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.

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.

Relapsed small cell lung cancer: treatment options and latest developments

According to recent analyses, there was a modest yet significant improvement in median survival time and 5-year survival rate of limited stage small cell lung cancer (SCLC) in North America, Europe, Japan and other countries over the last 30 years. The median survival time of limited stage SCLC is 15-20 months and 5-year survival rate is 15% or less. In terms of extensive stage SCLC, a median survival time of 9.4-12.8 months and 2-year survival of 5.2-19.5% are still disappointing. Despite being highly sensitive to first-line chemotherapy and radiotherapy treatments, most patients with SCLC experience relapse within 2 years and die from systemic metastasis. While several clinical trials of cytotoxic chemotherapies and molecular targeting agents have been investigated in the treatment of relapsed SCLC, none showed a significant clinical activity to be able to exceed topotecan as second-line chemotherapy. There are problematic issues to address for relapsed SCLC, such as standardizing the treatment for third-line chemotherapy. Topotecan alone was the first approved therapy for second-line treatment for relapsed SCLC. Amrubicin is a promising drug and a variety of trials evaluating its efficacy have been carried out. Amrubicin has shown superiority to topotecan in a Japanese population, but was not superior in a study of western patients. There are some controversial issues for relapsed SCLC, such as treatment for older patients, third-line chemotherapy and efficacy of molecular targeting therapy. This article reviews current standard treatment, recent clinical trials and other topics on relapsed SCLC.

Current and emerging pharmacotherapies for the treatment of relapsed small cell lung cancer

Small cell lung cancer (SCLC) is a very aggressive cancer with poor outcome if left untreated, but it is also one of the most chemotherapy responsive cancers. Overall it has a very poor prognosis especially if it is chemotherapy resistant to first line treatment. Second line chemotherapy has not been very beneficial in SCLC as opposed to breast cancer and lymphoma. In the last few years topotecan is the only drug that has been approved by the food and drug administration (FDA) for the second line treatment of SCLC but in Japan another drug, amrubicin is approved. There are many combinations of different chemotherapies available in moderate to high intensity, in this difficult to treat patient to overcome the chemo resistance, but many of these studies are small or phase II trials. In this article we have reviewed single agent and multidrug regimens that were studied in both chemo sensitive and refractory setting, including the most recent clinical trials.

Amrubicin for the treatment of neuroendocrine carcinoma of the gastrointestinal tract: a retrospective analysis of five cases

PURPOSE

A standard chemotherapy regimen for neuroendocrine carcinoma of the gastrointestinal tract (GI-NEC) has not been established. Treatment usually consists of platinum doublets, consistent with the standard treatment for small-cell lung cancer (SCLC), with which it shares clinicopathological similarities. Here, we retrospectively examined responses of five GI-NEC patients treated with amrubicin chloride (AMR) which has shown activity against SCLC as salvage therapy.

METHODS

Five patients with histologically proven unresectable GI-NEC in whom previous chemotherapy regimens had failed were treated with AMR, a synthetic anthracycline with potent topoisomerase II inhibition.

RESULTS

Primary tumors were located in the esophagus in three patients, anus in one, and colon in one. AMR was administered intravenously at 35-40 mg/m(2) on days 1-3 every 3 weeks for a median of six treatment cycles (range, 2-8). Although all patients had received one to four previous chemotherapy regimens, including cisplatin doublets, three of five achieved objective responses to AMR. All three had esophageal NEC in relapse following combination treatment with irinotecan plus cisplatin. The most common adverse events of ≥ grade 3 were neutropenia (75%), anemia (60%), thrombocytopenia (20%), and febrile neutropenia (20%).

CONCLUSIONS

Single-agent AMR achieved objective responses in three of five patients with GI-NEC. This compound may be a candidate for prospective evaluation in a larger series.

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 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.

Retrospective analysis of Japanese patients with relapse or refractory small-cell lung cancer treated with amrubicin hydrochloride

Amrubicin (AMR) is one of the most active chemotherapeutic agents for small-cell lung cancer (SCLC). Previous phase II studies reported on its effectiveness and severe hematological toxicities. However, AMR has yet to be approved outside Japan. Subsequently, no extensive evidence of its effects exist. Between January 2004 and October 2009, 69 patients received AMR for relapsed SCLC at our hospital. We reviewed these patients, and analyzed the efficacy and hematological toxicities of AMR. There were 27 sensitive relapses (S) and 42 refractory relapses (R). Patients received platinum agents, and 43 and 71% of the patients received etoposide and irinotecan, respectively. The median number of treatment cycles was 3 (range 1-14), and the response rate was 51% (70% in the S and 38% in the R cases, respectively). In patients administered with AMR as second-line therapy, the response rate was 55% and as third-line therapy, 39%. Median progression-free survival time was 3.2 months in the S and 1.9 months in the R patients (p=0.1071). Median survival time from the start of AMR was 6.2 months in the S and 4.8 months in the R cases (p=0.0045). The frequency of grade ≥3 hematological toxicities was leukopenia (41%), neutropenia (51%), anemia (14%), thrombocytopenia (17%) and febrile neutropenia (12%). No treatment-related death was observed. Although hematological toxicities, particularly neutropenia, were severe, AMR showed excellent anti-tumor activity, not only in the S, but also in the R cases, as shown in previous phase II studies. These results warrant further evaluation of AMR in the second-line setting, and also in the first-line setting in both limited- and extensive-stage disease. We conducted a phase II study to assess the efficacy of consolidation chemotherapy with AMR after standard chemoradiation in limited-stage SCLC.

Treatment options for small cell lung cancer - do we have more choice?

Small cell lung cancer (SCLC) is a significant health problem worldwide because of its high propensity for relapse. This review discusses existing and future therapies for the treatment of SCLC.

Current status of second-line treatment and novel therapies for small cell lung cancer

Despite high response rates to first-line standard treatment, the great majority of patients with small cell lung cancer (SCLC) will relapse and succumb to their disease rather quickly. In the context of salvage therapy, symptom palliation and quality-of-life improvements, besides survival prolongation, are primary treatment endpoints. A variety of single-agent and multi-agent chemotherapy regimens have been tested with limited success in patients with recurrent SCLC. A number of combination regimens have demonstrated high response rates in second-line settings, but these can be considered only for patients with good performance status. Treatment outcome depends on many factors, including type of response to first-line therapy, treatment-free interval, and performance status. Currently, topotecan represents an effective, tolerable therapeutic option and is the only agent approved for this indication. The management of patients with recurrent disease remains an area of active research. This review provides an update of clinical research on second-line chemotherapy of SCLC and of recent results obtained with novel molecular targeted approaches in both first- and second-line therapy.

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.

Fast, hungry and unstable: finding the Achilles' heel of small-cell lung cancer

Over 95% of patients with small-cell lung cancer (SCLC) die within five years of diagnosis. The standard of care and the dismal prognosis for this disease have not changed significantly over the past 25 years. Some of the characteristics of SCLC that have defined it as a particularly virulent form of cancer -- rapid proliferation, excessive metabolic and angiogenic dependence, apoptotic imbalance and genetic instability -- are now being pursued as tumor-specific targets for intervention both in preclinical and early phase clinical studies. Here, we summarize areas of ongoing anti-cancer drug development, including classes of agents that target essential pathways regulating proliferation, angiogenesis, apoptotic resistance, chromosomal and protein stability, and cell-cell and cell-matrix interaction.

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.