Another Rosenberg trial NCT03412877 sharing a similar title to the new Ziop trial also started as a Phase 2. I believe it's because the underlying concepts have been proven in prior trials.
- This initially was tumor resection + TIL creation over 4-6 weeks, but was changed at some point to include PBL's targeting KRAS and p53. Ziopharm's license with NCI is for those same targets, but with use with SB.
- Enrollment was limited to 1 patient a month in each of the 4 cohorts.
- It is anticipated that approximately one patient per month may enroll on the trial for each of the four histologic groups. Thus, accrual of up to 4 x 50=200 total evaluable patients may be completed in approximately 2-4 years. In order to allow for a small number of inevaluable patients, the accrual ceiling will be set to 210.
I think something not being discussed much on these boards is understanding what TIL is. The body is trying to attack the tumor, but isn't providing enough lymphocytes to get the job done. They remove the tumor and cut it into tiny bits. They then culture them in different media and see what is reactive. They then grow that portion into the tens of billions. It is called "bulk TIL" because it isn't creating a product based on any genetic identification or modification. It is trusting that the body created the right lymphocytes, just not it enough capacity.
So Rob is trying to tell everybody that TIL's aren't the answer, but nobody is saying it is. It's a better answer than existing solutions in melanoma and cervical. Just like how autologous CD19 "can't scale" doesn't mean investors in those first to market technologies won't be rewarded. PBL's are very different than TIL.