The NEULARK Study at INWR: LRRK2-Driven Parkinson's and Precision Medicine in 2026
By Michael Dauer, MS, MBA
Research Director, Inland Northwest Research
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For the nearly one million people in the United States living with Parkinson's disease, and the roughly 90,000 Americans newly diagnosed each year, the central unmet need in this field has long been the same: there is no approved therapy that slows the underlying disease. Every current Parkinson's medication, including levodopa, dopamine agonists, MAO-B inhibitors, and others, is designed to manage symptoms. None changes the trajectory of the disease itself.
In 2026, a new generation of research is attempting to change that, and one of the most closely watched efforts is built on an idea borrowed from oncology: precision medicine. Rather than treating all people with Parkinson's as a single group, these studies begin by identifying a biologically-defined subset of the population — people whose disease is driven by a specific, measurable mechanism — and then testing a therapy designed to target that mechanism specifically.
At Inland Northwest Research (INWR), we are currently enrolling participants for NEULARK, a Phase 2 study that applies this approach to Parkinson's disease for the first time in a large randomized trial.
The Science of 2026: Why Genetics Are Changing Parkinson's Research
Parkinson's disease has historically been treated as a single clinical diagnosis, but researchers have known for years that the underlying biology is heterogeneous. Some people develop Parkinson's following identifiable genetic mutations. Others develop what is called idiopathic Parkinson's — disease that arises without a known family history or an identifiable cause. Increasingly, scientists are recognizing that this traditional split obscures an important reality: a much larger share of people with "idiopathic" Parkinson's disease may have specific genetic variations that quietly contribute to their disease, even without a family history.
The LRRK2 gene illustrates this. LRRK2 stands for leucine-rich repeat kinase 2, an enzyme that normally regulates a number of cellular functions, including how cells clear abnormal proteins and manage inflammation. When LRRK2 activity is elevated, these functions are disrupted in ways that appear to drive the progression of Parkinson's disease.
Two groups of people can have elevated LRRK2 activity. The first is a small population — roughly 2% of people with Parkinson's — who carry rare, inherited mutations in the LRRK2 gene itself. The second is a much larger population. Emerging research has identified single-nucleotide polymorphisms (SNPs) —common, subtle variations in DNA near the LRRK2 gene — that are also associated with elevated LRRK2 enzyme activity. Together, these two groups may represent up to 30% of all people with Parkinson's disease.
This combined population is now referred to as having LRRK2-driven Parkinson's disease, and it is the specific group that NEULARK is designed to evaluate.
What Makes NEULARK a Different Kind of Clinical Trial
Several features of the NEULARK study mark a departure from conventional Parkinson's trial design:
It is a precision medicine trial. Eligibility is not based on clinical diagnosis alone. Participants undergo an investigational genetic test designed to identify elevated LRRK2 pathway activity, including both the rare inherited mutations and the more common SNPs. This means some individuals who have had negative genetic tests for LRRK2 in the past may still qualify for NEULARK, because the test used in this study is looking for a broader set of markers than the standard clinical assays.
It uses a digital biomarker as the primary endpoint. Rather than relying solely on traditional clinical rating scales, which require in-person visits and depend heavily on observer judgment, NEULARK incorporates a smartphone-based measurement system developed in partnership with Roche Information Solutions. The primary endpoint of the study is the change from baseline in a digital biomarker score designed to capture motor and non-motor symptoms with greater frequency and granularity than periodic clinic visits allow.
It reduces the in-person burden of participation. Part of the eligibility process — specifically, the initial genetic screening — is handled through an at-home saliva test provided in partnership with Sano Genetics. This component is designed to make initial screening more accessible for people who live far from a specialized research site.
It includes an open-label extension. After the blinded portion of the study is complete, participants who received placebo will have the opportunity to receive the investigational drug in an open-label phase, pending continued eligibility.
NEU-411 and the Rationale for LRRK2 Inhibition
NEU-411, the investigational drug being evaluated in NEULARK, is an orally administered, brain-penetrant, selective small-molecule inhibitor of LRRK2. It is taken once daily.
The rationale is direct: if overactive LRRK2 contributes to the cellular dysfunction driving Parkinson's disease in a meaningful subset of patients, then selectively reducing LRRK2 activity may slow the underlying disease process in that population. In a Phase 1 clinical trial, NEU-411 was reported to be safe and well-tolerated in more than 100 healthy volunteers over 28 days of dosing and demonstrated target engagement — measurable reduction in LRRK2 pathway activity using fluid-based biomarkers. That evidence was sufficient to advance the program into the Phase 2 NEULARK trial (ClinicalTrials.gov identifier NCT06680830), which began dosing its first participant in mid-2025.
NEULARK is designed as a randomized, double-blind, placebo-controlled study. Approximately 150 participants are being enrolled globally, randomized 1:1 to receive NEU-411 or placebo once daily for 52 weeks, followed by a brief safety follow-up. Topline data are anticipated in 2027.
