat small-cell lung cancer

Small-cell lung cancer (SCLC) is the most aggressive form of lung cancer characterized by early metastasis and high mortality. In recent years, monotherapy and combination therapy of amrubicin with cisplatin or carboplatin has been actively studied and shown promise for the treatment of extensive disease SCLC (ED-SCLC). In this article, we summarize clinical trials of both monotherapy and combination therapy with amrubicin conducted in Japan, the USA, and the European Union. The results suggest that the clinical outcome of amrubicin therapy may be associated with genetic variations in patients. Further study of combination regimens in patients of different ethnicities is warranted.

Dose escalation and feasibility study of amrubicin combined with cisplatin in previously untreated patients with advanced non-small cell lung cancer

OBJECTIVES

Cisplatin is a key drug used in the treatment of non-small cell lung cancer (NSCLC), and amrubicin is one of the new active agents for NSCLC. The objective of this study was to determine the recommended dose (RD) of amrubicin in combination with a fixed dose of cisplatin, and to assess the toxicity profile and feasibility of this regimen.

METHODS

We conducted a dose escalation study of amrubicin and cisplatin in previously untreated patients with stage IIIB or IV NSCLC. Dose level 1 of amrubicin was 30 mg/m on days 1 to 3 and level 2 was 35 mg/m. Cisplatin was administered at a fixed dose of 80 mg/m on day 1. Chemotherapy was given in a 3-week cycle.

RESULTS

Twenty patients were enrolled. Dose-limiting toxicities were neutropenia, febrile neutropenia, thrombocytopenia, and creatinine elevation. Level 1 (30 mg/m) was determined to be the RD, and 35 mg/m exceeded the RD. In 17 patients treated with the RD, the overall response rate was 41.2% (95% confidence interval, 17.7-64.7) and the median survival time was 16.4 months (95% confidence interval, 13.1-19.5).

CONCLUSIONS

This amrubicin and cisplatin regimen may be feasible and promising against advanced NSCLC. The efficacy and safety of this regimen should be confirmed in a phase II study.

A phase I study of amrubicin and fixed dose of irinotecan (CPT-11) in relapsed small cell lung cancer: Japan multinational trial organization LC0303

PURPOSE

To determine the maximum tolerated dose of amrubicin (AMR) with a fixed dose of irinotecan (CPT-11).

METHODS

Patients having pathologically proven small cell lung cancer (SCLC) relapsed after one or two chemotherapies, and Eastern Cooperative Oncology Group performance status of 0 to 2 were eligible for the study. CPT-11 was delivered as 50 mg/m2 on days 1 and 8, every 21 days. AMR was delivered on day 1. Doses of AMR were level 1: 80 mg/m2, level 2: 90 mg/m2, and level 3: 100 mg/m2. Dose elevation was determined using the modified continuous reassessment method. Tolerability was assessed after the first cycle. Another two cycles were conducted when disease progression or unacceptable toxicities were not observed.

RESULTS

Eighteen patients (mean age: 66.3 years) were enrolled. A total of 40 courses were conducted. Grade 3/4 toxicities of the first cycle were leukocytopenia: 11 (61%, grade 3/4: 8/3); neutropenia: 15 (83%, grade 3/4: 6/9); and thrombocytopenia: three (17%, grade 3/4: 2/1). Other grade 3 toxicities observed were febrile neutropenia, one; infection, three; diarrhea, one; and dyspnea, one. Dose-limiting toxicity was observed in two of six patients at level 2 (neutropenia and febrile neutropenia) and in one of six at level 3 (thrombocytopenia and infection). The maximum tolerated dose was level 3, and so, the recommended dose for phase II trials was judged to be 90 mg/m2. Objective response was obtained in four of eight patients who were able to evaluate responses. Median survival time was 13 months, with 68% at 1-year survival rate.

CONCLUSIONS

This combination was well tolerated and showed encouraging activities in SCLC. Randomized phase II trials are being planned in chemonaive SCLC.

Phase I/II study of amrubicin in combination with S-1 as second-line chemotherapy for non-small-cell lung cancer without EGFR mutation

INTRODUCTION

Both amrubicin (Am) and S-1 are effective against non-small-cell lung cancer (NSCLC), and preclinical studies have demonstrated that the effect of tegafur/uracil, the original compound of S-1, in combination with Am significantly inhibits tumor growth.

METHODS

We conducted a phase I/II study of Am and S-1 against pretreated NSCLC without EGFR mutation. We fixed the dose of S-1 at 40 mg/m(2) on days 1-14 and escalated the Am dose in increments of 5 mg/m(2) from a starting dose of 30 mg/m(2)/day on days 1-3 and repeated the cycle every 4 weeks.

RESULTS

Twenty-six patients were registered. In phase I, at an Am dose of 35 mg/m(2)/day, three patients experienced grade 2 leukopenia during S-1 administration, and S-1 was withdrawn. Another patient developed grade 2 serum bilirubin in the first cycle. DLTs were observed in four of six patients at this dose level, and therefore, 30 mg/m(2)/day was set as the recommended dose for Am. Twenty patients received this recommended Am dose. Febrile neutropenia was observed in two patients, and one patient developed a grade 4 increase in serum creatinine. Grade 3 vomiting, infection, hypotension, and urinary retention were observed in one patient each, respectively. Other toxicities were mild, and there were no treatment-related deaths. Two patients showed a CR, three showed a PR, and the overall response rate was 25.0%. The median progression-free and the median survival times were 3.8 and 15.6 months, respectively, and the 1-year survival rate was 60%.

