Scientists edge closer to cutting HIV out of human DNA
Scientists are nearing a breakthrough in using CRISPR gene-editing to eliminate HIV from human DNA. Early trials of EBT-101 therapy show it can safely target and cut out viral genes, offering hope for a permanent HIV cure beyond current drug treatments
Hyderabad: The day is not far away when scientists can literally cut the HIV/AIDS virus out of a patient’s cell genome. Geneticists are now very close to developing a CRISPR-based therapy that can be safely delivered throughout the body of a patient to target and edit the latent HIV reservoir, setting the stage to cure HIV.
A few months ago, a US-based company Excision BioTherapeutics presented proof-of-concept data from their CRISPR therapy, EBIT-101, and its promise to target and destroy the HIV reservoir in the human body.
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats), which is a gene-editing tool that acts like molecular scissors, allows scientists to precisely cut and modify DNA.
In this study, phase I and II clinical trials (EBT-101) tested a novel CRISPR-Cas9 gene therapy as a potential functional cure for HIV infection.
At present, there are Antiretroviral Therapies (ART), a combination of proven drugs that keep the HIV virus dormant in the human body.
The primary challenge to curing HIV is the existence of the latent reservoir of infected human cells (T-Cells) where the virus’ genetic material is kept dormant by administering patients with ART therapy. Once the patient stops the ART therapy, the dormant virus reactivates and causes rebound.
The core gene editing technology, which became the basis of the EBT 101 therapy, was developed by two US-based researchers Dr Kamel Khalili (Temple University) and Nobel laureate Dr Jennifer Doudna (UC Berkeley).
The CRISPR-Cas9 system was designed to be directly delivered to the T-Cells and other tissue reservoirs that harbour dormant HIV DNA.
Once inside the infected cell, CRISPR makes multiple cuts across the integrated HIV genome, thus permanently removing large segments of the virus DNA from the body.
The phase I and II trials, which involved a small group of participants, demonstrated that one-time IV infusion of CRISPR therapy was safe and well tolerated, with no serious side effects.
While most participants experienced viral rebound after stopping ART, one participant showed a significantly delayed viral rebound (nearly 16 weeks) and a considerable drop in the size of HIV reservoir compared to other participants in the study.
The breakthrough offered promising signals for future higher-dose applications.