An investigative oral therapy, duvelisib, was effective in treating indolent non-Hodgkin’s lymphoma among patients who did not respond to Rituxan (rituximab) and chemotherapy or radioimmunotherapy, according to results from a Phase 2 clinical trial (NCT01882803).
The Verastem-sponsored trial reported a 43 percent overall response rate in patients with follicular lymphoma, and a 68 percent response rate in those with small lymphocytic lymphoma. Only 33 percent of patients with marginal zone lymphoma responded to the treatment. (Indolent non-Hodgkin’s lymphoma covers a range of lymphoma subtypes, but all progress slowly. This can make treatment difficult.)
“We believe that oral duvelisib has the potential to be an important new treatment option for lymphoma patients,” Pier Luigi Zinzani, an MD and PhD at the University of Bologna Institute of Hematology and a study investigator, said in a press release.
Zinzani presented the study, “DYNAMO: A Phase 2 Study Demonstrating the Clinical Activity of Duvelisib in Patients With Double-Refractory Indolent Non-Hodgkin Lymphoma,” at the recent 22nd Congress of the European Hematology Association (EHA) in Madrid.
Among the responding follicular lymphoma patients, one had a complete response, and 35, or 42 percent, had a partial response. The treatment continued to keep tumors in check for a median of 7.9 months, median progression-free survival was 8.3 months, and the patients lived for a median of 27.8 months.
All those with small lymphocytic lymphoma had partial responses. They had a median duration of response of 10.1 months, a median progression-free survival of 11.7 months, and lived for a median of 28.9 months.
Most reported side effects of duvelisib were mild or moderate. Those reported as more severe — grade 3 or 4 — were mostly effects on blood cell counts.
Researchers noted severe infections in 20 percent of follicular lymphoma patients and 36 percent of small lymphocytic lymphoma patients. This was an expected finding, they said, considering the patients had gone through several previous rounds of cancer treatment.
“What I find particularly encouraging are the responses we saw in patients with double-refractory disease, a population with few treatment options left. The data we are presenting at EHA continue to demonstrate that duvelisib monotherapy can achieve meaningful and durable responses,” Zinzani said.
“The data from DYNAMO remain positive, and reporting the results from long-term follow-up is important for the medical community and for the overall development of duvelisib,” added Hagop Youssoufian, MD, head of Hematology and Oncology Development at Verastem.
Duvelisib is an oral treatment targeting enzymes — specifically, PI3K-delta and PI3K-gamma — that promote the growth and survival of cancerous B- and T-cells.
In addition to the DYNAMO study, the drug is also being explored in a Phase 3 clinical trial (NCT02004522) in patients with relapsed or refractory chronic lymphocytic leukemia or small lymphocytic lymphoma. Studies independent of duvelisib’s developer, Verastem, are also ongoing.
“Oral duvelisib monotherapy has demonstrated clinical activity across a number of hematologic cancers, including chronic lymphocytic leukemia, iNHL, and T-cell lymphoma. Based on the results we have seen thus far, we remain fully committed to exploring duvelisib’s potential across a wide range of lymphoid malignancies,” Youssoufian said.