Objective: We conducted a phase I trial of escalating doses of weekly paclitaxel (Taxol) in combination with a fixed systemic administration of 5-fluorouracil (5-FU) in patients with advanced or metastatic gastric cancer. Methods: Patients with advanced or recurrent gastric cancer were treated with escalating doses of weekly paclitaxel as a 60 min intravenous (i.v.) infusion, along with a fixed dose of continuous 5-FU infused over 5 days. Plasma sampling was performed to characterize the pharmacokinetics and pharmacodynamics of paclitaxel. Results: Eighteen patients received combination therapy at four dose levels of weekly Taxol, ranging from 60 to 90 mg/m 2 /week. Dose-limiting toxicities >grade 3 were observed at the 90 mg/m 2 /week dose level. Toxicities included anemia, neutropenia, thrombocytopenia, nausea and alopecia. Two episodes of grade 4 neutropenia occurred in two of the three patients receiving this dose. At each dose level, pharmacological studies documented the persistence of significant serum paclitaxel levels over 24 h after drug administration. The maximum tolerated dose (MTD) for this regimen was 90 mg/m 2 /week of paclitaxel for 3 weeks plus 600 mg/m 2 /day of continuous 5-FU for 5 days. Conclusions: The combination of weekly paclitaxel and 5-FU demonstrated an acceptable toxicity profile and feasible pharmacokinetic results suggesting its practical applicability. Based on these findings, the recommended dose and schedule for phase II study of combination chemotherapy is paclitaxel 80 mg/m 2 /week · 3 over 4 weeks, and continuous 5-FU 600 mg/m 2 /day · 5 days every 4 weeks.

Background: Pertuzumab (P) improves clinical outcome when combined with docetaxel and trastuzumab (T). The efficacy of continuing multiple anti-HER2 therapy including P and/or T after initial progression is unclear. Eribulin mesylate (ERI) is able to overcome taxane (TAX) resistance advanced breast cancer (ABC). The objective of this study is to investigate the efficacy and safety of ERI plus P and T for both TAX and T pretreated HER2-positive ABC. Methods: This is a single institute, open-label, single-arm, Phase II study with pharmacokinetics (PK) of ERI (UMIN000012375). The initial dose of P is 840 mg, followed by 420 mg q3w; the initial dose of T 8 mg/kg, followed by 6 mg/kg q3w; ERI is administered at 1.4 mg on Days 1 and 8 of each cycle, q3w. Dose reductions of ERI (to 1.1 and 0.7 mg/m2) were permitted to manage any toxicity (more than grade 3). Patients (Pts) must have previous treatment with both TAX and T. The primary endpoint is assessed overall response rate (ORR). Secondary endpoints include progression-free survival (PFS), overall survival (OS), safety, and PK of ERI. Left ventricular ejection function (LVEF) was evaluated before and end of this study. Results: Thirty Pts were enrolled. Median age at baseline was 57 years. Half of Pts had endocrine positive. All Pts were treated with TAX and T. Twenty-one Pts were treated with anthracycline-based treatment (70%). Median number of previous chemotherapy was 4 (2-5). Pts had multiple metastases, 40% with bone, 36.7% with lung, 20% with liver, and 10% with brain. Pts received a median number of 8 cycles of ERI (mean dose 1.2 ± 0.19 mg/sqm), 8 cycles of both P and T. Total number of 27 Pts needed to reduce dose of ERI because of adverse events (AEs) especially grade 3 neutropenia. The ORR (CR+PR) was 34.8% (95% CI 16.4-57.3, n=23) with median PFS of 42.6 weeks (95% CI 20.3-51.9, n=30). Clinical benefit rate (CR+PR+≥6 month SD) was 60.9% (95% CI 16.4-57.3%). T-DM1 pretreated affected poor outcome than the other factors (p=0.0011). The most common grade 3/4 AEs were neutropenia in 20 Pts (66.7%) without febrile neutropenia. Grade 1/2 AEs were fatigue in 24 Pts (80%), anorexia in 23 Pts (76.7%), anemia in 22 Pts (73.3%), diarrhea in 20 Pts (66.7%), peripheral neuropathy in 16 Pts (53.3%), and hand-foot syndrome in 12 Pts (43.3%). Baseline LVEF was 67%. One Pt had asymptomatic LVEF decrease (below an absolute value of 55%). Otherwise, there was no overall decrease in mean LVEF from baseline. Nine points (pre-dose, end of infusion, 0.5, 1, 2, 4, 24, 72, and 168 h after ERI) of PK analyses were evaluated in 6 Pts, and 3 point (pre-dose, end of infusion, and 168 h after ERI) in 10 Pts. PK parameters of ERI were as follows; Maximum plasma concentration (Cmax) was 375.96 (257.6-531.8) ng/ml, terminal half-life was 36.807 (31.90-40.80) h, total clearance was 1.945 (1.15-3.15) L/h/m2. Cmax of ERI was not correlated with neutrophil count (R2=0.2338, n=16). Conclusions: The combination of ERI plus P and T was well tolerated; no new safety signals ware observed. PK parameter of ERI were as same as previous reports when combined with both P and T. ERI might be a one of strategy in combination with P plus T for TAX pretreated HER2 positive ABC. Citation Format: Araki K, Fukada I, Kobayashi K, Takahashi S, Ito Y. Eribulin should be a candidate strategy in combination with pertuzumab plus trastuzumab for taxane pretreated HER2 positive advance breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-15-11.

