Infinity Pharmaceuticals, Inc. (NASDAQ: INFI) today reported preclinical data for IPI-145, the company’s oral inhibitor of phosphoinositide-3-kinase (PI3K)-delta and PI3K-gamma. The data demonstrate potent PI3K-delta and -gamma inhibition in biochemical, cellular and whole blood assays and activity in multiple preclinical models of inflammatory disease, including rheumatoid arthritis and asthma. These data, which represent the first reported characterization of IPI-145, were presented at the New York Academy of Sciences event, “Inositol Phospholipid Signaling in Physiology and Disease,” held in New York City.
“As these data demonstrate that IPI-145 is one of the most potent inhibitors of PI3K-delta and-gamma described to date, we believe that IPI-145 may have advantages over other PI3K inhibitors currently in development,” stated Vito J. Palombella, chief scientific officer at Infinity. “Inhibiting PI3K-delta and -gamma represents a potentially important therapeutic strategy for treating not only inflammation, but also hematologic malignances, and we are pleased to continue advancing IPI-145 in the clinic. Beyond IPI-145, we have an active discovery effort under way to build a portfolio of differentiated, isoform-specific PI3K inhibitors.”
Infinity also announced today that it plans to initiate a Phase 2 trial of IPI-145 in patients with asthma as well as a Phase 2 trial of IPI-145 in patients with rheumatoid arthritis in the second half of 2012. Additional details about these trials will be provided when the studies commence.
The PI3Ks are a family of enzymes involved in multiple cellular functions, such as cell proliferation and survival, metabolism, cell differentiation and cellular trafficking.
PI3K-delta and -gamma, two isoforms of PI3K, are involved in the development, function and trafficking of the immune system, making them potential therapeutic targets for both inflammatory disorders and hematologic malignancies.
IPI-145 is the only PI3K-delta and -gamma inhibitor currently in clinical development.
Preclinical Data Presented at the New York Academy of Sciences
Preclinical data presented today demonstrate that IPI-145 has picomolar affinity for PI3K-delta and -gamma, as well as potent isoform-specific
activity in several cellular and whole blood assays. In addition, IPI-145 is highly selective for PI3K as compared to other lipid and protein kinases.
Preclinical data also show that IPI-145 is active in an allergen challenge model of asthma. Additionally, in preclinical models of both collagen-induced arthritis and adjuvant-induced arthritis, IPI-145 inhibits ankle swelling and protects bone and cartilage in the joints of diseased animals. IPI-145 has also demonstrated activity in preclinical models of Crohn’s disease, systemic lupus erythematosus and multiple sclerosis. The presentation may be found in the Publications Archive on Infinity's website,
Planned Phase 2 Development
The planned Phase 2 trials in asthma and rheumatoid arthritis follow the completion of a Phase 1 double-blind, randomized, placebo-controlled trial in healthy adult subjects, which assessed the safety, pharmacokinetics and pharmacodynamics of single and multiple ascending doses of orally administered IPI-145. In the study, IPI-145 was well tolerated, with no clinically significant changes in clinical laboratory values or vital signs. In addition, an
pharmacodynamic assay demonstrated rapid, dose dependent, and durable inhibition of basophil activation at all dose levels. Infinity expects to present additional details from the Phase 1 study in healthy adult subjects at a medical meeting in the second half of 2012.
“Our first Phase 2 trials in asthma and rheumatoid arthritis, development paths with well-defined endpoints, are designed to allow us to quickly explore the tolerability and clinical activity of IPI-145 and to inform our path forward in autoimmune and inflammatory diseases,” said Pedro Santabárbara, M.D., Ph.D., chief medical officer at Infinity. “We are pursuing a dual development strategy in both inflammation and hematologic malignancies. Our Phase 1, dose-escalation trial of IPI-145 in patients with advanced hematologic malignancies is ongoing, and we anticipate presenting data from this trial in the second half of 2012.”