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Alternating with Amrubicin Plus and Weekly Administration of Plus Cisplatin for Extensive-stage Small Cell

RINTARO NORO1*, AKINOBU YOSHIMURA1,2*, KAZUO YAMAMOTO1, AKIHIKO MIYANAGA1, HIDEAKI MIZUTANI1, YUJI MINEGISHI1, MASAHIRO SEIKE1, KAORU KUBOTA1, SEIJI KOSAIHIRA3, MITSUNORI HINO3, MASAHIRO ANDO4, KOICHIRO NOMURA5, TETSUYA OKANO6, KUNIHIKO KOBAYASHI6, KAZUTSUGU UEMATSU7, AKIHIKO GEMMA1 and The East Japan Chesters Group

1Division of Pulmonary Medicine, Infectious Diseases and Oncology, Department of Internal Medicine, Nippon Medical School, Tokyo, Japan; 2Department of Clinical Oncology, Tokyo Medical University Hospital, Tokyo, Japan; 3Division of Internal Medicine, Nippon Medical School Chiba Hokusoh Hospital, Imzai City, Chiba, Japan; 4Division of Internal Medicine, Tsuboi Cancer Center Hospital, Koriyama City, Fukushima, Japan; 5Department of Respiratory Medicine, Tokyo Metropolitan Hiroo General Hospital, Tokyo, Japan; 6Department of Respiratory Medicine, Saitama International Medical Center, Saitama Medical University, Hidaka City, Saitama, Japan; 7Division of Pulmonary Medicine, Saitama Medical Center, Saitama Medical University, Kawagoe City, Saitama, Japan

Abstract. Background: A phase II study was conducted in anorexia, diarrhea, febrile neutropenia and infection were order to determine the tumor efficacy and tolerance of observed in 5 (25%), 2 (10%), 2 (10%) and 2 (10%) alternating chemotherapy for extensive-stage small cell lung patients, respectively. No treatment-related death occurred cancer (ED-SCLC). Patients and Methods: Twenty patients during either regimen. Conclusion: The novel alternating with previously-untreated ED-SCLC were enrolled in the non-cross-resistant chemotherapy was probably active study. At least four courses of chemotherapy consisting of against ED-SCLC and had acceptable toxicities. Further alternation of two drug combinations were given: alternating evaluation of this treatment for ED-SCLC in randomized cycles of amrubicin and cisplatin with weekly administration phase III trials is warranted. of irinotecan and cisplatin at 3- or 4-week intervals. Results: The overall response rate was 85.0% (17/20). The median Combinations of plus cisplatin (EP) or duration of overall survival and progression-free survival have been recognized as the standard regimens for therapy were 359 days and 227 days, respectively. Hematological of extensive-stage small cell lung cancer (ED-SCLC). toxicity was the main adverse event. Grade 3 or 4 Despite the substantial initial sensitivity of SCLC to neutropenia, thrombocytopenia and anemia were observed in chemotherapy, a high rate of relapse has been observed. In 20 (100%), 4 (20%) and 6 (30%) patients, respectively. With order to overcome this barrier for successful treatment, other regard to non-hematological adverse events, grade 3 or 4 therapeutic approaches were investigated in the early 1990s, including alternating non-cross-resistant, high-dose and dose- intensive (1-5). Combination chemotherapy *These Authors contributed equally to this work. of alternating , , and (CAV) with EP (CAV/EP), based upon the Correspondence to: Akinobu Yoshimura, MD, Ph.D., Department of mathematical model developed by Goldie et al. (6), also Clinical Oncology, Tokyo Medical University Hospital, 6-7-1, provided no therapeutic advantage compared with either Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan. Tel: +81 CAV- or EP-alone in randomized studies (1, 2). It was 333426111 Ext. 2161, Fax: +81 333426211, e-mail: ay1004@tokyo- med.ac.jp concluded that these failed attempts could be ascribed to incomplete non-cross-resistance between CAV and EP, thus, Key Words: Extensive-stage small cell lung cancer, alternating further trials in this setting should await the development of chemotherapy, amrubicin, irinotecan, cisplatin. regimens that are more non-cross-resistant (1, 2).

