Combination treatment fails to improve survival in recurrent glioma

Reuters Health - 04/11/2020 - Following tumor resection in patients with recurrent glioblastoma and anaplastic astrocytoma, treatment with vocimagene amiretrorepvec (Toca 511) and with flucytosine (Toca FC) provides no improvement in overall survival, according to an open-label phase 2/3 trial.

"Unfortunately," Dr. Michael A. Vogelbaum told Reuters Health by email, "glioblastoma remains a highly aggressive form of cancer with few effective therapies. The same was the case for decades for multiple other forms of cancers that we now consider to be routinely treatable, and we will continue to pursue new strategies."

The standard of care for these aggressive brain tumors involves maximal safe resection plus radiotherapy and concurrent chemotherapy with temozolomide followed by temozolomide maintenance therapy, Dr. Vogelbaum of the H. Lee Moffitt Center, in Tampa, Florida, and colleagues note in JAMA Oncology.

But nearly all high-grade gliomas eventually recur, with a median overall survival ranging from 7.1 to 9.8 months for recurrent glioblastoma.

To determine whether Toca 511 and Toca FC might be of help, the researchers studied 403 patients who received tumor resection for first or second recurrence of glioblastoma or anaplastic astrocytoma.

The participants were randomized to receive Toca 511 injected into the resection cavity wall at the time of surgery followed by cycles of oral Toca FC or to a standard-of-care control group. The control patients received the investigator's choice of single therapy with lomustine, temozolomide or bevacizumab.

Follow-up lasted a median 22.8 months. Median overall survival was 11.10 months in the Toca 511/FC group and 12.22 months in the control group. Adverse events were similar between groups and there were no significant differences in other outcome measures.

The results of this study, the researchers conclude, "may help to inform future study designs including population selection and minimum number of Toca FC treatment cycles."

The study was sponsored and funded by Tocagen Inc, which developed Toca 511 and Toca FC.

By David Douglas

SOURCE: https://bit.ly/3kW9kTI JAMA Oncology, online October 29, 2020.



Posted on 4 November 202020 November 2020