Results of a phase II trial of cetuximab plus capecitabine/irinotecan as first-line therapy for patients with advanced and/or metastatic colorectal cancer.

BACKGROUND: XELIRI (capecitabine/irinotecan) is effective and well tolerated in metastatic colorectal cancer (mCRC). Cetuximab is active in mCRC alone or with chemotherapy. This study evaluated cetuximab plus XELIRI in first-line treatment of mCRC. PATIENTS AND METHODS: Subjects had histologically confirmed unresectable colorectal adenocarcinoma (with T4 lesions) after preoperative chemoradiation and/or metastases. Treatment was capecitabine 1700 mg/m2 (850 mg/m2 orally twice a day on days 1-14 for 3 weeks), irinotecan 200 mg/m2 intravenously (I.V.) on day 1 every 3 weeks, and weekly cetuximab (initially 400 mg/m2 I.V. [120 minutes], subsequently 250 mg/m2 [30 minutes]). RESULTS: Baseline characteristics (N = 70): 43 men (61%); median age, 61.5 years; Eastern Cooperative Oncology Group performance status 0/1 = 66%/34%; 94% adenocarcinoma. Previous therapy: surgery (91%), chemotherapy (14%), or radiation therapy (7%). Responses (patients completing > or = 2 cycles): complete response (5.7%), partial response (37.7%), stable disease (43.4%), and progressive disease (PD; 13.2%); 16 patients discontinued early (n = 4 allergic reaction, n = 2 withdrew consent, n = 2 death, and n = 8 other adverse events [AEs]). The overall per-protocol response rate was 43.4% (34% intent to treat [ITT]; disease control rate, 86.8%; 69% ITT). The median time to progression was 8.1 months (range, < 1-27.0 months), and the median time to response was 1.6 months (range, 1.1-8.4 months). The median survival was 20.5 months, and 45.7% of patients remain alive. Of the 38 deaths, 84% were because of PD. No death was treatment related. The most frequent grade 3/4 treatment-related AEs included diarrhea, neutropenia, and nausea/vomiting; 32% of patients required dose reductions. All patients are off the study primarily because of PD (34.3%) or AEs (40.0%). CONCLUSION: In summary, XELIRI plus cetuximab is a promising regimen that merits further study for first-line mCRC.

Phase I trial of PT-100 (PT-100), a cytokine-inducing small molecule, following chemotherapy for solid tumor malignancy.

PT-100 upregulates cytokine expression competitively inhibiting the dipeptidyl peptidase activity of fibroblast activation protein (FAP) and dipeptidyl peptidase IV (DPP-IV). This dose-escalation study was conducted to evaluate the safety of PT-100 in patients receiving myelosuppressive chemotherapy and to assess its effects on neutrophil recovery.PT-100 was administered orally for 7 days as a 200 microg, 400 microg, 800 microg, or 1,200 microg total daily dose (divided twice daily) to 6, 6, 17, and 5 patients, respectively. Patients received 2 cycles of chemotherapy: The first cycle served as each individual patient's control. Patients had to develop Grade 3+ neutropenia in Cycle 1 in order to receive PT-100 in Cycle 2. Most patients received PT-100 on Days 2-8 of chemotherapy in Cycle 2, except at 800 microg where an additional cohort (n = 8) was treated on a Days 5-11 schedule. Five of 7 patients receiving 800 microg on Days 2-8 experienced a >/=1-day improvement in Grade 3+ neutropenia in Cycle 2 versus Cycle 1. Overall, PT-100 was well tolerated. A reduction in chemotherapy-related nausea, vomiting, fatigue, alopecia, and diarrhea was noted in patients receiving PT-100. Edema/peripheral swelling, hypotension, hypovolemia, and dizziness were the most common nonhematologic adverse events considered related to PT-100. Two Grade 3 adverse events were considered related to PT-100: syncope (1,200 microg) and orthostatic hypotension (800 microg). A maximum tolerated dose was not reached. Given the accelerated neutrophil recovery, preclinical evidence of antitumor activity, and tolerable toxicities of PT-100, additional studies to optimize the PT-100 dosing schedule in patients receiving myelosuppressive chemotherapy are needed.

Phase I trial of an all-oral combination chemotherapy regimen: topotecan and capecitabine in solid tumor patients.

The objective of this phase I study was to investigate the safety of an all-oral combination chemotherapy regimen: topotecan and capecitabine. Topotecan was administered once a day for 5 consecutive days followed by 2 days of rest and was administered again for 5 consecutive days. The starting dose of topotecan was 0.5 mg/m2/d(-1). Capecitabine was administered concurrently at an oral dose of 1800 mg/m2/d(-1) divided twice daily for 14 concurrent consecutive days. Each cycle of treatment was 21 days. Topotecan pharmacokinetic studies were performed on day 1 of cycles 1 and 2. Nineteen patients with refractory cancer were treated. Dose-limiting toxicity (thrombocytopenia, diarrhea) was observed in 2 of 3 patients at a topotecan dose of 2.0 mg/m2/d(-1). A total of 10 patients were treated at the maximum-tolerated dose of topotecan (1.5 mg/m2/d(-1)) and only 1 treatment-related grade 3 nonhematologic toxic event was demonstrated; however, grade 3 hematologic toxicity was observed in 8 of 10 patients at the maximum-tolerated dose, although no correlated clinical sequela resulted. One patient achieved a partial response and 7 achieved stable disease for 4 months or longer. Measurement of plasma topotecan showed pharmacokinetics consistent with no alteration by capecitabine. In conclusion, we recommend further investigation of oral topotecan (1.5 mg/m2/d(-1)) on days 1 to 5 of each week for 2 weeks in combination with capecitabine (180 mg/m2 twice daily) on days 1 to 14 within a 21-day cycle.