Adeno-associated virus serotype 9 (AAV9): tool of gene therapy that crosses the BBB

Adeno-associated virus serotype 9 (AAV9) is highly valued in gene therapy because it can cross the blood-brain barrier. It is primarily used to treat monogenic neurological and neuromuscular disorders, most notably Spinal Muscular Atrophy (SMA).

AAV9 vectors deliver functional genetic material to replace or suppress faulty genes. Approved treatments and advanced clinical trials using AAV9 include:

Spinal Muscular Atrophy (SMA): The FDA-approved therapy Zolgensma (onasemnogene abeparvovec-xioi) uses AAV9 to deliver a functional copy of the SMN1 gene to motor neurons in children under two years old.

Pompe’s Disease: AAV9 gene therapies are in late-stage clinical development to deliver a working GAA gene to infants and patients, improving motor function and cardiac outcomes.

GM1 Gangliosidosis: Intravenous AAV9 gene therapy is in clinical trials (such as AAV9-GLB1) to address the central nervous system degeneration and enzyme deficiency in this rare lysosomal storage disease.

Other Neurological & Rare Diseases: AAV9 is actively being investigated in clinical trials for conditions such as Giant Axonal Neuropathy, Rett Syndrome, Friedreich’s Ataxia, and CLN7 Batten Disease.

HEOR Survival Statistics and Data Shading

𝐖𝐡𝐞𝐧 𝐚 𝐝𝐫𝐮𝐠 𝐬𝐡𝐨𝐰𝐬 𝐚 𝐡𝐚𝐳𝐚𝐫𝐝 𝐫𝐚𝐭𝐢𝐨 𝐨𝐟 𝟎.𝟖𝟎 — 𝐰𝐡𝐢𝐜𝐡 𝐬𝐨𝐮𝐧𝐝𝐬 𝐢𝐦𝐩𝐫𝐞𝐬𝐬𝐢𝐯𝐞 — 𝐚𝐧𝐝 𝐭𝐡𝐞 𝐭𝐫𝐢𝐚𝐥 𝐦𝐞𝐝𝐢𝐚𝐧 𝐬𝐮𝐫𝐯𝐢𝐯𝐚𝐥 𝐰𝐚𝐬 𝟏𝟓 𝐦𝐨𝐧𝐭𝐡𝐬 𝐢𝐧 𝐭𝐡𝐞 𝐜𝐨𝐧𝐭𝐫𝐨𝐥 𝐚𝐫𝐦, 𝐭𝐡𝐞 𝐦𝐚𝐭𝐡 𝐰𝐨𝐫𝐤𝐬 𝐨𝐮𝐭 𝐭𝐨 𝐫𝐨𝐮𝐠𝐡𝐥𝐲 𝟑 𝐚𝐝𝐝𝐢𝐭𝐢𝐨𝐧𝐚𝐥 𝐦𝐨𝐧𝐭𝐡𝐬 𝐚𝐭 𝐭𝐡𝐞 𝐦𝐞𝐝𝐢𝐚𝐧. 𝐍𝐨𝐭 𝐲𝐞𝐚𝐫𝐬. 𝐌𝐨𝐧𝐭𝐡𝐬. 𝐒𝐨𝐦𝐞𝐭𝐢𝐦𝐞𝐬 𝐰𝐞𝐞𝐤𝐬. The drug costs $28,000/month.

If a cancer drug showed “statistically significant survival benefit” in a clinical trial, what does that mean for the patient taking it? It might mean years. It might mean weeks. “Statistically significant” means the result is unlikely to be due to chance. It says nothing about size.

When a drug shows a hazard ratio of 0.80 — which sounds impressive — and the trial median survival was 15 months in the control arm, the math works out to roughly 3 additional months at the median. Not years. Months. Sometimes weeks.

That drug will cost $28,000 a month. It will go through a formulary process in which the manufacturer submits an economic model projecting its value over a 30-year horizon. The model will show, because of the way long-term survival projections work, something that looks considerably larger than 3 months.

A job posting this week describes the consultant hired to build that model: $150 an hour, 8 months, working across clinical, medical, and market access teams to “translate clinical data into inputs for economic models.” The collaboration with the market access team is in the job description. It is not incidental.

The patient navigating prior authorization, step therapy requirements, and cost-sharing for this drug does not know that the economic model justifying its price was built by a consultant hired by the manufacturer, using methods that contain documented directional bias toward favorable framing.

They were told it showed significant survival benefit. It did. Three months at the median. The rest is construction.

