Northwest Bio unveiled interim phase 3 data showing its dendritic cell vaccine improved survival rates in patients with newly diagnosed glioblastoma, in some cases even doubling survival. Northwest's stock shot up 35% on the news, but its Tuesday high of $0.31 still puts the biotech in penny-stock territory, and promptly fell about 10% after-hours.
The data, published in the Journal of Translational Medicine, are blinded and include patients from both the treatment and placebo arms of the trial. The 331 patients were randomized such that two-thirds of them received standard of care—surgical resection, followed by chemo and radiotherapy—and Northwest's vaccine, DCVax-L, with the remaining one-third receiving standard of care and placebo. However, about 90% of the trial participants ended up receiving DCVax-L, as those who experienced tumor recurrence could "cross over" into the treatment arm and receive the vaccine without knowing which arm they had been in previously. Both patients and investigators remain blinded as the trial continues.
The median survival for the combined arms of the trial was 23.1 months from surgery, while this number was 34.7 for patients with a methylated MGMT gene, a marker that predicts responsiveness to alkylating chemotherapy, such as temozolomide. Patients with unmethylated MGMT had a median survival of 19.8 months from surgery, which is still greater than the median survival rate with the standard of care: 15 to 16 months.
The top 30% of patients did even better, logging 40.5 months of survival after surgery. But Northwest is unsure what contributed to this: "This extended survival was not fully explained by known prognostic factors such as age younger than 50 years, methylated MGMT gene status and complete resection (surgical removal) of all of the tumor. Only 8% of these 100 patients had the favorable status on all 3 of these prognostic factors," it said in a statement.
The data also suggest that once patients got "over the hump," or past a certain time point, they were likely to "have continued onwards to substantially extended survival." The study had a low incidence of serious adverse events—2%—and the overall adverse events rate was on par with that of the standard of care.
"These are just interim data, and the data may get either better or worse as they continue to mature," said Northwest Bio CEO Linda Powers in the statement. "However, the survival times we are seeing are encouraging, especially in light of how little progress has been made in decades in treatments for glioblastoma."
Glioblastoma is the most aggressive form of brain cancer and is notoriously difficult to treat, thanks to the blood-brain barrier and the heterogeneity of its tumor cells. Northwest's DCVax platform is designed to target multiple biomarkers on an individual patient's tumor. It is made by removing monocytes from the patient via blood draw. The monocytes are then differentiated into dendritic cells, which are then "activated" and combined with antigens from the patient's own tumor. The treated cells are then injected back into the patient, where they will recognize and attack the cancer.
The DCVax-L trial was first registered in 2002, so Northwest's shareholders have been waiting a while for these data. So long that a shareholder even asked in 2017: Where’s the phase 3 data for your leading cancer vax candidate DCVax? The company's answer, made public in an SEC filing, was unsatisfying, saying that it had some of the data but not all from this test before it shut down for the Christmas holidays. And the company was unable to pick right back up after the holidays as its "key management" had been hit with "a major case of the flu."