Phase II Study of Sequential Triplet Chemotherapy, Irinotecan and Cisplatin Followed by Amrubicin, in Patients with Extensive-Stage Small Cell Lung Cancer: West Japan Thoracic Oncology Group Study 0301

Randomized phase 2 study comparing irinotecan versus amrubicin as maintenance therapy after first-line induction therapy for extensive disease small cell lung cancer (HOT1401/NJLCG1401)

Background

A cisplatin plus irinotecan (CPT‐11) regimen is used for patients with extensive disease small cell lung cancer (ED‐SCLC). Amrubicin (AMR) is primarily used for relapsed SCLC. The HOT1401/NJLCG1401 trial, an open‐label randomized phase II trial, was designed to assess the benefit of maintenance therapy in patients with ED‐SCLC who responded to induction therapy.

Methods

Patients with histologically‐ or cytologically‐confirmed ED‐SCLC were included and were treated with an induction therapy of four cycles of cisplatin (60 mg/m² on day 1) plus CPT‐11 (60 mg/m² on days 1, 8, and 15) every four weeks. After induction therapy, patients who had nonprogressive disease were randomized to receive either maintenance CPT‐11 (60 mg/m² on days 1 and 8) every three weeks, or AMR (35 mg/m² on days 1–3) every three weeks.

Results

A total of 34 patients were enrolled; 20 patients had progressive disease or received incomplete induction chemotherapy. Finally, 14 patients were randomly assigned to receive CPT‐11 (n = 7) or AMR (n = 7). This study was terminated prematurely because of low patient accrual. The overall objective response rate was 73%, the median PFS was 5.7 months (95% confidence interval [CI]: 3.6–11.8), and the median overall survival was 20.1 months (95% CI: 13.7–not reached). No statistically significant difference in progression‐free survival (PFS) were noted between patients treated with CPT‐11 and those treated with AMR. There were no treatment‐related deaths in this study.

Conclusions

Maintenance therapy with CPT‐11 or AMR after induction therapy might be effective in some patients.

Randomized phase III trial of amrubicin/cisplatin versus etoposide/cisplatin as first-line treatment for extensive small-cell lung cancer

BACKGROUND

Extensive-disease small-cell lung cancer (ED-SCLC) is characterized by rapid progression and relapse, despite high initial response rates to chemotherapy. The primary objective of this trial was to demonstrate the non-inferiority of amrubicin and cisplatin (AP) combination therapy compared with the standard first-line regimen of etoposide and cisplatin (EP) for previously untreated ED-SCLC in a Chinese population. When non-inferiority was verified, the objective was switched from non-inferiority to superiority.

METHODS

From June 2008 to July 2010, 300 patients were enrolled and randomly assigned at a 1:1 ratio to AP and EP groups. AP-treated patients received cisplatin (60 mg/m(2), day 1) and amrubicin (40 mg/m(2), days 1-3) once every 21 days. EP-treated patients received cisplatin (80 mg/m(2), day 1) and etoposide (100 mg/m(2), days 1-3) once every 21 days. Treatment was continued for four to six cycles, except in cases of progressive disease or toxicity, and patient refusal.

RESULTS

Median overall survival (OS) for AP vs. EP treatment was 11.8 vs. 10.3 months (p = 0.08), respectively, demonstrating non-inferiority of AP to EP (AP group: 95% confidence interval for hazard ratio 0.63-1.03 months). Median progression-free survival and overall response rates for AP vs. EP groups were 6.8 vs. 5.7 months (p = 0.35) and 69.8% vs. 57.3%, respectively. Drug-related adverse events in both groups were similar, with neutropenia being the most frequent (AP 54.4%; EP 44.0%). Leukopenia, pyrexia, and fatigue were more prevalent in the AP group, but all were clinically reversible and manageable.

CONCLUSIONS

AP therapy demonstrated non-inferiority to EP therapy, prolonging OS for 1.5 months, but this difference was not statistically significant; thus we propose AP as a promising treatment option for ED-SCLC in China.

TRIAL REGISTRATION

This trial was registered on 10 April 2008 (ClinicalTrials.gov NCT00660504).

Chemotherapy advances in small-cell lung cancer

Although chemotherapeutic advances have recently been heralded in lung adenocarcinomas, such success with small-cell lung cancer (SCLC) has been ominously absent. Indeed, the dismal outlook of this disease is exemplified by the failure of any significant advances in first line therapy since the introduction of the current standard platinum-etoposide doublet over 30 years ago. Moreover, such sluggish progress is compounded by the dearth of FDA-approved agents for patients with relapsed disease. However, over the past decade, novel formulations of drug classes commonly used in SCLC (e.g. topoisomerase inhibitors, anthracyclines, alkylating and platinum agents) are emerging as potential alternatives that could effectively add to the armamentarium of agents currently at our disposal. This review is introduced with an overview on the historical development of chemotherapeutic regimens used in this disease and followed by the recent encouraging advances witnessed in clinical trials with drugs such as amrubicin and belotecan which are forging new horizons for future treatment algorithms.

