FOLFOXIRI or FOLFOXIRI plus bevacizumab as first-line treatment of metastatic colorectal cancer: a propensity score-adjusted analysis from two randomized clinical trials

BACKGROUND

FOLFOXIRI plus bevacizumab is a valid option as upfront treatment for metastatic colorectal cancer (mCRC) patients. While several trials investigated the effect of combining bevacizumab with different chemotherapy regimens, including fluoropyrimidines monotherapy and oxaliplatin- or irinotecan-containing doublets, no randomized comparison assessing the impact of the addition of bevacizumab to FOLFOXIRI is available.

PATIENTS AND METHODS

A total of 122 mCRC patients received first-line FOLFOXIRI in the phase III trial by the GONO (FOLFOXIRI group) and 252 patients received first-line FOLFOXIRI plus bevacizumab in the TRIBE trial (FOLFOXIRI plus bevacizumab group). A propensity score-adjusted method was adopted to provide an estimation of the benefit from the addition of bevacizumab to FOLFOXIRI in terms of survival and activity parameters.

RESULTS

Patients in the FOLFOXIRI group had more frequently Eastern Cooperative Oncology Group performance status of one or two, high Köhne score, metachronous and liver-limited disease, had previously received adjuvant treatments and had their primary tumors resected. The median progression-free survival (PFS) was 12.3 months in the FOLFOXIRI plus bevacizumab group compared with 10.0 months in the FOLFOXIRI group {propensity score-adjusted hazard ratio (HR) 0.74 [95% confidence interval (CI) 0.59-0.94], P = 0.013}. This association was significant also in the multivariable model (P = 0.024). The median OS was 29.8 months in the FOLFOXIRI plus bevacizumab group compared with 23.6 months in the FOLFOXIRI group [propensity score-adjusted HR: 0.72 (95% CI 0.56-0.93), P = 0.014]. At the multivariable model, the addition of bevacizumab was still associated with significantly longer OS (P = 0.030). No significant differences in RECIST response rate (RR) [65.1% versus 55.7%; propensity score-adjusted odds ratio (OR): 1.29 (95% CI 0.81-2.05), P = 0.280], early RR [62.7% versus 57.8%; OR: 1.14 (95% CI 0.68-1.93), P = 0.619] and median depth of response (42.2% versus 53.8%, P = 0.259) were reported.

CONCLUSIONS

Though in the absence of a randomized comparison, the addition of bevacizumab to FOLFOXIRI provides significant benefit in PFS and OS, thus supporting the use of FOLFOXIRI plus bevacizumab as upfront treatment for mCRC patients.

TRIALS' NUMBERS

NCT01219920 and NCT00719797.

Early tumor shrinkage and depth of response predict long-term outcome in metastatic colorectal cancer patients treated with first-line chemotherapy plus bevacizumab: results from phase III TRIBE trial by the Gruppo Oncologico del Nord Ovest

BACKGROUND

Early tumor shrinkage (ETS) and depth of response (DoR) predict overall survival (OS) in first-line trials of chemotherapy ± anti-EGFR monoclonal antibodies in metastatic colorectal cancer (mCRC). These associations and the predictive accuracy of response measurements for survival parameters were investigated in the phase III TRIBE trial of FOLFOXIRI plus bevacizumab (bev) versus FOLFIRI plus bev.

PATIENTS AND METHODS

A landmark approach was adopted to define the assessable population. The distribution of RECIST response rate, ETS and DoR was compared in the two arms. Associations between response measurements and progression-free survival (PFS), post-progression survival (PPS) and OS were tested by univariate and multivariate Cox models. Prediction performance of each factor was estimated by C-index.

RESULTS

A significantly higher percentage of patients in the FOLFOXIRI plus bev arm achieved ETS ≥20%, when compared with the control arm (62.7% versus 51.9%, P = 0.025). Also the DoR was significantly higher in the triplet plus bev arm (43.4% versus 37.8%, P = 0.003). Both ETS and DoR were associated with PFS, PPS and OS at the univariate analyses and in the multivariate models stratified for other prognostic variables. Both ETS and DoR were able to predict survival as accurately as RECIST response.

CONCLUSION

FOLFOXIRI plus bev improves ETS and DoR when compared with FOLFIRI plus bev. Achieving rapid and deep tumor shrinkage consistently delays tumor progression and prolongs survival in patients treated with first-line chemotherapy plus bev. ETS is a promising and valuable end point for clinical trials' design deserving further investigation.

