Gilead Sciences, Inc. specializes in the development, manufacturing and marketing of therapeutic products. Net sales break down by source of income as follows: - sale of drugs (99.5%): for the treatment of HIV (68.5% of net sales), oncology diseases (11.5%), hepatitis B virus (10.6%), Ebola virus (6.3%) and other (3.1%; primarily cytomegalovirus retinitis, and advanced Kaposi sarcoma resulting from HIV); - other (0.5%): especially royalties and revenue from research and development services and from subcontracted production of therapeutic products. Net sales are distributed geographically as follows: the United States (71.6%), Europe (16.1%) and other (12.3%).