Long-term follow-up of the JULIET trial showed patients with relapsed or refractory DLBCL continued to experience durable responses 19 months after treatment.
Kymriah (tisagenlecleucel) continued to show durable responses among patients with relapsed or refractory diffuse large B-cell lymphoma (DLBCL), according to long-term follow-up of the JULIET trial.
The 19-month follow-up, presented at the 2018 American Society of Hematology (ASH) Annual Meeting, demonstrated an objective response rate of 54 percent with the CD19-targeted chimeric antigen receptor (CAR)-T cell therapy, further supporting use of Kymriah in patients with relapsed or refractory disease who otherwise did not have viable treatment options.
“The reason this is important is because early on you always wonder if there is selection bias. As you move into 19 months, you're really looking at the natural history of the disease,” senior investigator Richard T. Maziarz, M.D., from the Oregon Health & Science Knight Cancer Institute explained during a press conference at the meeting, held Dec. 1-4 in San Diego.
DLBCL, the most common form of lymphoma, accounts for approximately one-third of all non-Hodgkin lymphoma cases. While frontline therapy is effective, about one-third of patients with DLBCL relapse or progress, and half are not eligible for stem cell transplantation.
After the initial analysis of the JULIET trial, the Food and Drug Administration (FDA) approved Kymriah to treat adult patients with relapsed or refractory DLBCL after two or more lines of systemic therapy in May 2018.
In the single-arm, open-label, global, phase 2 JULIET trial — conducted at 27 treatment sites across 10 countries – 115 patients (median age, 56 years) received Kymriah. Patients had to have received two or more previous treatments with documented disease progression or failed to respond or were otherwise ineligible for autologous stem cell transplant.
Objective response rates (complete and partial remission rates) served as the primary endpoint, while secondary endpoints included duration of response, overall survival and safety.
In total, 40 percent of patients experienced complete remission and, of note, 54 percent of patients who initially had a partial response ended up having a complete response.
The six-month relapse-free survival rate was 66 percent, which remained consistent at 64 percent at both the 12- and 18-month data analyses. Median overall survival was 11.1 months; however, this was not reached for those who achieved a complete remission; and 12- and 18-month overall survival rates were 48 percent and 43 percent, respectively.
“What we see is that we're approaching a plateau, and we're definitely seeing a change in the natural history of the disease,” Maziarz explained.
Consistent with previous findings, severe side effects occurred shortly after infusion, including a drop in mature blood cells (34 percent), cytokine release syndrome (23 percent), infection (19 percent) and neurological events (11 percent). No deaths occurred from therapy.
“Before CAR-T cell therapy, achieving and maintaining a prolonged complete response in adult patients with relapsed or refractory DLBCL was incredibly rare, but now we are seeing Kymriah result in durable complete responses more than a year and a half after infusion,” lead author Stephen J. Schuster, M.D., director of the Lymphoma Program at the Abramson Cancer Center at the University of Pennsylvania in Philadelphia, said in a press release.
“Duration of response and a consistent safety profile are incredibly important data points,” he added. “and the findings from this updated analysis further instill confidence in the continuing potential of Kymriah in the treatment of these patients.”