Dabrafenib is a selective BRAF serine-threonine kinase inhibitor that exerts its anti-tumor effect by specifically targeting the BRAF V600E/V600K mutation site. Developed by Novartis, it was first approved by the FDA on May 29, 2013.
Dabrafenib Indications
1. Melanoma
(1) Dabrafenib, in combination with trametinib, is used as adjuvant therapy after complete resection of melanoma with BRAF V600E or V600K mutations and lymph node involvement. It can also be used as a monotherapy for the treatment of unresectable or metastatic melanoma in patients with BRAF V600E mutations (designated as an orphan drug by the FDA).
(2) Dabrafenib, in combination with trametinib, is used for the treatment of unresectable or metastatic melanoma in patients with BRAF V600E or V600K mutations (designated as an orphan drug by the FDA). (3) Before initiating dabrafenib monotherapy, an FDA-approved diagnostic test (e.g., the THxIDBRAF kit) is required to confirm the presence of the BRAF V600E mutation; the presence of BRAF V600E or V600K is also required before initiating combination therapy.
(4) Dabrafenib is not recommended for patients with wild-type BRAF solid tumors; its safety and efficacy have not been established.
2. Non-Small Cell Lung Cancer
(1) Dabrafenib in combination with trametinib is used to treat metastatic non-small cell lung cancer (NSCLC) with the BRAF V600E mutation (designated as an orphan drug by the FDA).
(2) Before initiating dabrafenib treatment, an FDA-approved diagnostic test (e.g., the THxIDBRAF kit) is required to confirm the presence of the BRAF V600E mutation.
(3) Dabrafenib is not recommended for patients with wild-type BRAF solid tumors; its safety and efficacy have not been established.
3. Undifferentiated Thyroid Carcinoma
(1) Dabrafenib in combination with trametinib is used to treat patients with locally advanced or metastatic anaplastic thyroid carcinoma who have a BRAF V600E mutation when no satisfactory local treatment alternative exists (designated as an orphan drug by the FDA).
(2) An FDA-approved diagnostic test (e.g., the THxIDBRAF kit) is required to confirm the presence of the BRAF V600E mutation before initiating treatment; currently, no FDA-approved diagnostic test is available to detect BRAF V600E in solid tumors other than melanoma and non-small cell lung cancer.
(3) Not recommended for patients with wild-type BRAF solid tumors; safety and efficacy have not been established.
4. Solid Tumors
(1) Dabrafenib in combination with trametinib is used to treat adult and pediatric patients ≥1 year of age with unresectable or metastatic solid tumors with a BRAF V600E mutation who have progressed after prior treatment and have no satisfactory alternative therapy. Designated as an orphan drug by the FDA for malignant gliomas.
(2) Testing (e.g., the THxIDBRAF kit) is required before initiating treatment to confirm the presence of the BRAF V600E mutation; currently, there are no FDA-approved diagnostic tests for detecting BRAF V600E in solid tumors other than melanoma and NSCLC.
(3) Due to intrinsic resistance to BRAF inhibition, this treatment is not suitable for patients with BARE-mutant colorectal cancer. It is not recommended for patients with wild-type BRAF solid tumors; safety and efficacy have not been established.
5. Low-grade gliomas
(1) Dabrafenib in combination with trametinib is used to treat pediatric patients ≥1 year of age with BRAF V600E-mutant low-grade gliomas requiring systemic therapy.
(2) Testing (e.g., the THxIDBRAF kit) is required before initiating treatment to confirm the presence of the BRAF V600E mutation; currently, there are no FDA-approved diagnostic tests for detecting BRAF V600E in low-grade gliomas.
(3) It is not recommended for patients with wild-type BRAF solid tumors; safety and efficacy have not been established.
Dabrafenib Dosage and Administration
1. Recommended Dosage for Children
(1) Oral (Capsules)
Pediatric patients ≥1 year of age: Patients weighing ≥51 kg: 150 mg dabrafenib (two 75 mg capsules) twice daily; patients weighing 38-50 kg: 100 mg twice daily; patients weighing 26-37 kg: 75 mg twice daily. Continue treatment until disease progression or unacceptable toxicity occurs.
The recommended dose of dabrafenib capsules has not been established for patients weighing <26 kg.
(2) Oral Suspension Tablets
8-9 kg: 20 mg dabrafenib suspension twice daily.
10-13 kg: 30 mg dabrafenib suspension twice daily.
14-17 kg: 40 mg dabrafenib suspension twice daily.
18-21 kg: 50 mg dabrafenib suspension twice daily. 22-25 kg: 60 mg dabrafenib suspension twice daily.
26-29 kg: 70 mg dabrafenib suspension twice daily.
30-33 kg: 80 mg dabrafenib suspension twice daily.
34-37 kg: 90 mg dabrafenib suspension twice daily.
38-41 kg: 100 mg dabrafenib suspension twice daily.
42-45 kg: 110 mg dabrafenib suspension twice daily.
46-50 kg: 30 mg dabrafenib suspension twice daily.
≥51 kg: 150 mg dabrafenib suspension twice daily.
2. Recommended Adult Dosage:
150 mg (two 75 mg capsules) twice daily. Continue treatment for up to 1 year or until disease progression or unacceptable toxicity occurs.
3. Toxicity and Dosage Adjustment
For patients experiencing adverse reactions, the dose may be reduced, or treatment may be temporarily interrupted or discontinued. If the patient cannot tolerate the 50 mg twice daily dosing regimen, dabrafenib capsules should be permanently discontinued.
Due to space limitations, please refer to the original drug package insert for detailed information. Please follow your doctor's instructions for specific medication use.
