Ziopharm Oncology (TCRT -1.71%) and competitors Juno Therapeutics (JUNO) and Kite Pharma (NASDAQ: KITE) are in a horse race of sorts to develop an entirely new way of battling cancer. All three companies are developing chimeric antigen receptor T-cell therapies (CAR-T) that re-engineer a patient's immune system to better find and destroy cancer cells, and each has human trials under way to prove that CAR-T is both effective and safe. However, Ziopharm Oncology hopes that partnerships it has inked with Intrexon Corporation (PGEN 7.69%) and the MD Anderson Cancer Center mean its solution will be best in class.
First, a bit of background
Re-engineering T-cells to find cancer cells is no easy task. Currently, the process involves isolating a patient's T-cells outside the body, modifying them to so that they can bind to a protein expressed by a person's cancer, and then culturing them with antigen-presenting cells expressing the protein via viral transfection.
That process is time-consuming and costly, but in early-stage trials, it also appears to be effective.
For example, Juno Therapeutics reports that in its trials, 91% of 32 patients with recurring or relapsing acute lymphoblastic leukemia that were treated with its JCAR015 are in complete remission, and Kite Pharma reported in December that five of seven patients with refractory, aggressive large B cell lymphoma had either a complete or partial response to its KTE-C19 CAR-T therapy.
A better mousetrap
Traditional CAR-T therapies, however, aren't perfect solutions.
There have been cases of life-threatening cytokine responses, and the complexity of the viral-CAR-T approach makes it both costly and difficult to scale up for widespread use in patients.
Ziopharm hopes its CAR-T platform can sidestep those obstacles.
To reduce the risk of troublesome and unwanted immune system over-activity resulting from CAR-T, it licensed Intrexon's Rheoswitch technology. That technology allows Ziopharm to turn on and off, and more precisely control, gene expression via the use of an "activator" pill. Conceivably, Rheoswitch allows doctors to put the brakes on Ziopharm Oncology's therapy if toxicities develop in patients.
Additionally, Ziopharm Oncology cut a deal with the MD Anderson Cancer Center in January 2015 giving it access to a non-viral way of reengineering CAR-T cells and that approach may reduce the cost and complexity that's associated with CAR-T therapies.
Rather than relying on the time-consumer process of viral transfection, MD Anderson's approach involves inserting CARs that have been developed specifically for a patient into a specific DNA sequence that can change its location within the genome; and then modifying a patient's T-cells via electroporation. This non-viral approach, nicknamed Sleeping Beauty, could make Ziopharm Oncology's CAR-Ts far less cost-prohibitive to patients and payers, ultimately giving them an advantage over Juno Therapeutics and Kite Pharma.
Juno Therapeutics and Kite Pharma have the best chance of getting their CAR-Ts to market first.
Juno Therapeutics is conducting a phase 2 trial of JCAR015 that, if successful, management thinks could allow it to file for accelerated approval with the FDA in 2017. Similarly, management outlined a timeline during Kite Pharma's recent fourth quarter conference that could conceivably net the company a regulatory decision on KTE-C19 next year, too.
However, ultimately the real winner may not be the company that gets to market first, but instead, the company that delivers the most efficacious and safest therapy. If Rheoswitch and Sleeping Beauty give Ziopharm Oncology the edge in that department, then arriving to market after Juno Therapeutics and Kite Pharma may not matter. Only time will tell, however, if that's the case, and because anything can and often does go wrong in cancer trials, investors should approach all three of these CAR-T developers cautiously.