CONCLUSION

Am and S-1 every 4 weeks is an effective combination for pretreated NSCLC without EGFR mutation.

C609T polymorphism of NAD(P)H quinone oxidoreductase 1 as a predictive biomarker for response to amrubicin

INTRODUCTION

Amrubicin is a promising agent in the treatment of lung cancer, but predictive biomarkers have not yet been described. NAD(P)H:quinone oxidoreductase 1 (NQO1) is an enzyme known to metabolize amrubicinol, the active metabolite of amrubicin, to an inactive compound. We examined the relationship between NQO1 and amrubicinol cytotoxicity.

METHODS

Gene and protein expression of NQO1, amrubicinol cytotoxicity, and C609T single-nucleotide polymorphism of NQO1 were evaluated in 29 lung cancer cell lines: 14 small cell lung cancer (SCLC) and 15 non-SCLC (NSCLC). The involvement of NQO1 in amrubicinol cytotoxicity was evaluated by small interfering RNA against NQO1.

RESULTS

A significant inverse relationship between both gene and protein expression of NQO1 and amrubicinol cytotoxicity was found in all cell lines. Treatment with NQO1 small interfering RNA increased amrubicinol cytotoxicity and decreased NQO1 expression in both NSCLC and SCLC cells. Furthermore, cell lines genotyped homozygous for the 609T allele showed significantly lower NQO1 protein expression and higher sensitivity for amrubicinol than those with the other genotypes in both NSCLC and SCLC cells.

CONCLUSIONS

NQO1 expression is one of the major determinants for amrubicinol cytotoxicity, and C609T single-nucleotide polymorphism of NQO1 could be a predictive biomarker for response to amrubicin treatment.

Randomised phase II study of amrubicin as single agent or in combination with cisplatin versus cisplatin etoposide as first-line treatment in patients with extensive stage small cell lung cancer - EORTC 08062

PURPOSE

The EORTC 08062 phase II randomised trial investigated the activity and safety of single agent amrubicin, cisplatin combined with amrubicin, and cisplatin combined with etoposide as first line treatment in extensive disease (ED) small cell lung cancer (SCLC).

PATIENTS AND METHODS

Eligible patients with previously untreated ED-SCLC, WHO performance status (PS) 0-2 and measurable disease were randomised to 3 weekly cycles of either amrubicin alone 45mg/m(2) i.v. day(d) 1-3 (A), cisplatin 60mg/m(2) i.v. d1 and amrubicin 40mg/m(2) i.v. d1-3 (PA), or cisplatin 75mg/m(2) i.v. d1 and etoposide 100mg/m(2) d1, d2-3 i.v./po (PE). The primary end-point was overall response rate (ORR) as assessed by local investigators (RECIST1.0 criteria). Secondary end-points were treatment toxicity, progression-free survival and overall survival.

RESULTS

The number of randomised/eligible patients who started treatment was 33/28 in A, 33/30 in PA and 33/30 in PE, respectively. Grade (G) ⩾3 haematological toxicity in A, PA and PE was neutropenia (73%, 73%, 69%); thrombocytopenia (17%, 15%, 9.4%), anaemia (10%, 15%, 3.1%) and febrile neutropenia (13%, 18%, 6%). Early deaths, including treatment related, occurred in 1, 3 and 3 patients in A, PA and PE arms, respectively. Cardiac toxicity did not differ among the 3 arms. Out of 88 eligible patients who started treatment, ORR was 61%, (90% 1-sided confidence intervals [CI] 47-100%), 77% (CI 64-100%) and 63%, (CI 50-100%) for A, PA and PE respectively.

CONCLUSION

All regimens were active and PA met the criteria for further investigation, despite slightly higher haematological toxicity.

Review of the management of relapsed small-cell lung cancer with amrubicin hydrochloride

Lung cancer is the leading cause of cancer death, and approximately 15% of all lung cancer patients have small-cell lung cancer (SCLC). Although second-line chemotherapy can produce tumor regression, the prognosis is poor. Amrubicin hydrochloride (AMR) is a synthetic anthracycline anticancer agent and a potent topoisomerase II inhibitor. Here, we discuss the features of SCLC, the chemistry, pharmacokinetics, and pharmacodynamics of AMR, the results of in vitro and in vivo studies, and the efficacy and safety of AMR monotherapy and combination therapy in clinical trials. With its predictable and manageable toxicities, AMR is one of the most attractive agents for the treatment of chemotherapy-sensitive and -refractory relapsed SCLC. Numerous studies are ongoing to define the applicability of AMR therapy for patients with SCLC. These clinical trials, including phase III studies, will clarify the status of AMR in the treatment of SCLC.