Dabrafenib Adverse Reactions
1. Adverse reactions of dabrafenib monotherapy in adults (≥20%): hyperkeratosis, headache, fever, arthralgia, cysts, alopecia, palmoplantar erythroplakia syndrome (hand-foot syndrome).
2. Adverse reactions (≥20%) of dabrafenib combined with trametinib in the treatment of previously untreated adult patients with unresectable or metastatic melanoma: fever, rash, chills, headache, arthralgia, cough.
3. Adverse reactions (≥20%) of dabrafenib combined with trametinib as adjuvant therapy in adult patients with melanoma: fever, fatigue, nausea, headache, rash, chills, diarrhea, vomiting, arthralgia, myalgia.
4. Adverse reactions (≥20%) of dabrafenib combined with trametinib in the treatment of adult patients with metastatic non-small cell lung cancer: fever, fatigue, nausea, vomiting, diarrhea, dry skin, decreased appetite, edema, rash, chills, bleeding, cough, dyspnea.
5. Adverse reactions (≥20%) of dabrafenib combined with trametinib in the treatment of adult patients with solid tumors: fever, fatigue, nausea, rash, chills, headache, bleeding, cough, vomiting, constipation, diarrhea, myalgia, arthralgia, edema.
6. Adverse reactions (≥20%) of dabrafenib combined with trametinib in pediatric patients with solid tumors: fever, rash, vomiting, fatigue, dry skin, cough, diarrhea, acneiform dermatitis, headache, abdominal pain, nausea, bleeding, constipation, paronychia.
7. Adverse reactions (≥20%) of dabrafenib combined with trametinib in pediatric patients with low-grade gliomas: fever, rash, headache, vomiting, myencephalopathy, fatigue, diarrhea, dry skin, nausea, bleeding, abdominal pain, acneiform dermatitis.
Due to space limitations, please refer to the original drug instructions for detailed information. Specific medication use should be followed as directed by your doctor.
Precautions for dabrafenib:
1. New primary malignancies: New primary cutaneous or non-cutaneous malignancies have been reported in patients receiving BRAF inhibitors (including dabrafenib). 1. Dermatological evaluation: Perform dermatological evaluation before starting dabrafenib, every 2 months during treatment, and up to 6 months after discontinuation. Monitor for signs and symptoms of new non-cutaneous malignancies. If a new primary RAS mutation-positive non-cutaneous malignancy develops, permanently discontinue treatment.
2. Tumor promotion of wild-type BRAF tumors: In vitro evidence of increased proliferation of BRAF wild-type cells exposed to BRAF inhibitors. Not recommended for patients with wild-type BRAF solid tumors.
3. Bleeding: Bleeding (sometimes fatal) during dabrafenib/trametinib combination therapy, including intracranial hemorrhage, retroperitoneal hemorrhage, subarachnoid hemorrhage, or gastrointestinal bleeding. If a bleeding event occurs, dose adjustment or discontinuation of treatment may be necessary.
4. Cardiomyopathy: Reporting of cardiomyopathy (defined as an absolute decrease in LVEF of ≥10% from baseline and below the level of institution-specific LLN). Assess LVEF by echocardiography or multi-gate radionuclide angiography (MUGA) before treatment initiation and 1 month after treatment initiation, and then every 2–3 months during treatment. If left ventricular dysfunction occurs, treatment may need to be interrupted.
5. Uveitis Uveitis has been reported. If uveitis occurs, symptomatic treatment with ophthalmic corticosteroids or mydriatics may be necessary. Monitor patients for signs and symptoms of uveitis (e.g., visual changes, photophobia, eye pain). If ocular toxicity occurs, treatment may need to be interrupted, the dose reduced, or the drug discontinued and/or ocular treatment initiated.
6. Severe Febrile Reactions Severe febrile drug reactions (including fever with hypotension, chills, dehydration, or renal failure) have been reported. The incidence and severity of fever observed during dabrafenib/trametinib combination therapy are increased compared to dabrafenib alone.
7. Severe Skin Toxicity Severe skin adverse reactions (SCARs) have been reported in post-marketing experience with dabrafenib in combination with trametinib, including Stevens-Johnson syndrome and drug reactions with eosinophilia and systemic symptoms (DRESS). Monitor for new or worsening severe skin toxicities. Dose adjustment or discontinuation of treatment may be necessary. If SCAR occurs, permanently discontinue the medication. For other skin toxicities, discontinue dabrafenib if intolerable or severe. Patients whose skin toxicities improve or resolve within 3 weeks should resume treatment at a lower dose; if skin toxicities do not improve within 3 weeks, permanently discontinue treatment.
8. Hyperglycemia Hyperglycemia reported by patients receiving dabrafenib treatment requires a dose increase or initiation of insulin or oral hypoglycemic agents. Monitor serum glucose levels in patients with a history of diabetes or hyperglycemia based on clinical condition before initiating treatment. Initiate and optimize antihyperglycemic therapy according to clinical indications.
9. Glucose-6-phosphate dehydrogenase deficiency There is a potential risk of hemolytic anemia in patients with glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. Closely monitor patients with G-6-PD deficiency for hemolytic anemia.
10. Hemophagocytic lymphohistiocytosis Dabrafenib combined with trametinib may cause hemophagocytic lymphohistiocytosis (HLH). If HLH is suspected, discontinue treatment. If diagnosed, discontinue treatment and begin appropriate HLH management.
11. Fetal/Neonatal Morbidity and Mortality: May cause fetal harm based on mechanism of action and animal findings; teratogenicity and embryotoxicity in animals. Verify the pregnancy status of women of reproductive potential before initiating treatment. Women of reproductive potential are advised to use an effective non-hormonal contraceptive during treatment and for 2 weeks after the last dose. Women are advised to contact their clinician if pregnancy is suspected or confirmed.
