Celldex Stock Chokes as Brain Cancer Trial Halted
Published: Mar 08, 2016
March 7, 2016
By Mark Terry, BioSpace.com Breaking News Staff
Hampton, N.J.-based Celldex Therapeutics announced today that its Rintega cancer vaccine had failed to meet its primary endpoint and the study was being terminated. The company’s shares plunged by more than half in premarket trading on the news.
An independent Data Safety and Monitoring Board (DSMB) determined that the study should be halted based on interim analysis of data from the Phase III, ACT IV study. Rintega (rindopepimut) is a cancer vaccine designed to focus the immune system on a specific tumor type, in this case, in patients with newly diagnosed EGFRviii-positive glioblastoma (GMB), a type of brain cancer.
GMB is the most prevalent and aggressive form of brain cancer, and according to the National Cancer Institute about 22,850 new cases were diagnosed in the U.S. in 2015. There were an estimated 15,320 related deaths. Fewer than 10 percent of patients who have glioblastoma recurrence live more than five years.
The DSMB’s analysis found that Rintega cut the risk of death by only 1 percent compared to the control arm of the study. But the median range was worse—patients on Rintega only survived 20.4 months compared to 21.1 months in the control arm.
“We are extremely disappointed for patients that the ACT IV study was not successful,” said Anthony Marucci, Celldex co-founder, president and chief executive officer, in a statement. “On behalf of Celldex, I want to express our gratitude to the ACT IV investigators, patients and families who participated in this trial. While this is certainly not the desired outcome, we remain steadfast believers in the power of immunotherapy to transform the future of cancer treatments.”
Patients who were receiving Rintega will be offered the drug on a compassionate use basis.
Celldex’s have had a rough year in general. Shares traded a year ago, on March 19, 2015, for $31.78. On Aug. 21, they traded for $13.53, then dropped to $10.38 on Sept. 29. Shares rebounded a bit on Nov. 23 to $18.11, then dropped on Feb. 10, 2016 to $6.45. Shares are currently trading for $8.19.
Celldex has a fairly vigorous pipeline. Its glembatumumab vedotin is an antibody drug conjugate being studied in a trial on triple-negative breast cancer patients. Enrollment for patients is expected to be completed in the second half of this year. The company’s varlilumab, a monoclonal antibody that targets CD27, is being investigated in early clinical trials in solid tumors, some in conjunction with Bristol-Myers Squibb’s checkpoint inhibitor, Opdivo.
Although the idea of a cancer vaccine is intriguing, there hasn’t been many successes to date. ImmunoCellular Therapeutics’s GBM vaccine ICT-107 failed trials in 2013. A GBM vaccine called DCVax, developed by Northwest Biotherapeutics , was halted in August for unexplained reasons.
So far Provenge, a vaccine for prostate cancer, is the only approved cancer vaccine, although Dendreon declared bankruptcy and was acquired by Valeant Pharmaceuticals . Provenge was considered a very promising drug, but its price tag was $93,000 for a course of treatment. Physicians didn’t pick it up and insurers were reluctant to pay for it.
"Dendreon combined undue optimism in sales projections with excessive risk in its capital structure,” said Erik Gordon, professor at the University of Michigan’s Ross School of Business in a statement from Feb. 2015. “It is a case of moderate product success and immoderate management failure.”
Although not always cited as a cancer vaccine, the vaccines against human papilloma virus (HPV) are actually vaccines against certain types of cancer, including cervical cancer, anal cancer, vaginal cancer, vulvar cancer and some types of mouth cancer. Gardisil is marketed by Merck , and Cervarix is marketed by GlaxoSmithKline .