Phase II trial of amrubicin and carboplatin in patients with sensitive or refractory relapsed small-cell lung cancer

Amrubicin is a novel, totally synthesized anthracycline derivative, and has antitumor activity against several human tumor xenografts. The combination of amrubicin with platinum derivative showed additive effect against a human small-cell lung cancer (SCLC) cell line. Until now, the combination of amrubicin plus carboplatin has not been studied in patients with previously treated SCLC. Therefore, we examined the safety and efficacy of the combination of amrubicin plus carboplatin in patients with sensitive or refractory relapsed SCLC. Patients with previously treated SCLC were eligible if they had a performance status of 2 or less, were 75 years or younger, and had adequate organ function. Twenty-five patients were enrolled (21 men and 4 women; median age, 65 years; age range 55-73 years). Patients received the combination of amrubicin (30 mg/m(2) on days 1-3) plus carboplatin (with a target area under the concentration-versus-time curve of 4 mg min/ml using the Calvert formula on day 1) every 3 weeks. The overall response rate was 36.0% (95% confidence interval [CI], 18.0-57.5%). Response rates differed significantly between patients with sensitive relapse (58.3%; 95% CI, 27.7-84.8%) and those with refractory relapse (15.4%; 95% CI, 1.9-15.4%; p=0.03). The median survival time (MST) from the start of this treatment was 7 months (range: 1-42 months); the MST of patients with sensitive relapse (10 months) was significantly longer than that of patients with refractory relapse (5 months: p=0.004). The median progression-free survival (PFS) time was 3 months (range: 1-14 months): the median PFS time of patients with sensitive relapse (5 months) was significantly longer than that of patients with refractory relapse (2 months; p=0.01). The most frequent grade 3-4 toxicity was myelosuppression, especially neutropenia, which developed in 88% of patients. Grade 3-4 thrombocytopenia developed in 44% of patients, and anemia developed in 56%. Nonhematologic toxicities were generally mild to moderately severe and temporary. None of the patients had cardiotoxicity. In conclusion, this therapy is effective and well tolerated for previously treated SCLC.

Over-expression of MDR1 in amrubicinol-resistant lung cancer cells

PURPOSE

Amrubicin, a totally synthetic 9-aminoanthracycline anticancer drug, has shown promising activity for lung cancer, but little is known about the mechanism of resistance for this agent. This study was aimed to clarify the role of P-glycoprotein (P-gp) in amrubicinol, an active metabolite of amrubicin, resistance in lung cancer cells.

METHODS

Amrubicinol-resistant cell line PC-6/AMR-OH was developed by continuously exposing the small-cell lung cancer cell line PC-6 to amrubicinol. Gene expression level of MDR1, which encodes P-gp, and intracellular accumulation of amrubicinol were evaluated by PC-6 and PC-6/AMR-OH cells. The involvement of MDR1 in amrubicinol resistance was evaluated by treatment with P-gp inhibitor verapamil and small interfering RNA (siRNA) against MDR1. Also, expression levels and single-nucleotide polymorphisms (SNPs) of MDR1 in 22 lung cancer cell lines were examined, and the relationships between these factors and sensitivity to amrubicinol were evaluated.

RESULTS

The MDR1 gene was increased approximately 4,500-fold in PC-6/AMR-OH cells compared with PC-6 cells, and intracellular accumulation of amrubicinol in PC-6/AMR-OH cells was decreased to about 15 percent of that in PC-6 cells. Treatment with verapamil and siRNA against MDR1 significantly increased the sensitivity to amrubicinol in PC-6/AMR-OH cells with increased cellular accumulation of amrubicinol. Meanwhile, neither MDR1 gene expression levels nor SNPs of the gene were associated with amrubicinol sensitivity.

CONCLUSIONS

Results of this study indicate that increased MDR1 expression and P-gp activity confer acquired resistance to amrubicinol. In contrast, neither expression level nor SNPs of MDR1 are likely to be predictive markers for amrubicin activity.

Efficacy and safety of amrubicin hydrochloride for treatment of relapsed small cell lung cancer

Long-term survival is quite uncommon in refractory small cell lung cancer (SCLC) patients, with less than 25% of patients with limited-stage disease and 1%-2% of patients with extensive-stage disease remaining alive at five years. Recent clinical studies have demonstrated the promising efficacy of amrubicin for patients with relapsed SCLC. This review presents the results of clinical studies showing the efficacy and safety of amrubicin for the treatment of relapsed SCLC. Amrubicin is a synthetic anthracycline agent with a similar structure to doxorubicin, in which the hydroxyl group at position 9 in amrubicin is replaced by an amino group to enhance efficacy. It is converted to an active metabolite, amrubicinol, which is 5-54 times more active than amrubicin. Amrubicin and amrubicinol are inhibitors of DNA topoisomerase II, exerting their cytotoxic effects by stabilizing a topoisomerase II-mediated cleavable complex. The toxicity of amrubicin is similar to that of doxorubicin, although amrubicin shows almost no cardiotoxicity. In the relevant trials, amrubicin was administered intravenously at a dose of 35-40 mg/m(2) on days 1-3 every three weeks. The response rate was 34%-52% and median survival times were 8.1-12.0 months. Common hematologic toxicities included neutropenia, leucopenia, anemia, thrombocytopenia, and febrile neutropenia. Nonhematologic adverse events included Grade 3-4 anorexia, asthenia, hyponatremia, and nausea. The results of the studies which demonstrated the efficacy of monotherapy for relapsed SCLC involved mainly Japanese patients. Therefore, it is necessary to conduct more clinical studies in non-Japanese patients to confirm the efficacy of amrubicin.

