Tocagen shares collapse as investigators read last rites for PhIII brain cancer study
Two years after going public on the promise of a new approach to fight recurrent brain cancer, Tocagen has hit the wall.
The biotech bluntly reported the failure of their pivotal Phase III study of a 2-part drug — Toca 511 & Toca FC — for high-grade glioma. Part 1 uses a vector to attack cancer cells in the brain and deliver a gene for an enzyme, while part 2 is a prodrug — 5-fluorocytosine (5-FC) — that converts into the anti-cancer therapy 5-FU.
It didn’t work.
Researchers at the San Diego-based biotech reported that they hit a hazard ratio of 1.06, reflecting an increased risk to patients, with a disastrous p-value of 0.6154. The overall survival rate for the drug arm hit 11.1 months compared to 12.2 months for control.
The company says it will now thoroughly analyze the data, but investors weren’t waiting around. The stock $TOCA for the micro-cap biotech was blitzed, nose-diving 81% ahead of the bell.
Brain cancer has been one of the toughest fields in oncology, with a slew of failures reported out. Tocagen has two other programs underway for the same tech, but they are both very early stage studies.