Image source: NewLink Genetics.
Pancreatic cancer is one of the toughest-to-treat cancers and there's a significant need for innovation in how we battle the disease. Fortunately, considerable research is ongoing that is evaluating combining various treatments together to improve overall survival. This week, NewLink Genetics Corporation (NLNK) reported that one of those studies evaluating the addition of its algenpantucel-L vaccine to chemotherapy and chemoradiotherapy regimens is now fully enrolled. Let's learn more about it.
Improving outcomes
Despite advances in the use of chemotherapy and chemoradiotherapy in pancreatic cancer patients, surgery remains the only curative therapy for pancreatic cancer and the median overall survival rate for pancreatic cancer patients remains about 20 months. Because of this, a similar number of people pass away from this disease as are diagnosed annually.
Fortunately, projects are underway that may improve patient outcomes, including NewLink Genetics phase 3 Impress trial that's studying algenpantucel-L as an adjunct to gemcitabine plus Abraxane, or FOLFIRINOX treatment regimens, which are the standard of care.
Algenpantucel-L is a vaccine that is crafted from two pancreatic cancer cell lines that are genetically modified to express alpha-Gal, a mouse gene that is targeted and destroyed by a patient's immune system. Once the immune system destroys those alpha-Gal containing cells, it processes their remnants and because those remnants include specific antigens that are shared by the patient's pancreatic cancer cells, the immune system becomes better educated on how to find and destroy the cancer.
Image source: Aduro BioTech.
This approach delivered encouraging efficacy during previous trials, including a one-year overall survival rate of 86% when used alongside chemotherapy and chemoradiology. Those results essentially match up to those from a study by competitor Aduro BioTech (ADRO) for its GVAX Pancreas vaccine as an adjunct to FOLFIRINOX and chemoradiation. Instead of expressing alpha-Gal, GVAX Pancreas engineers pancreatic cancer cell lines to secrete large levels of GM-CSF to invoke an immune system response. In Aduro BioTech's trials, the median 1-year overall survival rate was 85%.
Looking forward
There's no guarantee that promising mid-stage results for NewLink Genetics pancreatic cancer vaccine will be confirmed by the now fully enrolled phase 3 study. Historically, up to 40% of phase 3 trials end up failing and those failures can be caused by lackluster efficacy or safety risks that emerge once drugs are used in larger patient populations.
However, if NewLink Genetics results do confirm its prior findings and the therapy is found to be safe, then the company may have an advantage over Aduro BioTech because Aduro BioTech recently reported that a patient developed a dangerous listeria infection after receiving GVAX Pancreas and Aduro BioTech's CRS-207, a listeria-based drug that boosts a body's immune system response. Although the patient was successfully treated and remains in Aduro BioTech's study, the revelation suggests industry watchers will need to watch closely for any potential safety headwinds moving forward.
Regardless, the potential to teach the immune system how to more effectively fight pancreatic cancer using vaccines is immensely intriguing and everyone will be eagerly awaiting results from NewLink Genetics phase 3 trials. The estimated primary completion date for this trial is Dec. 2016.