Background: Tumor-infiltrating lymphocytes might be a one of predictive outcome of human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (ABC) patients (pts) who treated with trastuzumab and pertuzumab (TP) plus docetaxel. Although peripheral blood-based parameter (PBBP) is reported as a prognostic indicator of patients with early breast cancers, utility of PBBP has not been studied in HER2-positive ABC. Objective:The aim of our study was to determine whether PBBP is significant for predictive efficacy in HER2-positive ABC treated with TP combined with eribulin (ERI) or nab-paclitaxel (Nab-PTX). Methods: The 51 patients' data from two single arm phase II trials was included in this retrospective-prospective study; ERI + TP (n=30) or Nab-PTX + TP (n=21) registered with UMIN000012375 or UMIN000006838, respectively. We assessed the PBBP in prospectively collected data and investigated their association with progression-free survival (PFS). In consideration of PBBP, we evaluated absolute lymphocyte count (ALC), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR). The cutoff values of ALC, NLR, and PLR were set at 1000 cells/μL, 2, and 250, respectively. Results:Median age at baseline was 58 years (range: 31-77). Median number of previous chemotherapy was 3 (range: 1-10). Pts had multiple metastases, 53% with LNs, 35% with bone, 25% with lung, 20% with liver, and 6% with brain. The objective response rate (CR+PR) and clinical benefit rate (CR+PR+ more than 6 month SD) were 37% (n=19) and 59% (n=30), respectively. The median PFS of all pts was 301 days (range: 21-1281). The PFS of pts with ALC-High was significantly better than those of ALC-low (hazard ratio (HR): 2.74, 95% confidence interval (CI): 1.28 to 5.86; p= .0097). Furthermore, improved PFS was obtained in pts with ALC greater than 1500 cells/μL compared with less than 1000 cells/uL (HR: 4.05, 95% CI: 1.60 to 11.6; p= .0029). Significant associations seem to exist irrespective of number of previous chemotherapy. Since we combined different studies for evaluating PBBP, ERI and Nab-PTX were calculated separately. Marginally significant associations between ALC and PFS were obtained both in ERI (HR: 2.18, 95% CI: 0.87 to 5.60; p=.0973) and Nab-PTX (HR: 3.26, 95% CI: 0.80 to 12.4; p=.0939). The PFS of NLR-low pts was significantly better than those of NLR-high (HR: 2.29, 95% CI: 1.01 to 5.90; p= .0477), but this statistical difference was inferior to those of ALC. There was no significant association between PLR and PFS. Conclusions: Pre-treatment ALC-High was significantly correlated with favorable PFS of pts treated with TP irrespective of combination chemotherapy in HER2-positve ABC. Prolonged PFS of TP combination therapy might be obtained mediating through host systemic onco-immunity. These data obtained here suggest that a usefulness of ALC for selecting pts who might have clinical benefit from TP combination therapy for heavily treated HER2-positve ABC. Citation Format: Araki K, Ito Y, Fukada I, Kobayashi K, Ohno S, Miyagawa Y, Imamura M, Kira A, Takatsuka Y, Egawa C, Suwa H, Miyoshi Y. Predictive impact of absolute lymphocyte counts for progression-free survival in HER2-positive advanced breast cancer treated with pertuzumab and trastuzumab plus eribulin or nab-paclitaxel [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P2-09-31.

