What Sirius Therapeutics does

Sirius Therapeutics is a clinical-stage biotechnology company developing small interfering RNA (siRNA) therapeutics for chronic cardiovascular and metabolic diseases. Founded in 2021 and headquartered in San Diego with a translational medicine center in Shanghai, the company operates a hybrid US-China model that pairs U.S.-based regulatory and discovery expertise with China-based early development capacity and cost efficiency. Sirius's pipeline is built on its proprietary PEPR siRNA technology platform, which combines sequence design and screening, chemical modification, and GalNAc conjugate delivery systems for liver targeting. The pipeline includes four programs across three franchises: SRSD107, a Factor XI-targeting siRNA in Phase 2 for thromboembolic disorders; SRSD216, an Lp(a)-targeting siRNA in Phase 2 for hyperlipoproteinemia(a); SRSD101, a PCSK9-targeting siRNA in Phase 1 for dyslipidemia; and SRSD384, an INHBE-targeting preclinical candidate for obesity.

Sirius has no approved products and is pre-revenue, generating no product sales. Its economics are currently anchored by a May 2025 strategic collaboration with CRISPR Therapeutics to co-develop and co-commercialize SRSD107, under which Sirius received a $95 million upfront payment and is eligible for over $800 million in development and commercial milestones, with 50-50 cost and profit sharing (CRISPR leads U.S. commercialization, Sirius leads Greater China). CRISPR also holds options on up to two additional siRNA programs. The company has raised nearly $150 million in venture funding across a Series A (2021), a $60 million Series B (October 2023, led by Hankang Capital), and a nearly $50 million Series B2 (May 2025, led by BioTrack Capital). Going to market will follow standard pharmaceutical distribution upon regulatory approval, with the CRISPR collaboration covering the U.S. channel and Sirius retaining direct commercialization rights in Greater China.

The intended end markets are large, chronic disease populations: patients with thromboembolic disorders (where SRSD107 demonstrated over 93% FXI reduction sustained for six months), hyperlipoproteinemia(a) (where SRSD216 demonstrated up to 94.7% Lp(a) reduction with effects persisting beyond 90% inhibition at seven months), dyslipidemia, and obesity. Sirius's core differentiator is the potential for infrequent dosing (semi-annual or annual subcutaneous administration), which addresses compliance and adherence limitations of existing chronic cardiovascular therapies. Clinical development is global, with active or completed regulatory clearances from the FDA, NMPA, and EMA, and trial sites spanning the U.S., China, Europe, and Australia.

Name

Sirius Therapeutics

Legal name

Sirius Therapeutics, Inc.

Website

https://siriusrna.com

Company type

Private

Founded year

2021

Operating status

Operating

Headcount range

11–50 employees

Short description

Sirius Therapeutics is a clinical-stage biotech developing siRNA therapeutics for chronic cardiovascular, cardiometabolic, and metabolic diseases using its proprietary PEPR platform and GalNAc liver-targeted delivery. It is pre-revenue, with lead programs SRSD107 (FXI) and SRSD216 (Lp(a)) in Phase 2.

Ownership category

akta.pro rank

Product category

RNAi Therapeutics

NAICS

Research and Development in Biotechnology (except Nanobiotechnology) (541714), Biological Product (except Diagnostic) Manufacturing (325414)

SIC

Biological Products, (No Disgnostic Substances) (2836), Services-Commercial Physical & Biological Research (8731)

akta.pro primary industry

siRNA Therapeutics (gene silencing) (HLAAADAB)

akta.pro secondary industries

RNA Therapeutics Platforms & Design (sequence design, target ID/validation, AI/bioinformatics) (HLAAADAG), RNA Therapeutics Clinical Development (trial design, endpoints, patient stratification) (HLAAADAH), RNA Chemistry & Oligonucleotide Engineering (backbones, modifications, stereochemistry) (HLAAADAE), RNA Manufacturing & CMC (oligo synthesis, IVT, purification, formulation, QC) (HLAAADAF)

