The U.S. Food and Drug Administration (FDA) has granted breakthrough therapy designation to Immunocore‘s tebentafusp (IMCgp100) for HLA-A2 positive, inoperable, or advanced uveal melanoma — a common and difficult-to-treat form of eye cancer — the company announced in a press release.
The breakthrough therapy status was awarded after a Phase 3 trial showed that tebentafusp worked better than currently available treatments in extending survival in certain newly diagnosed uveal melanoma patients.
This designation is given to accelerate the development, review, and possible approval of medications for serious or life-threatening conditions that have the potential to provide significant advantages over current treatments.
Tebentafusp is a bispecific antibody comprising two parts. One is designed to specifically target gp100, a protein highly present in melanoma cells, while the other binds to CD3, a protein receptor found on the surface of immune T-cells. Together, they work to bring immune cells closer to cancer cells, facilitating the death of the cancer cells.
The FDA’s decision was based on interim data from the IMCgp100-202 Phase 3 trial (NCT03070392), which showed that tebentafusp is superior to other therapies at extending survival in adults with newly diagnosed metastatic uveal melanoma.
The trial included a total of 378 participants, who were randomly assigned to either first-line tebentafusp or a treatment selected by the investigators (the control group). The majority of patients in the investigator’s choice group received the immune checkpoint inhibitors Keytruda (82%) or Yervoy (12%), while the remaining participants were given the chemotherapy dacarbazine (6%).
With patients on tebentafusp showing a 49% lower risk of death than those given other therapies, the study’s primary goal of overall survival was met. Additionally, after one year in the trial, more patients on tebentafusp were alive than those in the control group (73% vs. 58%).
“We are delighted that the FDA has granted Breakthrough Therapy Designation for tebentafusp based on the survival benefit from our Phase 3 clinical trial announced in November 2020,” said Bahija Jallal, CEO of Immunocore.
Immunocore now plans to submit a biologics license application to the FDA seeking the approval of tebentafusp for metastatic uveal melanoma. If approved, it will be the first new treatment for this indication in 40 years, according to the biotechnology company.
“There is an urgent need for an approved treatment for this rare and aggressive form of melanoma and we look forward to continuing to work with regulators to bring tebentafusp to patients as quickly as possible,” said Jallal.
Tebentafusp was previously granted orphan drug and fast track status by the FDA to treat uveal melanoma. Both designations are aimed at accelerating a therapy’s clinical development and review.
In addition, the therapy received the promising innovative medicine designation by the U.K.’s Medicines and Healthcare products Regulatory Agency for the same disease, making it a potential candidate for an early access program before its approval.
