ZIOPHARM Oncology Inc. (NASDAQ:ZIOP) announced updated results from its Phase 1 multicenter study of Ad-RTS-hIL-12 + veledimex including the 20 mg expansion cohort in patients with recurrent or progressive glioblastoma (GBM) at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting June 2-6 in Chicago.

In a poster presentation titled “Expanded phase I study of intratumoral Ad-RTS-hIL-12 + oral veledimex: tolerability and survival in recurrent glioblastoma,” the Company reported results from 25 patients with recurrent or progressive Grade III or IV glioma enrolled in three veledimex dosing cohorts (20 mg, n = 15; 30 mg, n = 4; and 40 mg, n = 6). Subjects with recurrent or progressive Grade III or IV glioma undergoing resection were injected intratumorally with Ad 2 x 1011 viral particles and received daily oral activator veledimex for 15 doses.

As of May 24, 2017, the cutoff date for the ASCO presentation, median overall survival (mOS) of all patients receiving intratumoral Ad-RTS-hIL-12 with 20 mg of orally-administered veledimex was maintained at 12.5 months, with a mean follow-up time of 9.2 months. The majority of patients in the 20 mg cohort had 2 or more recurrences prior to entry in the study, indicating very advanced disease.

“With the ability to control and turn IL-12 expression on and off from within the brain tumor, Ad-RTS-hIL-12 + veledimex offers the potential to safely direct one of the most potent anti-cancer immune cytokines against one of the most aggressive and lethal cancers,” said E. Antonio Chiocca, MD, PhD, Harvey W. Cushing Professor of Neurosurgery, Department of Surgery, Harvard Medical School, Surgical Director, Center for Neuro-oncology, Dana-Farber Cancer Institute, Chairman, Neurosurgery, Brigham and Women’s Hospital and Co-Director, Institute for the Neurosciences, Brigham and Women’s Hospital.

Dr. Chiocca added, “These data suggest that intra-tumor expression of IL-12 is well tolerated by patients with recurrent glioblastoma. There are also highly encouraging observations that activation of the immune system in the patients may result in anti-tumor effects. I look forward to understanding Ad-RTS-IL-12 + veledimex’s full potential in this challenging disease in a larger study.”

Based on the ratio of CD8+/FOXP3+ (effector/suppressor) T cells measured in peripheral blood 14 to 28 days after viral injection, survival appears correlated with IL-12-mediated cellular immune activation. Consistent with this observation, steroid use in the first 15 days after injection of the virus appears to have a deleterious effect on patient survival, presumably due to interference with immune activation. Drug-related toxicities, which were primarily non-neurologic, showed a dose response to veledimex, were consistent with those previously reported, and importantly, continue to be reversed upon cessation of the activator ligand, with no drug-related deaths. As previously reported, a strong, dose-dependent correlation between veledimex dose, veledimex blood brain barrier penetration, IL-12 and IFN-gamma production was also observed.

“We are now seeing a correlation between survival and cellular immune modulation, in addition to maintenance of the survival benefit in the expanded 20 mg veledimex dose cohort,” said Francois Lebel, M.D., Executive Vice President, Research and Development, Chief Medical Officer at ZIOPHARM. “We have uncovered that the effects of an IL-12-driven immune activation is dampened by the concurrent use of high-dose steroids. This is reflected in the survival of the patients, where patients who received less than 10 mg of dexamethasone have a much better survival than those on elevated systemic steroids. We are excited about Ad-RTS-hIL-12 + veledimex moving into a pivotal study this year, following completion of our discussions with regulators.”

Shares of Ziopharm are currently trading at $5.87, down $0.16¬†or -2.65%. ZIOP has a 1-year high of $7.88 and a 1-year low of $4.45. The stock’s 50-day moving average is $6.92 and its 200-day moving average is $6.43.

On the ratings front, Ziopharm has been the subject of a number of recent research reports. In a report issued on June 1, H.C. Wainwright analyst Swayampakula Ramakanth initiated coverage with a Buy rating on ZIOP and a price target of $9.50, which represents a potential upside of 58% from where the stock is currently trading. Separately, on February 27, Griffin Securities’ Keith Markey reiterated a Buy rating on the stock and has a price target of $23.

According to TipRanks.com, which ranks over 7,500 financial analysts and bloggers to gauge the performance of their past recommendations, Swayampakula Ramakanth and Keith Markey have a yearly average loss of 17.5% and 32.9% respectively. Ramakanth has a success rate of 25% and is ranked #4516 out of 4579 analysts, while Markey has a success rate of 10% and is ranked #4504.

ZIOPHARM Oncology, Inc. is a biopharmaceutical company currently in developmental stage that seeks to acquire, develop and commercialize, on its own or with commercial partners, a diverse portfolio of cancer therapies. It is focused on two clinical stage product candidates: Ad-RTS-IL-12 + veledimex and DC-RTS-IL-12 + veledimex.