A Two-part Protein to Treat Uveal Melanoma 

The FDA approved the targeted immunotherapy tebentafusp-tebn for certain adult patients with uveal melanoma. 

The U.S. Food and Drug Administration (FDA) has approved tebentafusp-tebn (Kimmtrak), a fusion protein that acts as an immunotherapy, for the treatment of some adult patients with unresectable or metastatic uveal melanoma, a type of cancer found in the eye. 

Tebentafusp-tebn is a two-part protein that acts as a tether between cancer cells and a type of immune cell known as T cells. One part of the protein recognizes the peptide gp100, expressed in uveal melanoma cells and presented on the cell surface by a protein called HLA-A*02:01. The other part of the protein binds to the receptor CD3 on T cells and activates the T cells to fight the cancer. 

Because HLA-A*02:01 is required for gp100 presentation but is one of many HLA proteins humans can inherit, tebentafusp-tebn is recommended only for patients with the HLA-A*02:01 gene. 

The efficacy of this treatment was evaluated in an open-label, multicenter clinical trial in which 378 patients were randomly assigned to receive tebentafusp-tebn or a standard-of-care drug chosen by the investigator. Patients receiving tebentafusp-tebn survived for a median of 21.7 months, compared with 16 months among patients treated with investigator’s choice drugs. These clinical trial data were presented at the AACR Annual Meeting 2021, and data from a phase I/II trial of tebentafusp-tebn were published in Clinical Cancer Research, a journal of the American Association for Cancer Research (AACR). 

Uveal melanoma, also called intraocular melanoma, is a rare cancer that develops in the middle layer of the eye. According to the National Cancer Institute, the mean age-adjusted incidence of uveal melanoma in the U.S. is 4.3 new cases per 1 million people. 

The FDA rendered its approval on January 25, 2022.