Recent Pharmacological Advances: Focus on Small-cell Lung Cancer

Small cell lung cancer (SCLC) represents approximately 15% of all lung cancers, and is the most aggressive form of lung cancer. Left untreated, the time from diagnosis to death is 2–3 months. With current treatment, expected survival is 7–20 months, depending on the stage of disease. A new drug, amrubicin, is approved in Japan for lung cancer and has demonstrated efficacy in U.S. and European phase II trials of SCLC patients with either untreated disease or relapsed refractory illness. In a phase II study of amrubicin in previously untreated patients, response rates reached 75% with a median survival time of almost 1 year. Amrubicin is a fully synthetic 9-aminoanthracycline, and an analog of doxorubicin and epirubicin. The major mechanism of action of amrubicin is inhibition of topoisomerase II. Unlike doxorubicin, however, it exhibits little or no cardiotoxicity in clinical studies and preclinical models. In preclinical rodent tumor models, it is selectively distributed to tumour tissue and is not detected in the heart when compared with doxorubicin, which is distributed equivalently to these sites. The primary metabolite of amrubicin, amrubicinol, is up to 100 times more cytotoxic in vitro than the parent compound. This review describes the mechanisms of action of amrubicin as well as clinical studies which demonstrate the potential of this drug in future SCLC treatment. The review also puts forward hypothetical considerations for the use of other drugs such as lenalidomide, an immunomodulatory drug acting on multiple signalling pathways, or histone deacetylase inhibitors, in combination with amrubicin in SCLC.

Amrubicin for the treatment of advanced lung cancer

Although the advancement of the chemotherapy of non-small cell lung cancer and small cell lung cancer is remarkable in recent years, it is still unsatisfactory. Therefore, some new agents or a new treatment strategy for lung cancer is required. Amrubicin is a totally synthetic anthracycline anticancer drug that acts as a potent topoisomerase II inhibitor. Recently, amrubicin has been approved in Japan for the treatment of small- and non-small cell lung cancers and some clinical trials about amrubicin were conducted in Japan, and promising results have been reported for the treatment of small cell lung cancer in particular. The preclinical, pharmacology and clinical data of amrubicin for the treatment of advanced lung cancer are reviewed.

Amrubicin for treating elderly and poor-risk patients with small-cell lung cancer

BACKGROUND

This study was conducted to evaluate the efficacy of amrubicin as first-line chemotherapy for elderly and poor-risk patients with extensive-disease small-cell lung cancer (ED-SCLC).

METHODS

Untreated SCLC patients who were >75 years of age or had a performance status of 2 or more were eligible. Amrubicin (35 or 40 mg/m(2) on days 1-3 every 3 weeks) was administered.

RESULTS

Between January 2003 and May 2009, 27 patients were evaluated. The median number of treatment cycles was 4 (1-6). Grade 3 or 4 hematologic toxicities comprised neutropenia (63%), leukopenia (56%), thrombocytopenia (15%), and anemia (19%). Febrile neutropenia was observed in four (15%) patients. No treatment-related deaths occurred. The nonhematologic toxicities were mild. The overall response rate was 70%. Progression-free survival, median survival time, and the 1-year survival rate were 6.6 months, 9.3 months, and 30%, respectively. The 40 mg/m(2) dose was feasible and had a tendency to be more effective than the 35 mg/m(2) dose.

CONCLUSIONS

Amrubicin exhibits activity and acceptable toxicities for elderly and poor-risk patients with ED-SCLC in the first-line treatment setting.

Next-generation anthracycline for the management of small cell lung cancer: focus on amrubicin

Amrubicin is a totally synthetic anthracycline anticancer agent that acts as a potent topoisomerase II inhibitor. Amrubicin has been approved in Japan for the treatment of lung cancer, and the results from clinical studies of amrubicin as a single agent or as part of combination regimens for lung cancer, particularly for small cell lung cancer, conducted in Japan and overseas have been promising. Amrubicin should be included among new treatment strategies especially for chemoresistant patients. Here, preclinical, pharmacological, and clinical data on the use of amrubicin for the treatment of small cell lung cancer are reviewed.

A case of intimal sarcoma of the pulmonary artery treated with chemoradiotherapy

We report on a 45-year-old woman with intimal sarcoma of the pulmonary artery. She presented with a chief complaint of shortness of breath. Computed tomography (CT) of the chest showed an intraluminal hypoattenuated area extending from the main pulmonary artery into the right main pulmonary artery and bilateral lobar pulmonary arteries. She underwent resection of the lobulated mass from the pulmonary artery. The tumor was diagnosed as an intimal sarcoma. Although she received chemotherapy with amrubicin and carboplatin when the tumor recurred, the tumor enlarged. After radiotherapy was performed, CT of the chest showed shrinkage of the tumor and the regression of consolidation and ground-glass opacity. Radiotherapy and chemotherapy are treatment option for patients with pulmonary artery sarcoma.

Dose escalation study of amrubicin in combination with fixed-dose irinotecan in patients with extensive small-cell lung cancer

BACKGROUND

The combination of amrubicin (Am) and irinotecan (CPT) shows appreciable activity against small-cell lung cancer (SCLC) in vitro.

PATIENTS AND METHODS

We conducted a dose escalation study of Am in combination with CPT to determine the qualitative and quantitative toxicities and efficacy against extensive (ED) SCLC.

