Comparing Efficacy and Safety Between Pertuzumab® and Perjeta® in Neoadjuvant Treatment of HER2+ Breast Cancer

This study was a phase III, multicenter, triple-blind , equivalency clinical trial to determine the therapeutic efficacy and safety between Pertuzumab® (CinnaGen Co.) compared to originator pertuzumab in HER2-positive early breast cancer patients.

Patients stratified dynamically according to two factors: type of breast cancer (inflammatory, locally and operable) and estrogen/ progesterone receptor (ER/PR) (positive or negative) with 1:1 allocation ratio.

Study drugs were administered intravenously on a 3-weekly schedule and were given consecutively on the same day in the following sequence: trastuzumab, followed by pertuzumab, carboplatin, and docetaxel (TCHP regimen).

The primary endpoint was breast pCR (bpCR). Secondary efficacy endpoints included total pCR (tpCR); objective response rate (ORR) and rate of breast-conserving surgery (BCS) for patients for whom mastectomy was planned before treatment (T2-3).

During this study, adverse events (AEs) were monitored continuously. As an adverse event of special interest (AESI), left ventricular ejection fraction (LVEF) decreased was monitored and assessed by echocardiography throughout the study. Immunogenicity was also assessed.

Inclusion criteria

• Female patients aged 18-70 years.
• Diagnosed with locally advanced (T2-3, N2-3, M0 or T4a-c, any N, M0), inflammatory (T4d, any N, M0) or operable (T2-3, N0-1, M0), invasive breast cancer.
• Primary tumor > 2 cm in diameter.
• HER2 positive breast cancer confirmed (Tumors must be IHC 3+ or FISH/CISH + for IHC 2+ tumors).
• Baseline LVEF ≥ 55% measured by echocardiography.
• Performance status ECOG ≤ 1
• Signed informed consent.

Exclusion criteria

• Metastatic disease (Stage IV) or bilateral breast cancer.
• Previous anticancer therapy or radiotherapy for any malignancy.
• Other malignancy, except for carcinoma in situ of the cervix or basal cell carcinoma.
• Received any investigational treatment within 4 weeks of study start.
• At least 4 weeks since major surgery.
• Uncontrolled hypertension (systolic > 150 and/or diastolic > 100), unstable angina, CHF of any NYHA classification, serious cardiac arrhythmia requiring treatment, history of myocardial infarction within 6 months of enrollment.
• Hematological, biochemical and organ dysfunction:

• Inadequate bone marrow function: Absolute Neutrophil Count (ANC) < 1500 cells/ µL, Platelet count < 100,000 cells/ µL and Hb < 9 g/dL).
• Impaired liver function: serum [total] bilirubin > 1.25 x ULN, AST/ALT > 1. 5 x ULN with ALP > 2.5 x ULN
• Inadequate renal function: serum creatinine > 1.5 x ULN.
• Dyspnea at rest or other diseases which require continuous oxygen therapy.
• Severe uncontrolled systemic disease (e.g., clinically significant cardiovascular, pulmonary, metabolic, etc).
• Current chronic daily treatment with corticosteroids (dose of ≥10 mg Oral prednisolone, or equivalent [excluding inhaled steroids])
• Subjects with known infection with HIV, HBV, and HCV.
• Known hypersensitivity to any of the study drugs or excipients.
• Pregnant and/or lactating women or subjects with reproductive potential not willing to use effective methods of contraception.
• Subjects assessed by the investigator to be unable or unwilling to comply with the requirements of the protocol (e.g.: physical, psychological and mental problems)