Redemplo (plozasiran)
An approved treatment for Familial Chylomicronemia Syndrome.
The same compound appears under different names depending on the context. Here is how to identify Plozasiran wherever you encounter it, plus the key facts at a glance.
- Generic name
- Plozasiran
- Brand name
- Redemplo
- Development code
- ARO-APOC3
- Drug class
- ApoC-III-directed small interfering RNA (siRNA)
- Manufacturer
- Arrowhead Pharmaceuticals
- How it's taken
- The dose is 25 mg injected under the skin once every 3 months from a single-dose pre-filled syringe, into the front of the thigh or the belly, or the outer upper arm if a caregiver or healthcare provider gives it.
An injection under the skin given once every 3 months, approved by the FDA on November 18, 2025 to lower triglycerides in adults with familial chylomicronemia syndrome (FCS), used together with a very low-fat diet. In its main trial, median triglycerides fell 80% on plozasiran against 17% on placebo at 10 months. It is Arrowhead Pharmaceuticals' first FDA-approved medicine.
Where Plozasiran fits
The second FDA-approved medicine for FCS, after olezarsen (Tryngolza) in December 2024. Both lower apoC-III; plozasiran is given every 3 months and olezarsen monthly, and no head-to-head trial has compared them.
How Plozasiran works
In FCS, the body cannot properly clear triglyceride-rich particles from the blood, so triglycerides can reach 10 to 100 times the normal level and cause pancreatitis. ApoC-III, a protein made in the liver, raises triglycerides by slowing their breakdown and clearance. Plozasiran is a small interfering RNA with sugar tags that deliver it to liver cells, where it destroys the instruction molecule (mRNA) for apoC-III through RNA interference. In the main trial, apoC-III levels were 82% to 93% lower than on placebo at different points during the year, and triglycerides dropped with them.
Mechanism: Small interfering RNA (siRNA) that silences the gene for apolipoprotein C-III (apoC-III) in the liver, speeding the clearance of triglycerides
Side effects and safety
- No routine lab monitoring is required by the label
- The label reports rises in blood sugar and HbA1c, so ask your doctor how often to check them, especially if you have diabetes
Redemplo has no boxed warning, no contraindications and no warnings section in its label. In the main trial the most common side effects, against placebo, were high blood sugar (20% against 8%), headache (16% against 8%), nausea (14% against 8%) and injection site reactions (10% against 4%). Among people without diabetes at the start, 40% on the 25 mg dose developed signs of high blood sugar against 20% on placebo, and average HbA1c rose by up to 0.36 percentage points. LDL cholesterol rose, though the average stayed under 50 mg/dL at 12 months, and liver enzymes rose slightly within the normal range. Side effects led 6% to stop, for high blood sugar or hives, against none on placebo[1].
This is not a complete list of side effects. Talk to your doctor or pharmacist about what to expect and when to seek medical attention.
Taking Plozasiran
The dose is 25 mg injected under the skin once every 3 months from a single-dose pre-filled syringe, into the front of the thigh or the belly, or the outer upper arm if a caregiver or healthcare provider gives it. It is used with a low-fat diet of 20 g of fat or less a day. Patients or caregivers are trained before the first injection. Avoid skin that is tender, bruised, red, hard, scarred or stretch-marked. If a dose is missed, give it as soon as possible and then every 3 months from that date. It is stored in the refrigerator and can be kept at room temperature for up to 30 days[1].
Availability and cost
Only available as the brand-name product.
Help paying for Redemplo
Pick your insurance to see which help fits. Drugmaker copay cards can't be used with Medicare, Medicaid or TRICARE; charity funds are the usual route there.
- Copay help
Rely On Redemplo Copay Card Program: eligible commercially insured patients may pay as little as $0 out of pocket for Redemplo 25 mg. Eligibility requirements and terms and conditions apply.
For: private insurance · source - Insurance and case manager help
A Redemplo Care Coordinator reviews insurance benefits and out-of-pocket costs, helps with approvals and appeals, and explains financial assistance options for eligible patients.
The official page does not say who qualifies. Ask the program. · source
Good to know: Phone is 1-844-REDEMPLO; hours Monday to Friday, 8 AM to 8 PM ET. Enrollment starts with the Redemplo Start Form from the doctor. A free-drug program for uninsured patients was not described on the page, so none is listed.
- From a charity · The Assistance FundFamilial Chylomicronemia Syndrome (FCS) fundOpen
Pays for: Copays, coinsurance, deductibles and other health-related expenses.
The foundation says: “OPEN — Accepting New Patients. TAF is currently accepting new patient enrollments for this program.”
Clinical trial results
Approval rested on PALISADE (NCT05089084), which randomized 75 adults with genetically confirmed or clinically diagnosed FCS and fasting triglycerides of at least 880 mg/dL to plozasiran 25 mg, 50 mg or placebo every 3 months for 12 months. At month 10, median triglycerides had fallen 80% on the approved 25 mg dose against 17% on placebo, a difference of 59%. Over 12 months, acute pancreatitis occurred in 2 people (8%) on 25 mg against 5 people (20%) on placebo[1][4].
Development history
Arrowhead Pharmaceuticals developed plozasiran under the code ARO-APOC3[5]. The FDA approved it as Redemplo on November 18, 2025 for adults with FCS[2]. It had Breakthrough Therapy, Fast Track and Orphan Drug designations and was Arrowhead's first FDA-approved medicine[3]. At the time of approval, Arrowhead said plozasiran was also in Phase 3 trials for severe hypertriglyceridemia (SHASTA-3, SHASTA-4 and SHASTA-5) and mixed hyperlipidemia (MUIR)[3].
