M. Mabro

Can chemotherapy be discontinued in unresectable metastatic colorectal cancer? The GERCOR OPTIMOX2 Study.

PURPOSE This study compared chemotherapy discontinuation with maintenance therapy with leucovorin and fluorouracil after six cycles of folinic acid, fluorouracil, and oxaliplatin (FOLFOX) chemotherapy in the first-line treatment of metastatic colorectal cancer. PATIENTS AND METHODS Two hundred two patients with untreated metastatic colorectal cancer were randomly assigned to receive six cycles of modified FOLFOX7 (mFOLFOX7) followed by simplified leucovorin plus bolus and infusional fluorouracil until progression (arm 1 or maintenance arm, n = 98) or six cycles of mFOLFOX7 before a complete stop of chemotherapy (arm 2 or chemotherapy-free interval [CFI] arm, n = 104). Reintroduction of mFOLFOX7 was scheduled after tumor progression in both arms. The primary study end point was duration of disease control (DDC). RESULTS Median DDC was 13.1 months in patients assigned to the maintenance arm and 9.2 months in patients assigned to the CFI arm (P = .046). Median progression-free survival (PFS) and overall survival were 8.6 and 23.8 months, respectively, in the maintenance arm and 6.6 and 19.5 months, respectively, in the CFI arm. Median duration of maintenance therapy (arm 1) and CFIs (arm 2) were 4.8 months and 3.9 months, respectively. Overall response rates were 59.2% and 59.6% for the initial FOLFOX chemotherapy and 20.4% and 30.3% for FOLFOX reintroduction in arms 1 and 2, respectively. CONCLUSION The planned complete discontinuation of chemotherapy had a negative impact on DDC and PFS compared with the maintenance therapy strategy. These results suggest that chemotherapy discontinuation cannot be decided before therapy is initiated in patients with advanced colorectal cancer.

CPT-11 (Irinotecan) addition to bimonthly, high-dose leucovorin and bolus and continuous-infusion 5-fluorouracil (FOLFIRI) for pretreated metastatic colorectal cancer

CPT-11 (irinotecan) has shown activity in patients with advanced colorectal cancer resistant to leucovorin (LV) and 5-fluorouracil (5-FU). In this study, the simplified bimonthly LV-5-FU regimen was combined with CPT-11 (FOLFIRI) as third-line therapy for patients with advanced colorectal cancer. Continuous infusion of 5-FU was administered with disposable pumps as outpatient therapy. FOLFIRI consisted of CPT-11 180 mg/m2 as a 90-min infusion day 1; LV 400 mg/m2 as a 2-h infusion during CPT-11, immediately followed by 5-FU bolus 400 mg/m2 and 46-h continuous infusion of 2.4-3 g/m2 every 2 weeks. Among the 33 patients treated, 2 had partial responses for an overall response rate of 6%; 20 patients were stabilised (61%) and 11 had disease progression (33%). From the start of FOLFIRI, median progression-free survival was 18 weeks and median survival was 43 weeks. For the 242 cycles analysed, NCI-CTC toxicities grade 3-4 per patient were nausea 15%, diarrhoea 12% and neutropenia 15%. Overall, 10 patients (30%) experienced grade 3-4 toxicity. 7 patients (21%) had grade 2 alopecia. FOLFIRI generated activity and acceptable toxicity, in heavily pretreated patients, with limited diarrhoea, mostly asymptomatic neutropenia and manageable nausea and relatively uncommon alopecia. This regimen is suitable for studies in chemotherapy-naïve patients.

High-dose intensity oxaliplatin added to the simplified bimonthly leucovorin and 5-fluorouracil regimen as second-line therapy for metastatic colorectal cancer (FOLFOX 7)