RESULTS

Thirteen previously untreated patients with ED-SCLC were treated with CPT at 60 mg/m(2) on day 1 and dose-escalated Am on days 1-3 with prophylactic granulocyte colony-stimulating factor subcutaneously on days 5-9 every 2-3 weeks. At level 3 (40 mg/m(2)/day Am), 3 of 4 registered patients experienced dose-limiting toxicity such as grade 4 neutropenic fever, and therefore, this was defined as the maximum tolerated dose. A total of 31 courses was administered at dose level 2 (35 mg/m(2)/day) in 6 patients, and grade 4 neutropenia was observed during 5 courses (16.1%). Non-hematological toxicities, except 1 course of grade 3 transfusion of red blood cells and 1 course of grade 3 transaminase elevation, were mild. Thus, dose level 2 of Am was recommended for further study. One patient achieved complete remission and 12 achieved partial remission, and the overall response rate was 100%. The median survival time was 17.4 months, and the 1-year survival rate was 76.9%.

CONCLUSIONS

CPT at 60 mg/m(2) on day 1 and Am at 35 mg/m(2)/day on days 1-3 with granulocyte colony-stimulating factor support every 3 weeks is recommended for Japanese patients with ED-SCLC.

Small cell lung cancer

Small cell lung cancer accounts for approximately 15% of bronchogenic carcinomas. It is the cancer most commonly associated with various paraneoplastic syndromes, including the syndrome of inappropriate antidiuretic hormone secretion, paraneoplastic cerebellar degeneration, and Lambert-Eaton myasthenic syndrome. Because of the high propensity of small cell lung cancer to metastasize early, surgery has a limited role as primary therapy. Although the disease is highly sensitive to chemotherapy and radiation, cure is difficult to achieve. The combination of platinum and etoposide is the accepted standard chemotherapeutic regimen. It is also the accepted standard therapy in combination with thoracic radiotherapy (TRT) for limited-stage disease. Adding TRT increases absolute survival by approximately 5% over chemotherapy alone. Thoracic radiotherapy administered concurrently with chemotherapy is more efficacious than sequential therapy. Furthermore, the survival benefit is greater if TRT is given early rather than late in the course of chemotherapy. Regardless of disease stage, no relevant survival benefit results from increased chemotherapy dose intensity or dose density, altered mode of administration (eg, alternating or sequential administration) of various chemotherapeutic agents, or maintenance chemotherapy. Prophylactic cranial radiation prevents central nervous system recurrence and can improve survival. In Japan and some other Asian countries, the combination of irinotecan and cisplatin is the standard chemotherapeutic regimen. Clinical trials using thalidomide, gefitinib, imatinib, temsirolimus, and farnesyltransferase inhibitors have not shown clinical benefit. Other novel agents such as bevacizumab have shown promising early results and are being evaluated in larger trials.

Evaluation of the Recommended Dose and Efficacy of Amrubicin as Second- and Third-Line Chemotherapy for Small Cell Lung Cancer

INTRODUCTION

This study was conducted to evaluate the recommended dose and activity of amrubicin (AMR) as second- or third-line chemotherapy for small-cell lung cancer (SCLC).

METHODS

Small-cell lung cancer patients with measurable disease who had previously been treated with at least one platinum-based chemotherapy regimen and had an Eastern Cooperative Oncology Group performance status of 0-2 were eligible. Two groups of patients were selected: (1) a group to be treated with second-line chemotherapy and (2) a group to be treated with third-line chemotherapy. AMR was administered to both groups as a 5-minute daily intravenous injection at a dose of 40 or 35 mg/m2 for three consecutive days every 3 weeks.

RESULTS

Between March 2003 and June 2006, 27 patients (second-line, 40 mg/m2: 13 patients; third-line, 40 mg/m2: seven patients; and 35 mg/m2: seven patients) were enrolled. Although the 40-mg/m2 dose of AMR was feasible (one of 13 patients developed febrile neutropenia and four of 13 patients had grade 4 neutropenia) and effective (six of 13 patients had a partial response) in the second-line group, it produced unacceptable toxicity in a third-line setting (three of seven patients with grade 3 nonhematologic toxicities [febrile neutropenia in two patients and fatigue in one patient] and four of seven patients with grade 4 neutropenia). The 35-mg/m2 dose of AMR had acceptable toxicity in the third-line group (one of seven patients with febrile neutropenia and one of seven had grade 4 neutropenia) and moderate efficacy (one of seven patients had a partial response and two of seven had stable disease).

CONCLUSIONS

AMR exhibits significant activity as second-line or third-line chemotherapy for small-cell lung cancer. The recommended dose is 40 mg/m2 in a second-line setting and 35 mg/m2 in a third-line setting.

Amrubicin for non-small-cell lung cancer and small-cell lung cancer

Amrubicin is a totally synthetic anthracycline anticancer drug and a potent topoisomerase II inhibitor. Recently, amrubicin was approved in Japan for the treatment of small- and non-small-cell lung cancers (SCLC and NSCLC). Here, we review the efficacy and toxicities of amrubicin monotherapy and amrubicin in combination with cisplatin for extensive-disease SCLC (ED-SCLC), and of amrubicin monotherapy for advanced NSCLC, as observed in the clinical trials. Recommended dosage for previously untreated advanced NCSLC was 45 mg/m2/day by intravenous administration for 3 days. Dose-limiting toxicities were leucopenia, thrombocytopenia, and gastrointestinal disturbance. Response rate was 27.9% for advanced NSCLC, and 75.8% for ED-SCLC with a median survival time (MST) of 11.7 months. Recommended dosage of amrubicin was 40 mg/m2/day in combination with cisplatin at 60 mg/m2/day, with MST of 13.6 months and 1-year survival rate of 56.1%. In sensitive or refractory relapsed SCLC, response rate was 52 and 50%, progression-free survival was 4.2 and 2.6 months, overall survival was 11.6 and 10.3 months, and 1-year survival rate was 46 and 40%, respectively. These results are promising for the treatment of both NSCLC and SCLC. Further clinical trials will clarify the status of amrubicin in the treatment of lung cancer.

