Efficacy of Neoadjuvant Subcutaneous Trastuzumab-Pertuzumab in Algerian Women With Locally Advanced HER2 Positive Breast Cancer

Evaluation of the Efficacy of Subcutaneous Trastuzumab-Pertuzumab Combination in Neoadjuvant Treatment of Non-Metastatic HER2-Positive Breast Cancer in Algerian Women

This study aims to find out how effective and well-tolerated the subcutaneous form of trastuzumab-pertuzumab (known as Phesgo) is when given before surgery (neoadjuvant treatment) to Algerian women with early stage, HER2-positive breast cancer.

The study will take place in three oncology centers in Algeria (Blida, Aïn Defla, Médéa) and include around 70 adult women diagnosed with non-metastatic HER2-positive breast cancer. Participants will receive Phesgo along with standard chemotherapy over about 18 weeks, followed by surgery.

The main goal is to measure how many women achieve complete destruction of invasive cancer in the breast and nearby lymph nodes (pathological complete response, pCR). We will also look at other outcomes such as how many women can keep their breast, any side effects, quality of life, satisfaction with treatment, and factors that might predict response.

Results from this real-world study will help assess whether Phesgo can simplify treatment delivery, reduce hospital burden, and improve care access in Algeria where healthcare resources are often stretched.

Inclusion Criteria:

• Female participants aged 19 years or older.
• Histologically confirmed HER2-positive breast cancer (by immunohistochemistry and/or in situ hybridization), non-metastatic.
• Candidate for neoadjuvant therapy according to local clinical practice.
• Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2.
• Left ventricular ejection fraction (LVEF) ≥ 50%.
• Signed written informed consent.

Exclusion Criteria:

• Evidence of distant metastases.
• Prior anti-HER2 therapy.
• Known contraindications to trastuzumab or pertuzumab.
• Pregnancy or breastfeeding.
• Disease progression during neoadjuvant treatment (if already started).
• Refusal of surgery.
• Withdrawal of consent.