Research and Development

At Alexion, we know that fighting rare diseases requires persistence, dedication, and a relentless pursuit of the highest levels of medical innovation. Our research and development programs aim to deliver life-changing therapies that bring hope to patients and families affected by rare diseases. Often, these patients have few, if any, effective treatment options and face devastating and life-threatening consequences.

Alexion pioneered the complex field of complement biology, and today our internal research efforts focus on leveraging our 20+ years of experience in this field. We discovered and developed the world’s first complement inhibitor for the treatment of life-threatening, ultra-rare disorders caused by uncontrolled complement activation. We used this deep expertise to build upon that foundation and develop the first and only long-acting C5 inhibitor. In addition, we will continue to pursue novel molecules and targets in the complement cascade.

Alexion’s development efforts focus on the core therapeutic areas of hematology and nephrology, neurology, metabolics and FcRn. We are working to expand into new complement indications and strengthen our clinical-stage pipeline through internal and external development opportunities in our four core areas.

As we develop and deliver life-changing therapies, we are also leveraging a proprietary bioinformatics platform to strengthen our understanding of rare diseases and provide insights into their epidemiology.


The complement system is a complex branch of the body’s immune system that destroys and removes foreign particles. While the complement system is essential to maintaining health, it can also become over-activated, contributing to the development of numerous devastating diseases. In PNH, for example, a genetic error in cell proteins results in a deficiency in complement inhibitors that normally protect red blood cells. PNH red blood cells are then recognized by the immune system as foreign particles, and are destroyed by complement. In aHUS, healthy tissue is attacked when complement is activated inappropriately or excessively. In anti-acetylcholine receptor (AchR) antibody-positive MG, antibodies bind to AchR, activating the complement cascade, which leads to a localized inflammation and destruction of the muscle membrane at the neuromuscular junction (NMJ), in turn leading to a loss of normal muscle function.

Our Clinical trials

Clinical trials are a critical part of our efforts to develop innovative new therapies for patients with severe and devastating rare diseases. Alexion has ongoing and actively recruiting clinical trials in a wide range of therapeutic areas.

Our Pipeline

Learn more about our global R&D organization's rare disease pipeline

View Current Pipeline

Our Trials

Learn more about some of our key ongoing clinical trials


Get information on all of our clinical trials


Voluntary Data Sharing

Alexion is indebted to patients and their families for their participation in clinical studies that help to advance treatments. As an organization, we are committed to voluntary sharing of Alexion-sponsored clinical trial data to address unmet medical/clinical needs.

Qualified academic investigators may submit a research proposal for access to clinical data and applicable supporting documents pertaining to Alexion-sponsored interventional clinical studies considered in scope.

Our online portal to receive and review academic research proposals is currently under construction. If you would like additional information, please click the link below and fill out our medical information inquiry form.

Medical Information Inquiry Form

Externally Sponsored Research

Alexion is committed to collaborating with researchers on innovative projects that advance medical and scientific knowledge about our products, product candidates and therapeutic areas of interest. Alexion’s Externally Sponsored Research includes Investigator Sponsored Research and Externally Sponsored Collaborations.

Externally Sponsored Research

Alexion encourages communication of innovative ideas in rare diseases. Applications for support or collaboration for basic research are accepted from individuals or groups, as either concepts or protocols.

Discovery Partnerships