A phase II study of capecitabine, irinotecan, and bevacizumab (XELIRI-A) in patients (pts) with previously untreated metastatic colorectal cancer (mCRC)

Abstract

e15019 Background: Capecitabine (XEL), irinotecan (IRI) and bevacizumab (A) are all active agents in the treatment of mCRC. However, combining these agents has proven to be problematic due to overlapping toxicities. Optimal dosing strategies for this combination remain unclear. This study prospectively evaluated toxicity and efficacy of the XELIRI-A combination with dose modification. Methods: This was a single-institution, open-label phase II clinical trial. Eligible pts include those with previously untreated metastatic CRC, adequate organ function and ECOG performance status 0–2. IRI (200 mg / m2) and A (7.5 mg / kg) were given on day 1, and XEL (1000 mg / m2 p.o. BID) was given on days 1–14 of every 21-day cycle. The dose of XEL was reduced to 750 mg / m2 BID for pts age ≥ 65. The primary endpoint was progression-free survival (PFS). Secondary endpoints included response rate, time to progression, overall survival and toxicity. Results: 50 pts (ECOG PS 0:1 = 27:23; male:female= 34:16) were enrolled over 19 months. Median age was 58 (range: 35–72). 7 pts had prior adjuvant chemotherapy. A total of 360 cycles were administered, with a median of 6 (range: 1–16). To date, 20 confirmed PR, 3 unconfirmed PR, and 20 SD by RECIST criteria were observed (ORR= 40%, disease control rate 86%). The median PFS was 11.1 months (95% CI: 9.2 months - not reached), and the 1-year progression-free rate was 49%. 7 pts have gone on to have metastatectomy. The most frequently reported related grade 3 or 4 adverse events were neutropenia (6), hand-foot syndrome (6), and diarrhea (5). One death was seen on study, and 1 pt had treatment-emergent grade 3 hypertension. Conclusions: XELIRI-A at doses studied appears to be well- tolerated. Results are favorable compared to those from previous studies. XELIRI-A at reduced doses is safe and effective as first-line treatment for mCRC. [Table: see text]