Skip to main content

Tocagen enrol patients in Toca 5 phase 2/3 trial in South Korea to treat recurrent brain cancer

 

Clinical courses

Tocagen Inc., a clinical-stage, cancer-selective gene therapy company, announced its randomized, controlled phase 2/3 clinical trial, called Toca 5, is now enrolling patients in South Korea. The trial is ongoing in the United States, Canada and Israel. The study compares a cancer-selective virus, Toca 511 (vocimagene amiretrorepvec), in combination with Toca FC (extended-release 5-fluorocytosine), to standard of care in patients with first or second recurrence of glioblastoma or anaplastic astrocytoma who are undergoing resection.

“Brain tumours are among the deadliest of all cancers and there are very few treatment options available,” said Do Hyun Nam, M.D., professor, department of neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, which enrolled the first patient in South Korea. “Data from phase 1 studies of this investigational agent showed very promising safety, survival and durable tumour response data so we are excited to continue evaluation of this therapy in the Toca 5 trial.”

Sin-Soo Jeun, M.D., professor of neurosurgery at Seoul St. Mary’s Hospital, is the principal investigator for the Toca 5 clinical trial in South Korea.

The primary endpoint for the Toca 5 clinical trial is overall survival with secondary endpoints including objective response rate. Investigators may choose chemotherapy (lomustine or temozolomide) or antiangiogenic therapy (bevacizumab) for the control arm.

 

A total of 126 patients have been treated in Tocagen’s phase 1, ascending-dose studies. Clinical data were recently published in Science Translational Medicine. In the subset of patients in the higher dose cohorts that mirror the patient population under evaluation in the ongoing Toca 5 trial, a clinical benefit rate of 41.7% was reported at the 21st Annual Scientific Meeting and Education Day of the Society for Neuro-Oncology. This included 3 complete responses, 2 partial responses and 5 patients with stable disease (N=24). All patients with an objective response remain alive and in response. The median duration of response is at least 26.7 months.

Tocagen’s lead product candidate is a combination of an investigational biologic, Toca 511, and an investigational oral tablet, Toca FC. Toca 511 encodes a prodrug activator enzyme, CD. Its selective delivery to cancer cells means that the infected cancer cells carry the CD gene and produce CD protein. Toca FC is an orally administered, proprietary extended-release formulation of 5-fluorocytosine (5-FC), a prodrug that is inactive as an anti-cancer drug. Within Toca-511-infected cancer cells that are producing CD, Toca 511 is designed to convert Toca FC into the anti-cancer drug, 5-fluorouracil (5-FU) at local high concentrations. In addition to the direct killing of Toca 511-infected cancer cells, 5-FU kills neighbouring uninfected cancer cells and immunosuppressive myeloid cells including myeloid derived suppressor cells (MDSCs) and tumour associated macrophages (TAM) in the tumor.

<< Pharma News

Subscribe to PharmaTutor News Alerts by Email