TAFINLAR: Uses, Dosage & Side Effects

What Is TAFINLAR and What Is It Used For?

TAFINLAR contains the active substance dabrafenib mesylate, a potent and selective inhibitor of the BRAF serine/threonine kinase. BRAF is a key protein in the RAS/RAF/MEK/ERK signaling pathway (also known as the MAPK pathway), which regulates cell growth, division, and survival. In normal cells, this pathway is tightly controlled. However, in approximately 40–60% of cutaneous melanomas and a subset of non-small cell lung cancers, a specific mutation in the BRAF gene (most commonly V600E, and less frequently V600K) causes the BRAF protein to become constitutively active, driving uncontrolled cell proliferation and tumor growth.

Dabrafenib was designed to specifically target and inhibit these mutated forms of the BRAF protein. By binding to the ATP-binding site of the mutated BRAF kinase, dabrafenib blocks the downstream signaling through MEK and ERK, effectively shutting down the aberrant growth signal that fuels the cancer. This targeted mechanism of action distinguishes dabrafenib from traditional chemotherapy, which kills rapidly dividing cells indiscriminately. Because dabrafenib specifically targets the mutated BRAF protein, it has potent antitumor activity in BRAF V600 mutation-positive tumors while having less effect on cells with normal (wild-type) BRAF. Importantly, dabrafenib should not be used in patients whose tumors have wild-type BRAF, as paradoxical activation of the MAPK pathway can occur, potentially promoting tumor growth.

A validated test to confirm the presence of a BRAF V600 mutation is mandatory before starting treatment with TAFINLAR. This molecular testing is typically performed on a tumor biopsy sample using techniques such as polymerase chain reaction (PCR) or next-generation sequencing (NGS). Without a confirmed BRAF V600 mutation, TAFINLAR treatment is not appropriate and should not be initiated.

TAFINLAR is approved by the European Medicines Agency (EMA), the U.S. Food and Drug Administration (FDA), and regulatory authorities worldwide for the following indications:

• Unresectable or metastatic melanoma with BRAF V600 mutation: TAFINLAR is used as monotherapy or, more commonly, in combination with trametinib for adult patients with unresectable (cannot be surgically removed) or metastatic (has spread to other parts of the body) melanoma that carries a BRAF V600 mutation. The combination of dabrafenib plus trametinib was shown to be superior to dabrafenib monotherapy in the COMBI-d and COMBI-v trials, with significantly improved progression-free survival, overall survival, and objective response rates.
• Adjuvant treatment of melanoma after complete surgical resection: TAFINLAR is used in combination with trametinib for the adjuvant (post-surgery) treatment of adult patients with stage III melanoma that has a BRAF V600 mutation, after complete resection. The landmark COMBI-AD trial demonstrated that adjuvant dabrafenib plus trametinib significantly reduced the risk of disease recurrence compared with placebo, with durable long-term benefits observed at 5-year follow-up.
• Non-small cell lung cancer (NSCLC) with BRAF V600 mutation: TAFINLAR is used in combination with trametinib for adult patients with advanced or metastatic NSCLC with a BRAF V600 mutation. The BRF113928 study demonstrated clinically meaningful responses and durable disease control in this molecularly defined patient population, leading to regulatory approval.

Melanoma is the most dangerous form of skin cancer, arising from melanocytes (the pigment-producing cells of the skin). When melanoma carries a BRAF V600 mutation, targeted therapy with BRAF and MEK inhibitors has become a cornerstone of treatment, alongside immunotherapy with checkpoint inhibitors. Non-small cell lung cancer accounts for approximately 85% of all lung cancers, and although BRAF V600 mutations are relatively uncommon (occurring in 1–3% of NSCLC cases), the availability of effective targeted therapy has significantly improved outcomes for this molecular subgroup.

What Should You Know Before Taking TAFINLAR?

Contraindications

There are specific situations in which TAFINLAR must not be used. Understanding these absolute contraindications is essential before treatment begins.

• Hypersensitivity: Do not take TAFINLAR if you are allergic to dabrafenib or any of the other ingredients in the capsules (microcrystalline cellulose, magnesium stearate, colloidal silicon dioxide, red iron oxide, titanium dioxide, or hypromellose).
• Wild-type BRAF tumors: TAFINLAR must not be used in patients whose tumors do not carry a confirmed BRAF V600 mutation. In wild-type BRAF tumors, dabrafenib can paradoxically activate the MAPK pathway and potentially accelerate tumor growth. A validated test confirming BRAF V600 mutation status is mandatory before initiating treatment.

