MARIETTA, Ohio—ProtoKinetix, Inc. has recently announced, regarding its ongoing 3rd stage testing of retinal cell replacement therapy at the University of British Columbia, that AAGP has demonstrated the ability to protect transplanted cells in a preclinical experimental model of retinal degeneration. ProtoKinetix’s family of hyper stable, potent glycopeptides (AAGP) is said to enhance both engraftment and protection of transplanted cells, organs, tissues and organs used in regenerative medicine.
For the purpose of these tests, the animals had a functioning immune system and so were treated with immune modulating drugs to model clinical practices. The results clearly demonstrated the ability of AAGP to protect the delicate transplanted cells from the stress of the local microenvironment after transplant into the recipient at the four week timepoint.
Two questions under study have been answered — do the transplanted cells survive in the recipient and safely continue to mature into functional retinal cells? And does AAGP interfere with the fated development of the transplanted cells?
In order to find answers, a comprehensive series of tests were designed. The tests included a long-term follow-up out to six months, to determine if the cells continued to mature into photo-sensitive cells and whether the presence of AAGP interfered with this essential development. At the five month point, the tests show that AAGP preserved and allowed these cells to mature without compromise.
Pluripotent stem cell therapy guided into retinal cells could potentially cure blindness, even in the late stages of disease. But until now, studies in animals have shown that too few transplanted retinal cells survive the hostile local environment long enough to integrate correctly into the retina’s complex neural circuitry. The AAGP molecule in this study has overcome this considerable obstacle for stem cell treatments that aim to replace retinal cells.
These studies are a critical component of the preclinical testing required to advance this program into clinical trials. The study is being conducted by the Gregory-Evans Retinal Therapeutic Lab at the University of British Columbia.
“We are now completing functional studies in two different animal models. These include electrical responses of the eye and also a behavioral test of sharpness of vision,” said Dr. Kevin Gregory-Evans, professor of Ophthalmology in the Faculty of Medicine, University of British Columbia. “Preliminary results show retention of vision function particularly in behavioral testing in the rodent model. Also of note, we have not documented any adverse effects in animals when using AAGP. Although our results are in relatively small numbers of animals (a dozen in each cohort of testing), this bodes exceptionally well for any proposed future clinical trial work.”
Due to the results achieved over the last four years of testing, the University of Alberta has begun Phase 1 human clinical trials. Additional studies will be expanded to include whole organ transplantation and all therapies being developed globally to date: diabetes, retinal degeneration, cardiac repair and many other degenerative conditions. ProtoKinetix is also studying the potential impact on several cancer therapies.
