Phase I study of the IXO regimen, irinotecan (I), capecitabine (X), oxaliplatin (O), as first-line therapy for metastatic colorectal cancer: Final survival results

4082

Background: This study was designed to determine the dose-limiting toxicity (DLT), maximum tolerated dose (MTD) and efficacy of the IXO regimen when used as first-line treatment for metastatic colorectal cancer (mCRC). Methods: Patients with ECOG PS 0–2, histologically proven, chemo-naïve, non-resectable mCRC were eligible. Phase I starting doses were as follows: I (180 mg/m2 i.v.) d1, X (850 mg/m2 bid orally) d2–15, O (85 mg/m2 i.v.) d1; q3w. Dose escalation (3+3 design) was based on toxicity observed at previous dose levels (DL) until DLT and the MTD were reached. Results: 39 pts (31 male/8 female, median age 58 years, ECOG PS 0–1 in 37, 95%) received a median of 11 cycles (range 1–34) at 8 DLs. 39 pts were evaluable for toxicity. The most common grade 3/4 hematological adverse events (AEs) were granulocytopenia (60%) and fever/febrile neutropenia (18%). The most common grade 3 non-hematological AEs were diarrhea (15%), vomiting (10%), fatigue (8%). No grade 3/4 neuropathy was reported. DLTs: 1 DLT was observed at each of the first 4 DLs, no DLTs at DL5 & 6, 1 at DL7 and 2 at DL8. MTD was reached at DL8. The recommended phase II dose (DL7) is as follows: I (160 mg/m2), X (950 mg/m2), O (100 mg/m2). Efficacy: 38 pts are evaluable for efficacy. The RR is 74% (95% CI 60–89), including 4 CRs, 25 PRs and 6 SDs. The disease control rate is 90% (95% CI 80–100). 10 (26%) pts had subsequent liver surgery with curative intent; 1 had lung resection. Median progression-free survival was 12.3 months (95% CI, 8–17). Overall median survival was 26.4 months (95% CI, 13–36). Conclusions: Diarrhea is the main DLT. Severe neutropenia was of short duration and manageable. The IXO regimen is well tolerated and highly effective as first-line treatment for mCRC. It appears to be particularly effective in downsizing of initially unresectable colorectal cancer liver metastases. A phase II study to confirm the efficacy/safety of IXO in combination with bevacizumab (Avastin) is ongoing. Supported by: Hoffmann La-Roche, Sanofi-Aventis, Pfizer Canada.

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Encouraging results from a phase I study of capecitabine (X), irinotecan (I) and oxaliplatin (O) as first-line therapy in patients (pts) with metastatic colorectal cancer (MCRC)

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Background: First-line treatment with I, O and infusional 5-FU/Leucovorin (LV) triplets is associated with high response rates and long survival in MCRC. The oral fluoropyrimidine X is better tolerated and shows improved response rates vs. 5- FU/LV in MCRC. This dose-escalation study aims to establish dose-limiting toxicity (DLT), maximum tolerated dose (MTD) and recommended phase II doses (RPIID) of I, O and X and to evaluate efficacy and safety in first-line. Methods: Starting doses were: I (180mg/m2 i.v. d1), O (85mg/m2 i.v. d1), × (850mg/m2 bid orally d2–15). Dose escalations are based on toxicity observed at previous dose level (DL), until DLT, MTD and RPIID are reached. Results: We have enrolled 27 pts (21 men, 6 women), median age 59 years (range 25–74), at 6 DLs. ECOG PS was 0 or 1 in 25 pts, and 2 in 2 pts. Pts received a median of 10 cycles (range 1–23). All pts are evaluable for toxicity (24 for efficacy). Most common grade 3/4 hematological adverse events (AEs) during dose escalation: granulocytopenia (41%), anemia (7%), and thrombocytopenia (15%). Most common grade 3 non-hematological AEs: late-onset diarrhea (11%), fever (14%), and fatigue (4%). DLTs at each dose level: DL1 (1 febrile neutropenia with bowel perforation); DL2 (1 grade 3 diarrhea); DL3 (1 febrile neutropenia with grade 2 edema); DL4 (1 severe febrile neutropenia in cycles 2&3, pt deceased due to sepsis); no DLTs were reported at DL5 & 6. MTD has not yet been reached. Overall response rate is 79% (95% CI, 62–97%), including 2 CRs and 17 PRs (3 still unconfirmed). Disease control rate is 92%. Two pts had subsequent curative liver resection and 4 pts are under consideration for curative procedures. Median progression-free survival is 15 months (95% CI, 8–22). Conclusions: XIO is well tolerated and highly effective as first-line treatment for MCRC. Severe neutropenia was significant but of short duration and manageable; it is likely to be the main DLT. MTD has not yet been identified but is expected shortly. A phase II study to confirm the efficacy and safety of XIO, possibly in combination with targeted agents, will follow. Supported by Roche, Sanofi-Aventis, and Pfizer Canada.

No significant financial relationships to disclose.

Phase I study of Aplidine in a dailyx5 one-hour infusion every 3 weeks in patients with solid tumors refractory to standard therapy. A National Cancer Institute of Canada Clinical Trials Group study: NCIC CTG IND 115

BACKGROUND

Aplidine is a cyclic depsipeptide isolated from the marine tunicate Aplidium albicans.

