Inclusion Criteria:

- Signed informed consent form;

- Histologically verified diagnosis of stage IIb/III/IV breast cancer;

- Age of 18-70 years inclusive;

- If the patient had received the chemotherapy for breast cancer, it should be finished
30 days before the beginning of the study;

- ECOG Performance Status of 0, 1 or 2, not increasing within during 2 weeks before
randomization;

- ANC level of 1500/μL and more at the beginning of the study

- Platelet count of 100 000/μL and more at the beginning of the study

- Hemoglobin level of 90 g/l and more

- Creatinine level <1.5 mg/dl

- Total bilirubin level <1.5 × the upper limit of normal (ULN)

- ALT and/or AST levels <2.5×ULN (5×ULN for patients with liver metastases);

- Alkaline phosphatase <5×ULN;

- Left ventricular ejection fraction >50% and more;

- If the patient had received adjuvant and/or neoadjuvant therapy, the cumulative dose
of anthracyclines should not exceed 500 mg/m2 for doxorubicin or 500 mg/m2 for
epirubicin;

- Ability of the participant to follow the protocol requirements, according to the
Investigator's opinion;

- Patients of childbearing potential must implement reliable contraceptive measures
during the study treatment, starting 4 weeks prior randomization and for 6 months
after the last administration of the study drug.

Exclusion Criteria:

- Patient has received two or more chemotherapy regimens for the metastatic breast
cancer;

- Documented hypersensitivity to filgrastim, pegfilgrastim, docetaxel, doxorubicin,
dexamethasone and/or its excipients, PEGylated drugs, recombinant proteins.

- Pregnancy or breastfeeding;

- Systemic antibiotic therapy within 72 h prior empegfilgrastim/filgrastim
administration;

- Concomitant radiotherapy (except selective radiotherapy of bone metastases);

- Surgery, radiotherapy (except selective radiotherapy of bone metastases),
administration of any experimental drugs within 30 days prior randomization;

- History of bone marrow/stem cell transplantation;

- Conditions limiting the patient's ability to follow the protocol;

- CTCAE grade 2/4 neuropathy

- HIV, HCV, HBV, T.Pallidum infection(s);

- Acute or active chronic infections.