CytoDyn Inc. (OTCQB: CYDY) (“CytoDyn” or the “Company”), a late-stage biotechnology company developing leronlimab, a CCR5 antagonist with the potential for multiple therapeutic indications, today announced a new, preclinical study in nonhuman primates that will evaluate the potential use in HIV of a gene therapy based on the experimental monoclonal antibody leronlimab.
The research will be led by Oregon Health & Science University (OHSU) researcher Jonah Sacha, Ph.D., who also serves as a CytoDyn scientific advisor. The study is funded by a five-year grant of up to $5 million to OHSU from the National Institute of Allergy and Infectious Diseases of the National Institutes of Health (NIH).
The grant will fund the development and preclinical research of a single-injection gene therapy that codes for the leronlimab protein sequence and which will be delivered via an adeno-associated virus (AAV) vector. The study will examine if this gene-therapy approach could provide the potential for “functional cure,” i.e., sustained viral suppression to people with HIV without requiring them to take medications for the rest of their lives.
Leronlimab has demonstrated it can pharmacologically mimic a CCR5 deficient donor by occupying available CCR5 molecules.1 Leronlimab is a protein, and the goal of the research at OHSU is to create a gene therapy that expresses the gene encoding the leronlimab protein. This gene therapy will also require a new delivery modality. The grant will fund the design of synthetic novel AAV vectors specific for T and B cells, with the goal of facilitating long-term expression of leronlimab by the body’s own T and B cells. A novel AAV vector may also support the future development of other anti-HIV approaches, including CRISPR-Cas9, chimeric antigen receptors, and broadly neutralizing antibodies, as it may be able to deliver these therapeutics to the relevant immune cell type. The desired outcome of this research is the development of a safe and effective single injection that suppresses HIV replication long-term, eliminating the need for frequent dosing with antiretroviral therapy.
Jacob Lalezari, M.D., Scientific Advisor to CytoDyn, stated, “The potential for a one-time gene therapy encoding a protein such as leronlimab represents a great hope for the future of HIV therapy and functional cure. Currently, cells deficient in CCR5 have demonstrated a potential path to HIV cure, and bone marrow transplant is not an option for most patients because it is risky and highly invasive. We look forward to exploring this critical area with the assistance of the NIH and advancing research with hopes of finding a functional cure and helping to end the HIV pandemic.”
Dr. Cyrus Arman, CytoDyn’s President, said, “We are honored to have the NIH’s support for a gene therapy encoding the sequence for leronlimab, and to further the research and development of leronlimab and its derivatives. Further, we are excited about the potential for this next generation approach to HIV cure.”
About HIV Functional Cure
Worldwide, nearly 38 million people live with HIV, and about 73% of them receive treatment.2 Of the 37.9 million people living with HIV around the world, approximately 23.3 million (62%) are receiving antiretroviral therapy (ART) and have the virus under control. ART therapy, however, requires regular treatment. While accessibility to testing and treatment has significantly improved worldwide, poverty, gender equality, and HIV stigma and discrimination are significant barriers to HIV prevention and treatment in many countries.3 Over half of the people living with HIV in the United States are age 50 and older, often with multiple comorbidities including liver disease, heart disease, and cancer.4 Functional cure is where the virus is still present but it is under control without the need for ongoing treatment. The CCR5 receptor remains a top target for a functional cure.
Gene therapy consisting of the gene for an anti-HIV antibody carried by an AAV vector holds promise for long-term control of HIV. Adeno-associated viruses represent a promising vector platform, mainly due to their relative safety and ability to stimulate immune responses in multiple species.5
Chang XL, Webb GM, Wu HL, Greene JM, Abdulhaqq S, Bateman KB, Reed JS, Pessoa C, Weber WC, Maier N, Chew GM, Gilbride RM, Gao L, Agnor R, Giobbi T, Torgerson J, Siess D, Burnett N, Fischer M, Shiel O, Moats C, Patterson B, Dhody K, Kelly S, Pourhassan N, Magnani DM, Smedley J, Bimber BN, Haigwood NL, Hansen SG, Brown TR, Ndhlovu LC, Sacha JB. Antibody-based CCR5 blockade protects Macaques from mucosal SHIV transmission. Nat Commun. 2021 Jun 7;12(1):3343. doi: 10.1038/s41467-021-23697-6. PMID: 34099693; PMCID: PMC8184841.