Kiyoshi Komuta

Polymorphisms of CYP2D6 gene and gefitinib-induced hepatotoxicity.

INTRODUCTION Gefitinib induces severe hepatotoxicity in approximately a quarter of Japanese patients with epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC). Gefitinib is metabolized by cytochrome P450 (CYP) enzymes--including CYP3A4/5, CYP1A1, and CYP2D6--in the liver. We hypothesized that polymorphisms of the CYP2D6 gene may account for gefitinib-induced hepatotoxicity. PATIENTS AND METHODS Polymorphisms of the CYP2D6 gene were analyzed in 55 patients with NSCLC who experienced grade ≥ 2 transaminase elevation from gefitinib. The distribution of the CYP2D6 genotype was compared with that of the healthy Japanese population. The correlations between the nonfunctional allele *5 or the reduced-function allele *10 and hepatotoxicity-related clinical factors were also examined. RESULTS The distribution of the CYP2D6 genotype in the study participants was not different from that of the general Japanese population, reported previously. Existence of allele *5 or *10 did not correlate with clinical factors such as onset of hepatotoxicity within 2 months, grade ≥ 3 serum transaminase elevation, and tolerability to dose reduction or rechallenge of gefitinib. However, in 7 patients taking CYP3A4-inhibitory drugs, rechallenge of gefitinib again caused hepatotoxicity in 4 patients with allele *5 or *10 but not in 3 patients with normal alleles (P = .029). Moreover, switching to erlotinib did not cause hepatotoxicity in any of 17 patients with allele *5 or *10 but did in 3 of 8 patients without these alleles (P = .024). CONCLUSION Reduced function of CYP2D6 may partly account for gefitinib-induced hepatotoxicity when CYP3A4 is inhibited. Erlotinib could be safely used in patients with decreased CYP2D6 activity even after they experienced gefitinib-induced hepatotoxicity.

Induction of tumoricidal macrophages from bone marrow cells of normal mice or mice bearing a colony-stimulating-factor-producing tumor.

SummaryNonadherent cells of the bone marrow of C3H/HeN mice were incubated for 3 days with the culture supernatant of an L-929 cell line containing macrophage-colony-stimulating factor. Approximately, 70% of the cells became phagocytic, adherent to plastic dishes and positive for nonspecific esterase staining. The adherent cells exhibited a weak tumoricidal activity against MM48 syngeneic mammary carcinoma cells, and the cytotoxicity was strongly augmented by the addition of bacterial lipopolysaccharide to the cytotoxicity assay. The cytotoxicity induced by lipopolysaccharide was also shown to be mediated by Thy1.2− and asialo-GM1+ cells, and was abrogated by the addition of carrageenan. Macrophage-colony-stimulating-factor-producing (D66) and nonproducing (A23) variants were separated from the MM48 tumor line in in vitro culture following limiting dilution. There was no difference between these two variants in either the in vitro growth rate or the susceptibility to macrophage-mediated cytotoxicity. C3H/HeN mice inoculated i.p. with D66 survived longer than did those inoculated i.p. with A23. C3H/HeN mice bearing D66 or A23 as an ascitic form were given i.p. injections of Nocardia rubra cell wall skeleton (N-CWS). N-CWS significantly prolonged the survival period of mice bearing D66, whereas it exhibited no apparent antitumor effect on mice bearing A23. The increase in the cell number of D66 in the peritoneal cavity was significantly retarded, compared with that of A23. In contrast, the number of peritoneal macrophages increased more in D66-bearing mice than in A23-bearing mice. The increase in the peritoneal macrophage number was further augmented by an i.p. injection of N-CWS. Peritoneal macrophages of D66-bearing mice exhibited apparent tumoricidal activity against MM48 tumor cells in the presence of lipopolysaccharide, and the cytotoxicity was significantly augmented by i.p. injection of N-CWS. On the other hand, the responsiveness of peritoneal macrophages to lipopolysaccharide was found to be poor in A23-bearing mice and the tumoricidal activity was only weakly augmented by N-CWS. These results strongly suggest that M-CSF plays an important role not only in the maturation of macrophage progenitors but also in the induction and the accumulation of activated macrophages.

A retrospective analysis of 335 Japanese lung cancer patients who responded to initial gefitinib treatment.