Warnings and Precautions

Before and during treatment with TAFINLAR, inform your doctor if any of the following apply to you:

• Liver problems: TAFINLAR is metabolized by the liver, and liver function should be monitored during treatment. Inform your doctor if you have or have had liver disease, elevated liver enzymes, or jaundice. Dose adjustments may be necessary.
• Kidney problems: Fever associated with TAFINLAR can sometimes cause dehydration and acute kidney injury. Tell your doctor if you have existing kidney problems, as close monitoring will be required.
• New cancers (cutaneous and non-cutaneous): TAFINLAR, especially as monotherapy, can increase the risk of developing new primary skin cancers including cutaneous squamous cell carcinoma (cuSCC), keratoacanthoma, basal cell carcinoma, and even new primary melanomas. Non-cutaneous malignancies associated with RAS mutation activation have also been reported. Regular skin examinations by a dermatologist before, during, and for up to 6 months after treatment are essential.
• Heart problems: TAFINLAR in combination with trametinib can cause a decrease in the heart’s pumping ability (left ventricular ejection fraction, or LVEF). Your heart function will be assessed before starting treatment and monitored regularly. Symptoms such as shortness of breath, swelling of the ankles, or persistent fatigue should be reported immediately.
• Eye problems: Uveitis (inflammation inside the eye) and retinal vein occlusion have been reported with TAFINLAR. Symptoms include eye pain, redness, sensitivity to light, or changes in vision. Contact your doctor immediately if you experience any visual disturbances during treatment.
• Bleeding: Serious hemorrhagic events, including intracranial and fatal hemorrhage, have been reported when TAFINLAR is used with trametinib. Inform your doctor if you have any bleeding disorders or are taking blood-thinning medications.
• Skin changes: Besides new skin cancers, TAFINLAR may cause various skin reactions including rash, acneiform dermatitis, erythema, hyperkeratosis, and hand-foot syndrome (palmar-plantar erythrodysaesthesia). Check your skin regularly and report any new or changing skin lesions.
• Sarcoidosis: Cases of sarcoidosis (an inflammatory condition that can affect multiple organs, most commonly the lungs and lymph nodes) have been reported in patients receiving TAFINLAR with trametinib. Symptoms may include persistent cough, shortness of breath, swollen lymph nodes, skin lesions, or eye problems.
• Hemophagocytic lymphohistiocytosis (HLH): This is a rare but serious and potentially life-threatening condition involving excessive immune system activation. Symptoms include persistent fever, enlarged liver and/or spleen, low blood cell counts, and elevated ferritin levels. Seek immediate medical attention if you experience these symptoms.
• Tumor lysis syndrome (TLS): Rapid breakdown of cancer cells can lead to potentially life-threatening metabolic disturbances including kidney failure, heart rhythm abnormalities, and seizures. Your doctor will monitor for this complication, particularly if you have a large tumor burden.
• Diabetes or glucose intolerance: TAFINLAR may increase blood sugar levels. If you have diabetes, your blood glucose should be monitored more frequently during treatment, and your diabetes medications may need adjustment.

Your doctor will perform regular blood tests, imaging studies, skin examinations, eye assessments, and cardiac evaluations to monitor for these potential complications throughout your treatment.

Pregnancy and Breastfeeding

TAFINLAR is not recommended during pregnancy. Animal studies have shown that dabrafenib can cause harm to the developing fetus, including embryolethality and developmental abnormalities. If you are pregnant, think you may be pregnant, or are planning to become pregnant, inform your doctor before starting treatment. If you become pregnant during treatment, your doctor will discuss the risks and benefits of continuing therapy.

It is not known whether dabrafenib or its metabolites are excreted in human breast milk. Because of the potential for serious adverse effects in the breastfed infant, breastfeeding is not recommended during treatment with TAFINLAR and for at least 2 weeks after the last dose.

Dabrafenib may impair male fertility. The effects on spermatogenesis may be irreversible. Men should discuss fertility preservation options, such as sperm cryopreservation, with their doctor before starting treatment.

Driving and Operating Machinery

TAFINLAR may cause fatigue, dizziness, and visual disturbances that could affect your ability to drive or operate machinery. If you experience these side effects, avoid driving or using machines until the symptoms have fully resolved. Discuss with your doctor if you have concerns about performing these activities safely during treatment.

How Does TAFINLAR Interact with Other Drugs?

Dabrafenib is primarily metabolized by CYP2C8 and CYP3A4 enzymes, and it also acts as an inducer of CYP3A4, CYP2C8, CYP2C9, CYP2C19, and CYP2B6. This means that TAFINLAR can both be affected by other drugs and affect the levels of other drugs in the body. Understanding these interactions is critical for safe and effective treatment. Always inform your doctor about all medications, supplements, and herbal products you are taking.

The enzyme-inducing properties of dabrafenib are particularly important because they can significantly reduce the plasma concentrations (and therefore the effectiveness) of many commonly used medications. This effect may persist for several days after TAFINLAR is discontinued, as enzyme induction takes time to reverse. Your doctor may need to adjust the doses of co-administered medications or choose alternative agents that are not significantly affected by CYP enzyme induction.

Major Interactions

Minor Interactions

Because dabrafenib is a potent CYP enzyme inducer, it can potentially affect the metabolism of a wide range of medications beyond those listed above. This includes certain antidepressants, antipsychotics, antiepileptic drugs, opioid analgesics, and proton pump inhibitors. Your oncologist and pharmacist will carefully review your complete medication list to identify and manage any potential interactions. It is important to inform your healthcare team about any new medications, including over-the-counter drugs and dietary supplements, that you start or stop during TAFINLAR treatment.

What Is the Correct Dosage of TAFINLAR?

