Tafinlar® (dabrafenib) is used to treat certain kinds of advanced melanoma. Dabrafenib can be used alone or in combination with a drug called Mekinist® (trametinib).1 Dabrafenib alone is used for melanoma with a mutation called BRAF V600E. The combination of Dabrafenib and trametinib is used to treat melanoma with BRAF V600E or V600K mutation. Your doctor will test for BRAF mutation. Dabrafenib is not used for melanoma with a normal BRAF gene.
Dabrafenib is used when the melanoma:1
- Cannot be removed with surgery (unresectable) or
- Has spread to distant parts of the body (metastasized)
- As adjuvant (additional) treatment for melanoma with BRAF V600E or V600K mutations after the melanoma has been surgically removed in people with disease in the lymph nodes (in combination with trametinib)
Dabrafenib does not come in generic form. Dabrafenib is similar to Zelboraf® (vemurafenib), another drug that is approved to treat certain forms of unresectable or metastatic melanoma.
How does Dabrafenib work?
Dabrafenib is a type of medication called a kinase inhibitor.1 It works by blocking certain proteins that pass along signals for cell growth. One of the proteins is called BRAF.
Mutations in the gene (instructions) for BRAF are found in approximately one-third of melanoma cases.2 V600E and V600K are BRAF mutation subtypes, with V600E being more common in melanoma. This subtype makes up approximately 60% of the BRAF mutations in melanoma.3 About 8% of BRAF mutations are the V600K subtype.4
BRAF proteins have a role in a pathway called MAPK (also called ERK). These proteins are part of a chain of events that allow cells to grow and survive. Normally, there are mechanisms that turn each protein “on” and “off,” keeping the cell processes under control. Certain mutations cause BRAF to stay “on,” sending continuous signals for uncontrolled cell growth.5
Dabrafenib turns the BRAF protein off. It is called a targeted therapy because it targets one feature that makes cancer cells different from normal cells.
Trametinib is a drug that inhibits a protein called MEK. Dabrafenib and trametinib can be used together to target the MAPK pathway at two points. This combination stops or slows the growth of melanomas with BRAF mutations better for some people than either drug alone.1
Before taking dabrafenib, read the Medication Guide that comes in the package. Follow your doctor’s instructions for taking Dabrafenib.
Dabrafenib comes as a capsule that you take by mouth.1 Patients should take their medication as prescribed by their doctor. Patients should talk to their doctor if they have any questions, or if they have questions regarding their dabrafenib regimen.
Based on your doctor’s instructions, you will typically continue taking dabrafenib until the cancer progresses or the side effects are unacceptable, but this may differ if your doctor is prescribing dabrafenib for adjuvant treatment.1
What are the side effects of Dabrafenib?
Taking dabrafenib alone or with trametinib can cause other cancers, such as another type of skin cancer known as cutaneous squamous cell carcinoma, keratoacanthoma, new melanoma lesions, or basal cell carcinoma. Possible signs of new cancers include: new wart, skin sore, reddish bump, or mole that changes in size or color (patients should tell their doctor if they notice any of these skin changes).
The most common side effects of Dabrafenib alone or with trametinib include:
- Thickening of the skin
- Joint aches
- Hair loss
- Skin reaction on the hands or feet
Less common but serious side effects include:
- Bleeding problems in the brain or stomach
- Heart problems
- Eye problems
- Severe skin reaction
- Increased blood sugar
- Low red blood cells (from a specific type of anemia)
Dabrafenib may make it difficult to get pregnant or father a child. If this is a concern for you, discuss this with your doctor.
This is not an exhaustive list of all potential side effects of dabrafenib. Talk to your healthcare provider or pharmacist for further information.
Who should not take Dabrafenib?
If you are pregnant, plan to become pregnant, or are breastfeeding or plan to breastfeed, talk with your doctor. Dabrafenib can cause harm to a developing fetus and should not be taken by women who are pregnant.2 While taking Dabrafenib, females who can become pregnant should use contraceptives during treatment and for a period of time after completing treatment (patients should discuss appropriate birth control methods, and how long they need to use them, with their doctor). Females should not breastfeed during Dabrafenib treatment and for a period of time following the final dose (patients should discuss breastfeeding considerations with their doctor).
While taking Dabrafenib, males with female partners who can become pregnant should always use a condom during sex throughout treatment and for a period of time after completing treatment (patients should discuss appropriate birth control methods, and how long they need to use them, with their doctor).
Tell your doctor about any other medical conditions you have, especially:1
- Bleeding problems
- Heart problems
- Eye problems
- Liver problems
- Kidney problems
- An enzyme deficiency called glucose-6-phosphate dehydrogenase (G6PD)
Tell your doctor if you have had or are planning to have surgery, dental work, or other medical procedures.
What precautions are needed when taking Dabrafenib?
Regular skin exams are needed while taking Dabrafenib.1 Your doctor will do a skin exam before you start this medication. You will need skin exams every 2 months while taking Dabrafenib and for up to 6 months afterward. Your doctor will also look for non-skin cancers.
Before starting treatment with dabrafenib, patients should tell their doctor about all medications (prescription and over-the-counter), herbal supplements, and vitamins they are taking.