The HEOR Director is told “take data from cancer drug trials and feed it into economic models that determine what the drug is worth.” 𝐇𝐞𝐫𝐞’𝐬 𝐰𝐡𝐚𝐭 𝐭𝐡𝐚𝐭 𝐚𝐜𝐭𝐮𝐚𝐥𝐥𝐲 𝐢𝐧𝐯𝐨𝐥𝐯𝐞𝐬. 𝐓𝐡𝐞 𝐝𝐫𝐮𝐠 𝐚𝐭 𝐭𝐡𝐞 𝐞𝐧𝐝 𝐨𝐟 𝐭𝐡𝐢𝐬 𝐩𝐫𝐨𝐜𝐞𝐬𝐬 𝐜𝐨𝐬𝐭𝐬 $𝟐𝟖,𝟎𝟎𝟎 𝐚 𝐦𝐨𝐧𝐭𝐡. 𝐓𝐡𝐞 𝐭𝐫𝐢𝐚𝐥 𝐬𝐡𝐨𝐰𝐞𝐝 𝟑 𝐦𝐨𝐧𝐭𝐡𝐬 𝐨𝐟 𝐦𝐞𝐝𝐢𝐚𝐧 𝐬𝐮𝐫𝐯𝐢𝐯𝐚𝐥 𝐛𝐞𝐧𝐞𝐟𝐢𝐭. 𝐓𝐡𝐞 𝐦𝐨𝐝𝐞𝐥 𝐬𝐡𝐨𝐰𝐬 𝐬𝐨𝐦𝐞𝐭𝐡𝐢𝐧𝐠 𝐭𝐡𝐚𝐭 𝐥𝐨𝐨𝐤𝐬 𝐜𝐨𝐧𝐬𝐢𝐝𝐞𝐫𝐚𝐛𝐥𝐲 𝐦𝐨𝐫𝐞 𝐢𝐦𝐩𝐫𝐞𝐬𝐬𝐢𝐯𝐞. 𝐓𝐡𝐚𝐭 𝐢𝐬 𝐰𝐡𝐚𝐭 𝐭𝐡𝐢𝐬 𝐣𝐨𝐛 𝐢𝐬 𝐟𝐨𝐫.

Cancer drug trials run for 3–5 years. Economic models that justify drug prices need to project 5–10 years into the future beyond the clinical follow-up end date, because that’s what payers require. The gap between what the trial observed and what the model projects is filled by statistical extrapolation — a mathematical technique that extends the survival curve beyond the data.

Different extrapolation methods, fitted to the same trial data, can produce radically different long-term projections. A drug that extended median survival by 3 months in a trial might look, in one model, like it extends 10-year survival by 6 percentage points — or, in a different equally valid model, by 1 percentage point. The QALY gain, and therefore the justifiable price, differs by a factor of six depending on which model gets selected.

The person being hired makes that selection. They also select how transition probabilities move patients between health states in the model, which quality-of-life weights to apply, and how to model the costs the drug allegedly saves the health system.

Each choice is defensible. The aggregate is not neutral.

National Alzheimer’s Prevention Policy

“𝐉𝐮𝐝𝐠𝐞 𝐚 𝐦𝐚𝐧 𝐛𝐲 𝐡𝐢𝐬 𝐪𝐮𝐞𝐬𝐭𝐢𝐨𝐧𝐬 𝐫𝐚𝐭𝐡𝐞𝐫 𝐭𝐡𝐚𝐧 𝐛𝐲 𝐡𝐢𝐬 𝐚𝐧𝐬𝐰𝐞𝐫𝐬.”
– 𝐕𝐨𝐥𝐭𝐚𝐢𝐫𝐞     So here’s my question: Should a national policy treat perfectly healthy, “at risk” people for Alzheimer’s before they show a single symptom?
I’ve spent the last several months researching and writing exactly that — a new national prophylaxis framework for Alzheimer’s prevention. Not early detection. Prevention before onset. [Spoiler alert: in June I will send the 1500-word policy proposal to Health Affairs]

The uncomfortable reality (why this is not academic)
Most healthcare policy waits for a diagnosis. My research flips the model: identify genetic, biomarker, or lifestyle-based risk in healthy individuals, then intervene with drugs, protocols, or monitoring.

The upside is obvious — delaying or stopping Alzheimer’s entirely. The downside is less discussed: labeling healthy people as “pre-patients,” potential over-medicalization, and a massive shift in who pays for what.
Whether you love or hate the idea, it’s coming. And that changes your industry.