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.

Management of small cell lung cancer: recent developments for optimal care

Small cell lung cancer (SCLC) represents approximately 13% of all lung cancer diagnoses and the incidence has reduced over the last 20 years. Treatment of SCLC remains challenging because of its rapid growth, early dissemination and development of drug resistance during the course of the disease. Chemotherapy remains the cornerstone of treatment for limited (LD) and extensive disease (ED), with concurrent chemotherapy and radical thoracic radiotherapy representing the best treatment option for fit patients with LD. Platinum-based chemotherapy is the treatment of choice in fit patients with good organ function, and the radiosensitizing effect of cisplatin is critically important for concurrent chemoradiotherapy in LD. Anthracycline-containing regimens represent a viable alternative for patients where platinum-based chemotherapy is contraindicated. Patients who relapse or progress after first-line chemotherapy have a very poor prognosis. Second-line therapy may produce a modest clinical benefit. Maintenance chemotherapy has not been shown to convincingly improve outcomes for SCLC. A number of targeted agents have been investigated in LD and ED, mostly in unselected populations, with disappointing results. Prophylactic cranial irradiation has been shown to reduce the incidence of brain metastases and prolong survival for both LD and ED without negative impact on quality of life (QOL) and cognitive function. Ongoing trials will shed some light on the impact of thoracic radiotherapy on QOL, symptom control and survival in ED SCLC patients who benefitted from first-line chemotherapy.

Chemotherapy for small cell lung cancer: a comprehensive review

Combination chemotherapy is the current strategy of choice for treatment of small cell lung cancer (SCLC). Platinum containing combination regimens are superior to non-platinum regimens in limited stage-SCLC and possibly also in extensive stage-SCLC as first and second-line treatments. The addition of ifosfamide to platinum containing regimens may improve the outcome but at the price of increased toxicity. Suboptimal doses of chemotherapy result in inferior survival. Early intensified, accelerated and high-dose chemotherapy gave conflicting results and is not considered a standard option outside of clinical trials. A number of newer agents have provided promising results when used in combination regimens, for example, gemcitabine, irinotecan and topotecan. However, more studies are required to appropriately evaluate them. There is a definitive role for radiotherapy in LD-SCLC. However, timing and schedule are subject to further research. Novel approaches are currently being investigated in the hope of improving outcome.

Current management of small cell lung cancer

Confined to one side of the chest, limited stage small cell lung cancer is treated with a combination of chemotherapy and radiotherapy, yet has a long-term survival rate of only 15%. Extensive stage disease has initial response rates to chemotherapy exceeding 70%. However, the disease almost invariably progresses and becomes fatal. Many recent clinical trials have failed to show superiority of newer chemotherapeutics or targeted therapies compared with the standard chemotherapy backbone of platinum plus etoposide. Numerous promising targeted therapies and other agents are still in development.

Thoracic radiation therapy improves the overall survival of patients with extensive-stage small cell lung cancer with distant metastasis

BACKGROUND

The authors conducted a retrospective study to evaluate the effects of thoracic radiation therapy (TRT) for patients with extensive-stage small cell lung cancer (ED-SCLC).

METHODS

Between January 2003 and December 2006, the records of 119 patients who were diagnosed with ED-SCLC (all with distant metastasis [M1]) were included in the study. Sixty patients received chemotherapy (ChT) and TRT (ChT/TRT), and 59 patients received ChT alone. The ChT regimens consisted of either carboplatin and etoposide (CE) or cisplatin and etoposide (PE). The total dose of TRT ranged from 40 to 60 grays (Gy) at 1.8 to 2.0 Gy per fraction.

RESULTS

For the entire group, the median survival was 13 months, and the 2-year and 5-year overall survival (OS) rates were 26.1% and 6.5%, respectively. The median survival and the 2-year and 5-year OS rates were 17 months, 35%, and 7.1%, respectively, in the ChT/TRT group and 9.3 months, 17%, and 5.1%, respectively, in the ChT group (P = .014). However, this improvement was achieved at the expense of low toxicity. Multivariate analysis revealed that receiving ≥4 cycles of ChT (P = .032) and TRT (P = .005) were favorable prognostic factors for OS. Of all toxicities, only high-grade leucopenia (grade >3) was more frequent in the ChT/TRT group.

CONCLUSIONS

The addition of TRT to ChT improved the OS of patients with ED-SCLC. Furthermore, receiving ≥4 cycles of ChT and TRT were independent, favorable prognostic factors for OS.