Detailed explanation of dacomitinib/dacomitinib usage and instructions guide

Dacomitinib/Dacomitinib (Dacomitinib) is a second-generation irreversible epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), mainly used to treat patients with advanced or metastatic non-small cell lung cancer (NSCLC) with EGFR-sensitive mutations. It inhibits the growth and spread of tumor cells by targeting and irreversibly binding to EGFR (including EGFR exon 19 deletion and L858R mutation), HER2 and HER4 receptors, and has a broader and more durable anti-tumor effect than first-generation EGFR-TKIs (such as gefitinib). The following is a complete usage and instruction guide for dacomitinib to help patients and doctors apply this drug more scientifically and standardizedly.

1. Indications and clinical positioning

1. Indications: Dacomitinib is mainly suitable for the first-line treatment of patients with metastatic non-small cell lung cancer (NSCLC) with EGFR sensitive mutations (exon 19 deletion or L858R point mutation). EGFR mutation-positive status must be confirmed by an FDA-approved companion diagnostic.

2. Clinical value:ARCHER 1050 study shows that dacomitinib significantly prolongs progression-free survival (PFS) and overall survival (OS) compared with gefitinib, and is especially beneficial for patients with pre-brain metastasis. It is an important component of the first-line oral targeted regimen in the precision treatment of lung cancer.

2. Detailed explanation of usage

1. Recommended starting dose: 45 mg orally once a day. It is recommended to take the drug at the same time every day, on an empty stomach or with food.

2. Duration of taking the medicine: Continue taking it until the disease progresses or intolerable adverse reactions occur. If the patient experiences severe side effects, temporary discontinuation, dose reduction, or permanent discontinuation of the drug may be considered.

3. Dose adjustment plan: The first dose reduction: from 45 mg to 30 mg once a day; the second dose reduction: from 30 mg to 15 mg once a day; if grade 3 toxicity still occurs at the 15 mg dose, permanent discontinuation of the drug is recommended.

4. Handling of missed doses: If you miss a dose of dacomitinib and it is more than 12 hours before the next dose, you can take it immediately; if it is less than 12 hours, skip this time and do not take it with a double dose.

5. Medication precautions: Avoid using proton pump inhibitors (such as omeprazole) at the same time to avoid reducing drug absorption. Avoid eating grapefruit products for at least one hour before or after oral administration to avoid affecting metabolism.

3. Adverse reactions and management

1. Common adverse reactions:

Skin rash and acneiform dermatitis: Characteristic side effects of EGFR-TKI drugs;

Diarrhea: may occur early in treatment and loperamide needs to be used as needed;

Oral mucositis, dry skin, decreased appetite, paronychia;

Elevated liver enzymes, conjunctivitis, and nail abnormalities.

2. Management suggestions:

Use moisturizers and antibiotic ointments to relieve skin discomfort;

Monitor liver function and electrolyte levels weekly;

For grade ≥3 adverse reactions, the medication should be suspended immediately and supportive treatment should be given, and the dose should be adjusted if necessary.

4. Treatment effect and evaluation

Onset of effect: Some patients may experience symptom relief within 24 weeks after treatmentand tumor shrinkage may be visible at the time of the first imaging evaluation (68 weeks).

Effectiveness evaluation: It is recommended to perform CT or MRI examination every 8 weeks to evaluate the tumor response, monitor changes in side effects, and evaluate whether to continue treatment.

Summary of efficacy advantages: Compared with the first generationEGFR-TKI, dacomitinib has longer PFS (14.7 months vs 9.2 months), lower drug resistance rate, and some of them have potential preventive effects on brain metastasis.

Reference materials:https://www.pfizer.com/products/product-detail/vizimpro