The career hook (why you should care even if you hate policy)
Here’s where your job search enters the room.

A national Alzheimer’s prophylaxis policy would create entirely new roles:
• Genetic risk counselors for employers
• “Pre-diagnosis” care coordinators in insurance
• Compliance and ethics officers for at-risk data privacy
• New training specialties for geriatric nurses, data scientists, and benefits managers

If you work in health tech, HR, benefits brokerage, pharma sales, or public policy — this is a near-future skill set you can start building now. Ignoring it means competing against people who saw it coming.

What I’m actually doing with this research

I’m not just theorizing. My current writing outlines a state-level pilot framework that answers:
• Who consents for a healthy person?
• What happens if prophylaxis fails — or has side effects?
• How do employers handle “at risk” designations without discrimination?

I’ll be sharing key sections over the next few weeks. First up: the liability question that keeps corporate counsel up at night.

Voltaire was right: the right question is more revealing than any tidy answer.
My question to you — whether you’re in healthcare, tech, or just planning a 30-year career:

Are you waiting for Alzheimer’s prevention to become mainstream before you learn how it affects your job market? The framework is designed to be implementable at the primary care level — no specialist required. I practice what I preach — I’ve been following this framework myself for two years. The built-in design means that even if I was never at elevated risk, I’ve already realized measurable health and cost benefits. That’s the win-win.

Intrigued? The first installment drops next week.

 𝐒𝐮𝐩𝐩𝐥𝐞𝐦𝐞𝐧𝐭 𝐌𝐲𝐭𝐡𝐬: 𝐓𝐡𝐞 𝐓𝐫𝐮𝐭𝐡 𝐀𝐛𝐨𝐮𝐭 𝐍𝐢𝐚𝐜𝐢𝐧𝐚𝐦𝐢𝐝𝐞 𝐚𝐧𝐝 𝐒𝐤𝐢𝐧 𝐏𝐫𝐨𝐭𝐞𝐜𝐭𝐢𝐨𝐧

Niacinamide is currently one of the most celebrated ingredients in skincare, praised in every beauty and wellness journal for its ability to strengthen the skin barrier topically. But lately, there has been a lot of buzz about taking it orally to prevent skin cancer.

Does the science back up the hype? Yes—but with some major caveats. Let’s break down the facts and bust a few common myths based on recent clinical literature.

❌ Myth 1: Taking Vitamin B3 means you can skip the sunscreen. Fact: Oral nicotinamide does absolutely nothing to prevent sunburn. It works under the surface by preventing UV-induced immune suppression and supporting your cells’ natural DNA repair mechanisms. Think of sunscreen as your shield, and nicotinamide as your internal clean-up crew.

❌ Myth 2: Any Vitamin B3 supplement from the grocery store will work. Fact: Form matters. You need Nicotinamide (also called Niacinamide). If you accidentally purchase Nicotinic Acid (regular Niacin), you are highly likely to experience “niacin flush”—a harmless but highly uncomfortable reaction that causes your face and neck to turn bright red, itchy, and hot.

❌ Myth 3: The science is completely settled for everyone. Fact: While a landmark clinical trial showed a 23% reduction in skin cancers, and a massive 2025 study of 33,000+ veterans found up to a 54% reduction when started early, recent medical reviews remind us that the evidence isn’t one-size-fits-all. The benefits are overwhelmingly seen in high-risk individuals—specifically those who already have a history of basal cell or squamous cell carcinomas. It has not been shown to prevent melanoma.

The Bottom Line: At around $10 a month, oral nicotinamide (typically studied at 500 mg, twice daily) is an incredibly safe, accessible, and evidence-backed tool for repeat skin cancer prevention. However, the medical community agrees that “the jury is still out” on recommending it to the general population who have never had skin cancer.

If you have a history of significant sun damage, your best move is to skip the social media advice and have a direct conversation with your dermatologist.

#HealthMyths #SkincareScience #PreventativeMedicine #Dermatology #EvidenceBasedHealth #VitaminB3

Real-World Evidence vs. Meta-Analyses: The Evolving Debate on Nicotinamide for Skin Cancer Chemoprevention

Real-World Evidence vs. Meta-Analyses: The Evolving Debate on Nicotinamide for Skin Cancer Chemoprevention

The clinical utility of oral nicotinamide (NAM) for non-melanoma skin cancer (NMSC) chemoprevention remains a prime example of the tension between landmark RCT data, real-world evidence (RWE), and systematic evidence syntheses.

