Why Are Tafinlar and Mekinist Used Together for Metastatic Melanoma?

In the past, a diagnosis of metastatic melanoma meant limited treatment options and an uncertain future. But we’ve seen a boom in new-and-improved cancer treatments over the years, and health outcomes are looking more positive. Cancer mutation-fighting medications are one important reason for this. 

Alongside other genetic mutations, researchers have discovered that medications that fight BRAF V600 mutations can help certain people living with melanoma. Tafinlar (dabrafenib) is one of these medications, as it’s a type of BRAF inhibitor. Tafinlar has many possible benefits, but resistance is a common problem. Often, a little extra assistance is needed from another medication to make it as useful as possible. 

Here, we talk about why Tafinlar and Mekinist (trametinib) are used together to treat metastatic melanoma. 

What is Tafinlar?

Tafinlar is an oral medication used to treat a type of skin cancer called melanoma. It's called a BRAF kinase inhibitor — it specifically treats melanomas with a BRAF V600 mutation (a type of genetic mutation). It can be used alone or with another medication, called Mekinist, for melanoma that can’t be removed with surgery or that has spread (metastasized) to other parts of your body.

How does Tafinlar work?

Normally, kinases are proteins that control cell growth. But cancer can change these kinases so that they are always “on,” resulting in uncontrolled cell growth. Uncontrolled cell growth leads to cancer growth. BRAF mutations are the cause of some of these unregulated kinases.

This is where medications like Tafinlar can step in. Tafinlar can block this activity and slow down cancer cell growth. 

What is Mekinist?

Mekinist is another oral medication used to treat melanoma. It can also treat BRAF V600-mutated melanoma that can’t be removed with surgery or has spread to other parts of your body. 

However, Mekinist works slightly differently than Tafinlar — it’s called a MEK inhibitor. 

How does Mekinist work?

MEK is another kinase that controls cell growth in melanoma. It’s similar to BRAF kinases, but it works at a different step of the cancer cell development process. Mekinist can block MEK activity to help slow down cancer growth.

Note: Tafinlar and Mekinist are not considered chemotherapy. They’re targeted medications. They “target” specific signals (BRAF and MEK kinases) involved in cancer growth. 

Why are Taflinlar and Mekinist used together for metastatic melanoma?

As mentioned, Tafinlar and Mekinist are frequently used together to treat metastatic melanoma. Studies show that using these medications together is more effective than using either medication alone. But why is this?

BRAF and MEK are involved in the same chemical pathway that melanoma cells use to grow and spread. But they each have distinct roles to play at different spots in this pathway. 

It may be intuitive to think that blocking this pathway at any point would be sufficient. But we’ve learned that using only one medication at a time can eventually cause resistance. This is because tumor (cancer) cells are able to turn on other signals of the pathway — like MEK — to keep uncontrolled cell growth going. 

So, it’s better to cut off this pathway in multiple spots. Using both BRAF and MEK inhibitors at the same time slows tumor cell growth at multiple steps within the pathway. This lowers the chance of resistance. 

How effective are Tafinlar and Mekinist for metastatic melanoma?

Tafinlar and Mekinist have many possible benefits. They can help slow down how fast your cancer grows, they can prolong your life, and they can help make your tumor smaller.

Slowing down cancer cell growth

Taking Tafinlar and Mekinist together can slow down your cancer’s growth. They can extend the amount of time it takes for your cancer to grow or spread compared to taking a BRAF inhibitor by itself. 

For instance, in one study, people who took both Tafinlar and Mekinist for 1 year went about 4 extra months before seeing any additional signs of cancer growth. This is compared to people who took a BRAF inhibitor by itself. 

In another study, the combination increased that time by just about half of a month. But after 3 years, about 22% of people had no tumor growth or spread when taking the combination. This is compared to 12% of people who were taking a BRAF inhibitor alone. 

Extending life expectancy

The combination can also help extend life expectancy. 

In one of the same studies discussed earlier, 72% of people were still alive after taking both medications for 1 year. By comparison, 65% of people who only took a BRAF inhibitor were still alive. Among those who took both medications for at least a year, the chance of death went down by about 30%. 

Longer-term data is also available. After 3 years, 45% of people who were taking Tafinlar and Mekinist — and 32% of people taking a BRAF inhibitor alone — were still alive. After 5 years, about 34% of people taking the combination were still alive. 

Making tumors smaller

Studies also show that Tafinlar and Mekinist can boost the likelihood of seeing signs of tumor shrinkage or disappearance compared to taking a BRAF inhibitor by itself. 

However, for all of these results, know that everyone's a little different. You’re far more than just a statistic, and results can vary. You should discuss what results to expect with your care team. 

Tafinlar and Mekinist side effects

Tafinlar and Mekinist can cause a number of side effects. The most common side effects include:

• Fever

• Rash 

• Chills

• Headache

• Joint and muscle aches

• Fatigue

• Nausea and vomiting

• Diarrhea

• High blood pressure

• Swelling of the arms or legs

• Cough

Rare but serious side effects are also possible. These include:

• Developing other types of cancer

• Certain heart problems, including heart failure

• Certain eye problems, including eye pain or vision changes

• Colon or lung inflammation

• Gastrointestinal (GI) tract perforation, which is when there is a hole in the wall of your GI tract

• A higher risk for bleeding

• Blood clots

• Serious skin problems 

• High fever with shaking, low blood pressure, or dehydration

Be sure to contact your healthcare provider right away if you experience — or think you’re experiencing — any serious or worrisome side effects.

How much do Tafinlar and Mekinist cost?

Tafinlar and Mekinist are expensive. Back when Tafinlar was first approved in 2013, the list price for the two medications together was reported as more than $15,000 per month. Prices have only gone up since then, but there are ways you can save.

If you have prescription insurance, your plan may cover all or a portion of your copay. It’s a good idea to contact your insurance provider to see what your coverage looks like. 

If you don’t have insurance or are underinsured, GoodRx coupons are available to help lower these prices. However, this could still leave you with a large bill due to the high cost of these medications. So, other options are also available for you to consider. 

Novartis, the manufacturer of Tafinlar and Mekinist, has a few financial assistance programs available. One option is the Novartis Oncology Universal Co-Pay Program that can take your payments down to as low as $0 a month. You may qualify for this program if you have private (commercial) insurance. 

Another option is from a program called Patient Assistance Now Oncology (PANO). This program can set you up with resources to determine if you qualify for free medication from the manufacturer or for other financial assistance resources. Call 1-800-282-7630 or visit Novartis Oncology Patient Support online for more details. 

The specialty pharmacy that dispenses your Tafinlar and Mekinist prescriptions can also help connect you with additional ways to save. 

Why trust our experts?

Written by:

Rachel Feaster, PharmD, BCOP, BCPS

Rachel Feaster has over 10 years of professional experience in ambulatory, inpatient, pharmacogenomics, and oncology care. She is board certified in oncology and pharmacotherapy.

Edited by:

Joshua Murdock, PharmD, BCBBS

Joshua Murdock, PharmD, BCBBS, is a licensed pharmacist in Arizona, Colorado, and Rhode Island. He has worked in the pharmacy industry for more than 10 years and currently serves as a pharmacy editor for GoodRx.

Reviewed by:

Sonja Jacobsen, PharmD, BCPS, BCOP

Sonja Jacobsen, PharmD, BCPS, BCOP,  is a clinical oncology pharmacy specialist currently practicing in Seattle. She has been practicing as a pharmacist since 2015 and is licensed to practice in Washington state and North Carolina.

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