This phase II study examined a regimen (FOLFOX7) of leucovorin (LV), high-dose intensity oxaliplatin, and 5-fluorouracil (5-FU), as second-line therapy for metastatic colorectal cancer. 48 patients were enrolled - 36 refractory and 12 resistant to prior therapy with LV-5-FU. Oxaliplatin (130 mg/m2) was infused with LV (400 mg/m2) over 2 h on day 1, followed by bolus 400 mg/m2 and a 46-h infusion (2400 g/m2) of 5-FU, every 2 weeks. Patients who responded or were stable received eight cycles. Patients were evaluated every 2 months. 20 patients (42%) had partial responses (95% confidence interval (CI): 28-56%), 19 (40%) had stable disease and 9 (19%) progressed. Median progression-free survival (PFS) was 6 months and median survival 16.1 months. Toxic effects of National Cancer Institute-Common Toxicity Criteria (NCI-CTC) grade 3/4 were: peripheral neuropathy 15%, nausea 8%, diarrhoea 11%, neutropenia 9%, thrombocytopenia 11%. Overall, 38% of patients experienced grade 3/4 toxicities, and 64% received 90% or more of the scheduled oxaliplatin dose intensity during the first four cycles. FOLFOX7 was highly active, with good tolerability, in pretreated patients resistant to LV-5-FU [corrected].

Evaluation of oxaliplatin dose intensity in bimonthly leucovorin and 48-hour 5-fluorouracil continuous infusion regimens (FOLFOX) in pretreated metastatic colorectal cancer

BACKGROUND Studies of bimonthly 48-hour regimens of high-dose leucovorin (LV) (FOLinic acid), 5-fluorouracil (5-FU) by continuous infusion combined with OXaliplatin (FOLFOX) in pretreated patients with metastatic colorectal cancer suggest that oxaliplatin dose intensity is an important prognostic factor for response rate and progression-free survival (PFS). To help define the optimal dose schedule for oxaliplatin in pretreated metastatic colorectal cancer, we retrospectively analyzed data from three phase II studies using different FOLFOX regimens (FOLFOX2, 3 and 6). PATIENTS AND METHODS Data on 126/161 patients were analyzed. FOLFOX2 included oxaliplatin 100 mg/m2; FOLFOX3, 85 mg/m2; and FOLFOX6, 100 mg/m2 (added to a simplified LV-5-FU regimen), all as two-hour infusions. A total of 47 patients received low dose intensity oxaliplatin (LDI: < or = 85 mg/m2/2 weeks) and 79 patients high dose intensity oxaliplatin (HDI: > 85 mg/m2/2 weeks). RESULTS Objective responses occurred in 31 (39%) HDI patients and 9 (19%) LDI patients (P = 0.03). Median PFS was 28 weeks, with 52% of HDI patients progression free at 6 months, and 26 weeks with 36% of LDI patients progression free at six months (P = 0.02). Increased oxaliplatin dose intensity was not associated with increased neurotoxicity or other toxicities. FOLFOX are among the most effective regimens for treating LV-5-FU-resistant metastatic colorectal cancer. CONCLUSIONS This study shows that oxaliplatin dose intensification significantly improves response rate and PFS in pretreated metastatic disease without increasing severe toxicity.

Panitumumab combined with irinotecan for patients with KRAS wild-type metastatic colorectal cancer refractory to standard chemotherapy: a GERCOR efficacy, tolerance, and translational molecular study

