ASH: A New RadioImmunoTherapy Treatment?

In the U.S., we're dealing with a sad decline in the use of RadioImmunoTherapy (RIT). Bexxar is no longer available to patients, and Zevalin is being made difficult to use because of unreasonable government regulations.

But that doesn't mean RIT is dead yet (we need to keep fighting for it in the U.S., people).

More importantly, there's another RIT treatment in early clinical trials in Europe, and results are bing reported at ASH.

The treatment is called Betalutin, and the ASH report is called ^"177lu-Satetraxetan-Lilotomab in the Treatment of Patients with Indolent Non-Hodgkin B-Cell Lymphoma (NHL), Phase 1/2 Safety and Efficacy Data from Four Different Pre-Dosing Regimens."

Like other RIT treatments, this one involves attaching a small amount of radiation to  monoclonal antibody that targets a protein on lymphoma cells. Zevalin, for example targets the protein CD20. The new RIT treatment, Betalutin, targets a different protein, CD37.

Many of the same researchers from the ASH study reported in Blood journal a couple of years ago that Betlutin seemed safe, with manageable side effects. I assume the ASH results are from the same trial, or a related one, given the overlap in researchers, but I don't know that for sure. Whatever the case, the ASH presentation gives a more detailed look at the results.

They describe this as a phase 1/phase 2 trial, so it's fairly small -- 36 patients enrolled, 23 able to evaluated, and 20 of those 24 had Follicular Lymphoma. Patients were divided into 4 groups. Because it's an early trial, part of the goal is to see which is the most effective way of giving the treatment, each of those 4 groups was given the Betalutin in a slightly different way. All of them were given a dose of Rituxan first, and then they were given some combination of Rituxan and/or Lilotomab (an anti-CD37 monoclonal antibody), and then Betalutin.

Patients were given a PET/CT scan at 3 months and 6 months after they finished treatment, and then after 5 years. There were some side effects, but no deaths and so secondary cancers as a result of the treatment.

The results were pretty good. The Overall Response rate was 57% (7 Complete Responses and 6 Partial Responses). 5 patients has stable disease, which left 5 whose disease got worse.

The researchers' conclusion: "Betalutin has the potential to be a novel, safe and effective therapy for B-cell malignancies with durable responses. Betalutin, a single dose, ready-to-use formulation, has a predictable and manageable safety profile which is improved by pre-dosing. Most AEs were haematological, all transient and reversible."

RIT works. That's all there is to say. I hope Betalutin proves to be effective in future, larger trials, and it helps you folks in Europe. As for us in the U.S., I hope this type of treatment doesn't go away. We have lots of arrows in our quiver, and I'd hate to see us lose even one -- especially one that has done so much good for so many people.