THERAPIES IN PIPELINE
To read full page, visit https://hdsa.org/hd-research/therapies-in-pipeline/
A research “pipeline” is the process of creating, testing, and ultimately approving a new drug for use in humans. HDSA funds researchers and doctors doing HD research at different stages along the pipeline, and collaborates with industry partners to bring information about clinical trials to the public. We also fund human-centric research through the HD Human Biology Project and support young scientists through the Donald King Fellowships and Berman-Topper Career Development Fellowships.
Basic research into what goes wrong in the brain in Huntington’s disease continues to provide insights into how the disease might be treated. As targets are identified, existing drugs and supplements known to address that target are reviewed and drug development efforts are instituted.
Promising drugs are tested in animal models such as drosophila (fruit flies) and mice engineered to get Huntington’s Disease. If the results are positive, a drug will be rigorously tested in one or more of the mouse models of HD. If a drug is effective and side effects are tolerable, toxicology studies are done and the drug can proceed to clinical trials.
Clinical Trials of Drugs
Once a drug is ready for testing in human patients, it must proceed through three phases of clinical trials. Phase 1 is a small trial (20-50 people with HD) testing safety. Phase 2 is a medium sized trial (50-200 people with HD) testing safety and effects of the drug on the body. Phase 3 is a large trial (200-1000 people) testing whether the drug helps with symptoms. A drug must be shown to be safe, well-tolerated, and effective before the FDA will approve it for human use.
Observational trials do not involve testing a drug – they simply look at human behavior and biology to learn more about HD, through neurological exams, cognitive tests, and blood or biosample donations. By observing and testing people with the HD gene over time and at different disease stages, researchers can discover what is changing inside the brain and body before and after the onset of HD symptoms. This is particularly important for the design of future trials that will need to measure the effectiveness of drugs before symptoms even appear.
HD family members – gene positive, at risk, gene negative, and caregivers — can volunteer to participate in an observational trial like Enroll-HD.
A Dynamic Process
Although the research pipeline appears to proceed smoothly from pre-clinical research to clinical trials, in practice it is much more dynamic. Translational researchers may need to go back to basic researchers to have questions answered. A drug may show clear signs of efficacy in preclinical testing but have serious side effects or require overly large doses to work. Depending on its potential, there may be further efforts at developing the drug. A drug that is successfully treating similar symptoms in another neurological disorder may move directly into clinical trials for HD patients. It is important for the HD community to know that Huntington’s research is going on in parallel. Basic research, translational research, and clinical trials are all in progress. There are more than two dozen drugs and supplements actively moving through the pipeline with dozens of others nominated for consideration. When one critical question is answered, efforts turn to other questions. When one drug fails, resources are quickly redirected to researching more promising ones.