Shares of Celldex Therapeutics (CLDX) surged as much as 30% today after the company disclosed that it achieved positive results in patients with recurrent brain cancer in an interim phase 2 analysis. The phase 2 study, known as the REACT study, uses the company’s drug known as Rindopepimut to target patients with recurrent Glioblastoma — brain cancer — that have the EFGRvIII gene. These types of patients with this form of brain cancer gene fare worse than most other Glioblastoma patients. Not only that, but these patients in the study were previously treated with a popular cancer drug from Roche known as Avastin and these patients became resistant to the Avastin treatment. This means that Avastin had failed to halt or treat the progression of these patients’ cancers. 

The REACT trial was testing Rindopepimut — Celldex’s drug — together with Avastin against Avastin alone with control in recurrent brain cancer patients.The company reported that the interim data showed that the REACT trial achieved its primary endpoint of PFS — Progression Free Survival — with Rindopepimut achieving a 27% rate versus the control group obtaining an 11% rate. Progression-free survival is the amount of time a patient advances into the trial without their cancer worsening. This means that the Rindopepimut plus Avastin group fared much better than the Avastin with control group.

The Rindopepimut plus Avastin group also saw a nice increase in overall survival. Overall survival is the length of time a patient can live while taking the company’s drug compared to the control group. Rindopepimut saw an overall survival of 12 months compared to the control group only obtaining roughly 9 months. That means that this cancer drug extended patients’ lives as well. We believe that Celldex Therapeutics is a great long term buy candidate as its main cancer drug compound is now de-risked. The company has a big pipeline of other compounds that could eventually keep the share price momentum heading up in the coming months.