General Information

Kimmtrak (tebentafusp-tebn) is a bispecific gp100 peptide-HLA-directed CD3 T cell engager.

Kimmtrak is specifically indicated for the treatment of HLA-A*02:01-positive adult patients with unresectable or metastatic uveal melanoma.

Kimmtrak is supplied as an injection for intravenous administration. The recommended dosage is 20 mcg intravenously on Day 1, 30 mcg intravenously on Day 8, 68 mcg intravenously on Day 15, and 68 mcg intravenously once every week thereafter. Dilute and administer by intravenous infusion over 15-20 minutes.

Mechanism of Action

Kimmtrak (tebentafusp-tebn) is a bispecific gp100 peptide-HLA-directed CD3 T cell engager. The TCR arm binds to a gp100 peptide presented by human leukocyte antigen-A*02:01 (HLAA*02:01) on the cell surface of uveal melanoma tumor cells. In vitro, tebentafusp-tebn bound to HLA-A*02:01-positive uveal melanoma cells and activated polyclonal T cells to release inflammatory cytokines and cytolytic proteins, which results in direct lysis of uveal melanoma tumor cells.

Side Effects

Adverse effects associated with the use of Kimmtrak may include, but are not limited to, the following:

• cytokine release syndrome
• rash
• pyrexia
• pruritus
• fatigue
• nausea
• chills
• abdominal pain
• edema
• hypotension
• dry skin
• headache
• vomiting
• laboratory abnormalities, including decreased lymphocyte count, increased creatinine, increased glucose, increased aspartate aminotransferase, increased alanine aminotransferase, decreased hemoglobin, and decreased phosphate

The Kimmtrak drug label comes with the following Black Box Warning: Cytokine Release Syndrome (CRS), which may be serious or life threatening, occurred in patients receiving Kimmtrak. Monitor for at least 16 hours following first three infusions and then as clinically indicated.

Clinical Trial Results

The approval of Kimmtrak was based on the results of Immunocore’s Phase 3 IMCgp100-202 clinical trial. The randomized pivotal trial evaluated overall survival (OS) of Kimmtrak compared to investigator’s choice (either pembrolizumab, ipilimumab, or dacarbazine) in patients with previously untreated mUM. 378 patients were randomized in a 2:1 ratio to either Kimmtrak or investigator’s choice. Data from the trial showed that Kimmtrak demonstrated unprecedented median OS benefit as a first-line treatment. The OS Hazard Ratio (HR) in the intent-to-treat population favored Kimmtrak, HR=0.51 (95% CI: 0.37, 0.71); p< 0.0001, over investigator’s choice (82% pembrolizumab; 13% ipilimumab; 6% dacarbazine). In the clinical trials, across both arms, patients stopped treatment for disease progression, unless the patient was otherwise deriving benefit, or for unacceptable toxicity.