Phase I trial of biweekly S-1, leucovorin, oxaliplatin, and gemcitabine (the SLOG regimen) in metastatic pancreatic adenocarcinoma (mPDAC).

369 Background: Gemcitabine and S-1 had been approved as the frontline treatment for mPDAC in Taiwan and Japan. Our previous study showed biweekly gemcitabine plus modified FOLFOX4 (the GOFL regimen) was a moderate active and well-tolerated regimen in mPDAC. To explore whether oral S-1/LV can be a substitute for infusion 5-FU/LV in combination with gemcitabine and oxaliplatin as “the SLOG regimen” to improve treatment efficacy and convenience. To define the dose-limiting toxicity (DLT), maximum tolerated dose (MTD) and preliminary anti-tumor efficacy of SLOG in patients with chemo-naïve mPDAC. Methods: Enrolled patients would receive intravenous infusion of 800 mg/m2 gemcitabine (fixed-dose rate infusion, 10 mg/m2/min) followed by 85mg/m2 oxaliplatin (2 hours) on D1 and escalating dose of oral S-1 and 20 mg/m2 leucovorin, twice daily D1-D7, every 14 days. DLTs were evaluated during the first 2 cycles of treatment. The treatment was continued until disease progression, unacceptable toxicity or withdrawal of informed consent. Results: 19 patients were enrolled into four dose levels of S-1, 20 mg/m2 (three), 30 mg/m2 (seven), 35 mg/m2 (six) and 40 mg/m2 (three). At 30 mg/m2 dose level, one patient who withdrew consent after one cycle treatment was replaced with another one. DLTs were observed in three patients, one at 30 mg/m2 (grade 3 diarrhea) and two at 40 mg/m2 (grade 3 hypersensitivity reaction and diarrhea in one each). MTD of S-1 was determined as 35 mg/m2. The median treatment duration was 8 cycles (ranged, 1-26). Of the 16 evaluable patients, the objective response rate and disease control rate were 37.5% (6 partial response, PR) and 81.3% (6 PR + 7 stable disease, SD), respectively. The median progression-free survival (PFS) was 4.6 months. At MTD dose level, there were 4 PR and 2 SD, with 6.7 months of PFS. The most common grade 3-4 adverse events included neutropenia (26.4%), diarrhea (15.8%), ALT increased (10.5%) and anemia (10.5%). Conclusions: The MTD of S-1 was 35 mg/m2 in the SLOG regimen. Extension phase II study in mPDAC is ongoing. Clinical trial information: NCT 01415713.

A phase II study of biweekly gemcitabine at fixed dose rate infusion plus S1 as first-line chemotherapy in patients with locally advanced or metastatic pancreatic cancer.

357 Background: The combination regimen of gemcitabine plus S1 (GS) as first-line chemotherapy has shown good efficacy in advanced pancreatic cancer. However, it is inconvenient to deliver gemcitabine on days 1 and 8 within one treatment cycle. In addition, previous studies have demonstrated that the gemcitabine administration by fixed dose rate infusion of 10 mg/m2/min should maximize the rate of intracellular accumulation of gemcitabine triphosphate and might improve clinical efficacy. The aim of this study was to evaluate the efficacy and safety of biweekly gemcitabine at fixed dose rate infusion combined with S1 (FGS) in chemonaive patients with locally advanced or metastatic pancreatic cancer. Methods: Forty-three eligible patients with locally advanced or metastatic pancreatic cancer received gemcitabine at a fixed dose of 10 mg/m2/min intravenously over a 2-h period on day 1, together with oral S1 40mg/m2twice daily on days 1 to 10, every 2 weeks. Tumor assessment was performed for every 3 cycles of chemotherapy. Results: All patients were evaluable for toxicity and 42 patients for efficacy. The overall response rate was 35.7% with 1 complete response, 14 partial responses, 17 stable diseases, and 10 progressions. Median time to progression was 5.9 months and median overall survival was 9.6 months. The main grade 3/4 toxicities included neutropenia (30.2%), thrombocytopenia (6.9%), anemia (2.3%), nausea (4.6%), diarrhea (2.3%). Conclusions: The biweekly FGS regimen is active, well tolerated and conveniently delivered as first-line chemotherapy for patients with locally advanced or metastatic pancreatic cancer.

