Despite therapeutic advances, human immunodeficiency virus (HIV) is still a pervasive disease, with approximately 37 million people infected worldwide. Peptides have become popular therapeutic agents, as these proteins offer structural diversity for many different diseases. Several peptides were commercially developed as HIV therapeutics, demonstrating the high potential for peptides in treating HIV. 

Researchers at the National Cancer Institute developed a novel small polypeptide, known as SD1, for use as an HIV therapeutic. SD1 is derived from scytovirin, a potent anti-HIV protein isolated from the cyanobacterium Scytonema varium. SD1 has demonstrated low nanomolar activity against laboratory HIV strains and inhibits HIV by blocking viral fusion. SD1 is a lectin with specificity for viral envelope glycoproteins. 

Competitive Advantages:

• Small size allows for decreased immunogenicity
• Small size allows for easy synthesis using automated techniques
• Low nanomolar activity against HIV strains
• Possible activity against additional viruses due to its ability to target viral envelope glycoproteins through a lectin mechanism

Commercial Applications:

• Anti-HIV microbicide
• Anti-HIV therapeutic