FDA Approves Pepaxto® (melphalan flufenamide) Combo for Triple-Refractory Myeloma

Editor’s Note: As of October 22, 2021, Pepaxto was withdrawn from the market in the United States. More information about this can be found here.

The U.S. Food and Drug Administration (FDA) has granted accelerated approval for Pepaxto^® (melphalan flufenamide) given with dexamethasone for multiple myeloma.¹

Pepaxto is approved for use in adults who have tried at least 4 other treatments that no longer work for their multiple myeloma. These treatments include at least:^1,2

• 1 proteasome inhibitor
• 1 immunomodulatory agent
• 1 CD38-directed monoclonal antibody

Multiple myeloma is a rare disease that currently has no cure. The FDA may give accelerated approval to new drugs that treat a health condition with few or no other treatments. This means drugs like Pepaxto can be sold sooner.²

What are the ingredients in Pepaxto?

The active ingredient in Pepaxto is melphalan flufenamide. Pepaxto is also known as melflufen.²

How does the it work?

Pepaxto is a peptide-drug conjugate. A peptide is a protein chain that can link to a drug. A conjugate is a way to fuse a peptide and melphalan. Inside a cancer cell, this fusion is rapidly broken. This break releases melphalan into the cancer cell and allows it to treat multiple myeloma.²

Evidence for Pepaxto

Pepaxto was granted accelerated approval based on the results of the Horizon Phase 2 clinical trial. In this trial, 157 adults were given Pepaxto with dexamethasone as treatment for multiple myeloma.^1,2

A group of 97 adults had a 23.7 percent overall response rate with this combination. This means their cancer shrank or disappeared after treatment with Pepaxto. Some people maintained this response for roughly 4 months.¹

What are the possible side effects?

The most common side effects of Pepaxto include:^1-3

• Fatigue
• Nausea
• Diarrhea
• Fever
• Respiratory tract infection
• Low red and white blood cell counts
• Low platelet counts
• Kidney problems

Pepaxto can cause bone marrow suppression (myelosuppression). This is a decrease in bone marrow activity that causes the body to make fewer blood cells. Contact your doctor immediately if you have any of the following symptoms:³

• Bleeding and easy bruising
• Signs of infection, including fever, chills, cough, pain, or burning during urination
• Fatigue
• Shortness of breath

These are not all the possible side effects of Pepaxto. Talk to your doctor about what to expect or if you experience any changes that concern you during treatment with Pepaxto.

Things to know

If you are allergic to melphalan or Pepaxto, you should not use Pepaxto.^3,4

Your doctor will monitor your platelet, red blood cell, and white blood cell levels before and as needed during treatment with Pepaxto.³

Pepaxto can harm an unborn baby. Women who can become pregnant and men with partners who can become pregnant should use birth control during treatment and for some time after the last dose of Pepaxto. Women should also not breastfeed during treatment with Pepaxto and for some time after the last dose. Talk to your doctor about your options for birth control and breastfeeding while taking Pepaxto.^3,4

Before beginning treatment for multiple myeloma, tell your doctor about all your health conditions and any other drugs, vitamins, or supplements you are taking. This includes over-the-counter drugs.

For more information, read the full prescribing information of Pepaxto.