TAFINLAR capsules are taken orally (by mouth) and must be swallowed whole with a glass of water. The capsules must not be opened, crushed, or chewed, as this could affect the way the drug is absorbed. Each dose should be taken on an empty stomach, which means at least 1 hour before a meal or at least 2 hours after a meal. This requirement is important because food can significantly increase the absorption of dabrafenib, leading to higher plasma levels and potentially increased toxicity.

Adults – Standard Dosing

Combination with Trametinib (MEKINIST)

Dose reductions may be necessary if you experience significant side effects. Your doctor will follow a structured dose reduction scheme. For TAFINLAR, the first dose reduction is to 100 mg twice daily (e.g., one 50 mg plus one 75 mg capsule, or two 50 mg capsules), and the second reduction is to 75 mg twice daily. If further dose reduction below 75 mg twice daily is required, treatment should be permanently discontinued. The availability of both 50 mg and 75 mg capsule strengths allows for flexible dose adjustments.

Children and Adolescents

The safety and efficacy of TAFINLAR in children and adolescents under 18 years of age have not been established. TAFINLAR is not recommended for use in this age group. There are no data available from pediatric clinical trials with dabrafenib capsules for the approved indications.

Missed Dose

Overdose

There is no specific antidote for dabrafenib overdose. If you suspect an overdose, contact your doctor, go to the nearest emergency department, or call your local poison control center immediately. Bring the TAFINLAR packaging with you so healthcare professionals can see exactly what you have taken. Treatment of overdose is supportive, focusing on managing symptoms as they arise. Due to dabrafenib’s high protein binding, hemodialysis is unlikely to be effective in removing the drug from the bloodstream.

What Are the Side Effects of TAFINLAR?

Like all medicines, TAFINLAR can cause side effects, although not everyone experiences them. The side effects and their frequency can differ depending on whether TAFINLAR is used as monotherapy or in combination with trametinib. Below is a comprehensive overview of the side effects grouped by how often they occur. The frequency categories follow international convention.

TAFINLAR Monotherapy Side Effects

Additional Side Effects with TAFINLAR + Trametinib Combination

When TAFINLAR is used together with trametinib, the side effect profile changes. Some side effects become more common (particularly fever), while others that are characteristic of BRAF inhibitor monotherapy (such as cutaneous squamous cell carcinoma and papilloma) become less frequent due to the dual pathway blockade. The following additional or more frequent effects have been observed with the combination:

Serious Side Effects Requiring Immediate Medical Attention

This is not a complete list of all possible side effects. If you notice any side effects not listed here, or if any side effects become severe, please inform your doctor or pharmacist. You can also report side effects to your national medicines agency to help improve safety monitoring.

How Should You Store TAFINLAR?

TAFINLAR capsules do not require any special storage conditions other than being stored below 30°C (86°F). Keep the capsules in the original blister packaging until you are ready to take them, as this protects them from moisture and light. Do not store TAFINLAR in the bathroom or near a sink where it could be exposed to moisture.

Keep TAFINLAR out of the reach and sight of children. Even a single dose can be dangerous to a child. Store the medication in a secure location.

Do not use TAFINLAR after the expiry date (EXP) printed on the outer carton and blister strip. The expiry date refers to the last day of that month. If your capsules appear damaged, discolored, or show any signs of deterioration, do not take them and consult your pharmacist.

Do not throw away any medicines via household waste or wastewater. Ask your pharmacist about how to dispose of unused or expired TAFINLAR capsules. These measures help protect the environment and prevent accidental exposure to others.

What Does TAFINLAR Contain?

Active Ingredient

The active substance is dabrafenib (as dabrafenib mesylate). Each hard capsule contains either 50 mg or 75 mg of dabrafenib. Dabrafenib mesylate is the salt form used in the formulation to ensure adequate stability and bioavailability.

Inactive Ingredients (Excipients)

• Microcrystalline cellulose
• Magnesium stearate
• Colloidal silicon dioxide (colloidal anhydrous silica)
• Red iron oxide (E172)
• Titanium dioxide (E171)
• Hypromellose (HPMC)

The capsule shell is made of hypromellose, and the printing ink contains iron oxide black. These excipients serve various pharmaceutical functions including aiding tablet compression, ensuring uniform drug distribution, and providing the distinctive capsule coloring for identification purposes.

Appearance

TAFINLAR 50 mg capsules: Dark red, opaque hard capsules approximately 18 mm in length, imprinted with “GS TEW” on the capsule body and “50 mg” on the cap. They are supplied in blisters containing 28 or 120 capsules per pack.

TAFINLAR 75 mg capsules: Dark pink, opaque hard capsules approximately 19 mm in length, imprinted with “GS LHF” on the capsule body and “75 mg” on the cap. They are supplied in blisters containing 28 or 120 capsules per pack.

Manufacturer

TAFINLAR is manufactured by Novartis Pharma GmbH, Nuremberg, Germany. The marketing authorization holder is Novartis Europharm Limited, Dublin, Ireland. TAFINLAR is also available under the brand name Finlee in some markets. The product has been approved for use in the European Union, United States, and numerous other countries worldwide.