Using DNA to Cure Viral Infections

Antiretroviral therapy (ART) drugs can increase an HIV patient’s life span considerably, but require continuous use and only restrict the virus in a latent state. Without providing a full cure, patients are prone to complications like HIV-related Dementia, and their infection can return if treatment is halted.

Excision BioTherapeutics, an Alumni Ventures Group portfolio company, has made significant breakthroughs with CRISPR-based therapies using genome editing to cure viral infections at the source. The company is developing treatments that eliminate infectious viral diseases rather than suppressing or stalling their effects, with focuses on HIV as well as Herpes, Hepatitis B, and John Cunningham Virus.

AVG first connected with Excision through Castor Ventures, the firm’s fund for MIT alums. Castor Partner, Cainon Coates, first reached out to Excision in mid-2018 and continued following the company’s impressive progress. In just four years, Excision has surpassed their seed stage research milestones and expanded their product pipeline beyond its initial HIV focus.

Eliminating Viruses at the Source

Researchers believe gene editing can help eliminate retroviruses like HIV that integrate into the genome of infected individuals. CRISPR is a series of DNA sequences that can be used to modify genes and correct mutations to prevent or eliminate diseases. Instead of merely stifling the effects of infections, gene editing can attack and eliminate viruses at the source.

Excision uses a combination of ART drugs and CRISPR-based gene editing to suppress the virus and clear HIV DNA lurking in the cells. The company’s proprietary ViraSuite platform uses algorithms to design quick and efficient gene editing therapeutics for virtually any virus. Unlike other CRISPR applications, Excision increases viral specificity and eliminates the possibility that viruses can replicate or escape the host immune system following treatment.

Excision has already demonstrated the first functional cure for HIV in animals and has preliminary data from non-human primate studies. They are one of only three companies with positive CRISPR results in animals.

The company has also established proof-of-concept using CRISPR to excise Herpes Simplex Virus, Hepatitis B virus, and John Cunningham Virus genomes from cell lines, a first step towards clinical applications. Additionally, Excision is working on advanced combinatorial DNA treatments in relation to existing Multiple Sclerosis (MS) medications.

Recognizing Significant Market Potential

Excision has also developed a robust IP portfolio across 20 countries and they have exclusively licensed newer CRISPR systems from UC Berkeley, which helps them de-risk the technology and avoid the industry’s murky business landscape. Their IP alone could already garner them a significant exit.

This is due in part to the valuation of the HIV and HSV treatment markets, set to hit $22.5B by 2024 and $2.4B by 2027, respectively. Additionally, Excision’s ability to develop therapeutics for any human virus opens up a serviceable market (including HPV, Ebola, Zika, Influenza, etc.) expected to hit $117B by 2021. The company is led by a well-rounded team of clinicians, advisors, academic

researchers, and industry veterans with the experience necessary to tackle these broader markets.

Exercising Patience and Persistence

In late 2019, Excision began raising a new round led by Norwest Venture Partners, with participation from ARTIS Ventures and other investors. Castor Partner, Cainon Coates had previously built a relationship and stayed close with the company, so he inquired about securing space in the round. The company was excited to include AVG in the round thanks to AVG’s vast alumni network. Moreover, AVG had previously invested with Norwest (a top healthcare investor) and was able to utilize the existing relationship to partner again.

Norwest and other investors have immense confidence in Excision’s potential, due to their unique IP and clinical efficacy giving rise to a favorable competitive position. Castor’s ability to access the deal stemmed from AVG’s strategies of leveraging alumni connections and investing alongside strong lead VC investors.

Our investment in the round was led by Castor Ventures along with AVG’s Chestnut Street Ventures (for Penn alums), Spike Ventures (for Stanford alums), Westwood Ventures (for UCLA alums), and Total Access Fund.