Phase II study of amrubicin, 9-amino-anthracycline, in patients with advanced non-small-cell lung cancer: a West Japan Thoracic Oncology Group (WJTOG) study

PURPOSE

We conducted a multicenter phase II study of amrubicin, a novel 9-aminoanthracycline, to evaluate its efficacy and safety in patients with non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Entry requirements included cytologically or histologically proven measurable NSCLC, stage III or IV, no prior therapy, an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2, and adequate organ function. Amrubicin was given by daily intravenous injection at 45 mg/m2/day for three consecutive days, repeated at 3 week intervals. Each patient received at least three treatment cycles.

RESULTS

Sixty-two patients were enrolled in this study. Of the 62 registered patients, 60 were eligible and assessable for efficacy, and 59 for toxicity. Overall response rate was 18.3% (95% confidence interval [CI], 9.5 to 30.4%) and median survival time was 8.2 months (95% CI, 6.7 to 10.4 months). Major toxicity was myelosuppression, with incidences of grade 3 or 4 toxicity of 78.0% for neutropenia, 54.2% for leukopenia, 30.5% for anemia, and 28.8% for thrombocytopenia. Non-hematological toxicities with a greater than 50% incidence were anorexia (69.5%), nausea/vomiting (55.9%), and alopecia (75.9%), but were relatively mild, with grade 3 toxicities observed in only one patient each (1.7%).

CONCLUSION

Amrubicin was an active, well-tolerated agent in the treatment of NSCLC.

Treatment options for relapsed small-cell lung cancer

Small-cell lung cancer is a chemo-sensitive disease with a response rate ranging from 70 to 90% for first-line treatment; however, relapses are very common and as a result long-term survival is poor. Chemotherapy has demonstrated a benefit over the best supportive care, even in patients who have relapsed after initial treatment with a platinum-based regimen. Agents currently being used in salvage therapy include topotecan, cyclophosphamide, doxorubicin and vincristine regimen. In the last 5 years, several drugs have shown promise in initial evaluation; however, randomized phase III trials would be needed to answer this question. Our understanding of the biology of small-cell lung cancer has improved dramatically over the past few years and this has translated into the developments of new therapeutic targets for this disease. Agents affecting several targets, including bcl-2, matrix metalloproteinases, epidermal growth factors and angiogenesis, are being studied currently and have the potential to change the treatment paradigms of this otherwise fatal malignancy. This review focuses on the various current and future options, including cytoxic and targeted agents, for salvage therapy in patients with this disease.

Amrubicin, a novel 9-aminoanthracycline, enhances the antitumor activity of chemotherapeutic agents against human cancer cells in vitro and in vivo

Amrubicin, a completely synthetic 9-aminoanthracycline derivative, is an active agent in the treatment of untreated extensive disease-small-cell lung cancer and advanced non-small-cell lung cancer. Amrubicin administered intravenously at 25 mg/kg substantially prevented the growth of five of six human lung cancer xenografts established in athymic nude mice, confirming that amrubicin as a single agent was active in human lung tumors. To survey which antitumor agent available for clinical use produces a synergistic interaction with amrubicin, we examined the effects in combinations with amrubicinol, an active metabolite of amrubicin, of several chemotherapeutic agents in vitro using five human cancer cell lines using the combination index (CI) method of Chou and Talalay. Synergistic effects were obtained on the simultaneous use of amrubicinol with cisplatin, irinotecan, gefitinib and trastuzumab, with CI values after 3 days of exposure being <1. Additive effect was observed with the combination containing vinorelbine with CI values indistinguishable from 1, while the combination of amrubicinol with gemcitabine was antagonistic. All combinations tested in vivo were well tolerated. The combinations of cisplatin, irinotecan, vinorelbine, trastuzumab, tegafur/uracil, and to a lesser extent, gemcitabine with amrubicin caused significant growth inhibition of human tumor xenografts without pronouncedly enhancing body weight loss, compared with treatment using amrubicin alone at the maximum tolerated dose. Growth inhibition of tumors by gefitinib was not antagonized by amrubicin. These results suggest that amrubicin appears to be a possible candidate for combined use with cisplatin, irinotecan, vinorelbine, gemcitabine, tegafur/uracil or trastuzumab.

Amrubicin for the Treatment of Small Cell Lung Cancer: Does Effectiveness Cross the Pacific?