It is important to be clear about what this means and does not mean. NEU-411 is investigational. It is not approved by the FDA, and whether it slows Parkinson's disease progression is precisely the question NEULARK is designed to answer. Participation carries potential risks as well as potential benefits, and no individual outcome can be guaranteed. What is established is that this is the first large randomized trial in Parkinson's disease to combine a precision-medicine eligibility approach, a brain-penetrant LRRK2-selective drug, and a digital biomarker primary endpoint — and that combination is what makes it a study worth watching, whether or not one chooses to participate.
Who the Study Is Designed For
NEULARK is specifically designed for adults ages 40 to 80 with early-stage Parkinson's disease who have not yet started long-term dopaminergic therapy such as levodopa or dopamine agonists. The study is looking for a genetically-defined subpopulation — people with LRRK2-driven Parkinson's disease — which is confirmed through the investigational genetic test.
Importantly, participants who are already enrolled and who need to start dopaminergic medication during the 52-week treatment period are permitted to do so and can continue in the study. Study design decisions like this are meant to balance the scientific need for a well-defined study population with the reality of how Parkinson's disease evolves.
Because eligibility involves a genetic screening step, the process at INWR typically unfolds in stages: initial contact and pre-screening, at-home genetic testing, and — if eligible — a formal screening visit at our Spokane clinic for medical evaluation and informed consent. Final eligibility is determined strictly according to protocol-defined criteria.
If you have been diagnosed with Parkinson's disease, are between ages 40 and 80, and have not yet started long-term dopaminergic therapy, you may be eligible for NEULARK. Contact INWR at (509) 960-2818 or contact@inwresearch.com to begin the pre-screening process.How Participation Advances the Field
NEULARK is a study whose value extends well beyond any individual participant's outcome, because the questions it is asking are foundational for the future of Parkinson's research:
Can precision medicine work in Parkinson's?
NEULARK is one of the first Phase 2 trials in Parkinson's disease to enroll based on genetic and molecular markers rather than clinical diagnosis alone. Whether this approach produces clearer results than broader trials have in the past is itself a central question for the field.
Can digital biomarkers replace or complement traditional rating scales?
The continuous, smart‐phone-based measurement used in NEULARK is designed to produce a finer-grained picture of disease progression than periodic in-clinic assessments. Whether this approach reliably detects treatment effects has implications well beyond a single study.
Can LRRK2 inhibition slow the disease?
This is the direct scientific question NEU-411 is being evaluated against. A positive result would represent the first demonstration of meaningful disease modification in Parkinson's disease. A negative or ambiguous result still produces critical data about the LRRK2 pathway, the validity of the patient-selection strategy, and the performance of the digital endpoint.
Every participant — whether they receive NEU-411 or placebo — contributes to answering these questions. That contribution is what makes clinical research possible.
About Clinical Research at Inland Northwest Research
Future Research Opportunities
Inland Northwest Research actively participates in clinical research across the full spectrum of movement disorders and neurodegenerative conditions, including Parkinson's disease, Multiple System Atrophy, Huntington's disease, Dystonia, Essential Tremor, and related conditions.
We post new research opportunities on our website only after they have received IRB approval and are formally open for enrollment. This ensures that any study we publicize has undergone independent ethical review and that participants can be properly informed and screened. We encourage patients, caregivers, and referring clinicians to check back regularly or reach out to our team directly.
Research vs. Treatment: An Important Distinction
Inland Northwest Research is a clinical trial site, not a primary care clinic. Our sister organization, Selkirk Neurology, provides established medical treatments and symptom management for Parkinson's disease and other movement disorders under the direction of Dr. Jason Aldred. INWR conducts regulated clinical studies designed to evaluate investigational drugs and devices.
In NEULARK and most other clinical trials, participants are randomized and some receive placebo as part of the study design. This is a scientifically necessary method used to determine whether an investigational treatment is safe and effective. There is no guarantee of direct medical benefit to any individual participant. Participation is entirely voluntary, and individuals may withdraw at any time without penalty or effect on their medical care.
Eligibility criteria, visit schedules, risks, and potential compensation vary by protocol. All of these details are reviewed thoroughly during the informed consent process, which occurs before any research activities begin.
How the Enrollment Process Works
For NEULARK and other studies at INWR, the enrollment process follows the same structured steps designed to protect participants and ensure the right fit between individual and protocol:
Connect. Reach out to us at (509) 960-2818 or contact@inwresearch.com.
Pre-Screen. We review medical history and basic eligibility criteria. For NEULARK, this includes an initial questionnaire and, if appropriate, an at-home saliva kit for genetic testing.
Informed Consent Review. If preliminarily eligible, you will receive a detailed informed consent form to review with family members and your treating neurologist before making any decision.
Screening Visit. If you choose to proceed, formal screening assessments are completed at our Spokane clinic.
Final eligibility is determined strictly according to protocol-defined inclusion and exclusion criteria.
For more information on NEULARK specifically, visit our Parkinson's disease research page or the study's listing on ClinicalTrials.gov (NCT06680830).