CARLSBAD, Calif., Nov. 13, 2020 /PRNewswire/ -- Ionis Pharmaceuticals, Inc. (NASDAQ:IONS) announced today that new data for ION449, an investigational antisense medicine designed to reduce plasma levels of proprotein convertase subtilisin/kexin type 9, or PCSK9, were presented today at the American Heart Association (AHA) Scientific Sessions. PCSK9 is integrally involved in the regulation of LDL-cholesterol (LDL-C). Genetic studies have shown that individuals with life-long reduction of LDL-C due to reduced function of PCSK9 have substantially reduced risk of cardiovascular disease.
ION449, also known as AZD8233 for subcutaneous administration and AZD6615 for oral administration, is being developed as part of a collaboration between Ionis and the biopharmaceutical company AstraZeneca. ION449 incorporates Ionis' advanced Generation 2.5 and LIgand Conjugated Antisense, or LICA, technology. In a Phase 1 study, single subcutaneous doses of ION449 demonstrated dose-dependent reductions in circulating plasma PCSK9 protein and LDL-C levels of up to >90 percent and up to ~70 percent, respectively, in humans with a baseline LDL-C between 100 and 190 mg/dL.1 Doses of 4, 12, 20, 30, 60, 90 and 120 mg were evaluated. The single 90 mg dose was the minimum dose required to achieve maximum reduction in PCSK9 and LDL-C. ION449 was observed to be safe and well tolerated at all dose levels.
In addition, the feasibility of oral administration of ION449 was established in three in vivo studies:
- A study in rats demonstrated liver bioavailability of 5 percent with ION449 following intrajejunal administration, mimicking oral administration of tablets not feasible in rodents.
- A study in dogs demonstrated liver bioavailability of 7 percent following ION449 oral tablet administration for 28 days.
- A study in healthy monkeys found repeated oral administration of ION449 tablets for 14 days resulted in LDL-cholesterol reductions of 45–50 percent.
An oral formulation of ION449 is currently being evaluated in a Phase 1 study in healthy volunteers.
"Even with existing treatments, cardiovascular disease remains the leading cause of death worldwide, affecting tens of millions of people. Additional treatments are clearly needed for patients still at risk. The data from these studies are very encouraging and demonstrate the best-in-class potential of ION449 for lowering LDL-C via PCSK9 reduction for the treatment of patients with high cholesterol who are at risk of cardiovascular disease," said Brett P. Monia, Ph.D., chief executive officer at Ionis.
The full poster presentations, "Single Dose Safety, Pharmacokinetics, and Pharmacodynamics of a Potent PCSK9 Synthesis Inhibitor, AZD8233, in Subjects With Elevated LDL Cholesterol" (Poster #MP515) and "An Oral Antisense Oligonucleotide for PCSK9 Inhibition in Humans" (Poster #P244) are available to view on the AHA Scientific Sessions website.
Ionis' collaboration with AstraZeneca focuses on leveraging Ionis' pioneering antisense technology to discover and develop antisense therapies and AstraZeneca's expertise in drug development and commercialization. In addition to cardiovascular programs, the companies are also collaborating to discover and develop antisense drugs to treat cancer, metabolic and other diseases.