Research and preclinical studies have developed an IDS2 gene that is attached to an AAV serotype 9 vector and is being injected into mice models (mice that suffer from Hunter Syndrome). The preclinical research involves injecting mice models in cohorts of ages to test the ability to stabilize or reverse effects of the disease as it progresses. Behavioral testing and other monitoring is also occurring to evaluate the effectiveness of the treatment cognitively and somatically. Early results have shown complete prevention of disease progression in pre-symptomatic mice. Additional older cohorts are currently being tested.
Prior to an IND submission to the FDA to begin a clinical trial, a GLP toxicology study must also be conducted to determine the bio-distribution and toxicity levels of the treatment. In vivo toxicology studies are intended to assess the onset, severity, and duration of toxic effects, their dose dependency and degree of reversibility (or irreversibility). Such studies, including manufacturing of the vector to test, can cost close to half a million dollars.
After completion of a GLP toxicology study, researchers design and prepare to begin a Phase I or Phase I/II clinical trial in humans. Manufacture of the vector for such a trial, as well as administration of the trial, can cost several million dollars.
Researchers often seek government funding such as NIH grants for some of these costs, but private donations, nonprofit funding, and/or licensing of the research are usually required to bring it to clinical trials.