Background: Docetaxel + Trastuzumab (H) + Pertuzumab (P) provided progression-free survival (PFS) and overall survival (OS) benefits in HER2-positive advanced or metastatic breast cancer (AMBC) in the CLEOPATRA study as a first-line therapy. However, long-term administration of docetaxel at a dose of 75 mg/m2 every 3 weeks in AMBC patients (pts) is difficult due to the toxicities. Eribulin mesylate (E) is a well-tolerated microtubule inhibitor, and we have reported the efficacy and safety of EHP regimen as first- and second-line therapy for AMBC in a multicenter, phase II study (JBCRG-M03/UMIN000012232). In this M06 study, we address the clinical question as to which is the better chemotherapy partner for HP as first line regimen, in terms of efficacy, toxicity and QOL. Methods: JBCRG-M06 is a multicenter open-label randomized phase III study for HER2-positive AMBC pts who have received no prior chemotherapy except for the HER2- Antibody-Drug Conjugate (ADC). Pts will be randomized 1:1 to E (1.4mg/m2 on day 1 and 8) + H (8 mg/kg loading dose followed by 6 mg/kg) +P (840 mg loading dose followed by 420 mg) q3wks or standard taxanes (docetaxel 75mg/m2 on day1 or paclitaxel 80mg/m2 on day 1, 8 and 15) + HP q3wks. Stratification factors for randomization are; presence of visceral metastases, number of prior taxanes on perioperative adjuvant treatment, and treatment with prior anti-HER2-ADC. Primary endpoint is PFS and secondary endpoints include overall response rate, duration of response, OS, patient-reported outcomes (PRO) relating to QOL and peripheral neuropathy, new-metastases free survival, and safety. Translational research to search for biomarker for individual precision therapy will be performed. Main eligibility criteria are as follows: pts with HER2-positive AMBC, female aged 20-70 years old, ECOG PS of 0-1, LVEF ≥ 50% at baseline and adequate organ function. Pts who had progressive MBC within 6 months after the end of primary adjuvant systemic chemotherapy are excluded. The sample size was calculated by type1 error (2-sided) of 0.05 and 80% power to estimate the noninferiority margin 1.33 with an expected median PFS of 14.2 months. The target number of pts is 480 recruited over the duration of 3-years. The first patient in was achieved on August 2017. (ClinicalTrials.gov Identifier:NCT03264547). Citation Format: Masuda N, Yamashita T, Saji S, Araki K, Ito Y, Takano T, Takahashi M, Tsurutani J, Koizumi K, Kitada M, Kojima Y, Sagara Y, Tada H, Iwasa T, Kadoya T, Iwatani T, Hasegawa H, Morita S, Ohno S. A phase III trial to compare eribulin mesylate + trastuzumab (H) + pertuzumab (P) with paclitaxel or docetaxel + HP for HER2-positive advanced or metastatic breast cancer (JBCRG-M06/ EMERALD) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-07-05.

Background: Taselisib (GDC-0032) is an orally bioavailable, potent and selective phosphoinositide 3-kinase (PI3K) inhibitor. Preclinical data showed that taselisib had increased antitumor activity against PIK3CA (gene encoding the PI3Kα isoform) mutant tumors. This study aimed to investigate the safety, tolerability and pharmacokinetics (PK) of taselisib as monotherapy and in combination with fulvestrant in Japanese patients (pts). Materials and methods: A 3+3 design was used. In Phase Ia, pts with advanced solid tumors received taselisib tablet monotherapy (2, 4 or 6 mg once daily [QD]), and safety and PK were evaluated. In Phase Ib, pts with hormone receptor-positive locally advanced or metastatic breast cancer received taselisib (2 or 4 mg QD) in combination with fulvestrant (500 mg at a time), and safety and PK were evaluated. Maximal administered doses of 6 mg QD as a single agent and 4 mg QD in combination with fulvestrant were based upon prior clinical trial experience with taselisib (Juric D. et al. AACR 2013, Abstract LB-64; Juric D. et al. SABCS 2013, Abstract PD1-3). Results: As of 15 Mar 2015, 9 pts (PIK3CA mutant: 2 pts) were enrolled in Phase Ia and 3 pts in Phase Ib. Phase Ia dose-escalation study has been completed and Phase Ib is ongoing. In Phase Ia, no dose-limiting toxicity (DLT) was observed at any dose level tested (maximum administered dose of 6 mg QD). Common (≥3 pts) adverse reactions (ARs) were stomatitis (4 pts), rash (3 pts) and diarrhea (3 pts); the only Grade ≥3 AR was neutropenia (1 pt). Partial response was observed in 1 pt who received taselisib 4 mg and had a PIK3CA mutant breast tumor. Stable disease was observed in 4 pts. Cmax and AUC indicated a dose-proportional PK profile of taselisib within the dose range tested. Moreover, taselisib PK in Japanese pts was consistent with the PK reported from North American and European pts (Juric D. et al. AACR 2013, Abstract LB-64). In Phase Ib, 3 pts received taselisib 2 mg in combination with fulvestrant and no DLT was observed. Preliminary ARs were similar to those with monotherapy and no Grade ≥3 AR was reported. Confirmation of tolerability of taselisib 4 mg in combination with fulvestrant is under evaluation. Conclusion: Taselisib monotherapy was well tolerated in Japanese pts up to a dose of 6 mg, which is the recommended dose in non-Japanese pts. Promising preliminary activity of monotherapy was observed in advanced solid tumors, especially in a pt with PIK3CA mutant tumor. The combination of taselisib 2 mg with fulvestrant is well tolerated. Investigation of tolerability of taselisib 4 mg in combination with fulvestrant is ongoing. Final results of this study will be presented here at the Symposium this year. Citation Format: Kobayashi T, Nakano K, Tomomatsu J, Nara E, Ito Y, Kobayashi K, Fukada I, Araki K, Shimomura A, Shimoi T, Kodaira M, Yunokawa M, Yonemori K, Shimizu C, Nakamura K, Kotani N, Inatani M, Tamura K, Takahashi S. Phase Ia/Ib study of taselisib (GDC-0032), a potent and selective phosphoinositide 3-kinase inhibitor, in Japanese patients with advanced solid tumors or hormone receptor-positive locally advanced or metastatic breast cancer (JO29196 study). [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-14-10.