Eli Lilly shared early clinical data on the BTK inhibitor it acquired with Loxo Oncology—and the numbers have Lilly outlining plans for “an ambitious comprehensive development program."
Lilly’s new commitment is based on results from a phase 1/2 that had enrolled 28 heavily pretreated patients as of the cutoff and assigned them to receive one of five doses of LOXO-305. Lilly shared the data Sunday at the 2019 American Society of Hematology annual meeting.
Among the 16 chronic lymphocytic leukemia (CLL) patients in the trial, Lilly recorded eight partial responses and two partial responses with ongoing lymphocytosis, and all 10 are still benefiting from the therapy. As only 13 of the CLL patients were evaluable, Lilly put the objective response rate (ORR) at 77%.
And those responses came in patients who'd failed on a series of previous treatments. On average, the CLL patients had received four prior rounds of systemic therapy. Three-quarters of the patients had previously taken at least one BTK inhibitor, such as AbbVie and Johnson & Johnson’s Imbruvica.
Lilly and Loxo enrolled a similarly hard-to-treat set of mantle cell lymphoma (MCL) patients. In that 8-patient subgroup, Lilly saw one complete response and two partial responses. With only six of the MCL patients eligible for response assessment, Lilly put the ORR at 50%.
When coupled with a safety and tolerability profile featuring two grade three or higher adverse events attributable to LOXO-305, Lilly saw the efficacy data as a big, albeit early, plus for the drug's prospects.
“Put simply, LOXO-305 has exceeded our expectations. LOXO-305’s wide therapeutic index allows us to plan and implement an ambitious comprehensive development program, one that includes combination regimens that exploit the drug’s selectivity profile,” Jacob Van Naarden, chief operating officer of Loxo Oncology at Lilly, said in a statement.
Those comments may cause a few regrets at Redx Pharma, which was forced to sell the drug to Loxo for $40 million in 2017 to escape a debt crisis. The agreement was devoid of milestones or royalties.
For Lilly, the plans for LOXO-305 create a focal point for its new-look cancer group. Thursday, Lilly said it is combining the oncology wing of its research laboratories with Loxo, the biotech it bought for $8 billion earlier this year. The resulting group, named Loxo Oncology at Lilly, will be run by three members of the Loxo C-suite.