Telomelysin (OBP-301) is an anticancer treatment being developed by Oncolys BioPharma as a new cancer immunotherapy. It is currently being tested in clinical trials for people with melanoma (an aggressive form of skin cancer), liver cancer, and cancer of the esophagus.

Immunotherapies stimulate the body’s own immune system to fight cancer instead of directly attacking cancer cells.

How Telomelysin works

Telomelysin is a cancer vaccine, a type of cancer treatment that both treats and prevents cancer by using the body’s own immune system to attack and kill cancer cells.

The vaccine consists of a virus that was genetically modified in the laboratory to have the ability to multiply inside cancer cells. When it is injected into the body, the virus enters cancer cells and multiplies inside them, which causes tumor cells to burst. This virus does not infect or multiply in healthy cells.

Telomelysin in clinical trials

In preclinical studies, Telomelysin showed anticancer activity in several cancers without safety or toxicity concerns, Oncolys BioPharma said.

Results from the first Phase 1 clinical trial of Telomelysin in solid tumors showed promise, with tumor reduction observed in eight of the 12 patients treated. Adverse effects were mostly mild to moderate, and transitory.

A phase 1 clinical trial (NCT03213054) is ongoing in Japan to test Telomelysin in combination with radiotherapy in esophageal cancer. The study started in July 2017 after encouraging initial results from a similar study, also conducted in Japan, that showed that four out of seven treated patients showed a complete response.

Additionally, a Phase 1/2 clinical trial (NCT02293850) is being conducted in South Korea and Taiwan to investigate Telomelysin in patients with liver cancer who are resistant to existing cancer treatments. The study started in November 2014 and is still recruiting participants. According to the company, nine patients have been included to date, and initial results showed effectiveness in two patients and prolonged stable disease in one patient. They also showed that Telomelysin was safe when injected directly into the liver.

Next steps for Telomelysin

Oncolys BioPharma plans to initiate two more clinical studies to test Telomelysin, in melanoma patients and in esophageal cancer patients. The melanoma study will take place in the U.S. and aims to dose the first patient in 2017. The esophagus cancer study will test Telomelysin in combination with another type of immunotherapy called a checkpoint inhibitor.


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