Regeneron Pharmaceuticals, Inc. is an American biotechnology company headquartered in Tarrytown, New York. The company was founded in 1988.[4] Originally focused on neurotrophic factors and their regenerative capabilities (thus the name), it branched out into the study of both cytokine and tyrosine kinase receptors.

Neurotrophic factors (NTFs) are a family of biomolecules – nearly all of which are peptides or small proteins – that support the growth, survival, and differentiation of both developing and mature neurons

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