Keywords

• RNAi therapeutics
• SiRNA drug development
• Cardiovascular biotechnology
• Anticoagulant therapies
• Cardiometabolic drug discovery

Headquarters

HQ city

San Diego

HQ country

United States

HQ region

North America

Offices2 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Technology or R&D, Personnel, Operations, Infrastructure, Marketing or Sales

Revenue model

1. siRNA Therapeutics Development and Commercialization: Pre-revenue clinical-stage biotech company developing siRNA therapeutics for chronic diseases. Revenue expected upon regulatory approval and commercialization of pipeline products including SRSD107, SRSD216, and SRSD101. Strategic co-development and profit-sharing partnership with CRISPR Therapeutics.

Go-to-market motion1 record

Distribution channels1 record

Marketing channels3 records

Core offering

Sirius Therapeutics is a clinical-stage biotechnology company developing novel small interfering RNA (siRNA) therapeutics for chronic cardiovascular, cardiometabolic, and metabolic diseases. Its lead candidates include SRSD107 (Factor XI inhibitor for thromboembolic disorders, Phase 2), SRSD216 (Lp(a) reducer for atherosclerotic cardiovascular disease, Phase 2), SRSD101 (PCSK9 inhibitor for dyslipidemia, Phase 1), and SRSD384 (INHBE inhibitor for obesity). The company operates a hybrid US-China model combining U.S. discovery and regulatory expertise with China-based early development and is partnered with CRISPR Therapeutics for SRSD107.

Product overview

Sirius Therapeutics is a clinical-stage biotech company developing novel siRNA (small interfering RNA) therapeutics for chronic diseases. The company's pipeline is organized around three key franchises: coagulation disorders (SRSD107), cardiometabolic diseases (SRSD216, SRSD101), and obesity (SRSD384). SRSD107 is a FXI inhibitor co-developed with CRISPR Therapeutics for anticoagulation, currently in Phase 2. SRSD216 targets elevated Lp(a) for cardiovascular disease, in Phase 2. SRSD101 addresses dyslipidemia via PCSK9 targeting, in Phase 1. SRSD384 targets INHBE for obesity management, in preclinical stage. The company operates with a hybrid US-China model combining early development capacity with global regulatory expertise.

Differentiator

Problem solved

Functional benefit

Products and services

• SRSD107 A next-generation, long-acting siRNA therapeutic targeting coagulation Factor XI (FXI) for the prevention and treatment of thromboembolic disorders. Designed for potential twice-yearly subcutaneous administration with reversible effects. In Phase 2 clinical development and being co-developed with CRISPR Therapeutics.
• SRSD216 An siRNA therapeutic targeting lipoprotein(a) synthesis for the treatment of hyperlipoproteinemia(a) and atherosclerotic cardiovascular disease (ASCVD). Demonstrated up to 94.7% reduction in Lp(a) levels with greater than 90% inhibition maintained at 7 months in Phase 1 trials. In Phase 2 clinical development.
• SRSD101 A PCSK9-targeting siRNA therapeutic for the treatment of dyslipidemia, designed to lower LDL-C by enhancing hepatic LDL-C receptor uptake. Currently in Phase 1 clinical development.
• SRSD384 An INHBE (inhibin beta E) inhibitor siRNA therapeutic for managing obesity and related metabolic conditions, expected to enter Phase 1 clinical development in mid-2026.

Quantifiable outcome

• SRSD107: Over 93% reduction in FXI levels with effects sustained for up to six months; >100% increase in aPTT (thromboplastin time); Phase 2 ongoing for VTE and chronic CAD/PAD
• +1 more outcomes

Segments3 records

Ideal customer profiles4 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature3 records

Partnerships

One partnership is on record.

