This study is looking at a treatment called Plozasiran for adults with severe hypertriglyceridemia, a condition where you have very high levels of triglycerides, a type of fat, in your blood. Participants will receive either Plozasiran or a placebo (a fake treatment) every 3 months for a year. After the first year, participants can choose to continue with the real treatment if they want. To join, you need to have a history of very high triglycerides and be willing to follow a low-fat diet. The study also checks that you don’t have certain other health conditions or use certain medications.

• The study lasts for 12 months, with visits every 3 months.
• Participants may switch to real treatment after 12 months.
• Eligibility requires maintaining a low-fat diet.