METHODS

This phase I study of Aplidine given as a 1-hour i.v. infusion daily for 5 days every 3 weeks was conducted in patients with refractory solid tumors. Objectives were to define the dose limiting toxicities, the maximal tolerated dose, and the recommended phase II dose.

RESULTS

Thirty-seven patients were accrued on study. Doses ranged from 80 microg/m(2) to 1500 microg/m(2)/day. Eleven patients received more than three cycles of Aplidine. Dose-limiting toxicities occurred at 1500 microg/m(2) and 1350 microg/m(2)/day and consisted of nausea, vomiting, myalgia, fatigue, skin rash and diarrhea. Mild to moderate muscular pain and weakness was noted in patients treated with multiple cycles with no significant drug related neurotoxicity. Bone marrow toxicity was not observed. The recommended dose for phase II studies was 1200 microg/m(2) daily for 5 days, every 3 weeks. Pharmacokinetic studies performed during the first cycle demonstrated that therapeutic plasma levels of Aplidine are reachable well below the recommended dose. Nine patients with progressive disease at study entry had stable disease and two had minor responses, one in non-small cell lung cancer and one in colorectal cancer.

CONCLUSIONS

Aplidine given at a dose of 1200 microg/m(2) daily for 5 days, every 3 weeks is well tolerated with few severe adverse events. This schedule of Aplidine is under evaluation in phase II studies in hematological malignancies and solid tumors.

A phase I/II study of capecitabine (X), irinotecan (I) and oxaliplatin (O) as first-line therapy in patients (pts) with advanced or metastatic colorectal cancer (MCRC)

13540

Background: Triplets of I, O and infusional 5-FU/Leucovorin (LV) are associated with high response rates and long survival in first-line MCRC [Falcone et al. JCO 2002;20:4006–14]. The oral fluoropyrimidine X has proved higher response rates and improved safety vs. 5-FU/LV in MCRC. Methods: This ongoing dose-escalation study aims to establish dose-limiting toxicity (DLT), maximum tolerated dose (MTD) and recommended phase II doses (RPIID) of I and O in combination with X as first-line therapy for MCRC and to assess the efficacy and safety of this XIO combination. Starting doses were: I (180mg/m2 i.v. on day 1), O (85mg/m2 i.v. on day 1), and X (850mg/m2 bid orally on days 2–15). Dose escalations are based on toxicity observed at the previous dose level (DL), until DLT, MTD and RPIID are documented, at which time a phase II component begins. Results: We enrolled 18 pts (13 men, 5 women), median age 61 (range 44–74) at 4 DLs. ECOG PS was 0 or 1 in 17 pts, and 2 in 1 pt. Pts received a median of 7 cycles (range 1–15) of XIO. All pts are evaluable for toxicity and 14 for response. The most common adverse events were: neutropenia (83% all grades (G) with 4 G3, 4 G4), diarrhea (67%, 4 G3, one of which was a DLT). Nausea (78%) and vomiting (56%) were mild and controlled with anti-emetics. Fatigue occurred in 50% pts, with 1 G3. The DLT was febrile neutropenia (3 pts at DLs 1, 3, & 4 respectively). One pt at DL4 developed severe neutropenia and sepsis during cycle 3, had aspiration pneumonia and died in hospital from respiratory and cardiac complications. MTD has not yet been reached. Responses were observed at all DLs: 11 partial responses with 2 still unconfirmed (79%, 95% CI 54–100), and 2 stable disease (14%). Progression-free survival and overall survival have not been reached. Conclusions: XIO is well tolerated and demonstrated significant efficacy as first-line treatment in MCRC. Severe neutropenia was significant but was of short duration and manageable. It is likely to be the main DLT. MTD has not yet been identified but is expected in the next few pts. A phase II study to confirm the efficacy and safety of the XIO combination will follow. Supported by Roche, Sanofi Aventis, and Pfizer Canada Inc.

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A National Cancer Institute of Canada Clinical Trials Group Study – IND.135: Phase I/II study of irinotecan (camptosar), oxaliplatin and raltitrexed (tomudex) (COT) in patients with advanced colorectal cancer

Thirty-one patients with metastatic colorectal cancer were enrolled in this phase I/II trial of a triple combination of camptosar (C), oxaliplatin (O) and tomudex (T), all given on day one of a convenient three-week schedule. Patients received 257 cycles (1-18) in five cohorts. Toxicity was manageable and haematological toxicity was mild to moderate. Diarrhoea was the main dose-limiting toxicity; nausea and vomiting were common. Fatigue was frequent, moderate in severity and a reason for discontinuation in some patients. The recommended phase II doses were (C) 220 mg/m(2), (O) 100mg/m(2), (T) 2.75 mg/m(2). A 50% response rate in 30 evaluable patients was confirmed by an independent radiology review board; progression-free survival and overall median survival were 7.3 months and 16.6 months, respectively. Of the 16 patients treated at the recommended dose, 9 (56.3%) experienced partial response. Further evaluation in a randomized study compared to sequential doublets is warranted. Triple combinations could be relevant in curative settings for high-risk patients.