HELIOS-A: A Study of Vutrisiran (ALN-TTRSC02) in Patients With Hereditary Transthyretin Amyloidosis (hATTR Amyloidosis)

• Patisiran (Drug), also known as ONPATTRO, ALN-TTR02: Patisiran will be administered by IV infusion.
• Vutrisiran (Drug), also known as ALN-TTRSC02, AMVUTTRA: Vutrisiran will be administered by SC injection.

Primary outcomes

• Change From Baseline in the Modified Neurologic Impairment Score +7 (mNIS+7) at Month 9 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] [Baseline, Month 9]: The mNIS+7 is a composite score that measures neurologic impairment which includes the following components: physical exam of lower limbs, upper limbs and cranial nerves to assess motor strength/weakness, electrophysiologic measurement of small and large nerve fiber function, sensory testing and postural blood pressure. The mNIS+7 is scored from 0 (no impairment) to 304 points (maximum impairment). A higher score indicates a worse outcome.

Secondary outcomes

• Change From Baseline in Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QoL-DN) Total Score at Month 9 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] [Baseline, Month 9]: The Norfolk QoL-DN questionnaire is a standardized 35-item patient-reported outcomes measure that is sensitive to the different features of diabetic neuropathy - small fiber, large fiber, and autonomic nerve function. The total score ranges from -4 (best possible quality of life) to 136 points (worst possible quality of life). A higher score indicates a worse outcome.
• Change From Baseline in the Timed 10-Meter Walk Test (10-MWT) at Month 9 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] [Baseline, Month 9]: The 10-MWT is a measure of ambulatory ability and measures the time (in seconds) that it takes a participant to walk 10 meters (gait speed). An increase in gait speed from baseline represents improvement, and a decrease from baseline represents worsening.
• Change From Baseline in the Modified Neurologic Impairment Score +7 (mNIS+7) at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] [Baseline, Month 18]: The mNIS+7 is a composite score that quantifies motor, sensory, and autonomic neurologic impairment due to injury of large and small nerves. The mNIS+7 is scored from 0 (no impairment) to 304 points (maximum impairment). A higher score indicates a worse outcome.
• Change From Baseline in Norfolk QoL-DN Total Score at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] [Baseline, Month 18]: The Norfolk QoL-DN questionnaire is a standardized 35-item patient-reported outcomes measure that is sensitive to the different features of diabetic neuropathy - small fiber, large fiber, and autonomic nerve function. The total score ranges from -4 (best possible quality of life) to 136 points (worst possible quality of life). A higher score indicates a worse outcome.
• Change From Baseline in the 10-MWT at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] [Baseline, Month 18]: The 10-MWT is a measure of ambulatory ability and measures the time (in seconds) that it takes a participant to walk 10 meters (gait speed). An increase in gait speed from baseline represents improvement, and a decrease from baseline represents worsening.
• Change From Baseline in the Modified Body Mass Index (mBMI) at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] [Baseline, Month 18]: The mBMI, which is a measure of nutritional status, is calculated as the product of body mass index (BMI) (weight in kilograms divided by the square of height in meters) and serum albumin (g/L) to reflect fluid balance, such as fluid accumulation or dehydration. A negative change from baseline indicates a better outcome.
• Change From Baseline in the Rasch-Built Overall Disability Scale (R-ODS) at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] [Baseline, Month 18]: The R-ODS is a patient-reported measure of level of disability on a scale of 0-48, with 0 being the worst and 48 the best (no limitations); scores are based on activities of daily living and social participation. An increase in R-ODS from baseline suggests improvement in disability, and a decrease from baseline suggests worsening of disability.
• Percent Reduction in Serum Transthyretin (TTR) Levels Through Month 18 Between the Vutrisiran Group (HELIOS-A) and the Patisiran Group (HELIOS-A) [Up to Month 18]: Serum TTR was assessed at multiple timepoints up to Month 18.

Sex: All, ages: 18 Years to 85 Years

Inclusion Criteria:

* Male or female of 18 to 85 years of age (inclusive);
* Has a diagnosis of hATTR amyloidosis with transthyretin (TTR) mutation;
* Has adequate neurologic impairment score (NIS);
* Has adequate polyneuropathy disability (PND) score;
* Has adequate Karnofsky Performance Status (KPS).

Exclusion Criteria:

* Had a prior liver transplant or is likely to undergo liver transplantation during the study;
* Has known other (non-hATTR) forms of amyloidosis or leptomeningeal amyloidosis;
* Has New York Heart Association heart failure classification >2;
* Clinically significant liver function test abnormalities;
* Has known human immunodeficiency virus (HIV), hepatitis C virus (HCV) or hepatitis B virus (HBV) infection;
* Received an experimental drug within 30 days of dosing;
* Received prior TTR-lowering treatment;
* Has other known causes of neuropathy.

