A Phase 1 trial evaluating Betalutin, an anti-CD37 antibody attached to a radioactive compound, in patients with relapsed diffuse large B-cell lymphoma (DLBCL) has dosed its first participant.
The trial is enrolling patients who received at least one prior line of rituximab-containing chemotherapy (R-CHOP) and who are not eligible for an autologous stem cell transplant.
“We are excited to begin this study to evaluate Betalutin in patients with relapsed DLBCL who are ineligible for stem cell transplantation. This is an area of significant medical need with no approved treatment options,” Dr. Lisa Rojkjaer, chief medical officer of Nordic Nanovector, said in a press release.
“The encouraging data seen in the Phase 1/2 study in relapsed indolent NHL [non-Hodgkin’s lymphoma], presented at ASH in December 2016, provide a strong foundation to advance our development of Betalutin into this second indication,” she said.
DLBCL, the most common non-Hodgkin’s lymphoma subtype, is currently treated with R-CHOP as a first-line therapy. However, nearly 40% of patients relapse, and only 30% to 40% of relapsed patients respond to high-dose chemotherapy followed by stem cell transplant.
Betalutin, the first of a new generation of antibody-radionuclide-conjugates (ARCs), is a mouse antibody that targets the CD37 molecule attached to the beta-emitting isotope lutetium-177 (Lu-177).
The CD37 molecule is expressed by adult B-cells and is found at the surface of most B-cell lymphoma cells. Radioactive beta particles induce tumor cell death by causing irreversible breaks in the DNA strand; their limited range avoids impact on healthy cells.
Betalutin is a promising approach for patients that did not respond to standard CD20-based therapies (rituximab), having a potential synergistic effect with such therapies.
Data presented at the American Society of Hematology 2016 Annual Meeting and Exposition has shown promising results from the Lymrit 37-01 Phase 1/2 trial of Betalutin in relapsed non-Hodgkin’s lymphoma (NCT01796171).
In a total of 35 evaluable patients, 10 achieved a complete response, and 11 achieved partial responses. This amounted to an overall response rate of 63% and complete response rate of 29%.
The treatment was also well tolerated, with most adverse events being blood related and transient or reversible.
The new Phase 1 trial, called LYMRIT 37-05 (NCT02658968), is an open-label, single-arm, dose escalation study designed to evaluate the safety and preliminary anti-tumor activity of Betalutin.
The trial will enroll up to 24 patients in cancer centers in the U.S., Germany, Italy, Spain, and in the U.K. It will be led by Prof. Timothy Illidge at the Manchester Cancer Research Centre at the University of Manchester, England.