BACKGROUND The purpose of this study was to evaluate the combination of panitumumab and irinotecan in patients with KRAS wild-type metastatic colorectal cancer refractory to standard chemotherapy (oxaliplatin, fluoropyrimidines-irinotecan and bevacizumab). PATIENTS AND METHODS KRAS status was first determined locally but subsequent validation of KRAS status and additional screenings (rare KRAS, NRAS, BRAF mutations and EGFR copy number) were centrally assessed. Patients received panitumumab (6 mg/kg) and irinotecan (180 mg/m²) every 2 weeks. RESULTS Sixty-five eligible patients were analyzed. The objective response rate (ORR) was 29.2% [95% confidence interval (95% CI) 18.2-40.3]. Median progression-free and overall survivals were 5.5 and 9.7 months, respectively. Most frequent grade 3/4 toxic effects were skin 32.3%, diarrhea 15.4% and neutropenia 12.3%. Tissue samples were available for 60 patients. For the confirmed KRAS wild-type population codon 12 or 13 mutation (n = 54), ORR was 35.2% (95% CI 22.4.1-47.9). Thirteen patients had a NRAS, a BRAF or a rare KRAS mutation, and no tumor response was observed in this subgroup when compared with 46.3% (95% CI 31.1-61.6) ORR in the subgroup of 41 patients with no identified mutation. CONCLUSION Panitumumab and irinotecan is an active third-line regimen in a well-defined population based on biomarkers. CLINICALTRIALS. GOV IDENTIFIER NCT00655499.BACKGROUND The purpose of this study was to evaluate the combination of panitumumab and irinotecan in patients with KRAS wild-type metastatic colorectal cancer refractory to standard chemotherapy (oxaliplatin, fluoropyrimidines-irinotecan and bevacizumab). PATIENTS AND METHODS KRAS status was first determined locally but subsequent validation of KRAS status and additional screenings (rare KRAS, NRAS, BRAF mutations and EGFR copy number) were centrally assessed. Patients received panitumumab (6 mg/kg) and irinotecan (180 mg/m²) every 2 weeks. RESULTS Sixty-five eligible patients were analyzed. The objective response rate (ORR) was 29.2% [95% confidence interval (95% CI) 18.2-40.3]. Median progression-free and overall survivals were 5.5 and 9.7 months, respectively. Most frequent grade 3/4 toxic effects were skin 32.3%, diarrhea 15.4% and neutropenia 12.3%. Tissue samples were available for 60 patients. For the confirmed KRAS wild-type population codon 12 or 13 mutation (n = 54), ORR was 35.2% (95% CI 22.4.1-47.9). Thirteen patients had a NRAS, a BRAF or a rare KRAS mutation, and no tumor response was observed in this subgroup when compared with 46.3% (95% CI 31.1-61.6) ORR in the subgroup of 41 patients with no identified mutation. CONCLUSION Panitumumab and irinotecan is an active third-line regimen in a well-defined population based on biomarkers. ClinicalTrials.gov Identifier NCT00655499.

Bevacizumab with or without erlotinib as maintenance therapy in patients with metastatic colorectal cancer (GERCOR DREAM; OPTIMOX3): a randomised, open-label, phase 3 trial

BACKGROUND The combination of an anti-VEGF or an anti-EGFR-targeted monoclonal antibody with chemotherapy has shown clinical activity in patients with metastatic colorectal cancer. However, combining both anti-VEGF and anti-EGFR antibodies with chemotherapy in first-line treatment resulted in adverse outcomes. We assessed whether the combination of erlotinib, an EGFR tyrosine kinase inhibitor, with bevacizumab could increase the efficacy of maintenance therapy in patients with unresectable metastatic colorectal cancer. METHODS This randomised, open-label, phase 3 study was undertaken in 49 centres in France, Austria, and Canada. Eligible patients were aged 18-80 years with histologically confirmed, unresectable metastatic colorectal cancer, WHO performance status 0-2, had received no previous therapy for metastatic disease, and had adequate organ function. Patients without disease progression after bevacizumab-based induction therapy were randomly assigned (1:1) by a minimisation technique to bevacizumab (7·5 mg/kg every 3 weeks) or bevacizumab plus erlotinib (150 mg once daily) as maintenance therapy until progression. All patients were stratified by centre, baseline performance status, age, and number of metastatic sites. The primary endpoint was progression-free survival on maintenance therapy analysed by intention to treat. We report the final analysis. This trial is registered with ClinicalTrials.gov, number NCT00265824. FINDINGS Between Jan 1, 2007, and Oct 13, 2011, 700 eligible patients were enrolled; following induction treatment, patients without disease progression were randomly assigned to bevacizumab (n=228) or bevacizumab plus erlotinib (n=224). At the final analysis, median follow-up was 51·0 months (IQR 36·0-60·0) in the bevacizumab group and 48·3 months (31·5-61·0) in the bevacizumab plus erlotinib group. In the primary analysis (after 231 progression-free survival events), median progression-free survival from randomisation was 5·1 months (95% CI 4·1-5·9) in the bevacizumab plus erlotinib group compared with 6·0 months (4·6-7·9) in the bevacizumab group (stratified hazard ratio [HR] 0·79 [95% CI 0·60-1·06]; p=0·11; unstratified HR 0·76 [0·59-0·99]; p=0·043). In the final analysis, median progression-free survival from randomisation was 5·4 months (95% CI 4·3-6·2) in the bevacizumab plus erlotinib group compared with 4·9 months (4·1-5·7) in the bevacizumab group (stratified HR 0·81 [95% CI 0·66-1·01], p=0·059; unstratified HR 0·78 [0·68-0·96], p=0·019). At the final analysis, median overall survival from maintenance was 24·9 months (95% CI 21·4-28·9) in the bevacizumab plus erlotinib group and 22·1 months (19·6-26·7) in the bevacizumab group (stratified HR 0·79 [95% CI 0·63-0·99], p=0·036; unstratified HR 0·79 [0·64-0·98], p=0·035). The most frequent grade 3-4 adverse events were skin rash (47 [21%] of 220 patients in the bevacizumab plus erlotinib group vs none of 224 patients in the bevacizumab alone group), diarrhoea (21 [10%] vs two [<1%]), and asthenia (12 [5%] vs two [<1%]). INTERPRETATION Maintenance bevacizumab plus erlotinib might be a new non-chemotherapy-based maintenance option for the first-line treatment of patients with unresectable metastatic colorectal cancer after bevacizumab-based induction therapy. FUNDING GERCOR and F Hoffmann-La Roche.

