Gemcitabine/nab-paclitaxel vs gemcitabine/carboplatin for advanced urothelial carcinoma

To compare in a phase III trial the efficacy and safety of nanoparticle albumin-bound (nab)-paclitaxel plus gemcitabine (GA) with that of carboplatin plus gemcitabine (GCb) as a first-line treatment for patients with cisplatin-ineligible metastatic urothelial cancer (mUC).

Treatment-naive, cisplatin-ineligible patients with mUC were assigned randomly to either the GA (both nab-paclitaxel 125 mg/m² and gemcitabine 1000 mg/m² on Days 1 and 8, every 21 days) or GCb group (carboplatin area under the free carboplatin plasma concentration versus time curve of 4.5 on Day 1, gemcitabine 1000 mg/m² on Days 1 and 8, every 21 days). The primary endpoint was progression-free survival (PFS). Secondary endpoints included objective response rate (ORR), disease control rate (DCR), overall survival (OS), safety, and patient-reported outcomes (PROs).

The trial was terminated early because of slow accrual after 54 patients were enrolled: 26 in in the GA group and 28 in the GCb groups. The median PFS was 6.7 vs 5.9 months for the GA and GCb groups, respectively (P = 0.248). The median OS time was 12.1 vs 10.7 months for the GA and GCb groups, respectively (P = 0.837). The ORR and DCR were 40% vs 46.4% (P = 0.637) and 72% vs 68% (P = 0.188) in the GA and GCb groups, respectively. Patients treated with GA showed significantly lower incidence of Grade 3-4 thrombocytopenia and does reduction and delay. Although peripheral sensory neuropathy was higher in the GA arm, no Grade 3 neuropathy occurred. There was no difference in the PROs between the two groups.

While not powered for comparison, first-line GA showed similar efficacy and better tolerability and might be considered a rational alternative to GCb.