0250-7005/2013 $2.00+.40 1117 ANTICANCER RESEARCH 33: 1117-1124 (2013)

Both new drug regimens and alternative drug doses and urine analysis, ECG and echocardiography. Patients were monitored schedules are thought to be treatment options under clinical weekly throughout treatment by physical examination, recording of evaluation for patients with ED-SCLC. Irinotecan toxicities, complete blood cell count with differential, and serum chemistry determination. Radiographic evaluation included chest X- hydrochloride (CPT-11), a topoisomerase-I inhibitor, is ray, computed tomographic scans of brain, chest and abdomen, and effective as a single agent against SCLC, and the combination radionuclide bone scan. This study was approved by the Institutional regimen of irinotecan and cisplatin (IP) also demonstrates Review Boards of all participating hospitals. acceptable activity for ED-SCLC (7, 8). Ando et al. reported that weekly administration of cisplatin in a single dose in Treatment. A regimen of AP was alternated with weekly IP combination with CPT-11 was also effective against treatments given at 3- or 4-week intervals. Amrubicin was refractory and relapsed SCLC (9). Therefore, we conducted administered at 40 mg/m2 over five minutes by intravenous (i.v.) a phase II study of combination chemotherapy of alternating injection on days 1 to 3 and cisplatin was sequentially administered at 60 mg/m2 over two hours by i.v. infusion on day 1 with adequate etoposide and carboplatin with weekly administration of IP hydration before and after treatment and with furosemide diuresis. for ED-SCLC, which demonstrated moderate tumor efficacy On days 1, 8 and 15, CPT-11 was administered at 60 mg/m2 over and an acceptable safety profile (10). two hours by i.v. infusion and cisplatin was sequentially given at Amrubicin is a novel, completely synthetic 9- 30 mg/m2 over half an hour by i.v. infusion with adequate aminoanthracycline derivative, which inhibits purified human hydration and furosemide diuresis. Standard antiemetic topoisomerase-II (11). Amrubicin demonstrates excellent included 5-hydroxytryptamine (HT) 3-receptor antagonist, activity for ED-SCLC, both as single-agent and in corticosteroids and neurokinin-1 receptor antagonists given half an hour before administration of amrubicin or CPT-11. Administration combination with cisplatin (AP) (12, 13). of granulocyte colony-stimulating factor (G-CSF) was permitted It is assumed that CPT-11 and amrubicin are non-cross- when grade 4 neutropenia or febrile neutropenia with grade 3 resistant with each other due to their different mechanisms neutropenia were observed and preventive use of G-CSF was of action. Therefore, we conducted a phase II study in ED- allowed when grade 4 neutropenia was detected during the previous SCLC to determine the tumor efficacy and tolerance of a chemotherapy. new alternating non-cross-resistant chemotherapy, consisting Dosage modifications of each drug were made based upon of the alternation of AP with weekly administration of IP. hematological, renal, and gastrointestinal toxicity according to the NCI-Common Toxicity Criteria version 3.0 (14). If one of the therapeutic regimens demonstrated no tumor shrinkage, it was Patients and Methods discontinued and the effective one was continued. The patients underwent at least four cycles of chemotherapy unless disease Patients. Eligibility criteria for study entry included histologically- progression or severe toxicities including renal, gastrointestinal or cytologically-confirmed SCLC; extensive disease (defined as (especially diarrhea) and others were observed. distant metastasis, contralateral hilum node metastasis, or both; In second-line treatment after recurrence, active chemotherapies those patients with malignant pleural effusion alone were also in the first-line treatment, AP and/or IP, were administered to included); presence of measurable lesions; no prior therapy; age 20 patients with sensitive-relapse SCLC, defined as treatment-free to 75 years; an Eastern Cooperative Oncology Group performance interval (TFI) ≥90 days. Other treatment options including status of 0 to 2; adequate organ function, defined as a white blood prophylactic cranial irradiation etc. after the completion of the first- cell count of at least 4,000/μl and less than 12,000/μl, neutrophil line treatment were not prescribed. count of at least 4,000/μl, a platelet count of at least 100,000/μl, a hemoglobin level of at least 9.5 g/dl, a bilirubin level of less than Evaluation. Toxicity was evaluated after each cycle according to 1.5 mg/dl, serum transaminase and alkaline phosphatase levels of NCI-Common Toxicity Criteria version 3.0 (14). Patients were less than twice the upper limit of normal, a creatinine value of less evaluated for response according to Response Evaluation Criteria in than 1.5 mg/dl; a 24 hour-creatinine clearance level of at least Solid Tumors (RECIST) version 1.0 guideline (15). In brief, 50 ml/min; PaO2 level of at least 70 Torr; no abnormality requiring complete response (CR) was defined as complete disappearance of treatment on electrocardiogram (ECG); left ventricle ejection all detectable tumor lesions for at least four weeks, with fraction of at least 60%; a life expectancy of at least three months. documented disappearance of all targeted lesions by physical Written informed consent was obtained from each patient. Patients examination and radiographic imaging and no appearance of new who were excluded had one or more of the following: active lesions. Partial response (PR) was indicated by a decrease of 30% or infection, other active malignant disease, pulmonary fibrosis or greater in the sum of the longest diameter of target lesions compared interstitial pneumonia, ileus, intractable diarrhea, cardiac failure, with the baseline sum of them, the required non-progression of in medical history of abnormal cardiac function, uncontrolled non-target lesions and no concomitant growth of new lesions for at complications (diabetes mellitus, bronchial asthma, etc.), least four weeks. Progressive disease (PD) was indicated by an at symptomatic brain metastases, massive ascites or pleural effusion, least a 20% increase in the sum of the longest diameter of target carcinomatous pericarditis, pregnancy/nursing women, or medical lesions, taking as reference the smallest sum of the longest diameter history of drug hypersensitivity. recorded since the treatment started and/or unequivocal progression Pre-registration evaluations consisted of a complete medical of existing non-target lesions and/or new lesions. Stable disease history, physical examination, recording of performance status, (SD) was indicated by neither sufficient decrease in the sum of the complete blood cell count with differential, serum biochemistry, longest diameter of target lesions to qualify for PR nor sufficient