Amrubicin is a synthetic 9-aminoanthracycline that has significant antitumor activity in Japanese patients with extensive stage small cell lung cancer (SCLC). Clinical trials ongoing in the United States and Europe will determine whether amrubicin will be effective in other ethnic groups (whites) or whether this will be an example of geographic and/or genetic variation. Genetic polymorphisms in the UGT1A1 gene have been identified as one of the causes of the increased diarrhea seen in white patients treated with irinotecan when compared with Japanese patients. Nicotinamide adenine dinucleotide phosphate, reduced form-quinone oxidoreductase (NQ01) is an enzyme that participates in the metabolism of amrubicin and polymorphisms of the enzyme, known to occur in the Asian population, might explain the effectiveness of the drug in Japanese patients with small cell lung cancer. Studies to evaluate the drug in US and European patients with extensive stage small cell lung cancer are ongoing. Levels of NQ01 will also be determined in these studies.

Phase II Trial of Amrubicin for Treatment of Refractory or Relapsed Small-Cell Lung Cancer: Thoracic Oncology Research Group Study 0301

Purpose

This multicenter, phase II study was conducted to evaluate the activity of amrubicin, a topoisomerase II inhibitor, against refractory or relapsed small-cell lung cancer (SCLC).

Patients and Methods

SCLC patients with measurable disease who had been treated previously with at least one platinum-based chemotherapy regimen and had an Eastern Cooperative Oncology Group performance status of 0 to 2 were eligible. Two groups of patients were selected: patients who experienced first-line treatment failure less than 60 days from treatment discontinuation (refractory group), and patients who responded to first-line treatment and experienced disease progression ≥ 60 days after treatment discontinuation (sensitive group). Amrubicin was administered as a 5-minute daily intravenous injection at a dose of 40 mg/m2 for 3 consecutive days, every 3 weeks.

Results

Between June 2003 and December 2004, 60 patients (16 refractory and 44 sensitive) were enrolled. The median number of treatment cycles was four (range, one to eight). Grade 3 or 4 hematologic toxicities comprised neutropenia (83%), thrombocytopenia (20%), and anemia (33%). Febrile neutropenia was observed in three patients (5%). Nonhematologic toxicities were mild. No treatment-related death was observed. The overall response rates were 50% (95% CI, 25% to 75%) in the refractory group, and 52% (95% CI, 37% to 68%) in the sensitive group. The progression-free survival, overall survival, and 1-year survival in the refractory group and the sensitive group were 2.6 and 4.2 months, 10.3 and 11.6 months, and 40% and 46%, respectively.

Conclusion

Amrubicin exhibits significant activity against SCLC, with predictable and manageable toxicities; this agent deserves to be studied more extensively in additional trials.

Amrubicin induces apoptosis in human tumor cells mediated by the activation of caspase-3/7 preceding a loss of mitochondrial membrane potential

Amrubicin, a completely synthetic 9-aminoanthracycline derivative, inhibits cell growth by stabilizing a topoisomerase II-DNA complex. This study was designed to examine the apoptosis induced in human leukemia U937 cells by amrubicin and its active metabolite amrubicinol. Amrubicin, amrubicinol and other antitumor agents, such as daunorubicin and etoposide, induced typical apoptosis with characteristic nuclear morphological change and DNA fragmentation. Measuring the population of sub-G(1) phase cells, it was found that under conditions where cell growth was inhibited by either amrubicin or amrubicinol, U937 cells underwent apoptotic cell death in a dose-dependent manner accompanied by an arrest of the cell cycle at G(2)/M. Furthermore, amrubicin- and amrubicinol-induced apoptosis was mediated by the activation of caspase-3/7, but not caspase-1, preceding a loss of mitochondrial membrane potential. These results indicate that both a reduction in mitochondrial membrane potential and the activation of caspase-3/7 are key events in the apoptosis induced by amrubicin and amrubicinol as well as the other antitumor agents. In addition, studies with oligomycin suggested that the apoptosis induced by amrubicin and amrubicinol involved substantially different pathways from that triggered by daunorubicin and etoposide. Oligomycin blocked the etoposide-induced increase in the number of sub-G(1) phase cells without preventing the activation of caspase-3/7, and had no inhibitory effect on the expansion of the sub-G(1) population in daunorubicin-treated cells, whereas apoptosis-related changes caused by amrubicin and amrubicinol were suppressed in the presence of oligomycin.

Phase II study of amrubicin in previously untreated patients with extensive-disease small cell lung cancer: West Japan Thoracic Oncology Group (WJTOG) study

PURPOSE

To evaluate the efficacy and safety of amrubicin, (+)-(7S, 9S)-9-acetyl-9-amino-7-[(2-deoxy-beta-D-erythro-pentopyranosyl )oxy]-7,8,9,10-tetrahydro-6,11-dihydroxy-5,12-naphthacenedione hydrochloride, in previously untreated patients with extensive-disease small cell lung cancer (SCLC).

PATIENTS AND METHODS

A total of 35 previously untreated patients with extensive-disease SCLC were entered into the study. Amrubicin was given by daily intravenous infusion at 45 mg/m(2)/day for 3 consecutive days, every 3 weeks. Unless there was tumor regression of 25% or greater after the first cycle, or 50% or greater after the second cycle, treatment was switched to salvage chemotherapy in combination with etoposide (100 mg/m(2), days 1, 2, and 3) and cisplatin (80 mg/m(2), day 1).

