Is trastuzumab (Herceptin) given with neutropenia (low neutrophil count)?

From the Guidelines

Trastuzumab can be given to patients with neutropenia, but careful monitoring is required. Trastuzumab itself does not typically cause neutropenia as its primary side effect, unlike many chemotherapy agents. However, when trastuzumab is administered as part of combination therapy with chemotherapy drugs (which is common in HER2-positive breast cancer treatment), the chemotherapy components may cause neutropenia. In cases of severe neutropenia (absolute neutrophil count <500/mm³), physicians may consider temporarily delaying chemotherapy components while continuing trastuzumab, or using growth factors like filgrastim to support neutrophil counts 1. The decision to continue trastuzumab during neutropenia is based on the severity of neutropenia, the patient's clinical status, and the risk of infection. This approach is reasonable because trastuzumab works by targeting HER2 receptors on cancer cells through a different mechanism than cytotoxic chemotherapy, making it less likely to worsen bone marrow suppression. Regular complete blood count monitoring is essential throughout treatment to assess neutrophil recovery and guide therapy adjustments.

Some key considerations for managing neutropenia in patients receiving trastuzumab include:

• Monitoring absolute neutrophil count regularly to assess the severity of neutropenia
• Temporarily delaying chemotherapy components if severe neutropenia occurs, while continuing trastuzumab
• Using growth factors like filgrastim to support neutrophil counts if necessary
• Assessing the patient's clinical status and risk of infection to guide therapy adjustments
• Being aware of the potential for increased risk of neutropenia and febrile neutropenia in older adults, as well as the need for cautious monitoring and appropriate dose reductions or interruptions for adverse event management 1.

It's also important to note that trastuzumab can be given for 1 year, with cardiac monitoring, and using either the weekly or the every-3-weekly schedule 1. The optimal delivery of anticancer agents, including trastuzumab, requires a healthcare delivery team experienced in the use of anticancer agents and the management of associated toxicities in patients with cancer.

From the FDA Drug Label

1. 5 Exacerbation of Chemotherapy-Induced Neutropenia In randomized, controlled clinical trials, the per-patient incidences of NCI-CTC Grade 3 to 4 neutropenia and of febrile neutropenia were higher in patients receiving trastuzumab in combination with myelosuppressive chemotherapy as compared to those who received chemotherapy alone

• Trastuzumab can exacerbate chemotherapy-induced neutropenia.
• The incidence of NCI-CTC Grade 3 to 4 neutropenia and febrile neutropenia is higher in patients receiving trastuzumab with myelosuppressive chemotherapy compared to those receiving chemotherapy alone 2.

From the Research

Trastuzumab and Neutropenia

• Trastuzumab is a humanized monoclonal antibody used in the treatment of breast cancer, particularly in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer 3.
• While trastuzumab has been shown to reduce the risk of relapse in breast cancer patients, it can cause serious side effects, including neutropenia 3.
• A case study reported a 45-year-old woman with breast cancer who developed severe neutropenia (grade 3) after receiving trastuzumab in the adjuvant setting 3.
• The patient's neutropenia was directly related to trastuzumab, and stopping the treatment led to the normalization of neutrophil counts and improvement of the patient's condition 3.

Management of Neutropenia

• Febrile neutropenia is a serious complication of chemotherapy, with a mortality rate of 2% to 21% 4.
• Prophylactic antibiotics or granulocyte colony-stimulating factor (G-CSF) can be used to prevent infections and improve survival in cancer patients undergoing chemotherapy 4.
• G-CSF has been shown to reduce the incidence of febrile neutropenia and shorten the duration of neutropenia 5, 6.
• The use of prophylactic G-CSF should be considered for patients at high risk of febrile neutropenia, such as elderly patients or those receiving high-risk chemotherapy regimens 6.

Trastuzumab and Neutropenia in Clinical Practice

• Trastuzumab is often administered in combination with other chemotherapy agents, such as docetaxel and cyclophosphamide, which can increase the risk of neutropenia 6.
• The incidence of febrile neutropenia during docetaxel and cyclophosphamide chemotherapy can be high, and primary prophylactic G-CSF can reduce the risk of febrile neutropenia 6.
• Clinicians should be aware of the potential for trastuzumab to cause neutropenia and monitor patients closely for signs of infection or neutropenia 3.