1118 Noro et al: Alternating Chemotherapy for Extensive-stage Small Cell Lung Cancer

Table I. Patient characterisitics and drug delivery. Table II. Tumor response and survival.

Eligible patients, n 20 n% Median age (range), years 65 (47-74) Gender (M/F) 14/6 Response ECOG PS (0-1/2) 18/2 Complete response 4 20 ED 19 Partial response 13 65 PE 1 Stable disease 1 5 Chemotherapy cycles Progressive disease 2 10 12Overall response rate 17 85 (95% CI=77-93) 21Disease control rate 18 90 (95% CI=83.3-96.7) 31Survival 411Median survival time (days) 359 53Median PFS (days) 227 621-Year OS (%) 40 (95% CI=22.5-70.4)

ED, Extensive disease, patients with distant metastasis, contralateral ED, Extensive disease, patients with distant metastasis, contralateral hilum node metastasis, or both; PE, patients with malignant pleural hilum node metastasis, or both; PE, patients with malignant pleural effusion alone; M, male; F, female; ECOG, Eastern Cooperative effusion alone; PFS, progression-free survival; OS, overall survival; Oncology Group. 95% CI, 95% confidence interval.

increase in the sum of the longest diameter of target lesions to were 19 patients with distant metastases, contralateral hilum qualify for PD, the required non-progression of in non-target lesions node metastasis, or both, and one patient with malignant and no concomitant growth of new lesions for at least four weeks. pleural effusion alone. The median number of chemotherapy A full staging evaluation was performed before treatment cycles was four (range 1-6). Sixteen patients underwent the initiation, as described above, and a follow-up evaluation was performed after each course of chemotherapy was completed. The planned four or more cycles of chemotherapy, although four response rate was confirmed by objective extramural review. patients underwent three or fewer cycles because of disease progression (two patients), initiation of thoracic radiotherapy Statistical analysis. The primary end-point of this study was the without disease progression (one patient) and severe adverse objective response rate (ORR); secondary end-points were events of syndrome of inappropriate antidiuretic hormone determination of overall survival (OS), progression-free survival secretion (SIADH) (one patient). (PFS) and evaluation of toxicity. OS was calculated using the The ORR and CR were 85% (17/20, 95% confidence Kaplan-Meier method and was calculated from the day of start of treatment until death by any cause; surviving patients were censored interval (CI)=77 to 93%) and 20% (4/20, 95% CI=11.1 to at the last date of follow-up. PFS was calculated from the day of 28.9%), respectively (Table II). The disease control rate was treatment until disease progression or death from any cause. 90% (18/20, 95% CI=83.3-96.7%), whereas disease Assuming that an 80% ORR in eligible patients would indicate progression was observed in two patients. At the time of potential usefulness, whereas a 60% ORR would constitute the analysis, 15 patients had died, while three were still alive and lower limit of interest, with α=0.05 and β=0.20, the estimated two were lost to follow-up. The overall median survival time accrual was 35 patients. Interim analysis was implemented when (MST) was 359 days, and one-year OS was 40% (95% twenty patients were enrolled. CI=22.5 to 70.4%) (Figure 1, Table II). The median PFS time Results was 227 days (Figure 1). Overall adverse events are demonstrated in Table III. A total of twenty-one consecutive patients with previously- Hematological toxicity was the main event. Grade 3 or 4 untreated ED-SCLC were enrolled from two institutions neutropenia, thrombocytopenia and anemia were observed in between October 2005 and May 2012. At the time of interim 20, 4 and 6 patients, respectively. With regard to non- analysis, the committee for this study decided to stop hematological adverse events, grade 3 or 4 anorexia, enrollment in the clinical trial because of the qualitative issue diarrhea, febrile neutropenia and infection were observed in attributable to the slowness of enrollment. Twenty patients 5, 2, 2 and 2 patients, respectively. Nausea/vomiting, were eligible and assessable for efficacy and safety of the syndrome of inappropriate antidiuretic hormone (SIADH) treatment; one patient was not assessable because he did not and hypertension which was due to worsening of concurrent undergo chemotherapy. Patient characteristics of these 20 disease, were observed in one case each. Adverse events are patients are shown in Table I. There were 14 men and six shown according to the course of each treatment in Table IV. women, with a median age of 65 years (range; 47-74), and Hematological adverse events were more common during the 18 patients had a good performance status of 0 or 1. There AP regimen than during the IP one. Grade 3 or 4 neutropenia

