Positive Zerlasiran Phase 2 Results in High Lp(a) Patients

Silence Therapeutics, a leading biotechnology firm, has reported encouraging results from the ALPACAR-360 phase 2 clinical trial of zerlasiran (SLN360). The study, which included 178 participants with high baseline levels of lipoprotein(a) (Lp(a)), or more than 125 nmol/L, and who are at elevated risk of atherosclerotic cardiovascular disease (ASCVD), showed significant reductions in Lp(a) levels. Zerlasiran is a siRNA designed to decrease the production of Lp(a), a genetic risk factor for cardiovascular disease that impacts a substantial portion of the global population.

During the double-blind, placebo-controlled phase of the study, zerlasiran was administered subcutaneously at varying dosages and intervals. The treatment resulted in a highly significant reduction in Lp(a) levels compared to the placebo group, achieving the study's primary endpoint at 36 weeks. Notably, both dosages demonstrated a median percentage reduction of 90% or greater in Lp(a) levels by week 36, with no new safety concerns arising.

The study is ongoing, with the 60-week mark still to be reached. Secondary endpoints will include further evaluation of Lp(a) levels at 48 and 60 weeks, as well as potential effects on other lipids and lipoproteins. Silence Therapeutics is excited by the phase 2 data, which align with phase 1 results, and they anticipate reviewing the 48-week data soon with the aim of advancing zerlasiran as a potential treatment for high Lp(a) levels, a significant unmet need in cardiovascular disease management.

Silence Therapeutics is pioneering the development of a new class of medicines that leverage the body's RNA interference (RNAi) mechanism to inhibit the expression of genes associated with diseases that have significant unmet medical needs. Their proprietary mRNAi GOLD™ platform enables the creation of siRNAs that precisely target and silence liver genes related to disease. Silence's product pipeline includes zerlasiran, aimed at reducing cardiovascular risk in individuals with high Lp(a) levels, and divesiran, intended for the treatment of hematological disorders such as polycythemia vera. The company also collaborates with other pharmaceutical entities like AstraZeneca and Hansoh Pharma for research and development purposes.

The company plans to release the topline 48-week data from the ALPACAR-360 study in the second quarter of this year, which will provide further insights into zerlasiran's potential as a treatment for cardiovascular disease.