Participant flow

Outcome results

• Change From Baseline in the Modified Neurologic Impairment Score +7 (mNIS+7) at Month 9 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] (Primary), Least squares mean, score on a scale: External Placebo Comparator (APOLLO) 14.76 +/- 2.00; Vutrisiran + Vutrisiran (HELIOS-A) -2.24 +/- 1.43 (p <0.0000001)
• Change From Baseline in Norfolk Quality of Life-Diabetic Neuropathy (Norfolk QoL-DN) Total Score at Month 9 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] (Secondary), Least squares mean, score on a scale: External Placebo Comparator (APOLLO) 12.9 +/- 2.2; Vutrisiran + Vutrisiran (HELIOS-A) -3.3 +/- 1.7 (p <0.0000001)
• Change From Baseline in the Timed 10-Meter Walk Test (10-MWT) at Month 9 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] (Secondary), Least squares mean, m/sec: External Placebo Comparator (APOLLO) -0.133 +/- 0.025; Vutrisiran + Vutrisiran (HELIOS-A) -0.001 +/- 0.019 (p <0.0000001)
• Change From Baseline in the Modified Neurologic Impairment Score +7 (mNIS+7) at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] (Secondary)
• Change From Baseline in Norfolk QoL-DN Total Score at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] (Secondary)
• Change From Baseline in the 10-MWT at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] (Secondary)
• Change From Baseline in the Modified Body Mass Index (mBMI) at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] (Secondary)
• Change From Baseline in the Rasch-Built Overall Disability Scale (R-ODS) at Month 18 Between the Vutrisiran Group (HELIOS-A) and the External Placebo Comparator Group [APOLLO (NCT01960348)] (Secondary)
• Percent Reduction in Serum Transthyretin (TTR) Levels Through Month 18 Between the Vutrisiran Group (HELIOS-A) and the Patisiran Group (HELIOS-A) (Secondary)

Adverse events

Time frame: Non-serious AEs from first dose of study drug through Month 9. SAEs from signing of informed consent through Month 9.

Serious adverse events by term

Other adverse events by term

• Results publication: Cauquil C, Adams D, Gillmore J, Gonzalez-Duarte A, Mezei M, Obici L, Sekijima Y, Zhao W, Boyle K, Badri P, Sweetser M, Moffitt C, Waddington-Cruz M. Long-term efficacy and safety of vutrisiran in hereditary transthyretin amyloidosis with polyneuropathy: final analysis of the HELIOS-A randomized treatment extension. Amyloid. 2026 Jun 15:1-12. doi: 10.1080/13506129.2026.2685666. Online ahead of print. PMID 42290201
• Results publication: Luigetti M, Quan D, Berk JL, Conceicao I, Misumi Y, Chao CC, Bender S, Aldinc E, Vest J, Adams D. Impact of Baseline Neuropathy Severity on Vutrisiran Treatment Response in the Phase 3 HELIOS-A Study. Neurol Ther. 2024 Jun;13(3):625-639. doi: 10.1007/s40120-024-00595-9. Epub 2024 Mar 21. PMID 38512694
• Results publication: Obici L, Ajroud-Driss S, Lin KP, Berk JL, Gillmore JD, Kale P, Koike H, Danese D, Aldinc E, Chen C, Vest J, Adams D; HELIOS-A Collaborators Study Group. Impact of Vutrisiran on Quality of Life and Physical Function in Patients with Hereditary Transthyretin-Mediated Amyloidosis with Polyneuropathy. Neurol Ther. 2023 Oct;12(5):1759-1775. doi: 10.1007/s40120-023-00522-4. Epub 2023 Jul 31. PMID 37523143
• Results publication: Adams D, Tournev IL, Taylor MS, Coelho T, Plante-Bordeneuve V, Berk JL, Gonzalez-Duarte A, Gillmore JD, Low SC, Sekijima Y, Obici L, Chen C, Badri P, Arum SM, Vest J, Polydefkis M; HELIOS-A Collaborators. Efficacy and safety of vutrisiran for patients with hereditary transthyretin-mediated amyloidosis with polyneuropathy: a randomized clinical trial. Amyloid. 2023 Mar;30(1):1-9. doi: 10.1080/13506129.2022.2091985. Epub 2022 Jul 23. PMID 35875890

• Study Protocol (PDF, 2021-02-19)
• Statistical Analysis Plan (PDF, 2021-08-24)

• Medical Director, Study director, Alnylam Pharmaceuticals

NIH grants: 2018, 2023