A phase II study of FOLFIRI-3 (double infusion of irinotecan combined with LV5FU) after FOLFOX in advanced colorectal cancer patients

In advanced colorectal cancer previously treated with oxaliplatin, efficacy of irinotecan-based chemotherapy is poor and the best regimen is not defined. We designed FOLFIRI-3 and conducted a phase II study to establish its efficacy and safety in advanced colorectal cancer patients previously treated with FOLFOX. FOLFIRI-3 consisted of irinotecan 100 mg m−2 as a 60-min infusion on day 1, running concurrently with leucovorin 200 mg m−2 as a 2-h infusion on day 1, followed by 46-h continuous infusion of 5-fluorouracil (5FU) 2000 mg m−2, and irinotecan 100 mg m−2 repeated on day 3, at the end of the 5FU infusion, every 2 weeks. Sixty-five patients entered the study. The intent-to-treat objective response rate was 23% (95% CI 13–33%). Disease was stable in 37% of patients, progressed in 26% and was not assessable in 14%. From the start of FOLFIRI-3, median progression-free survival was 4.7 months and median survival 10.5 months. Main toxicities (% of patients) were grade 3–4 diarrhoea 23% and grade 4 neutropenia 11%. FOLFIRI-3 is a promising regimen achieving high response rate and progression-free survival in patients previously treated with FOLFOX with a moderate toxicity.

Efficacy of FOLFIRI-3 (irinotecan D1,D3 combined with LV5-FU) or other irinotecan-based regimens in oxaliplatin-pretreated metastatic colorectal cancer in the GERCOR OPTIMOX1 study

BACKGROUND Second-line irinotecan-based chemotherapy is commonly used in metastatic colorectal cancers after first-line oxaliplatin-based chemotherapy. No standard schedule of irinotecan has been established in this situation. PATIENTS AND METHODS Metastatic colorectal cancer patients included in the OPTIMOX1 phase III study received first-line oxaliplatin-based chemotherapy (FOLFOX). No second line was defined in the protocol, but data concerning second line were prospectively registered. Inclusion criterion was patients receiving an irinotecan-based second-line chemotherapy. Second-line progression-free survival (PFS) and tumor response were evaluated according to type of irinotecan-based regimen administered. RESULTS A total of 342 patients received irinotecan-based chemotherapy as second-line chemotherapy: FOLFIRI-3 [n = 109, irinotecan 100 mg/m(2) days 1 and 3 combined with leucovorin (LV) 400 mg/m(2) day 1 and 46-h continuous 5-fluorouracil (5-FU) 2000 mg/m(2)], FOLFIRI-1 (n = 112, irinotecan 180 mg/m(2) day 1 combined with LV 400 mg/m(2) day 1, 5-FU bolus 400 mg/m(2) and 46-h continuous 5-FU 2400 mg/m(2)) and other various irinotecan-based regimens (n = 121). Median second-line PFS was 3.0 months (FOLFIRI-3: 3.7 months; FOLFIRI-1: 3.0 months; other regimens: 2.3 months). In multivariate analysis, FOLFIRI-3 regimen (relative risk 0.43, 95% confidence interval 0.28-0.68, P = 0.0003) and lactate deshydrogenase level at inclusion (P = 0.0006) in OPTIMOX1 were associated with a longer second-line PFS. CONCLUSION In unselected patients pretreated with oxaliplatin, PFS in second line appeared to be improved by FOLFIRI-3 regimen.

