Phase I clinical and pharmacokinetic study of oxaliplatin, irinotecan and capecitabine

A Phase I Study of Irinotecan, Capecitabine (Xeloda), and Oxaliplatin in Patients With Advanced Colorectal Cancer

BACKGROUND

The objective of the present phase I study was to define the dose-limiting toxicities (DLTs) and maximum tolerated dose (MTD) of irinotecan, capecitabine, and oxaliplatin given in combination (IXO regimen) to patients with previously untreated, unresectable advanced or metastatic colorectal cancer (CRC).

PATIENTS AND METHODS

Patients received oxaliplatin followed by irinotecan as intravenous infusions on day 1, with oral capecitabine taken twice daily (BID) on days 2 to 15 of a 3-week cycle. The dose ranges were explored as follows: oxaliplatin, 75 to 120 mg/m²; irinotecan, 160 to 230 mg/m²; capecitabine, 750 to 1000 mg/m² BID. Dose escalation was performed individually for each drug at each dose level according to the type and severity of toxicity encountered in the previous cohort.

RESULTS

A total of 39 patients were enrolled at 7 dose levels and the MTD. The recommended doses for phase II evaluation were oxaliplatin 100 mg/m², irinotecan 160 mg/m², and capecitabine 950 mg/m² BID. Diarrhea and febrile neutropenia were DLTs. Of the 39 enrolled patients, 26 (67%) had confirmed objective responses. The median progression-free survival was 11 months, and the median overall survival was 25 months. The survival rate at 5 years was 23%.

CONCLUSION

The IXO regimen has a manageable toxicity profile with promising antitumor activity as first-line treatment of advanced and metastatic CRC.

Phase I Clinical Trials in Patients ≥80

Phase I clinical trials play a crucial role in development of therapeutics for cancer patients. During phase I clinical trials common toxicities are delineated, dose limiting toxicities (DLT) are determined and a dose for phase II studies is recommended. However, reviews of the phase I population indicate a younger group of participants with a median age of 50-55. No data exists on the performance of octogenarians on phase I trials. Concerns for enrollment of this patient population, relates to presence of comorbidities and possibly altered pharmacokinetics in the setting of unknown potential toxicities. We present herein the largest review of octogenarians on phase I trials. Twenty-two octogenarian patients with a median age of 83 were enrolled on phase I clinical trials. More than 50% of them were chemotherapy-naïve most likely indicative of the fact that treating physicians believed standard therapy to be potentially toxic to this population. These 22 patients were otherwise matched in terms of performance status and other parameters to a control group of participants < 80. This includes a similar number of cycles administered. Patients ≥80 had a 3 fold higher rate of achieving DLT (p=0.06) compared to the control group enrolled at the same dose level. The toxicities observed include cardiovascular, gastrointestinal and infectious complications. Three patients were enrolled on molecular targeted treatments with no significant toxicities. We conclude that enrollment of patients ≥80 on phase I trials of chemotherapy agents is most likely associated with higher risk of DLT.

A Phase Ib pharmacokinetic study of the anti-angiogenic agent CKD-732 used in combination with capecitabine and oxaliplatin (XELOX) in metastatic colorectal cancer patients who progressed on irinotecan-based chemotherapy

BACKGROUND

We conducted a Phase I clinical trial to evaluate the safety, tolerability, and pharmacokinetics (PK) of CKD-732 [6-O-(4-dimethylaminoethoxy) cinnamoyl fumagillol hemioxalate] in combination with capecitabine and oxaliplatin (XELOX) in nine metastatic colorectal cancer patients who had progressed on irinotecan-based chemotherapy.

METHODS

Using a dose-escalation schedule, CKD-732 doses of 2, 5, or 10 mg/m(2)/d were administered twice weekly for 2 weeks, followed by a 1-week rest. Oxaliplatin (130 mg/m(2)) was administered on day 1, and capecitabine (1,000 mg/m(2) twice a day) was orally administered for 14 days of a 3-week cycle.

RESULTS

In the group given the 10 mg/m(2)/d dose, two patients experienced dose limiting toxicities (one had grade 3 nausea, insomnia, and fatigue; the other had grade 3 insomnia). The maximum tolerated dose was 10 mg/m(2)/d, and the clinically recommended dose was 5 mg/m(2)/d for CKD-732 in combination with XELOX. Frequently encountered non-hematological grade 3/4 adverse events included insomnia (22.2%), fatigue (11.1%), sensory neuropathy (11.1%), hyperbilirubinemia (11.1%), and dyspnea (11.1%). The area under the concentration-time curve and maximum concentration of CKD-732 increased in a dose-dependent manner. There were no notable effects of CKD-732 on the PK of capecitabine and oxaliplatin-derived platinum.

CONCLUSION

The Phase II recommended dose of CKD-732 was determined to be 5 mg/m(2)/d, and this dose was safely combined with a conventional dose of capecitabine and oxaliplatin in this patient population. Further studies on the effects of CKD-732 in combination with XELOX and other chemotherapies using a larger study population are warranted.

A multi-center phase II study of oxaliplatin, irinotecan, and capecitabine in advanced gastric/gastroesophageal junction carcinoma

BACKGROUND

There is no standard first-line therapy for advanced gastric and gastroesophageal junction (GEJ) adenocarcinoma and the prognosis remains poor. Our institution conducted a phase I study of oxaliplatin, irinotecan, and capecitabine given in a novel, weekly schedule. The regimen was tolerated; pharmacodynamic studies revealed no drug interactions, and there was one confirmed response in a gastric cancer patient. We performed a phase II trial in advanced gastric and GEJ adenocarcinoma to determine response rate and response duration.

METHODS

This was a multi-center single treatment arm study involving six sites. Only prior adjuvant therapy was allowed. Patients had ECOG performance status of 0-2, adequate organ function, and were able to tolerate oral medications. All patients received oxaliplatin 60 mg/m(2) intravenously (IV) and irinotecan 50 mg/m(2) IV weekly times 4 weeks with a 2-week rest period. Capecitabine 450 mg bid orally was received on days 1 through 5 every week for 4 weeks, followed by a 2-week rest. Patients were assessed for response after the first two cycles; response duration, overall survival, and adverse events were also recorded. We estimated an improvement in historical response rate by 30% would have clinical meaning.

RESULTS

A total of 39 patients were accrued and all were assessed for toxicity; 30 patients were evaluable for response. The median age was 57.8 years (31-79 years) and 74% were male. Two patients had a complete response, with nine patients achieving a partial response. The total response rate was 28%, with nine patients not evaluable for response. The median response duration was noted at 5.97 months and median overall survival was 8.98 months. There were no grade 5 treatment related events, with all deaths secondary to disease progression. Only five grade 4 events occurred (neutropenia, hyperkalemia, hypokalemia (2), thrombosis/embolism) without grade 4 diarrhea or sensory neuropathy.

CONCLUSIONS

Oxaliplatin, irinotecan, and capecitabine given in a novel, weekly schedule does induce responses in advanced gastric and GEJ adenocarcinoma. However, the total response rate is modest and not an improvement over other regimens.