Explore Familial Chylomicronemia Syndrome trials
Other Familial Chylomicronemia Syndrome treatments
A very low-fat diet of 20 g of fat a day or less is the foundation of FCS care. Two FDA-approved medicines can be added for adults: olezarsen (Tryngolza), a monthly injection approved in December 2024, and plozasiran (Redemplo), an injection every 3 months approved in November 2025. Both work by lowering apoC-III.
Common questions about Plozasiran
▸What is Plozasiran (Redemplo)?
An injection under the skin given once every 3 months, approved by the FDA on November 18, 2025 to lower triglycerides in adults with familial chylomicronemia syndrome (FCS), used together with a very low-fat diet. In its main trial, median triglycerides fell 80% on plozasiran against 17% on placebo at 10 months. It is Arrowhead Pharmaceuticals' first FDA-approved medicine.
▸How does Plozasiran work?
In FCS, the body cannot properly clear triglyceride-rich particles from the blood, so triglycerides can reach 10 to 100 times the normal level and cause pancreatitis. ApoC-III, a protein made in the liver, raises triglycerides by slowing their breakdown and clearance. Plozasiran is a small interfering RNA with sugar tags that deliver it to liver cells, where it destroys the instruction molecule (mRNA) for apoC-III through RNA interference. In the main trial, apoC-III levels were 82% to 93% lower than on placebo at different points during the year, and triglycerides dropped with them.
▸What are the side effects of Plozasiran?
Redemplo has no boxed warning, no contraindications and no warnings section in its label. In the main trial the most common side effects, against placebo, were high blood sugar (20% against 8%), headache (16% against 8%), nausea (14% against 8%) and injection site reactions (10% against 4%). Among people without diabetes at the start, 40% on the 25 mg dose developed signs of high blood sugar against 20% on placebo, and average HbA1c rose by up to 0.36 percentage points. LDL cholesterol rose, though the average stayed under 50 mg/dL at 12 months, and liver enzymes rose slightly within the normal range. Side effects led 6% to stop, for high blood sugar or hives, against none on placebo[1].
▸How is Plozasiran taken?
The dose is 25 mg injected under the skin once every 3 months from a single-dose pre-filled syringe, into the front of the thigh or the belly, or the outer upper arm if a caregiver or healthcare provider gives it. It is used with a low-fat diet of 20 g of fat or less a day. Patients or caregivers are trained before the first injection. Avoid skin that is tender, bruised, red, hard, scarred or stretch-marked. If a dose is missed, give it as soon as possible and then every 3 months from that date. It is stored in the refrigerator and can be kept at room temperature for up to 30 days[1].
▸Is Plozasiran FDA approved?
Yes, Plozasiran (Redemplo) is FDA approved (2025) for the treatment of Familial Chylomicronemia Syndrome.
▸How often is Redemplo given?
Once every 3 months, as a 25 mg injection under the skin from a pre-filled syringe. It can go into the thigh or belly, or the outer upper arm if a caregiver or healthcare provider gives the injection.
▸What is the difference between Redemplo and Tryngolza?
Both are FDA-approved for adults with FCS and both lower apoC-III, a liver protein that slows triglyceride clearance. Redemplo (plozasiran) is an siRNA given every 3 months, and Tryngolza (olezarsen) is an antisense medicine given monthly that is also approved for severe hypertriglyceridemia. No trial has compared them directly.
▸Does Redemplo raise blood sugar?
It can. In the PALISADE trial, high blood sugar was reported in 20% of people on plozasiran against 8% on placebo, and among people without diabetes at the start, 40% on the 25 mg dose had signs of high blood sugar against 20% on placebo. Ask your doctor how often to check your blood sugar.
Sources and references
Every factual claim on this page is drawn from the public sources listed below. Click any reference to open the original document.
- U.S. National Library of Medicine, DailyMed. REDEMPLO (plozasiran) injection, for subcutaneous use: prescribing information. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=7fd37993-f85a-4af1-8bbe-133299f226ed
- U.S. Food and Drug Administration · 2025-11-18. NDA 219947 approval letter. https://www.accessdata.fda.gov/drugsatfda_docs/appletter/2025/219947Orig1s000ltr.pdf
- Arrowhead Pharmaceuticals · 2025-11-18. Arrowhead Pharmaceuticals Announces FDA Approval of REDEMPLO (plozasiran) to Reduce Triglycerides in Adults with Familial Chylomicronemia Syndrome (FCS). https://ir.arrowheadpharma.com/news-releases/news-release-details/arrowhead-pharmaceuticals-announces-fda-approval-redemplor
- New England Journal of Medicine · 2025. Plozasiran for Managing Persistent Chylomicronemia and Pancreatitis Risk. https://www.nejm.org/doi/full/10.1056/NEJMoa2409368
- ClinicalTrials.gov. Study of ARO-APOC3 (Plozasiran) in Adults With Familial Chylomicronemia Syndrome (FCS) (PALISADE). https://clinicaltrials.gov/study/NCT05089084
- Arrowhead Pharmaceuticals. Help With Insurance: REDEMPLO (plozasiran). https://redemplo.com/access-and-support/help-with-insurance
- U.S. National Library of Medicine, DailyMed. TRYNGOLZA (olezarsen) injection, for subcutaneous use: prescribing information. https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=0f51aa8e-8475-8cf9-e063-6394a90a6848