Primary prophylaxis with 3 weekly pegfilgrastim and ciprofloxacin effectively prevent (febrile) neutropenia and infection during neoadjuvant chemotherapy with docetaxel/doxorubicin/cyclophosphamide (TAC) in breast cancer patients

8008 Background: Neutropenia and infections are frequently related with the administration of TAC (docetaxel 75mg/m2, doxorubicin 50 mg/m2, cyclophosphamide 500 mg/m2 day 1, q21). We assessed in three prospective consecutive cohorts (N=949 patients) if the frequencies of (febrile) neutropenia and infections could be reduced using a primary prophylaxis with pegfilgrastim (+/- ciprofloxacin) compared to filgrastim. Methods: The GEPARTRIO-study, a phase III trial on the use of 6 to 8 cycles of TAC as neoadjuvant treatment in T2-T4 stage primary breast cancer has started using a primary prophylaxis with filgrastim given s.c. on day 3–12 every cycle in 390 patients (2401 cycles) (cohort A), pegfilgrastim given s.c. only on day 2 after amendment 1 in 323 patients (1956 cycles) (cohort B) and pegfilgrastim together with ciprofloxacin 500 mg bid on days 5–14 after amendment 2 in 236 patients (1111 cycles) (cohort C). Results: Neutropenia (maximum toxicity per patients) all grades (grades III/IV) was observed in 81.9 (65.6)% (A), 63.7 (45.0)% (B) and 59.6(42.2)% (C) (p<0.001, A vs B+C, Chi2-test). Febrile neutropenia was reported in 17.1% (A) 6.4% (B) and 4.3% (C) (p<0.001, A vs B vs C). Fever without neutropenia was observed in 16.7% (A), 15.1% (B) and 8.9% (C) (p<0.01, A+B vs C). Infections (all grades) were diagnosed in 31.2% (A), 27.8% (B) and 23.0% (C) (p<0.05, A+B vs C). Conclusions: (Febrile)neutropenia and infections during neoadjuvant chemotherapy with TAC can most effectively be avoided by primary prophylaxis with pegfilgrastim in combination with ciprofloxacin. Author Disclosure Employment or Leadership Consultant or Advisory Role Stock Ownership Honoraria Research Funding Expert Testimony Other Remuneration Amgen