Bevacizumab (Bev) with or without erlotinib as maintenance therapy, following induction first-line chemotherapy plus Bev, in patients (pts) with metastatic colorectal cancer (mCRC): Efficacy and safety results of the International GERCOR DREAM phase III trial.

LBA3500^ Background: Therapy targeting VEGF or EGFR demonstrated clinical activity in combination with chemotherapy (CT) in mCRC but monoclonal antibodies cannot be associated. The DREAM trial compares a maintenance therapy (MT) with bev +/- EGFR tyrosine kinase inhibitor erlotinib (E) after a first-line Bev-based induction therapy (IT) in pts with mCRC. METHODS Pts with previously untreated and unresectable mCRC were eligible. After a Bev-based IT with FOLFOX or XELOX or FOLFIRI, pts without disease progression were randomized to MT between Bev alone (Bev 7.5 mg/kg q3w; arm A) or Bev+E (B 7.5 mg/kg q3w, E 150 mg/day continuously; arm B). Pts were treated until progression or unacceptable toxicity. The primary endpoint was PFS on MT. RESULTS The study enrolled 700 pts from 01/2007 to 11/2011 in 3 countries (France, Canada, Austria). 446 (63.7%) pts were randomized for MT (arm A, N=224; arm B, N=222). Among the 446 randomized pts, IT regimen was FOLFOX-Bev in 265 pts (59.4%), XELOX-Bev in 135 pts (30.3%), and FOLFIRI-Bev in 46 pts (10.3%). Baseline characteristics of randomized pts were (arm A/B): ECOG PS 0, 60% in both arms; normal LDH level 47%/49%; normal alkaline phosphatase level 48%/50%; synchronous metastasis 83%/82%. The median no of MT cycles was 6 in both arms. With a median follow-up of 31.0 months, 327 PFS events were observed. Median MT-PFS were 4.6 m in arm A vs 5.8 m in arm B (HR 0.73 [95%CI: 0.59-0.91], P=.005). Median PFS from inclusion were 9.2 m vs 10.2 m. During MT, in arm A vs arm B, grade 3-4 diarrhea (<1% vs 9%) and grade 3 skin toxicity (0% vs 19%) were the main differences in toxicity. Severe adverse events from randomization related to B or E were 6 in arm A and 7 in arm B. Overall survival is not mature. CONCLUSIONS The addition of erlotinib to bevacizumab after induction therapy significantly improves the duration of maintenance PFS, following induction with first-line chemotherapy plus bevacizumab, in patients with unresectable metastatic colorectal cancer.

Bimonthly Leucovorin, Infusion 5-fluorouracil, Hydroxyurea, and Irinotecan (folfiri-2) for Pretreated Metastatic Colorectal Cancer

Irinotecan has shown activity in advanced colorectal cancer resistant to leucovorin and fluorouracil. Preclinical experiments on cell cultures and human tumor xenografts indicated potential synergy when combining irinotecan and fluorouracil. We designed a new regimen combining leucovorin, fluorouracil, irinotecan, and hydroxyurea (FOLFIRI-2) and conducted a phase II study to establish its efficacy and tolerance in advanced colorectal cancer refractory to fluorouracil and oxaliplatin. Treatment was repeated every 2 weeks and consisted of leucovorin 400 mg/m2 on day 1, immediately followed by 46 hours of continuous infusion of fluorouracil 2,000 mg/m2, irinotecan 180 mg/m2 on day 3, and hydroxyurea 1,500 mg the day before leucovorin, and on days 1 and 2. Treatment was continued until progression or limiting toxicity. Twenty-nine heavily pretreated patients entered the study. Five patients achieved an objective response (17%), and 12 obtained stabilization of disease or minor response (52%). Five patients failed to continue treatment (17%) because of toxicity or worsening condition. From the start of FOLFIRI-2 treatment, median progression-free survival was 4.1 months and median survival was 9.7 months. Grade III/IV National Cancer Institute–Common Toxicity Criteria toxicities were nausea 17%, diarrhea 31%, mucositis 14%, neutropenia 52%, and febrile neutropenia 14%. FOLFIRI-2 achieved a good rate of response and stabilization in heavily pretreated patients despite significant toxicity.