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Table III. Adverse events (n=20) experienced due to combination chemotherapy.

Grade 3 Grade 4 ≥Grade 3 (%)

Hematological Neutropenia 2 18 100.0 Thrombocytopenia 3 1 20.0 Anemia 3 3 30.0 Non-hematological Diarrhea 2 0 10.0 Nausea/vomiting 1 0 5.0 Anorexia 5 0 25.0 Febrile neutropenia 2 0 10.0 Infection* 2 0 10.0 Hypertension 1 0 5.0 SIADH 0 1 5.0

SIADH: Syndrome of inappropriate antidiuretic hormone secretion. *Two patients experienced grade 3 pneumonia.

SCLC, and it is presumed that these drugs are potentially non-cross-resistant with each other because they have different mechanisms of action. It is reported that resistance to topoisomerase-II inhibitors is associated with active efflux of drug from tumor by P- glycoprotein (P-gp), reducing cellular content and/or activity of topoisomerase-II, and reducing in the expression level of mismatch repair genes (18, 19). Increased multidrug- Figure 1. Kaplan-Meier curves for overall survival (a) and progression- free survival (b) of patients treated with alternating chemotherapy with resistance (MDR)-1 gene expression and P-gp activity amrubicin plus cisplatin and weekly administration of irinotecan plus provide acquired resistance to amrubicin (20). Furthermore, cisplatin. It is generally thought that resistance to topoisomerase-I inhibitors is caused by the following mechanisms: inadequate accumulation of drug in the tumor, resistance-conferring alterations in topoisomerase-I, or alterations in the cellular is the majority of patients during the AP regimen, response to topoisomerase- I- CPT interaction (21, 22). respectively. By contrast, grade 3 or 4 neutropenia, With regard to cross-resistance between topoisomerase-I thrombocytopenia and anemia were less frequent during the and -II inhibitors, Chauvier et al. showed that MCF7/VP and IP regimen. With regard to non-hematological adverse MCF7/DOX breast carcinoma cells, which are resistant to events, grade 3 or 4 anorexia (11.9%, 5/42) and febrile both etoposide and doxorubicin and express multidrug neutropenia (4.8%, 2/42) occurred frequently during the AP resistance-associated protein (MRP-1), were resistant to CPT- regimen. On the contrary, severe diarrhea (8.1%, 3/37) was 11 (23). However, Schneider et al. reported that MCF7/VP notable with the IP regimen. No treatment-related death cells, selected for resistance to etoposide, exhibited no cross- occurred during either regimen. resistance to (24). Jensen et al. also revealed there is no cross-resistance to CPT-11 in H69/DAU small cell Discussion lung cancer cell line, which is a multidrug-resistant cell line with combination of MDR1 and MRP-1 overexpression (25). Amrubicin is a 9-aminoanthracycline derivative and induces No conclusive evidence has shown there to be cross-resistance cell growth inhibition by stabilizing protein – DNA between topoisomerase-I and -II inhibitors. Furthermore, it has complexes followed by double-stranded DNA breaks, which been demonstrated that sequential and simultaneous are mediated by topoisomerase-II (16). On the other hand, association of camptothecin and provides CPT-11 is a camptothecin analog with strong antitumor complete reversal of resistance, showing a synergistic effect activity and is a strong inhibitor of topoisomerase-I in in daunorubicin-resistant cells (23). In a similar manner, mammalian cells (17). Both agents are effective against homocamptothecin, a camptothecin analogue, has been shown

1120 Noro et al: Alternating Chemotherapy for Extensive-stage Small Cell Lung Cancer

Table IV. Adverse events according to treatment course for each regimen.

