A randomized phase III trial comparing nanoparticle-based paclitaxel with solvent-based paclitaxel as part of neoadjuvant chemotherapy for patients with early breast cancer (GeparSepto): GBG 69.

TPS1141 Background: Anthracyclines (A) followed by taxanes (T) are standard of care for neoadjuvant therapy in breast cancer (BC). A reverse sequence of T followed by A was suggested to achieve higher pCR rates. Previous studies have shown that dual anti-HER2 blockade is superior to trastuzumab (H) alone and thus can increase the pCR rate by 20%. Nab-paclitaxel (nP) is a solvent-free formulation of P encapsulated in albumin and might also improve the pCR rate with eventually lower toxicity. Methods: The GeparSepto study (NCT01583426) will randomize 1200 patients to either nP (150 mg/m²) q1w or P (80mg/m²) q1w for 12 weeks followed by 4 cycles conventionally dosed EC (E 90mg/m², C 600 mg/m²) q3w for 4 cycles. Primary objective is to compare the pCR rate (ypT0+ ypN0). Patients with untreated, histologically confirmed cT2- cT4d BC can be included. HER2+ patients receive H (loading dose 8mg/kg; 6 mg/kg) plus pertuzumab (loading dose 840 mg; 420 mg) q3w concomitantly. Biomaterial including FFPE from core biops...