Carboplatin plus paclitaxel once a week versus every 3 weeks in patients with advanced ovarian cancer (MITO-7): a randomised, multicentre, open-label, phase 3 trial

Background: Carboplatin plus paclitaxel administered every 3 weeks is standard first-line chemotherapy for patients with advanced ovarian cancer. A weekly paclitaxel schedule combined with carboplatin every 3 weeks prolonged progression-free survival and overall survival in a Japanese phase 3 trial. The aim of our study was to assess whether a weekly schedule of carboplatin plus paclitaxel is more effective than the same drugs given every 3 weeks.

Methods: We did a multicentre, randomised, phase 3 study at 67 institutions in Italy and France. Women with FIGO stage IC-IV ovarian cancer, an ECOG performance status of 2 or lower, and who had never received chemotherapy were randomly allocated in a 1:1 ratio to receive either carboplatin (AUC 6 mg/mL per min) plus paclitaxel (175 mg/m(2)) every 3 weeks for six cycles or carboplatin (AUC 2 mg/mL per min) plus paclitaxel (60 mg/m(2)) every week for 18 weeks. Randomisation was done by computer-based minimisation, stratified by centre, residual disease after surgery, and ECOG performance status. The study was not blinded. Coprimary endpoints were progression-free survival and quality of life (assessed by the Functional Assessment of Cancer Therapy Ovarian Trial Outcome Index [FACT-O/TOI] score), and analysis was by modified intention to treat. This report presents the final analysis. The study is registered with ClinicalTrials.gov, number NCT00660842.

Findings: 822 patients were enrolled into the study between Nov 20, 2008, and March 1, 2012; 12 withdrew their consent immediately after randomisation and were excluded, and 810 were eligible for analysis. 404 women were allocated treatment every 3 weeks and 406 were assigned to the weekly schedule. After median follow-up of 22·3 months (IQR 16·2-30·9), 449 progression-free survival events were recorded. Median progression-free survival was 17·3 months (95% CI 15·2-20·2) in patients assigned to treatment every 3 weeks, versus 18·3 months (16·8-20·9) in women allocated to the weekly schedule (hazard ratio 0·96, 95% CI 0·80-1·16; p=0·66). FACT-O/TOI scores differed significantly between the two schedules (treatment-by-time interaction p<0·0001); with treatment every 3 weeks, FACT-O/TOI scores worsened at every cycle (weeks 1, 4, and 7), whereas for the weekly schedule, after transient worsening at week 1, FACT-O/TOI scores remained stable. Fewer patients assigned to the weekly group than those allocated treatment every 3 weeks had grade 3-4 neutropenia (167 [42%] of 399 patients vs 200 [50%] of 400 patients), febrile neutropenia (two [0·5%] vs 11 [3%]), grade 3-4 thrombocytopenia (four [1%] vs 27 [7%]), and grade 2 or worse neuropathy (24 [6%] vs 68 [17%]). Three deaths during the study were attributed to chemotherapy; two women died who were allocated treatment every 3 weeks and one death was recorded in the group assigned the weekly regimen.

Interpretation: A weekly regimen of carboplatin and paclitaxel might be a reasonable option for first-line treatment of women with advanced ovarian cancer.

Funding: None.