Targeted cancer therapy (HER2-directed monoclonal antibodies)
Last reviewed July 2026
Who is this for?
Pertuzumab and Trastuzumab (sold as Phesgo in Nigeria) is a combination of two cancer-fighting medicines that work together by targeting a specific protein called HER2 on the surface of certain breast cancer cells, blocking the signals that tell cancer cells to grow and multiply.
Bind to human epidermal growth factor receptor 2 (HER2) on cancer cells, blocking ligand activation and preventing HER2 dimerization, which inhibits downstream signaling pathways (PI3K/Akt and MAPK) that drive tumor cell proliferation and survival. Additionally, promote antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP) to enhance immune-mediated destruction of HER2-positive cancer cells.
HER2-positive breast cancer, including early-stage breast cancer before or after surgery, and breast cancer that has spread to other parts of the body
Prescription Required
You need a doctor's prescription to buy this drug.
Explore this drug
If you miss a scheduled appointment for your injection, contact your cancer treatment centre as soon as possible to reschedule. Your doctor will decide whether you need the larger loading dose again or can continue with the regular dose, depending on how long you have waited.
Only receive this medicine at a recognised cancer treatment centre with qualified oncologists; never buy or accept it from unverified sources. Your doctor should check your heart function regularly with scans before and during treatment. Do not share this medication or let anyone administer it who is not a trained healthcare professional.
Avoid using with other medicines that can weaken the heart (like doxorubicin or other anthracycline chemotherapy drugs) at the same time, as this increases the risk of heart damage. Always tell your oncologist about every medicine, herb, or supplement you are taking. There is no specific alcohol interaction, but alcohol can worsen side effects like nausea and tiredness, so it is best to limit or avoid it during treatment.
Check your specific combination
Is it safe to take Pertuzumab; with your other drugs?
This medicine is NOT safe during pregnancy, as it can cause serious harm or death to the unborn baby. Women must use effective contraception during treatment and for at least 7 months after the last dose. It is also not recommended while breastfeeding.
Store in a refrigerator (2°C to 8°C). Do not freeze. Keep the vial in its original carton to protect it from light. In Nigeria's hot climate, this medicine must stay refrigerated at all times; it cannot be left out at room temperature for long. This is handled by your hospital or pharmacy. Keep away from children.
For information only: not medical advice. Always talk to a doctor or pharmacist before changing your medication.
Names this drug is sold under, especially in Nigerian and West African pharmacies
No brand names recorded for Pertuzumab; Trastuzumab yet.
Counterfeit Drug Warning
Fake drugs are a serious problem in Nigeria. Always buy from a registered pharmacy. If the packaging looks different from what is described above, do not use it.