The triplet combination of irinotecan, oxaliplatin and 5FU/LV (FOLFOXIRI) vs the doublet of irinotecan and 5FU/LV (FOLFIRI) as first-line treatment of metastatic colorectal cancer (MCRC): Results of a randomized phase III trial by the Gruppo Oncologico Nord Ovest (G.O.N.O.)

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Background: We demonstrated interesting activity and manageable toxicities for the FOLFOXIRI regimen in phase I-II studies. Methods: The G.O.N.O. conduced a phase III study comparing FOLFIRI (CPT11 180 mg/sqm d1, l-LV 100 mg/sqm d1+d2, 5FU 400 mg/sqm bolus d1+d2, 5FU 600 mg/sqm 22-h inf. on d1+d2, arm A), to FOLFOXIRI (CPT11 165 mg/sqm d1, LOHP 85 mg/sqm d1, l-LV 200 mg/sqm d1, 5FU 3200 mg/sqm 48-h inf. starting on d1, arm B). Both treatments were repeated every 2 weeks and at progression to FOLFIRI a FOLFOX combination was recommended. Selection criteria included measurable and not resectable MCRC, age 18–75 years, no prior chemotherapy for advanced disease. Primary endpoint was response rate (RR) and planned accrual was 240 pts. Secondary endpoints were PFS, OS, post-CT R0 surgical resections, safety and QoL. Results: A total of 244 pts were randomized. Main toxicities were (arm A/arm B): grade 3–4 diarrhea 12%/20%, grade 3–4 vomiting 2%/7%, grade 3–4 stomatitis 3%/5%, grade 2–3 peripheral neurotoxicity 0%/20%, grade 4 neutropenia 11%/17%, febrile neutropenia 3%/5%. Two pts in each arm died within 60 days, but no toxic deaths occurred. Responses, assessed by investigators, were (arm A/arm B): complete 6%/8%, partial 35%/58%, stable 33%/21%, progression 24%/11%, for an overall RR of 41% vs 66%, p=0.0002. RR confirmed by an external panel was 34%/60%, p<0.0001. This increased activity allowed a radical secondary resection of mts in a greater percentage of patients in the FOLFOXIRI arm (6% vs 14%, p=0.05, among all 244 pts and 12% vs 36%, p=0.02, among 81 patients with liver mts only). At a median follow-up of 15.2 months 112 vs 104 pts have progressed and 81 vs 65 have died with a significant improvement in progression-free and overall survival in favor of the triplet (median PFS 6.9 vs 9.8 mos, HR: 0.63, p=0.0006; median S 16.7 vs 22.6, HR:0.70, p=0.032). Conclusions: The FOLFOXIRI regimen is feasible with manageable toxicities and significantly increases RR, R0 resection of mts, PFS and overall S compared to FOLFIRI. (Partially supported by Fondazione ARCO).

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Gemcitabine plus vinorelbine in stage IIIB or IV non-small cell lung cancer (NSCLC): a multicentre phase II clinical trial

A phase II study in patients with stage IIIB/IV non-small cell lung cancer (NSCLC) was carried out to evaluate the clinical activity and toxicity of the chemotherapeutic combination of gemcitabine+vinorelbine (GEM/VNR). Forty-five patients (40 male, 5 female) with a median age of 67 years (range 37-73) and a median ECOG performance status of 1 (range 0-2) were enrolled into the trial. Twenty patients had stage IIIB (two positive supraclavicular nodes and 20 cytologically positive pleural effusion), and 25 had stage IV NSCLC. GEM 1000 mg/m(2) diluted in 250 cc(3) of normal saline was administered iv on days 1, 8, and 15, while VNR was given 30 mg/m(2) on days 1 and 8 every 4 weeks. The median number of courses/patient was 4 (range 3-7). According to an intent-to-treat analysis 2 (4%) patients had a complete response and 16 (36%; 95% CL 22-52%) had a partial response for an overall response rate of 40% (95% CL 26-56%). Twelve (27%) patients had stable disease and 15 (33%) were considered as treatment failures. Median overall survival of the whole series was 8+ months with 33% of patients alive at 1 year. Toxicity was generally mild. WHO grade 3-4 neutropenia was recorded in 22% of cases, grade 1-3 liver toxicity in 6% of patients and neutropenia-unrelated fever in 9%. This multicentre phase II study suggests that the GEM/VNR combination regimen is an active and well tolerated regimen in patients with stage IIIB/IV NSCLC. Larger studies comparing cisplatin-based regimens to new schedules without cisplatin are warranted.