Summary of IPI-145 Data in Advanced Hematologic Malignancies Presented at ICML
In total, the Phase 1 data of IPI-145 reported in three separate presentations at ICML included patients with B-cell lymphoma (51 patients evaluable for safety and 38 for response), CLL (34 patients evaluable for safety and 22 for response) and T-cell lymphoma (17 patients evaluable for safety and nine for response). 2,3,4 These patients had advanced disease and had progressed during or were refractory to, intolerant of, or ineligible for established therapy. Patients had a median of four prior systemic therapies (range: 1 to 13), and 69 percent of patients had at least three prior systemic therapies.
Safety data presented in all three presentations showed that IPI-145 was well tolerated, with a safety profile consistent with co-morbidities seen in patients with advanced hematologic malignancies. There have been no dose-related trends in adverse events at the doses evaluated.
Data also showed that IPI-145 is rapidly absorbed and demonstrates a linear pharmacokinetic (PK) profile through 75 mg BID, with complete inhibition of PI3K-delta and at least 50 percent inhibition of PI3K-gamma at doses ≥ 25 mg BID. IPI-145 rapidly decreased the levels of several cytokines and chemokines known to be important in lymphocyte trafficking and function. Additionally, rapid, sustained inhibition of AKT phosphorylation (a marker of PI3K inhibition) was observed in CLL cells from patients treated with IPI-145, with no difference observed between the 25 mg and 75 mg doses.Data reported showed that IPI-145 is clinically active across a broad range of patients with advanced hematologic malignancies, with responses observed in patients with iNHL, CLL, T-cell lymphoma, MCL and HL. The onset of activity was rapid, with a median time to response of less than two months (range: 1.6 – 5.6 months). Additional Phase 1 data reported included the following: