Injectable immunotherapy shows promise for liver tumors

Talimogene laherparevec, a genetically modified version of the herpes virus, was well-tolerated after injection into active cancer in the liver and stimulated patient immune systems to destroy cancer cells throughout the body, according to a press release and presentation at the Society of Interventional Radiology Annual Scientific Meeting.

“Advanced stage liver tumors, including ones that have spread from other locations, have limited treatment options because the patients can be in poor health; further, the complex structure of the organ can make it difficult to target with standard approaches,” Steven S. Raman, MD, from the David Geffen School of Medicine, University of California, and lead study author said in the press release. “This minimally invasive treatment offers patients a novel way to directly and indirectly attack the cancer cells.”

Talimogene laherparevec (T-VEC, Amgen) is a genetically modified HSV-1 oncolytic immunotherapy designed to preferentially replicate in tumors and produce granulocyte-macrophage colony-stimulating factor to stimulate anti-tumor immune responses.

Fourteen patients with either hepatocellular carcinoma or liver metastases related to extrahepatic cancer received T-VEC every 21 days up to the maximum tolerated concentration of 10⁸ plague-forming units per mL.

One patient underwent liver transplantation and three patients had a significant increase in aspartate aminotransferase and bilirubin after one dose. Four patients had grade 3 or 4 treatment-related adverse events. Two patients died and both were attributable to disease.

The researchers deemed the intralesional injection of T-VEC as tolerable and feasible in patients with liver cancer and metastases. They further report planning an additional investigation in combination with a PD-1 inhibitor.

“Image-guided treatments have expanded the options available for patients with liver cancer from innovative approaches to biopsies to resections to chemo,” Raman said in the release. “This is an exciting way to look to the future, but patients living with advanced liver cancer should understand that this treatment will not be available for several years, except through clinical trials.” – by Talitha Bennett

Reference: Raman SS. Abstract 375. Presented at: Society of Interventional Radiology Annual Scientific Meeting; Mar. 17-22, 2018; Los Angeles.

Disclosure: The authors report that the pharmaceutical manufacturer of T-VEC, Amgen, was a sponsor of the trial.