BACKGROUND Gefitinib treatment results in considerably better progression-free survival compared with that of platinum doublets in the first line treatment of nonsmall-cell lung cancer (NSCLC) carrying an activating epidermal growth factor receptor (EGFR) mutation. Some patients who respond to gefitinib have an overall survival (OS) of more than 5 years, whereas other initial responders do less well. Although there has been considerable effort made to elucidate the mechanisms of acquired resistance, there have only been a few studies that addressed the effect of clinical backgrounds and treatment histories on the survival of the patients who had responded to an EGFR-tyrosine kinase inhibitor (TKI). In this study, we especially focused on the clinical benefit of EGFR-TKI administration after progression. PATIENTS AND METHODS We retrospectively analyzed consecutive patients with advanced NSCLC who were diagnosed before October 2010, treated with gefitinib after July 2002, and responded to it. The primary objective of this study was to evaluate how clinical backgrounds and treatment histories influence survival of the patients who respond to gefitinib. The secondary objectives were to evaluate the safety of long-term gefitinib use and to establish the optimal treatment sequence using a dynamic treatment regimen analysis (DTRA). RESULTS A total of 335 patients were recruited. Twenty-eight (8.4%) patients survived more than 5 years. Sixty-five and 93 patients received gefitinib as rechallenge and beyond progressive disease (BPD), respectively. A statistically significant difference in OS was observed between the patients who underwent gefitinib rechallenge and those who did not rechallenge (median: 1272 days vs. 774 days; p < 0.001), a result supported by a DTRA. Patients treated with gefitinib BPD also showed a tendency of longer survival. CONCLUSIONS Gefitinib rechallenge and BPD played a central role in long term survival of the patients who initially responded to gefitinib.

Efficacy and safety of erlotinib in elderly patients in the phase IV POLARSTAR surveillance study of Japanese patients with non-small-cell lung cancer.

OBJECTIVE More tolerable treatment options are needed for the large number of elderly patients with non-small-cell lung cancer (NSCLC). An analysis of the phase IV POLARSTAR surveillance study examined the safety and efficacy of erlotinib in elderly Japanese patients with previously treated NSCLC. MATERIALS AND METHODS From December 2007 to October 2009, all erlotinib-treated patients with unresectable, recurrent/advanced NSCLC in Japan were enrolled. Efficacy and safety data were stratified by age (<75 years, 75-84 years, ≥85 years). Kaplan-Meier methodology was used to estimate median progression-free survival (PFS). Safety data were collected with a focus on interstitial lung disease (ILD). RESULTS A total of 9907 patients were eligible for safety assessment (<75 years, n=7848; 75-84 years, n=1911; ≥85 years, n=148) and 9651 for efficacy assessment (<75 years, n=7701; 75-84 years, n=1815; ≥85 years, n=135). Other baseline characteristics were balanced. The incidence of ILD (all grades) was 4.2% (<75 years), 5.1% (75-84 years), and 3.4% (≥85 years). The mortality rate due to ILD was ≤1.7% in all age groups. Other toxicities (including rash) were similar between age groups. The median PFS was 65 days (95% confidence interval [CI], 62-68) for patients aged <75 years, 74 days (95% CI, 69-82) for patients aged 75-84 years, and 72 days (95% CI, 56-93) for patients aged ≥85 years. CONCLUSIONS Efficacy and tolerability of erlotinib for elderly patients was not numerically inferior to that reported in younger patients. Erlotinib could be considered for elderly patients with recurrent/advanced NSCLC.

Phase II study of S-1 monotherapy in platinum-refractory, advanced non-small cell lung cancer

OBJECTIVE The aim of this study was to evaluate the efficacy and toxicity of a novel oral 5-fluorouracil formulation (S-1) as second-line therapy after platinum agent chemotherapy for advanced non-small cell lung cancer (NSCLC). METHODS S-1 was administered orally at a dose of 80 mg/m(2) for 28 days, followed by 14 days of rest (1 cycle); treatment was repeated until disease progression, unacceptable toxicity, or patient refusal. RESULTS Of the 46 patients enrolled in this study, 44 were evaluable. Six patients (14%) exhibited a partial response and 28 (64%) showed stable disease. Disease-control rate was 77.3% (34/44) (95% CI, 64.9-89.7%). The overall response rate was 14% (6/44) (95% CI, 3.5-23.8%). Median progression-free survival was 4.2 months. The median survival time was 16.4 months, and the one-year survival rate 60.3%. Grade 3/4 hematological toxicities were minor. All of those adverse reactions were tolerable and reversible. CONCLUSION This study demonstrated the efficacy of S-1 monotherapy as second-line treatment for advanced NSCLC.