• CRISPR TherapeuticscoreStrategic or Co-development Partner · 20 May 2025Strategic collaboration to develop and commercialize siRNA therapies for thromboembolic disorders and other serious diseases. Lead program SRSD107 is a long-acting Factor XI siRNA. Sirius received $95 million upfront payment and is eligible for over $800 million in milestones. 50-50 cost and profit sharing. CRISPR leads U.S. commercialization, Sirius leads Greater China. CRISPR has option to license up to two additional siRNA programs.

Scale indicators5 records

Recent moves10 records

Expansion highlights5 records

Direct peers

• Alnylam Pharmaceuticals: The pioneer and global leader in RNAi therapeutics with approved siRNA products (Onpattro, Givlaari, Oxlumo, Amvuttra) and a GalNAc conjugate delivery platform. Direct comparable to Sirius given shared siRNA modality, GalNAc liver targeting, and chronic disease focus including cardiovascular and metabolic indications.
• Arrowhead Pharmaceuticals: Clinical-stage RNAi company with the TRiM platform and broad pipeline across cardiometabolic, liver, and pulmonary diseases. Curt Bradshaw, Sirius's CSO, was previously CSO at Arrowhead, and both companies pursue liver-targeted GalNAc-siRNA strategies against overlapping targets.
• Silence Therapeutics: Clinical-stage siRNA company developing SLN360 (Lp(a)) and other cardiovascular and hematology assets using GalNAc-conjugated siRNA. Directly comparable to Sirius given shared siRNA modality, target overlap (Lp(a)), and similar clinical-stage maturity.

Broad incumbents

• Ionis Pharmaceuticals: Established leader in antisense oligonucleotide (ASO) therapeutics with multiple approved products and a deep cardiovascular and metabolic pipeline (including pelacarsen for Lp(a) partnered with Novartis). Comparable to Sirius as a fellow RNA-targeted therapeutics company pursuing the same cardiometabolic indications via a different oligonucleotide modality.
• Dicerna Pharmaceuticals (Novo Nordisk): siRNA therapeutics company acquired by Novo Nordisk in 2021 for US$3.3 billion. Douglas Fambrough, Sirius's Independent Director, founded and led Dicerna. Highly comparable siRNA GalNAc platform with overlapping cardiometabolic and rare disease focus, now operating within Novo Nordisk's broader pipeline.
• Amgen: Large-cap biotech developing olpasiran, a GalNAc-conjugated siRNA targeting Lp(a), in Phase 3. Direct competitive comparable to Sirius's SRSD216 program in the same indication with similar mechanism and dosing ambitions.
• Novartis: Large pharmaceutical company with pelacarsen (ASO targeting Lp(a), partnered with Ionis) in Phase 3 development for cardiovascular risk reduction. Directly competitive to Sirius's SRSD216 program on Lp(a) reduction despite different oligonucleotide modality.

Emerging players

• Wave Life Sciences: Clinical-stage RNA therapeutics company with PRISM platform for stereopure oligonucleotides, pursuing cardiometabolic and rare disease indications. Comparable to Sirius as a fellow next-generation RNA therapeutics platform company targeting overlapping chronic disease areas.
• Intellia Therapeutics: Clinical-stage gene editing company using CRISPR/Cas9 with a focus on cardiometabolic and rare diseases (including transthyretin amyloidosis and hereditary angioedema). Comparable to Sirius as a fellow nucleic acid-based therapeutic company with overlapping target areas and chronic-disease positioning.
• Verve Therapeutics: Clinical-stage cardiovascular company developing in vivo base-editing therapies targeting PCSK9, Lp(a), and ANGPTL3. Comparable to Sirius as a fellow cardiovascular-focused nucleic acid therapeutics company pursuing similar lipid and cardiometabolic targets through a different but related modality.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks6 records

Key highlights7 records

Customer concentration

• LinkedInlinkedin.com/company/sirius-therapeutics-inc

Revenue estimate

Valuation estimate

Number of profiles

Profiles9 records

Funding overview

Funding rounds2 records

Investors5 records

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Sirius Therapeutics