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.

Docetaxel plus oxaliplatin with or without fluorouracil or capecitabine in metastatic or locally recurrent gastric cancer: a randomized phase II study

BACKGROUND

Docetaxel/cisplatin/infusional 5-fluorouracil (5-FU; DCF) is a standard chemotherapy regimen for patients with advanced gastric cancer (GC). This phase II study evaluated docetaxel/oxaliplatin (TE), docetaxel/oxaliplatin/5-FU (TEF), and docetaxel/oxaliplatin/capecitabine (TEX) in patients with advanced GC.

PATIENTS AND METHODS

Patients with metastatic or locally recurrent gastric adenocarcinoma (including carcinoma of the gastro-oesophageal junction) were randomly assigned (1 : 1 : 1) to TE, TEF, or TEX. Each regimen was tested at two doses before full evaluation at optimized dose levels. The primary end point was progression-free survival (PFS). Overall survival (OS), tumour response, and safety were also assessed. A therapeutic index (median PFS relative to the incidence of febrile neutropenia) was calculated for each regimen and compared with DCF (historical data).

RESULTS

Overall, 248 patients were randomly assigned to receive optimized dose treatment. Median PFS was longer with TEF (7.66 [95% confidence interval (CI): 6.97-9.40] months) versus TE (4.50 [3.68-5.32] months) and TEX (5.55 [4.30-6.37] months). Median OS was 14.59 (95% CI: 11.70-21.78) months for TEF versus 8.97 (7.79-10.87) months for TE and 11.30 (8.08-14.03) months for TEX. The rate of tumour response (complete or partial) was 46.6% (95% CI 35.9-57.5) for TEF versus 23.1% (14.3-34.0) for TE and 25.6% (16.6-36.4) for TEX. The frequency and type of adverse events (AEs) were similar across the three arms. Common grade 3/4 AEs were fatigue (21%), sensory neuropathy (14%), and diarrhoea (13%). Febrile neutropenia was reported in 2% (TEF), 14% (TE), and 9% (TEX) of patients. The therapeutic index was improved with TEF versus TEX, TE, or DCF.

CONCLUSION

These results suggest that TEF is worthy of evaluation as an arm in a phase III trial or as a backbone regimen for new targeted agents in advanced GC. CLINICALTRIALS.GOV: Identifier Trial registration number: NCT00382720.

A randomized, multicenter, phase II study of vandetanib monotherapy versus vandetanib in combination with gemcitabine versus gemcitabine plus placebo in subjects with advanced biliary tract cancer: the VanGogh study

BACKGROUND

The management of biliary tract cancers (BTCs) is complex due to limited data on the optimal therapeutic approach. This phase II multicenter study evaluated the efficacy and tolerability of vandetanib monotherapy compared with vandetanib plus gemcitabine or gemcitabine plus placebo in patients with advanced BTC.

PATIENTS AND METHODS

Patients were randomized in a 1 : 1 : 1 ratio to three treatment groups: vandetanib 300 mg monotherapy (V), vandetanib 100 mg plus gemcitabine (V/G), gemcitabine plus placebo (G/P). Vandetanib (300 mg or 100 mg) or placebo was given in single oral daily doses. Gemcitabine 1000 mg/m(2) was i.v. infused on day 1 and day 8 of each 21-day cycle. The primary end point was progression-free survival (PFS). Secondary end points were: objective response rate (ORR), disease control rate, overall survival, duration of response, performance status and safety outcomes.

RESULTS

A total of 173 patients (mean age 63.6 years) were recruited at 19 centers across Italy. Median (95% confidence intervals) PFS (days) were 105 (72-155), 114 (91-193) and 148 (71-225), respectively, for the V, V/G and G/P treatment groups, with no statistical difference among them (P = 0.18). No statistical difference between treatments was observed for secondary end points, except ORR, which slightly favored the V/G combination over other treatments. The proportion of patients reporting adverse events (AEs) was similar for the three groups (96.6% in V arm, 91.4% in the V/G arm and 89.3% in the G/P arm).

CONCLUSIONS

Vandetanib treatment did not improve PFS in patients with advanced BTC. The safety profile of vandetanib did not show any additional AEs or worsening of already known AEs.

CLINICAL TRIAL NUMBER

NCT00753675.

FOLFOXIRI in combination with panitumumab as first-line treatment in quadruple wild-type (KRAS, NRAS, HRAS, BRAF) metastatic colorectal cancer patients: a phase II trial by the Gruppo Oncologico Nord Ovest (GONO)

BACKGROUND

The FOLFOXIRI regimen developed by the Gruppo Oncologico Nord Ovest (GONO) demonstrated higher activity and efficacy compared with FOLFIRI in metastatic colorectal cancer (mCRC). Panitumumab is effective in some patients with KRAS codon 12-13 wild-type mCRC. KRAS codon 61, HRAS, NRAS, and BRAF V600E mutations might predict resistance to anti-epidermal growth factor receptor antibodies.

PATIENTS AND METHODS

We conducted a phase II study evaluating the combination of panitumumab (6 mg/kg on day 1) with a slightly modified GONO-FOLFOXIRI (irinotecan 150 mg/m², oxaliplatin 85 mg/m², and folinate 200 mg/m² on day 1, followed by fluorouracil 3000 mg/m² as a 48-h continuous infusion starting on day 1) repeated every 2 weeks as first-line treatment of wild-type KRAS, HRAS, NRAS (codon 12-13-61), and BRAF unresectable mCRC patients. Fluorouracil dose was reduced to 2400 mg/m² after two of the first three patients reported grade 3-4 diarrhoea (in one case with febrile neutropenia). Induction treatment was scheduled for a maximum of 12 cycles, followed by panitumumab ± fluorouracil/folinate maintenance until progression. Primary end point was overall response rate (ORR).

RESULTS

Eighty-seven patients were screened and 37 were enrolled. Thirty-three patients achieved an objective response (ORR: 89%; 95% CI 75% to 96%). Sixteen patients (43%) underwent secondary surgery of metastases, and R0 resection was achieved in 13 cases (35%). At a median follow-up of 17.7 months, median progression-free survival was 11.3 months (95% CI 9.7-12.9 months). After amendment, most common grade 3-4 adverse events reported during induction treatment were neutropenia (48%; febrile neutropenia: 5%), diarrhoea (35%), asthenia (27%), stomatitis (14%), and skin toxic effect (14%). One treatment-related death was registered.

CONCLUSIONS

Adding panitumumab to FOLFOXIRI is feasible decreasing the dose of fluorouracil and irinotecan to reduce the risk of diarrhoea. Activity and secondary resectability of metastases among Ras-BRAF wild-type patients are promising.