Amrubicin/cisplatin (42 courses) Irinotecan/cisplatin (37 courses)

Grade 3 Grade 4 ≥Grade 3 (%) Grade 3 Grade 4 ≥Grade 3 (%)

Hematological Neutropenia 11 24 83.3 8 3 29.7 Thrombocytopenia 3 1 9.5 0 0 0.0 Anemia 5 2 16.7 5 1 16.2 Non-hematological Diarrhea 0 0 0.0 3 0 8.1 Nausea/vomiting 1 0 2.4 0 0 0.0 Anorexia 5 0 11.9 2 0 5.4 Febrile neutropenia 2 0 4.8 0 0 0.0 Infection* 1 0 2.4 1 0 2.7 Hypertension 2 0 4.8 2 0 5.4 SIADH 0 1 2.4 0 0 0.0

SIADH: Syndrome of inappropriate antidiuretic hormone secretion. *Two patients experienced grade 3 pneumonia.

to increase nuclear daunorubicin accumulation and potentiate hematological toxicities on AP was similar to that observed daunorubicin activity in MCF7/DOX breast carcinoma cells, in earlier phase I-II trials for previously-untreated SCLC implying a synergistic mechanism between these two (26). (13). In non-hematological severe adverse events on AP, the In this study, we have demonstrated the efficacy of a novel incidence of anorexia (11.9%) was lower and that of febrile non-cross-resistant chemotherapy of alternating AP with neutropenia (4.8%) was higher than that previously observed weekly administration of IP for patients with previously- in earlier phase I-II trials (13). On the other hand, the untreated ED-SCLC, as shown by a response rate of 85%, incidence of hematological toxicities on IP was different overall MST of 359 days, median PFS time of 227 days and from that observed previously in the phase III trials because one-year overall survival rate of 40%. In previous phase II and of weekly administration of cisplatin. The incidence of grade III studies, involving patients with previously-untreated ED- 3 or 4 neutropenia (29.7%) and thrombocytopenia (0%) was SCLC, combination chemotherapies of EP, which are presently lower than previously reported (27, 28). In non- recognized as standard regimens, and IP have demonstrated hematological severe adverse events, diarrhea (8.1%) response rates of 44 to 68% and 48 to 84%, overall MST of frequently occurred during the IP regimen, although the 9.1 to 10.2 months and 9.3 to 12.8 months, median PFS time of incidence rate was lower than in previous phase III trials (27, 4.6 to 5.2 months and 4.1 to 6.9 months and one-year OS rate 28). Treatment was discontinued in one patient due to severe of 34 to 38% and 35 to 58%, respectively (27-29). Regarding adverse events of SIADH. However, no treatment-related the IP regimen, five trials and two meta-analyses evaluated the death occurred during either regimen. combination of EP versus IP. Only one of the trials showed the In conclusion, the novel alternating non-cross-resistant superiority of the combination chemotherapy of IP. On the chemotherapy in patients with ED-SCLC, consisting of an other hand, in previous phase I-II study in previously untreated alternation of amrubicin and cisplatin with weekly patients with ED-SCLC, the combination chemotherapy of AP administration of CPT-11 and cisplatin, was probably active led to a response rate of 88%, overall MST of 13.6 months, against ED-SCLC and showed acceptable toxicities. Further and one-year OS rate of 56.1% (13). Therefore, we considered evaluation of this treatment for ED-SCLC in randomized that this non-cross-resistant chemotherapy shown moderate phase III trials is warranted. tumor efficacy. Hematological toxicities were the common adverse events Conflicts of Interest in this study; toxicities of grade 3 or 4 including neutropenia, thrombocytopenia and anemia were observed. Non- None declared. hematological severe adverse events such as anorexia, diarrhea, febrile neutropenia, infection and nausea/vomiting Acknowledgements also occurred. According to the course of each treatment, hematological adverse events were more common during the We thank the the East Japan Chesters Group members for their AP regimen than during the IP one. The incidence of dedication and cooperation throughout the course of this work.

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