RESULTS

Of the 35 patients entered, 33 were eligible and assessable for efficacy and toxicity. Of the 33 patients, 3 (9.1%) had a complete response (95% confidence interval [CI], 1.9-24.3%) and 22 had a partial response, for an overall response rate of 75.8% (95% CI, 57.7-88.9%). Median survival time was 11.7 months (95% CI, 9.9-15.3 months), and 1-year and 2-year survival rates were 48.5% and 20.2%, respectively. The most common toxicity was hematologic. Non-hematologic toxicity of grade 3 or 4 was only seen in 3 patients with anorexia (9.1%) and 1 patient with alopecia (3.0%). Salvage chemotherapy was administered to only 6 patients.

CONCLUSION

Amrubicin was active for extensive-disease SCLC with acceptable toxicity. Further studies in combination with other agents for SCLC are warranted.

Phase I and pharmacologic study of irinotecan and amrubicin in advanced non-small cell lung cancer

PURPOSE

We conducted a Phase I trial of irinotecan (CPT-11), a topoisomerase I inhibitor, combined with amrubicin, a topoisomerase II inhibitor. The aim was to determine the maximum tolerated dose (MTD) of amrubicin combined with a fixed dose of CPT-11 as well as the dose-limiting toxicities (DLT) of this combination in patients with advanced non-small cell lung cancer.

PATIENTS AND METHODS

Eleven patients with stage IIIB or IV disease were treated at 3-week intervals with amrubicin (5-min intravenous injection on days 1-3) plus 60 mg/m2 of CPT-11 (90-min intravenous infusion on days 1 and 8). The starting dose of amrubicin was 25 mg/m2, and it was escalated in 5 mg/m2 increments until the maximum tolerated dose was reached.

RESULTS

The 30 mg/m2 of amrubicin dose was one dose level above the MTD, since three of the five patients experienced DLT during the first cycle of treatment at this dose level. Diarrhea and leukopenia were the DLT, while thrombocytopenia was only a moderate problem. Amrubicin did not affect the pharmacokinetics of CPT-11, SN-38 or SN-38 glucuronide. Except for one patient, the biliary index on day-1 correlated well with the percentage decrease of neutrophils in a sigmoid Emax model. There were five partial responses among 11 patients for an overall response rate of 45%.

CONCLUSION

The combination of amrubicin and CPT-11 seems to be active against non-small cell lung cancer with acceptable toxicity. The recommended dose for Phase II studies is 60 mg/m2 of CPT-11 (days 1 and 8) and 25 mg/m2 of amrubicin (days 1-3) administered every 21 days.

Multicenter phase II study of amrubicin, 9-amino-anthracycline, in patients with advanced non-small-cell lung cancer (Study 1): West Japan Thoracic Oncology Group (WJTOG) trial

PURPOSE

Amrubicin is a novel 9-aminoanthracycline. This multicenter phase II study was conducted to evaluate the efficacy and safety of amrubicin in patients with non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Sixty-one previously untreated patients with stage III or IV NSCLC were entered this study. The patients were required to have cytologically or histologically proven measurable NSCLC, an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2, and adequate organ function. Amrubicin was administered by daily intravenous injection at 45 mg/m2/day for 3 consecutive days every 3 weeks. At least 3 cycles of treatment were administered to each patient.

RESULTS

All 61 patients registered in this trial were eligible and assessable for efficacy and toxicity. Of them, 17 patients achieved objective responses, consisting of one complete response and 16 partial responses, and the overall response rate was 27.9% (95% confidence interval [CI], 17.1% to 40.8%). The median survival time was 9.8 months (95% CI, 7.7 months to 14.9 months). The major toxicity was myelosuppression. The incidences of grade 3 or 4 toxicity were 72.1% for neutropenia, 52.5% for leukopenia, 23.0% for anemia, and 14.8% for thrombocytopenia. As noticeable toxic events, grade 3 hypotention and alkaline phosphatase elevation were transiently observed in one patient each. In addition, three patients who had had asymptomatic interstitial pneumonitis, identified by diagnostic imaging before treatment, aggravated after amrubicin treatment; two of them died. Other non-hematologic toxicities were relatively mild.

CONCLUSION

Amrubicin was an active, well-tolerated agent in the treatment of NSCLC.

Phase I study of amrubicin hydrochloride and cisplatin in patients previously treated for advanced non-small cell lung cancer

OBJECTIVE

A single-center phase I trial was designed to determine both the dose-limiting toxicities and the maximum tolerated dose (MTD) for amrubicin hydrochloride in combination therapy with cisplatin for advanced non-small cell lung cancer (NSCLC) patients with prior chemotherapy.

METHODS

Eligible patients received amrubicin and cisplatin on days 1 through 3 every 3 or 4 weeks. Cisplatin was administered at a fixed dosage of 20 mg/m(2) while the administered dose of amrubicin was started at 20 mg/m(2). Each group comprised 3 or 6 patients. When dose limiting toxicities were noted in three or more of six patients at a particular level, that level was estimated to be the MTD.

RESULTS

Fifteen patients were enrolled in this study, including 5 males and 10 females, with a median age of 57. The dose limiting toxicities included grade 4 neutropenia which lasted 4 or more days and febrile neutropenia. The non-hematologic toxicities were well managed and rarely severe. The MTD of amrubicin in this combination regimen was estimated to be 30 mg/m(2).A partial response was observed in 4 of 15 patients (27%).

CONCLUSIONS

The recommended dose was thus determined to be 25 mg/m(2) amrubicin with 20 mg/m(2) cisplatin for 3 consecutive days. A phase II study is currently underway.