Thanks for the thoughtful questions, Mary. You’re absolutely right—ALC is a powerful prognostic marker, and we’ve now demonstrated across >10 tumor types, including lung cancer, that preserving or restoring lymphocytes directly correlates with prolonged overall survival. So from a prognostic marker to a treatable modifiable condition of lymphopenia.
Radiation, including targeted radioligands like Pluvicto, can profoundly suppress ALC. What we’ve seen is that administering Anktiva (IL-15 superagonist) both before and during radiation protects and expands CD8⁺ and NK cells, preserving immune competence during treatment.
We are actively recruiting patients for our lung cancer and GBM trials and expanding into prostate cancer, including combinations with Pluvicto, to test this “immune shield” concept in mCRPC. We have shown that maintaining ALC above ~1,000/μL during radiation results in rapid drop of PSA levels to undetectable.
We’d welcome your input as a radiation oncologist. Happy to arrange a discussion—our team can walk through the trial designs, inclusion criteria, PD-L1 correlations, and planned endpoints for prostate, head and neck and GBM cancers.
Appreciate your engagement and scientific curiosity—it’s exactly this collaboration that drives the field forward.
Dr. Soon-Shiong, this is an interesting thread on ALC as a prognostic factor, and Anktiva's potential as a Bioshield for mCRPC w/Pluvicto.
I am not familiar with Anktiva and have some questions based on a quick review of trial data (mostly for bladder ca and NSCLC) for consideration of integrating EAP for our mCRPC patients starting Pluvicto (Gleason 6-7 vs 8-10, ECOG 0-1 vs 2, low vs high burden disease).
I don't expect a detailed response, but if you have any resources that contain this info, it would be welcome. I assume you get asked these questionsa lot.
- You mention that all tumors can benefit. Prostate ca has low TIL and low TMB / PD-L1. It seems like the greatest benefit is expected with tumors that have both low TIL and high TMB / PD-L1 (for synergistic effect), correct? Also, Pluvicto's lymphopenia risk is low compared to other systemic treatments such as taxanes (14.2% any grade, 7.8% grade 3/4 per VISION).
- Given these factors, what would be the difference in efficacy you've seen using this with prostate ca vs NSCLC? Do you think any combo like adding an ICI (ie, pembro) would bridge the gap?
- How many mCRPC patients have you treated in conjunction with Pluvicto? Out of those cases, what ALC recovery rate do you see w/concurrent C1 vs reactive (post-nadir) timing? And for those who have ALC recovery, what % have at least PSA50? (If you have data that stratifies as above, that would be ideal.)
- What % are non-responders? And what biomarkers (ie, NK, CD8+) best predict secondary ALC drops by 3 months and 6 months (especially in patients with high-burden disease / Gleason 9-10) - assuming you check flow cytometry at baseline and at certain times post-infusion?
- What are the inclusion/exclusion criteria for approving individual EAP cases at this time and what is the OOP cost to patients?
- Do you have a plan for phase 2 and 3 mCRPC clinical trials? If not, could you expand the QUILT trial and add an arm with Pluvicto? Also, what are the endpoints (ie, PFS, OS, etc) in lymphopenic population and the timeline for site activation (if say I had interest in being PI at our Cancer Center that handles Pluvicto)?
- Finally, in preliminary analyses, how does Anktiva impact QOL metrics (pain, mobility, etc) in patients with symptomatic mets vs Pluvicto alone, and any decrease in side effects, such as xerostomia, n/v, or cytopenias?
I know these are a lot of questions. I'm interested in learning more and seeing if this is something that might be appropriate for some of our prostate patients.
Thanks, Mary