Vemurafenib (Zelboraf®) + Cobimetinib (Cotellic™)

Cancer researchers are developing new ways to treat advanced melanoma with greater success for patients. Targeted therapy is a new, effective treatment option that can shrink cancer cells and tumors and help patients with melanoma live longer.

Vemurafenib (Zelboraf) and cobimetinib (Cotellic) are a combination therapy that blocks the activity of different molecules within cancer cells that cause the cancer to grow and spread. This combination of targeted therapies treats advanced melanoma more effectively than the single drugs while producing less serious side effects.

What Are Vemurafenib (Zelboraf) + Cobimetinib (Cotellic)?

Vemurafenib is a BRAF (pronounced bee-raff) inhibitor, and cobimetinib is a MEK (pronounced meck) inhibitor. Each medication:

  • Is a type of targeted therapy known as signal transduction inhibitors
  • Helps slow or stop the growth and spread of melanoma cells

Learn more about vemurafenib (Zelboraf) as a single drug.

How Do Vemurafenib and Cobimetinib Work Together?

Vemurafenib blocks the activity of a mutated form of a molecule called BRAF. Cobimetinib blocks the activity of a molecule called MEK. BRAF and MEK are protein molecules that are important in regulating cell growth.

The BRAF V600E and V600K mutations signal cells to grow abnormally and divide out of control. These cells can become a melanoma tumor. About half of all melanomas have a BRAF mutation.

MEK receives signals from BRAF and other molecules in the cell. In melanoma treatment, researchers have found that blocking BRAF and MEK at the same time is more effective than blocking MEK alone.

The combination of vemurafenib and cobimetinib interferes with abnormal BRAF signals to slow or stop the out-of-control cell growth:

  • Vemurafenib blocks the signaling pathway of the V600E-mutated BRAF molecule.
  • Cobimetinib blocks signaling from the V600E- or V600K-mutated BRAF molecule via the MEK molecule.

Which Patients May Benefit from Vemurafenib and Cobimetinib?

In 2015, the U.S. Food and Drug Administration (FDA) approved the use of cobimetinib only in combination with vemurafenib to treat patients who have advanced stages of melanoma:

  • Stage III that is unresectable (unable to be completely removed by surgery)
  • Stage IV, also known as metastatic (melanoma cells that have spread to organs and other parts of the body)

This combination therapy works only in patients whose melanoma has tested positive for the BRAF V600E or V600K mutation. If you have advanced melanoma, your physician will test you for specific genetic mutations before prescribing this medication combination. The physician will send a biopsy (sample of cancer tissue from your body) to a special lab for analysis.

How Are Vemurafenib and Cobimetinib Given?

Patients take both medications orally (swallowing by mouth).

  • The recommended dose for vemurafenib is 960 mg twice each day, via 240 mg tablets.
  • The recommended dose for cobimetinib is 60 mg once each day.
  • Depending on how you respond to treatment, your physician may adjust your doses.
  • Patients usually continue to take these medications for a period of time, until their melanoma worsens or they experience unacceptable side effects. 

What Are the Goals of Vemurafenib and Cobimetinib?

The combination of vemurafenib and cobimetinib targets specific molecules that regulate cancer cell growth, with the goals of:

  • Slowing the growth or spread of melanoma
  • Shrinking melanoma tumors
  • Helping patients live longer

Results from a Phase III clinical trial in 2015 showed improved patient outcomes for patients taking vemurafenib and cobimetinib compared with patients taking vemurafenib alone.

Melanoma treatments, like vemurafenib and cobimetinib, have side effects, which can sometimes be serious. Patients should talk with their physician to learn more about the side effects of these and other melanoma treatment options.

What Should I Ask My Doctor About Vemurafenib and Cobimetinib?

Because everyone is different, not all treatments work for all patients with melanoma. If you are interested in learning more about the combination of vemurafenib and cobimetinib, here are some questions you should ask your physician:

  • Will my melanoma tumor be tested for BRAF genetic mutations?
  • Am I eligible for vemurafenib and cobimetinib?
  • What is your experience with vemurafenib and cobimetinib?
  • Is this combination therapy a good option for my melanoma treatment?
  • Is there an alternative to vemurafenib and cobimetinib for me?
  • How successful has the combination been for patients like me?
  • What are the side effects of this combination?
  • Are there any clinical trials for the combination therapy that I should consider?
  • What other treatments are FDA-approved for treating advanced melanoma?
  • What are the risks and benefits of the available treatment options?
  • What are the goals for my treatment?
  • How long will I stay on this treatment?

Need Help Paying for Vemurafenib (Zelboraf) + Cobimetinib (Cotellic)?

Patient Assistant Programs (PAPs) are designed so that you still have access to the treatments you need, in any financial circumstance. Learn more about the manufacturer’s patient assistance program and other options here.

Manufacturer’s Patient Assistance


Latest Treatments for Advanced Melanoma

Learn more about the latest, most effective treatments for patients who have advanced melanoma:

Melanoma Research

The Melanoma Research Alliance is the largest, non-profit funder of melanoma research worldwide. Since 2007, we have directly funded over $131 million in innovative grants to improve prevention, detection, and treatment of melanoma. We have also leveraged an additional $415 million in outside funds for research. Learn more about our funded research.

Last updated: August, 2021