Combining Alpha DaRT® and Immunotherapy: Early Results and Clinical PromiseAn interview with Prof. Aron Popovtzer

alphataumedical8
Jul 10
2 min read

Combining Alpha DaRT® and Immunotherapy: Early Results and Clinical Promise

An interview with Prof. Aron Popovtzer, Director of Sharett Oncology Institute, Hadassah Medical Center

As part of Alpha TAU’s ongoing exploration into combination therapies, Prof. Aron Popovtzer is leading a study evaluating the synergy between Alpha DaRT and pembrolizumab in patients with inoperable head and neck cancer at Hadassah Medical Center in Jerusalem. In this discussion, Prof. Popovtzer shares insights on the study, patient eligibility, and the early signals of clinical benefit that are shaping future research.

Which patients are eligible for the combination study with pembrolizumab and Alpha DaRT?

Prof. Popovtzer: Unfortunately, no. The best available treatment is pembrolizumab, but response rates are low. Only around 23% respond at all, and the proportion with a strong, durable response is closer to 8–10%, based on most studies.

Do these patients have other effective treatment options besides pembrolizumab?

Are there particular challenges that could make some patients ineligible for Alpha DaRT source insertion?

Prof. Popovtzer: Generally, most patients are eligible. Unlike standard Alpha DaRT applications where we aim to cover the full tumor, here we're using it to stimulate the immune system. That means it's often sufficient to implant Alpha DaRT sources in a small area within the tumor.

However, patients with only very small lung metastases that cannot be accessed for source placement would not be eligible.

What results have you seen so far in the trial?

Prof. Popovtzer:We’ve treated about 8 patients, and the early results are exciting:

Around 75% of patients showed a meaningful clinical response
Roughly 37.5% achieved a complete response

These numbers are dramatically higher than the ~22% seen with pembrolizumab alone. While this is still an early-stage study, the data is very promising and supports continued exploration.

Is there a scientific explanation for the synergy between Alpha DaRT and pembrolizumab?

Prof. Popovtzer:Yes. In preclinical models, we saw that the immune system is significantly altered by Alpha DaRT. Specifically, there's an increase in activated T cells and dendritic cells, and a decrease in inhibitory immune cells. We believe this is driven by tumor cell destruction, which releases antigens and activates immune pathways

Have there been any concerns with tolerability or side effects?

Prof. Popovtzer:No. So far, we’ve seen no additional side effects compared to standard Alpha DaRT or pembrolizumab treatments. Patients of all ages, including those over 100 years old, have tolerated the procedure well.