Janssen has unveiled updated results from a mid-stage trial of its CAR-T therapy JNJ-4528, showing high rates of response in patients with relapsed or refractory multiple myeloma.

Data from the Phase Ib/II CARTITUDE-1 study show that all patients responded to treatment and the responses were deep and durable, with 86% achieving complete response at a median follow-up of 11.5 months and 86% being alive and progression free at nine months.

The 100% overall response rate (ORR) included 97 percent of patients achieving a very good partial response or better and three percent achieving a partial response, the firm noted.

Also, responses were observed among heavily pretreated patients (n=29), who had received a median of five (range, 3-18) prior treatment regimens; 86% were triple-refractory and 28% were penta-refractory. The median time to first response was one month, and 81% of evaluable patients achieved minimal residual disease (MRD)-negative disease status at the time of first suspected complete response.

“The longer-term results for JNJ-4528, as demonstrated through the latest findings from the CARTITUDE-1 study, show the continued treatment effect for heavily pretreated patients who faced a dismal prognosis,” said Jesus G Berdeja, director of Myeloma Research, Sarah Cannon Research Institute, and principal study investigator.

“We’re encouraged by not only the relatively high rate of stringent complete responses, but also the progression-free survival seen in these patients.”

On the safety side, the most common adverse events observed in CARTITUDE-1 were neutropenia (100%) and cytokine release syndrome (CRS, 93%). In patients who experienced Grade 3 and above AEs, the most common were neutropenia (100%), thrombocytopenia (69%) and leukopenia (66%).

Neurotoxicity consistent with immune effector cell-associated neurotoxicity syndrome (ICANS) was observed in three patients (10%), including one patient (3%) with Grade 3 or greater toxicity.

Three deaths were reported during the Phase Ib study: one due to CRS, one due to acute myeloid leukaemia (not treatment-related) and one due to progressive disease.