While the 2015 Phase 3 ONTRAC trial established a 23% reduction in new NMSCs among high-risk patients (Damian et al., NEJM), subsequent meta-analyses and recent large-scale observational data have triggered a nuanced methodological debate.

The New Evidence Landscape

  1. The VA Corporate Data Warehouse Cohort (JAMA Dermatol, Nov 2025): Breglio et al. conducted a massive retrospective cohort study of 33,822 US veterans. Utilizing propensity score matching, the authors found an overall 14% reduction in skin cancer risk with oral nicotinamide (500 mg, twice daily for >30 days). Strikingly, when initiated early—after a first skin cancer diagnosis—the risk reduction rose to 54%. However, this benefit declined when treatment was initiated after multiple subsequent malignancies. Among solid organ transplant recipients (SOTRs), no overall significant risk reduction was observed, though early use trended with reduced cutaneous squamous cell carcinoma (cSCC) incidence. (Source: JAMA Dermatol. 2025;161(11):1140-1147. doi:10.1001/jamadermatol.2025.3238)

  2. The Meta-Analytic View (Nutrients): Conversely, a systematic review and meta-analysis by Tosti et al. pooled data across immunocompetent and immunosuppressed cohorts, concluding that current pooled evidence is insufficient to demonstrate a statistically significant reduction in NMSC incidence (BCC RR: 0.88, 95% CI: 0.50-1.55; SCC RR: 0.81, 95% CI: 0.48-1.37). (Source: Nutrients. 2024;16(1):100. doi:10.3390/nu16010101)

  3. Methodological Critique (Am J Clin Dermatol, March 2026): In a critical appraisal titled “Nicotinamide for Skin Cancer Chemoprevention: The Jury Was Out and Still Is,” Tan and Williams challenge the optimism of the 2025 VA study. They highlight significant vulnerability to residual unmeasured confounding, immortal time bias, exposure misclassification, and limited external validity given the demographic skew of the VA population. (Source: Am J Clin Dermatol. 2026;27(2):209-215. doi:10.1007/s40257-025-01005-y)

The HEOR & Clinical Takeaway

From a biological standpoint, NAM’s mechanism is compelling: it prevents UV-induced ATP depletion, replets cellular NAD+ stores, and enhances energy-dependent DNA repair pathways while mitigating UV-induced immunosuppression.

However, from an evidence-generation perspective, this timeline underscores a classic challenge:

  • RCTs demonstrate efficacy under tightly controlled, high-risk conditions.

  • Large-scale RWE suggests strong real-world effectiveness, particularly if introduced as an early intervention.

  • Critical Appraisals & Meta-analyses remind us that retrospective observational data must be interpreted with extreme caution due to structural biases.

While the “jury is still out” on routine, widespread clinical adoption for all patient types, oral NAM remains an inexpensive (~$10/month), highly tolerable option for high-risk individuals. The key moving forward will be refining patient selection—identifying precisely who benefits most, and at what stage of their oncological history.

#Dermatology #Oncology #RealWorldEvidence #SkinCancer #ClinicalResearch #HEOR #Epidemiology

𝗙𝗿𝗼𝗺 𝗢𝗯𝘀𝗲𝗿𝘃𝗮𝘁𝗶𝗼𝗻 𝘁𝗼 𝗖𝗼𝗻𝘁𝗿𝗼𝗹: 𝗧𝗵𝗲 𝗡𝗲𝘄 𝗘𝗿𝗮 𝗼𝗳 𝗖𝗼𝗺𝗽𝘂𝘁𝗮𝘁𝗶𝗼𝗻𝗮𝗹 𝗡𝗲𝘂𝗿𝗼𝘀𝗰𝗶𝗲𝗻𝗰𝗲.

