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Study of Olezarsen (ISIS 678354) for Patients with High Triglycerides and Heart Disease or Severe High Triglycerides

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying the effects of a treatment called Olezarsen (also known by its code name ISIS 678354) in individuals with Hypertriglyceridemia and Atherosclerotic Cardiovascular Disease, or those with severe hypertriglyceridemia. Hypertriglyceridemia is a condition where there are high levels of triglycerides, a type of fat, in the blood. Atherosclerotic Cardiovascular Disease involves the buildup of fats, cholesterol, and other substances in and on the artery walls, which can restrict blood flow. The study aims to evaluate how Olezarsen affects the levels of triglycerides in the blood compared to a placebo.

Participants in the study will receive either Olezarsen or a placebo through subcutaneous injection, which means the injection is given under the skin. The study will last for about 53 weeks, during which the changes in fasting triglyceride levels will be monitored. Fasting triglyceride levels refer to the amount of triglycerides in the blood after a period without eating. The study will also look at other health markers and events, such as changes in cholesterol levels and the occurrence of pancreatitis, which is inflammation of the pancreas, and major cardiovascular events like heart attacks or strokes.

The safety and tolerability of Olezarsen will be assessed by comparing it to the placebo. This includes monitoring for any adverse events, changes in vital signs, and results from physical exams and laboratory tests. The goal is to determine if Olezarsen is effective and safe for reducing triglyceride levels in patients with these conditions.

The research process

The trial runs in 8 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Initial visit

    Upon joining the study, an initial visit is conducted. During this visit, eligibility is confirmed based on specific criteria related to hypertriglyceridemia and cardiovascular disease. A clinical diagnosis is required, and current medications are reviewed to ensure they have been stable for at least four weeks.

  2. Step 2

    Randomization

    Participants are randomly assigned to receive either the study medication, olezarsen (ISIS 678354), or a placebo. This process is double-blind, meaning neither the participant nor the study team knows which treatment is being administered.

  3. Step 3

    Treatment administration

    The study medication or placebo is administered through a subcutaneous injection. The dosage and frequency are determined by the study protocol, and participants are informed of their specific schedule.

  4. Step 4

    Regular follow-up visits

    Regular follow-up visits are scheduled to monitor health and assess the effects of the treatment. These visits include physical examinations, laboratory tests, and other assessments to ensure safety and measure changes in triglyceride levels.

  5. Step 5

    Midpoint evaluation

    At week 25, a detailed evaluation is conducted to assess the percent change in fasting triglyceride levels compared to the baseline. This helps determine the effectiveness of the treatment.

  6. Step 6

    Continued treatment and monitoring

    Participants continue to receive the assigned treatment and attend regular follow-up visits. Monitoring for any side effects or adverse events is ongoing to ensure participant safety.

  7. Step 7

    Final evaluation

    At week 53, a final evaluation is conducted. This includes a comprehensive assessment of triglyceride levels and other health markers to compare with the initial baseline measurements.

  8. Step 8

    End of study procedures

    Upon completion of the study, participants undergo final health assessments. The study team provides information on the next steps and any necessary follow-up care.

Who can join the trial?

6 criteria

  • Participants must be either male or female.
  • Participants must be in one of the following age groups: 18-64 years or 65 years and older.
  • Participants must have one of the following conditions:
    • Hypertriglyceridemia with fasting triglyceride (TG) levels between 150 mg/dL (1.69 mmol/L) and 500 mg/dL (5.65 mmol/L).
    • Severe hypertriglyceridemia with fasting TG levels of 500 mg/dL (5.65 mmol/L) or higher.
    • Participants must have a clinical diagnosis of atherosclerotic cardiovascular disease (ASCVD) or be at increased risk for ASCVD. ASCVD is a condition where the arteries become narrowed or blocked due to a buildup of cholesterol and fats.
    • Participants should be on standard lipid-lowering medications according to local guidelines. These medications should be optimized and stable for at least 4 weeks before the study begins.

Who cannot join the trial?

3 criteria

  • Patients with **Hypertriglyceridemia** (high levels of triglycerides in the blood) cannot participate.
  • Patients with **Cardiovascular Diseases** (diseases related to the heart and blood vessels) are excluded.
  • Patients with **Atherosclerosis** (a condition where the arteries become narrowed and hardened) are not eligible.
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Investigated drugs

Olezarsen is a medication being studied for its potential to help people with high levels of triglycerides in their blood. Triglycerides are a type of fat, and having too much of them can increase the risk of heart disease. This medication is being tested to see if it can lower triglyceride levels in people who already have heart disease or are at risk of developing it, as well as in those with very high triglyceride levels. The goal of the study is to find out if olezarsen can effectively reduce these fat levels in the blood, which might help in managing or preventing heart-related health issues.

What is already known about the treatment

Olezarsen – Olezarsen is administered through injections, typically under the skin, and is currently being studied in a Phase 3 clinical trial. It is being investigated for its potential to help people with high levels of triglycerides in their blood, which can lead to heart diseases and hardening of the arteries. The medication works by targeting specific molecules in the body to reduce triglyceride levels, which are a type of fat found in the blood. Olezarsen belongs to a class of drugs known as antisense oligonucleotides, which are designed to interfere with the production of proteins that contribute to disease.

Investigated diseases

  • Hypertriglyceridemia

    Hypertriglyceridemia is a condition characterized by elevated levels of triglycerides in the blood. Triglycerides are a type of fat that the body uses for energy. When their levels are too high, it can lead to the thickening of artery walls, which may contribute to cardiovascular issues. Over time, this condition can cause the buildup of fatty deposits in the arteries, known as atherosclerosis. It often progresses without noticeable symptoms, making regular monitoring important. Lifestyle factors such as diet and exercise can influence triglyceride levels.

  • Cardiovascular Diseases

    Cardiovascular diseases encompass a range of conditions affecting the heart and blood vessels. These diseases often involve narrowed or blocked blood vessels, which can lead to heart attacks, chest pain, or strokes. The progression of cardiovascular diseases can be gradual, with plaque buildup in the arteries over time. This plaque can harden and narrow the arteries, reducing blood flow to the heart or brain. Risk factors include high blood pressure, high cholesterol, smoking, and diabetes. The condition can remain asymptomatic until significant artery blockage occurs.

  • Atherosclerosis

    Atherosclerosis is a disease in which plaque builds up inside the arteries. This plaque is made up of fat, cholesterol, calcium, and other substances found in the blood. Over time, the plaque hardens and narrows the arteries, limiting the flow of oxygen-rich blood to organs and other parts of the body. The progression of atherosclerosis can lead to serious problems, including heart attack, stroke, or even death. It often develops slowly and can start in childhood, progressing as people age. Factors such as high cholesterol, high blood pressure, and smoking can accelerate its development.

Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2022-503022-13-00Protocol codeISIS 678354-CS9Estimated enrolment1 490 patientsSponsorIonis Pharmaceuticals Inc.

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