Juno turns to JCAR017 amid Rocket setback
- Battered by tragic trial missteps and pipeline doubts, Juno Therapeutics presented some much-needed good news on Monday, releasing early positive data on its CAR-T therapy JCAR017 at the American Society of Hematology meetings in San Diego.
- Treatment with JCAR017 initially led to a complete response in 60% of patients with non-Hodgkin lymphoma (NHL). After three months, eight of 19 patients with diffuse large B-cell lymphoma (DLBCL) continued to experience a response.
- Yet the promising results are overshadowed by the two patient deaths recently observed in the ROCKET study testing Juno's JCAR015, once the lead clinical candidate. That trial is currently on ice and Juno is mulling its options for moving forward.
Out of context of Juno's current circumstances, the data presented on JCAR017 would likely have given a boost to the cell therapy company.
The overall response rates following treatment hit a competitive 80% in the 20 efficacy-evaluable NHL patients. And the 42% response rate seen among DLBCL patients 3 months post-treatment matches up against Kite's KTE-C19 therapy in that indication, albeit in about a third as many patients and in an early stage study.
Importantly, no patient deaths or severe cytokine release syndrome were reported. Fourteen percent of patients did experience grade 3/4 neurotoxicity, however, which also compares favorably to the 29% rate seen in Kite's study.
Yet the new patient deaths in Juno's ROCKET study have sparked doubts about the company's prospects, along with raising questions about the company's haste to restart patient treatment following three other deaths over the summer.
When the Food and Drug Administration halted ROCKET in July, Juno blamed the interaction between the pre-conditioning chemo agent fludarabine and the enhanced T-cells for the fatal reactions.
But even without fludarabine, treatment with JCAR015 still led to deadly cerebral edema in two of the 30 patients who only received only cyclophosphamide as pre-conditioning, according to a presentation given by the company late Monday night.
In total, Juno has treated 38 patients with JCAR015. With five deaths, the overall treatment-related mortality rate sits at an unacceptably high 13%.
Juno is now considering three options: modifying ROCKET with a new treatment protocol, starting over with another trial or scrapping the program altogether.
Even before the deaths, Juno was highlighting JCAR017 over JCAR015. Monday's positive results for JCAR017 will likely accelerate that pivot.
Still, a registrational trial for JCAR017 won't happen until sometime next year, meaning Juno likely won't have a shot at market until 2018 or later — a year or more behind rivals Kite Pharma and Novartis.
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