Background: GeparOcto compared efficacy and safety of two chemotherapy regimens in high-risk early breast cancer (BC): sequential treatment with intense dose-dense epirubicin, paclitaxel, and cyclophosphamide (iddEPC) and weekly treatment with paclitaxel plus non-pegylated liposomal doxorubicin (M, Myocetâ) with additional carboplatin (PM(Cb)) in triple-negative BC (TNBC). Patients and methods: Patients with cT1c-cT4a-d and centrally assessed human epidermal growth factor receptor (HER)2-positive BC or TNBC were eligible, irrespective of nodal status, luminal B-like tumours only if pNþ.Patients were randomised (stratified by BC subtype, Ki67, lymphocyte-predominant BC) to receive 18 weeks of E (150 mg/m 2 ) followed by P (225 mg/m 2 ) followed by C (2000 mg/m 2 ), each q2w for 3 cycles or weekly P (80 mg/m 2 ) plus M (20 mg/m 2 ) plus, in TNBC, Cb (area under curve (AUC) 1.5). HER2-positive BC patients additionally received trastuzumab (6 [loading dose 8]mg/kg q3w) and pertuzumab (420 [840]mg q3w) with all P and C cycles. Primary end-point was pathological complete response (pCR, ypT0/is ypN0), secondary endpoints included other pCR definitions, pCR in stratified subpopulations, tolerability and compliance. This trial is registered with ClinicalTrials.gov number NCT02125344. Results: 945/961 randomised patients started treatment. The median age was 48 years; 7.6% had cT3-4, 46% cNþ, 66% G3, 40% HER2-positive, 43% TNBC. pCR rate with iddEPC was 48.3%, with PM(Cb) 48.0%, respectively (PM(Cb) versus iddEPC odds ratio 0.99; 95% confidence interval 0.77e1.28, P Z 0.979) with no significant differences observed in TNBC, HER2-positive, luminal B-like subtypes. 16.4% with iddEPC and 34.1% with PM(Cb) discontinued treatment (P < 0.001), mainly due to adverse events; two patients on PM(Cb) died. Conclusions: In high-risk early BC there is no difference in pCR rates following neoadjuvant treatment with iddEPC or weekly PM(Cb), respectively. iddEPC is one of the effective dosedense regimens feasible in daily practice.