Phase 1 Trial of Betalutin, a Radioimmunotherapy, in Advanced DLBCL Now Fully Enrolled

The Phase 1 trial evaluating Betalutin — an investigational tumor-targeting antibody labeled with a type of radiation — in people with relapsed or refractory diffuse large B-cell lymphoma (DLBCL) is now fully enrolled, its developer, Nordic Nanovector, announced.

The ongoing LYMRIT 37-05 trial (NCT02658968) includes 18 patients who are not eligible for an autologous stem cell transplant. It aims to determine the safety, optimal dose, and preliminary signs of effectiveness of a single dose of Betalutin (¹⁷⁷Lu-satetraxetan-lilotomab).

Taking place at sites across the United States and Europe, the trial will also determine the therapy’s overall stability and its pharmacokinetic profile: how it is absorbed, transported, metabolized, and excreted.

Interim results are expected to be announced later this year.

“We are delighted to have reached this important milestone and look forward to the preliminary results during the second half of the year,” Lisa Rojkjaer, MD, chief medical officer at Nordic Nanovector, said in a press release.

Patients will receive ascending doses of Betalutin to determine its safest and most effective dose. Once that dose is decided, the trial is set to expand to further assess the dose’s safety and efficacy  in this difficult to treat form of non-Hodgkin’s lymphoma.

“We expect more patients to be enrolled when the best dose is selected from the first part of the study,” Rojkjaer said.

Betalutin, a form of radioimmunotherapy, is the first of a new generation of antibody-radionuclide-conjugates (ARCs). It combines an antibody against the CD37 molecule labeled with the radioactive particle lutetium-177 (Lu-177), which cause irreversible breaks in the DNA and triggers cell death.

The CD37 molecule is found at the surface of most B-cell lymphoma cells. With this combination, Betalutin is designed to target the radioactive particle specifically against lymphoma B-cells while avoiding healthy cells.

Results from an ongoing Phase 1/2 trial of Betalutin in relapsed non-Hodgkin’s lymphoma — called LYMRIT 37-01 (NCT01796171) — report that the treatment reduced tumor burden in 63% of patients, with tumors in 29% of patients completely disappearing.

It is also seen to be well-tolerated, with most adverse events being blood-related and transient or reversible.

Betalutin is also being being studied as a treatment for relapsed or refractory follicular lymphoma patients, either alone in the second part of LYMRIT 37-01, called PARADIGME, and in combination with Rituxan (rituximab), in the ARCHER-1 Phase 1 trial (NCT03806179).

Both studies are recruiting eligible patients, for more information click on their identifying NCT numbers.