Phase II study of pemetrexed plus intermittent erlotinib combination therapy for pretreated advanced non-squamous non-small cell lung cancer with documentation of epidermal growth factor receptor mutation status

INTRODUCTION Erlotinib and pemetrexed have been approved for the second-line and maintenance treatment of non-small cell lung cancer (NSCLC). With the recommended doses determined by our previous phase I study, we conducted a phase II study to evaluate the efficacy and safety of combination of the two agents in pretreated non-squamous NSCLC patients. METHODS This study was performed in patients with stage IIIB/IV or post-surgically recurrent non-squamous NSCLC whose disease had progressed on or after receiving first-line chemotherapy. Patients received 500 mg/m(2) of intravenous pemetrexed every 21 days and 150 mg of oral erlotinib on days 2-16 until disease progression, unacceptable toxicity, or withdrawal of consent. The expected response rate and threshold were defined as 33.5% and 10%, respectively. Assuming a one-sided alpha of 5%, a power of 80%, the possible deviation from assessment, 26 patients were necessary. RESULTS A total of 27 patients, 16 males and 11 females were recruited. Patients had the median age of 70 years (range, 48-80 years) and included 21 stage IV diseases, 22 adenocarcinomas. Epidermal growth factor receptor (EGFR) mutations were examined in all patients. One patient had positive EGFR mutation, but the other 26 patients had wild-type EGFR. The median number of treatment courses was 3 (range, 1 to over 19). The best overall response rate and disease control rate were 11.1% and 63.0%, respectively. The median progression-free survival and overall survival were 2.8 months (95% confidence interval (CI); 1.9-7.5 months) and 15.8 months (95% CI; 9.3 months to not available), respectively. Dermal, hepatic, gastrointestinal and hematological disorders were the frequently observed adverse events. One patient experienced grade 3 drug-induced interstitial lung disease. CONCLUSIONS We could not demonstrate the add-on effect of intermittent erlotinib on pemetrexed in a second-line setting for patients with non-squamous NSCLC without EGFR mutations.

Combination chemotherapy with intermittent erlotinib and pemetrexed for pretreated patients with advanced non-small cell lung cancer: a phase I dose-finding study

BackgroundErlotinib and pemetrexed have been approved for the second-line treatment of non-small cell lung cancer (NSCLC). These two agents have different mechanisms of action. Combined treatment with erlotinib and pemetrexed could potentially augment the antitumor activity of either agent alone. In the present study, we investigated the safety profile of combined administration of the two agents in pretreated NSCLC patients.MethodsA phase I dose-finding study (Trial registration: UMIN000002900) was performed in patients with stage III/IV nonsquamous NSCLC whose disease had progressed on or after receiving first-line chemotherapy. Patients received 500 mg/m2 of pemetrexed intravenously every 21 days and erlotinib (100 mg at Level 1 and 150 mg at Level 2) orally on days 2–16.ResultsTwelve patients, nine males and three females, were recruited. Patient characteristics included a median age of 66 years (range, 48–78 years), stage IV disease (nine cases), adenocarcinoma (seven cases) and activating mutation-positives in the epidermal growth factor receptor gene (two cases). Treatment was well-tolerated, and the recommended dose of erlotinib was fixed at 150 mg. Dose-limiting toxicities were experienced in three patients and included: grade 3 elevation of serum alanine aminotransferase, repetitive grade 4 neutropenia that required reduction of the second dose of pemetrexed and grade 3 diarrhea. No patient experienced drug-induced interstitial lung disease. Three patients achieved a partial response and stable disease was maintained in five patients.ConclusionsCombination chemotherapy of intermittent erlotinib with pemetrexed was well-tolerated, with promising efficacy against pretreated advanced nonsquamous NSCLC.

