We are a late-clinical stage biotechnology company focused on developing next-generation siRNA therapeutics designed to treat a broad spectrum of diseases. We are focused on advancing and expanding our pipeline of highly potent, selective and durable siRNA therapeutic candidates, including three clinical-stage programs and two advanced preclinical programs. Our goal is to control the expression of specific disease drivers with highly selective RNA targeted therapies, delivering life-changing treatments for patients with urgent unmet medical needs. Our team is united by a shared vision to build a leading next-generation siRNA therapeutics company.

siRNA, or small interfering RNA, therapeutics represent a significant advancement in precision medicine by addressing diseases at the genetic level (mRNA or RNA) while avoiding permanent alterations to a patient’s genome (DNA). While this class of medicines has had significant success both clinically and commercially, its broader potential has historically been constrained by challenges in achieving potent, durable and selective silencing, especially outside of established liver-directed applications.

Drawing on decades of RNA drug development experience, our team has built two proprietary technologies to overcome these limitations through advances in siRNA design and delivery: (1) messenger RNA (mRNA) Silencing Technology (MST) and (2) Cell Targeted Delivery (CTD). These technologies are collectively designed to optimize our siRNA sequences and delivery to both hepatic and extrahepatic tissues. Using these technologies, we seek to develop novel therapeutics prioritizing chronic diseases where deep, durable target suppression can enable meaningful clinical benefit for patients with significant unmet need. We currently have five wholly-owned therapeutic candidates in clinical and preclinical development. Our three clinical-stage therapeutic candidates, each of which targets hepatic tissues, are being evaluated for the treatment of complement-mediated diseases, hereditary angioedema (HAE) and thrombotic diseases. In addition, we are utilizing our CTD technology to expand beyond hepatic delivery into extrahepatic tissues, with two programs in or advancing to the investigational new drug application (IND)-enabling stage targeting adipose (obesity) and neurons (neurodegenerative diseases including Alzheimer’s).

Beyond our wholly-owned pipeline, in May 2025, we entered into a discovery-stage Collaboration and License Option Agreement (the AbbVie Agreement) with AbbVie to advance novel siRNA therapeutics across multiple therapeutic areas, pursuant to which we received an upfront cash payment of $335.0 million and are eligible to receive additional payments of up to $385.0 million in option extension and option exercise payments, up to $7.45 billion in additional contingent milestone payments, as well as tiered royalties at rates in the high single digits to mid-teens, as more fully described in the section titled “Business—Collaboration and license option agreement.”