Trial results for Plozasiran (NCT05089084) in adults with familial chylomicronemia syndrome (FCS) were posted on ClinicalTrials.gov on 2026-02-04. The Phase 3 study demonstrated that Plozasiran 25 mg achieved a median 80.1% reduction in fasting triglycerides at Month 10 compared to -17.1% for placebo.
Background
The study evaluated Plozasiran (also known as ARO-APOC3) for the treatment of familial chylomicronemia syndrome (FCS) in adult participants. FCS is the condition targeted by this investigation.
Trial design
The Phase 3 study (NCT05089084) was designed to evaluate the efficacy and safety of Plozasiran in adult participants with familial chylomicronemia syndrome (FCS). The trial enrolled 75 participants, who were randomized to receive either Plozasiran or a matching placebo administered subcutaneously. Participants received 4 doses during the randomized period, followed by a 2-year open-label extension period where all participants would receive Plozasiran.
Key results
The trial reported significant reductions in fasting triglycerides (TG) and apolipoprotein C-III (APOC3) levels from baseline:
- For "Percent Change From Baseline at Month 10 in Fasting Triglycerides (TG)": The Plozasiran 25 mg group showed a median change of -80.1 percentage change, and the 50 mg group showed -77.6 percentage change, compared to -17.1 percentage change for Placebo.
- For "Percent Change From Baseline in Fasting TG at Month 10 and Month 12 (Averaged)": The Plozasiran 25 mg group showed a median change of -77.7 percentage change, and the 50 mg group showed -71.0 percentage change, compared to -2.6 percentage change for Placebo.
- For "Percent Change From Baseline in Apolipoprotein C-III (APOC3) at Month 10": The Plozasiran 25 mg group showed a median change of -92.95 percentage change, and the 50 mg group showed -96.20 percentage change, compared to -1.25 percentage change for Placebo.
- For "Percent Change From Baseline in Fasting APOC3 at Month 12": The Plozasiran 25 mg group showed a median change of -89.30 percentage change, and the 50 mg group showed -87.73 percentage change, compared to 7.69 percentage change for Placebo.
Statistical analyses using the Wilcoxon rank-sum test indicated significant differences between groups, with reported p-values of 0.0001 and 0.0002. Specific analyses showed median differences (Final Values) of -58.7 (95.0% CI: -89.6 to -27.9), -52.5 (95.0% CI: -83.1 to -21.9), and -59.6 (95.0% CI: -91.6 to -27.5), all with p-values of 0.0001 or 0.0002. The Holm method was also applied, yielding p-values of 0.0001 and 0.0002.
What this means
The results from this Phase 3 trial indicate that Plozasiran significantly reduced fasting triglyceride and apolipoprotein C-III levels in adults with familial chylomicronemia syndrome compared to placebo. The substantial percentage reductions observed across both doses suggest that Plozasiran could offer a meaningful therapeutic option for managing the severely elevated triglyceride levels characteristic of FCS. These findings are important for clinicians and patients seeking effective treatments for this condition.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT05089084, titled "Study of ARO-APOC3 (Plozasiran) in Adults With Familial Chylomicronemia Syndrome (FCS)," were posted on 2026-02-04 on clinicaltrials.gov.