A Phase II Study Directed by a Clinical Pathway for Carboplatin and Weekly Paclitaxel in Previously Untreated Patients with Unresectable Non-Small Cell Lung Cancer

The objective of this phase II study was to evaluate the efficacy and safety of carboplatin and weekly paclitaxel in previously untreated patients with unresectable non-small cell lung cancer. In addition, the clinical pathway intensified the management of chemotherapy including the assessment of efficacy, safety and implementation of treatment and patient education. Patients received paclitaxel at a dose of 70 mg/m2 on days 1, 8 and 15 and carboplatin (area under the curve of 6) on day 1 and every 28th day thereafter. Fifty-eight patients were enrolled. A median of 3 cycles (range 1–6) were administered. Twenty-eight cases showed objective responses (48.2%), including 2 complete (3.4%) and 26 partial responses (44.8%; 95% confidence interval 35.4–61.1). The median survival time was 663 days, and the 1-year survival rate was 59.9%. Nineteen patients (32.8%) had grade 3, and 4 patients (6.9%) had grade 4 neutropenia. Nine patients (15.5%) experienced ≧3 grade nonhematological toxicities. There were no treatment-related deaths due to this study. Carboplatin and weekly paclitaxel combination chemotherapy might be an alternative treatment selection in patients with unresectable non-small cell lung cancer.

Augmentative effect of Nocardia rubra cell-wall skeleton (N-CWS) on lymphokine-activated killer (LAK) cell induction

SummaryThe present study elucidated that N-CWS augments the cytolytic activity against 3LL tumor cells of LAK cells from N-CWS-immunized mice administered i.p. with rIL-2. This augmentative effect of N-CWS was not seen when the LAK cells were prepared from normal mice. The cytolytic activity was predominantly expressed in the NAPC prepared from the site of injection of rIL-2, and repeated administrations of rIL-2 were required to induce and maintain this potent cytolytic activity in vivo. Serological analysis revealed that the LAK cells were positive for Thy 1.2 and asialo GM1 antigens and that they were not classical CTL or NK cells. The administration of rIL-2 statistically prolonged the MST of mice bearing LAK-sensitive 3LL cells but not the MST of mice bearing LAK-resistant EL-4 leukemia. Furthermore, combination therapy with N-CWS and rIL-2 prolonged the MST of the mice more than the therapy with rIL-2 alone. These results suggest that LAK cells potentiated with N-CWS would be useful for immunotherapy of malignant neoplasms.

Influence of indacaterol on daily physical activity in patients with untreated chronic obstructive pulmonary disease

Background Indacaterol, a once-daily, long-acting β2-agonist, may improve not only respiratory function, dyspnea symptoms, and quality of life, but also physical activity for patients with chronic obstructive pulmonary disease (COPD). This study aimed to evaluate the effect of 12-week indacaterol therapy on daytime physical activity in patients with untreated COPD. Methods The subjects were stable and untreated COPD outpatients with a percent predicted forced expiratory volume in 1 second (%FEV1) below 80%. Baseline assessments included clinical assessment, respiratory function testing, arterial blood gas analysis, the COPD assessment test (CAT™), and the Medical Outcomes Study 36-Item Short-Form Health Survey, Japanese version 2 (SF-36v2®). Patients underwent monitoring by uniaxial accelerometer before and after 12 weeks once-daily inhalation of indacaterol 150 μg/day. Results Eighteen patients were evaluable. Patient characteristics included a mean age of 74.2 years, and three patients were current smokers. Indacaterol improved mean (± standard deviation [SD]) %FEV1 from 55.2% (±17.9%) to 61.0% (±17.3%) (P=0.003), CAT scores from 16.4 (±10.2) points to 12.4 (±8.2) points (P=0.04), some scales of the SF-36v2 (physical component summary, 41.6±9.7 points to 45.1±7.9 points, P=0.03), and number of daily steps (3,311.5±2,103.3 steps/day to 3,841.8±2,096.8 steps/day, P=0.02), but did not affect daily energy expenditure (85.0±77.2 kcal change to 90.9±56.8 kcal, P=0.29) or exercise duration of an intensity of level 1 or more (36.4±23.9 minutes increase to 40.8±21.6 minutes, P=0.12). Conclusion Twelve weeks of indacaterol improved respiratory function and quality of life, but did not significantly affect physical activity in patients with moderate-to-severe COPD.