I had the pleasure of meeting Napster founder and the first Facebook President Sean Parker at a scientific meeting in Cambridge, Massachusetts 3 years back when he announced the launch of Parker Cancer Immunotherapy fund to facilitate research in cancer through a collaboration between the 7 leading cancer centers in the country.
One of the breakthrough achievements of the Parker Institute for Cancer Immunotherapy from the above $250M funding was highlighted this weekend at the ongoing American Association for Cancer Research conference. Preliminary results of an ongoing phase 1b clinical trial of a 4 drug combo of chemotherapy (2 chemo drugs)+anti-PD1 checkpoint inhibitor and CD40 antibody in advanced pancreatic cancer were released. The 4 drug combo was safe and well tolerated. Tumor shrinkage was seen in 20 out of 24 evaluable patients (83%), which is impressive considering the poor prognosis in these patients. Anti-PD1 checkpoint inhibitors which have shown success even as a monotherapy in many cancers have failed to show a benefit in pancreatic cancer. Several other immune-oncology combos have also failed in this cancer.
Pancreatic cancer is a notorious cancer to treat and the reason is that it has a thick fibrotic sheath surrounding the tumor which makes it difficult for the body’s T cells (forming the immune response) to enter the tumor and kill cancer cells. I have always favored that chemotherapy should be combined with immunotherapy combos as a first line treatment in cancers for the best response. In pancreatic cancer, chemo is likely to have busted this fibrotic sheath thus allowing the I/O combo to work effectively.
The possibility of increased toxicity is likely reason why investigators have stayed from this chemo+I/O combination. Merck showed success by combining chemotherapy with anti-PD1 checkpoint inhibitors as first line therapy in advanced non small cell lung cancer. The above mentioned results from Parker Institute show that first line combo treatments with even 4 drugs, including chemo are safe and efficacious. As one of the trial investigators commented, “"What we learn in this trial can inform the work being done on other solid tumor types, so that we can make immunotherapy beneficial for more patients.”
I suggested this combo strategy in a recent meeting with an immuneonc company’s CEO and was met with skepticism about increased toxicity. Parker Institute’s results have the possibility of changing the way cancer immunotherapy trials will be designed in the future, so stay tuned.
Not an investment advice. No position in the securities mentioned.