Pegylated Liposomal Doxorubicin and Gemcitabine in a Fixed Dose Rate Infusion for the Treatment of Patients With Poor Prognosis of Recurrent Ovarian Cancer: A Phase Ib Study

IntroductionPegylated liposomal doxorubicin (PLD) is currently the reference treatment for platinum-resistant ovarian cancer. The combination of PLD and gemcitabine and the administration of gemcitabine at a fixed dose rate infusion (FDRI) seem to have additive activity in this disease setting. We have launched a phase Ib study with the combination of FDRI gemcitabine followed by PLD in recurrent ovarian cancer with a platinum-free interval of less than 1 year, with parallel pharmacokinetic and pharmacogenetic studies.MethodsThe starting dose of gemcitabine was 1500 mg/m2, 10 mg/m2per minute, every 2 weeks (±250 mg gemcitabine titration depending on toxicity), followed by PLD 35 mg/m2every 4 weeks. Gemcitabine pharmacokinetics and equilibrative nucleoside transporter 1, deoxycytidine kinase, and ribonucleotide reductase M1 gene expression levels were studied.ResultsThirty-five patients were treated at 3 different dose levels (DL). Dose level 1 was not tolerated. Nonfrail patients continued to be treated at DL-1 (G 1250 mg/m2on day 1 and PLD 35 mg/m2on days 1 and 15). Of 10 evaluable nonfrail patients, 4 displayed dose-limiting toxicity. Frail patients were treated at DL-2 (G 1250 mg/m2on day 1 and PLD 35 mg/m2on days 1 and 15). Of the 12 evaluable frail patients, 3 developed dose-limiting toxicity. Neutropenia, palmar-plantar erythrodysesthesia and stomatitis were the most common toxicities. The response rate was 42.8% (95% confidence interval [CI], 34.5%-51.1%), with 17.1% (6/35) complete responses and 25.7% (9/35) partial responses. The median progression-free survival was 7.7 months (95% CI, 2.2-13.1). The median overall survival was 13.9 months (95% CI, 9.4-18.4). The administration of PLD after gemcitabine did not influence gemcitabine pharmacokinetics or its metabolites. The addition of PLD to gemcitabine caused a larger and longer induction of the ribonucleotide reductase M1 gene. Patients with higher baseline levels of deoxycytidine kinase had longer progression-free survival.ConclusionThe recommended dose for a phase II study of patients with recurrent ovarian cancer having poor prognosis is PLD, 35 mg/m2on day 1, and gemcitabine, 1000 mg/m2on days 1 and 15 delivered at an FDRI of 10 mg/m2per minute in 28-day cycles.

Gemcitabine (G) fixed-dose-rate infusion (FDR) plus erlotinib (E) in patients with advanced pancreatic cancer (APC).

304 Background: G (30-minute infusion) plus E improves survival in patients with APC compared with G alone. In a recent phase III trial, G-FDR showed a trend to better OS compared with standard G (6.2 vs. 4.9 months, HR 0.83, p=0.04), although the study was underpowered to detect great difference in OS. Based on our previous experience with G-FDR, we decided to evaluate the combination of G-FDR plus E, after E approval for APC. Methods: Patients with previously untreated pathologically confirmed APC, locally advanced (LAPC) or metastatic (MPC), and ECOG PS 0-2 were included. G 1500 mg/m2 was given by 150-min infusion (10 mg/m2/min) on days 1, 8, and 15 every 28 days combined with E 100 mg/day orally. Treatment modifications for G-FDR were planned according with previously Tempero's phase II trial, and as described in prescribing information for E. Results: 62 pts were included (36M/26F), with a median age of 63 y-o (range 37-78). ECOG PS 0/1/2: 19/40/3. LAPC/MPC: 16/46. All except one had measurable disease. ORR was 13% (8 PR), 95% CI: 4.7-21.3, and there were 34 (55%) SD. Mean relative dose intensity for G was 0.76 and 0.90 for E. Main hematologic toxicities 3/4 per pt: anaemia 12/0, thrombocytopenia 7/4, neutropenia 18/7. Acneiform rash 1/2/3 occurred in 16/16/3 pts. Other relevant adverse events were (grade 2/3/4): diarrhoea 18/3/0, mucositis 5/1/0, infection 9/8/1, thrombosis 1/4/1 and vomiting 6/4/0. There were three treatment-related deaths (septic shock, cholangitis, and bilateral pulmonary embolism). Ten pts (all LAPC) received RT after ≤ 6 cycles, all with concomitant capecitabine 825 mg/m2 bid. In 4 pts salvage surgery were performed: 2 R0, 1 R1 and 1 R2. Median PFS was 4.9 months (95% CI: 3-6.7), 7.9 m for LAPC and 2.5 m for MPC (p = 0.004). Median OS was 10 months (95% CI: 7.1-12.9), 17.5 m for LAPC and 7 m for MPC (p = 0.019). OS was significantly shorter in males (p = 0.01) and in pts taking major opioids (p = 0.027). There was a trend to better OS in pts who developed skin rash grade ≥ 2 (p = 0.078). Conclusions: In this noncomparative study, G-FDR plus E is a feasible regimen in APC with an acceptable toxicity and notable activity. G-FDR seems to increase hematologic toxicity compared with standard infusion. No significant financial relationships to disclose.