Docetaxel is a microtubule inhibitor used for the treatment of several types of cancer:

• Breast Cancer (BC): Used as a single-agent therapy for patients with locally advanced or metastatic breast cancer after failure of previous chemotherapy. It is also used in combination with doxorubicin and cyclophosphamide as adjuvant treatment for patients with operable node-positive breast cancer.
• Non-Small Cell Lung Cancer (NSCLC): Used alone in patients with locally advanced or metastatic NSCLC whose disease has progressed after platinum-based chemotherapy. It may also be combined with cisplatin for patients with unresectable, locally advanced, or metastatic NSCLC who have not received prior treatment.
• Castration-Resistant Prostate Cancer (CRPC): Used in combination with prednisone to treat patients with metastatic castration-resistant prostate cancer.
• Gastric Adenocarcinoma (GC): Used together with cisplatin and fluorouracil to treat patients with untreated advanced gastric cancer, including cancers involving the gastroesophageal junction.
• Squamous Cell Carcinoma of the Head and Neck (SCCHN): Used with cisplatin and fluorouracil as induction therapy for patients with locally advanced head and neck cancer.

Docetaxel is an antineoplastic agent that works by disrupting the microtubule network within cells, which is essential for normal cell division and cellular functions. It promotes the assembly of tubulin into stable microtubules and simultaneously prevents their breakdown. Docetaxel binds to free tubulin, reducing the available intracellular tubulin needed for normal microtubule dynamics. This action causes the formation of abnormal microtubule bundles and stabilizes them, ultimately preventing the normal process of mitosis (cell division). Unlike some other spindle-poison drugs, Docetaxel does not change the number of protofilaments in the microtubules to which it binds. Laboratory studies have shown that Docetaxel has strong cytotoxic activity against many murine and human tumor cell lines, as well as freshly removed human tumor cells in clonogenic assays. It has also shown effectiveness against tumor cells that overexpress p-glycoprotein, a protein associated with multidrug resistance in cancer cells.

Administer in a facility equipped to manage possible complications (e.g., anaphylaxis). Administer intravenously (IV) over 1 hr every 3 weeks. PVC equipment is not recommended. Use only a 21 gauge needle to withdraw docetaxel from the vial.

• BC locally advanced or metastatic: 60 mg/m² to 100 mg/m² single agent
• BC adjuvant: 75 mg/m² administered 1 hour after doxorubicin 50 mg/m² and cyclophosphamide 500 mg/m² every 3 weeks for 6 cycles
• NSCLC: after platinum therapy failure: 75 mg/m² single agent
• NSCLC: chemotherapy-naive: 75 mg/m² followed by cisplatin 75 mg/m²
• HRPC: 75 mg/m² with 5 mg prednisone twice a day continuously
• GC: 75 mg/m² followed by cisplatin 75 mg/m² (both on day 1 only) followed by fluorouracil 750 mg/m² per day as a 24-hr IV (days 1–5), starting at end of cisplatin infusion
• SCCHN: 75 mg/m² followed by cisplatin 75 mg/m² IV (day 1), followed by fluorouracil 750 mg/m² per day as a 24-hr IV (days 1–5), starting at end of cisplatin infusion; for 4 cycles
• SCCHN: 75 mg/m² followed by cisplatin 100 mg/m² IV (day 1), followed by fluorouracil 1000 mg/m² per day as a 24-hr IV (days 1–4); for 3 cycles

For all patients:

• Premedicate with oral corticosteroids
• Adjust dose as needed

Docetaxel is metabolized mainly by the CYP3A4 enzyme. Studies have shown that medicines which induce, inhibit, or are metabolized by cytochrome P450 3A4 may affect the metabolism of Docetaxel when used at the same time. Therefore, caution is required when Docetaxel is administered with drugs that influence CYP3A4 activity.

Docetaxel should not be used in patients who have:

• Neutrophil counts below 1500 cells/mm³
• A history of severe hypersensitivity reactions to Docetaxel or to medicines containing polysorbate 80 Severe allergic reactions, including anaphylaxis, have been reported with Docetaxel.

The most frequently reported adverse reactions associated with docetaxel across all indications include infections, neutropenia, anaemia, febrile neutropenia, hypersensitivity reactions, thrombocytopenia, neuropathy, altered taste (dysgeusia), dyspnoea, constipation, loss of appetite, nail disorders, fluid retention, weakness, pain, nausea, diarrhoea, vomiting, mucositis, hair loss, skin reactions, and muscle pain. The incidence of these adverse effects may vary depending on the specific indication. Adverse reactions are categorized according to the condition being treated. Since clinical trials are conducted under varying conditions, the observed adverse reaction rates for one drug cannot be directly compared with those of another drug and may not accurately reflect real-world clinical experience.

Based on animal studies and its mechanism of action, Docetaxel may cause harm to the fetus when used during pregnancy. There is no available information regarding the presence of Docetaxel in human breast milk, its effects on milk production, or its impact on a breastfed child. No animal studies have been conducted to evaluate its effects during lactation.

• Docetaxel should only be administered by a physician experienced in anticancer chemotherapy.
• Patients with liver impairment have a higher risk of severe adverse effects, including fatal gastrointestinal bleeding and toxic death.
• Docetaxel therapy should not be given to patients with neutrophil counts below 1,500 cells/mm³.
• Serious gastrointestinal complications such as enterocolitis, ischemic colitis, and neutropenic enterocolitis, including fatal cases, have been reported.
• Severe hypersensitivity reactions, which may be life-threatening, can occur and require immediate discontinuation of Docetaxel. Patients should be carefully monitored during treatment.
• Treatment-related acute myeloid leukemia (AML) has been reported in some patients receiving Docetaxel.
• The potential carcinogenic risk of Docetaxel has not been fully evaluated in long-term studies.

Only a few cases of Docetaxel overdose have been reported. There is no specific antidote for Docetaxel overdose. In the event of overdose, the patient should be treated in a specialized medical unit where vital functions can be closely monitored. Possible complications of overdose include bone marrow suppression, peripheral nerve damage, and mucositis. Treatment may involve the early administration of G-CSF and other supportive therapies depending on the patient’s condition.

Cytotoxic Chemotherapy

Store Docetaxel at temperatures between 2°C and 25°C, protected from light. Freezing does not damage the product.