Tailored-dose chemotherapy with gemcitabine and irinotecan in patients with platinum-refractory/resistant ovarian or primary peritoneal cancer: a phase II trial

Objective: We investigated the efficacy and toxicity of tailored-dose chemotherapy with gemcitabine and irinotecan for platinum-refractory/resistant ovarian or primary peritoneal cancer.

Methods: We enrolled patients with ovarian or primary peritoneal cancer who received ≥2 previous chemotherapeutic regimens but developed progressive disease during platinum-based chemotherapy or within 6 months post-treatment. All patients received gemcitabine (500 mg/m²) and irinotecan (50 mg/m²) on days 1 and 8 every 21 days at the starting dose. The dose was increased or decreased by 4 levels in subsequent cycles based on hematological or non-hematological toxicities observed. The primary endpoint was progression-free survival (PFS), and secondary endpoints were disease control rate (DCR), overall survival (OS), and adverse events.

Results: We investigated 25 patients who received 267 cycles (median 8 cycles/patient) between October 2008 and May 2011. Tailored-dose gemcitabine was administered up to the 5th cycle as follows: 1,000 mg/m² in 1 (4%), 750 mg/m² in 16 (64%), 500 mg/m² in 6 (24%), and 250 mg/m² in 2 patients (8%). The median PFS and OS were 6.2 months (95% confidence interval [CI]=2.7-10.7) and 16.8 months (95% CI=9.4-30.7), respectively. The DCR was 76%, and PFS was >6 months in 12 of 25 patients (48%). Grade 3 hematological toxicities included leukopenia (9.4%), neutropenia (11.2%), anemia (9.8%), and thrombocytopenia (1.1%). Grade 3/4 non-hematological toxicities did not occur except for fatigue in one patient.

Conclusions: Tailored-dose chemotherapy with gemcitabine and irinotecan was effective and well tolerated in patients with platinum-refractory/resistant ovarian or primary peritoneal cancer.

Trial registration: UMIN Clinical Trials Registry Identifier: UMIN000004449.