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BMN 331 is an investigational, AAV5-based, gene therapy in development for treatment of hereditary angioedema (HAE) and the third gene therapy candidate in BioMarin’s product portfolio.

HAE is a rare genetic disorder characterized by spontaneous swelling that can be life-threatening by blocking airways and preventing breathing. The main type of HAE is caused by mutations in the SERPING1 gene. This gene encodes a protein called C1-INH* which plays an important role in controlling certain types of swelling in the body. When C1-INH is missing or not working correctly, sudden, unexpected swelling events can occur.

BMN 331 research takes a new approach and aims to prevent these swelling attacks with a one-time gene therapy treatment that is being researched to see if it can introduce the SERPING1 gene into the body, the safety profile, and whether it can enable individuals to produce their own functional C1-INH protein.

BioMarin is a leader in researching and manufacturing gene therapy and is already investigating treatments similar to BMN 331 for hemophilia A and phenylketonuria. We’re excited to leverage this experience on our journey to research and develop bring a potential new treatment option for individuals with HAE. Please note that BMN 331 is currently under investigation; the safety and efficacy in humans has not yet been determined.

*C1 esterase inhibitor (C1-INH) is a protein found in the fluid part of the blood. It controls a protein called C1, which is part of the complement system.

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