𝗪𝗵𝘆 𝘁𝗵𝗲 𝗙𝘂𝘁𝘂𝗿𝗲 𝗼𝗳 𝗕𝗶𝗼𝘁𝗲𝗰𝗵 𝗗𝗲𝗽𝗲𝗻𝗱𝘀 𝗼𝗻 𝗕𝗿𝗶𝗱𝗴𝗶𝗻𝗴 “𝗪𝗲𝘁𝘄𝗮𝗿𝗲” 𝗮𝗻𝗱 𝗦𝗼𝗳𝘁𝘄𝗮𝗿𝗲.𝗧𝗵𝗲 𝗡𝗲𝘅𝘁 𝗟𝗲𝗮𝗽 𝗶𝗻 𝗔𝗜: 𝗚𝗿𝗼𝘂𝗻𝗱𝗶𝗻𝗴 𝗠𝗮𝗰𝗵𝗶𝗻𝗲 𝗟𝗲𝗮𝗿𝗻𝗶𝗻𝗴 𝗶𝗻 𝗕𝗶𝗼𝗹𝗼𝗴𝗶𝗰𝗮𝗹 𝗣𝗵𝘆𝘀𝗶𝗰𝘀. 𝗙𝗿𝗼𝗺 𝗢𝗯𝘀𝗲𝗿𝘃𝗮𝘁𝗶𝗼𝗻 𝘁𝗼 𝗖𝗼𝗻𝘁𝗿𝗼𝗹: 𝗧𝗵𝗲 𝗡𝗲𝘄 𝗘𝗿𝗮 𝗼𝗳 𝗖𝗼𝗺𝗽𝘂𝘁𝗮𝘁𝗶𝗼𝗻𝗮𝗹 𝗡𝗲𝘂𝗿𝗼𝘀𝗰𝗶𝗲𝗻𝗰𝗲. The future of AI and biotech isn’t just about collecting more data; it’s about building better models of the underlying “physics” of the system. We are seeing a significant shift where classical differential equations are converging with modern machine learning. This hybrid approach is set to redefine how we process neural signals and design cognitive interventions.

Currently, the hierarchy of Ordinary Ddifferential Equations (ODE), Partial DE, and Stochastic DE models allows us to map everything from deterministic whole-brain networks to stochastic membrane fluctuations. This multiscale approach is vital because it ensures that our models remain grounded in biological reality while benefiting from the computational power of ML-driven inference.

One of the most exciting “open challenges” in this field is the move toward control-oriented formulations. Once we can accurately model neural dynamics using these mathematical frameworks, we can begin to design systems that don’t just observe the brain but interact with it in real-time to correct pathological states or enhance performance.

This convergence has massive implications for the “Global Economy” of health and technology. By integrating kinetic variables and mean-field equations with neural field theory, we are creating a standardized language for computational neuroscience that can be scaled across research and industrial applications.

I am particularly focused on how these models will tackle multiscale inference in the coming years. As we refine our numerical and computational approaches for stochastic systems, the gap between “wetware” (the brain) and “software” (AI) will continue to shrink. The math may be complex, but the potential for innovation is limitless.

𝗧𝗵𝗲 𝗠𝗮𝘁𝗵𝗲𝗺𝗮𝘁𝗶𝗰𝗮𝗹 𝗔𝗿𝗰𝗵𝗶𝘁𝗲𝗰𝘁𝘂𝗿𝗲 𝗼𝗳 𝗡𝗲𝘂𝗿𝗼𝗽𝗹𝗮𝘀𝘁𝗶𝗰𝗶𝘁𝘆: 𝗜𝗻𝘁𝗲𝗴𝗿𝗮𝘁𝗶𝗻𝗴 𝗗𝗘 𝗠𝗼𝗱𝗲𝗹𝘀 𝘄𝗶𝘁𝗵 𝗠𝗼𝗱𝗲𝗿𝗻 𝗠𝗟

𝗧𝗵𝗲 𝗠𝗮𝘁𝗵𝗲𝗺𝗮𝘁𝗶𝗰𝗮𝗹 𝗔𝗿𝗰𝗵𝗶𝘁𝗲𝗰𝘁𝘂𝗿𝗲 𝗼𝗳 𝗡𝗲𝘂𝗿𝗼𝗽𝗹𝗮𝘀𝘁𝗶𝗰𝗶𝘁𝘆: 𝗜𝗻𝘁𝗲𝗴𝗿𝗮𝘁𝗶𝗻𝗴 𝗗𝗘 𝗠𝗼𝗱𝗲𝗹𝘀 𝘄𝗶𝘁𝗵 𝗠𝗼𝗱𝗲𝗿𝗻 𝗠𝗟. 𝗕𝗲𝘆𝗼𝗻𝗱 𝘁𝗵𝗲 𝗦𝗶𝗻𝗴𝗹𝗲 𝗡𝗲𝘂𝗿𝗼𝗻: 𝗔 𝗨𝗻𝗶𝗳𝗶𝗲𝗱 𝗛𝗶𝗲𝗿𝗮𝗿𝗰𝗵𝘆 𝗳𝗼𝗿 𝗠𝘂𝗹𝘁𝗶𝘀𝗰𝗮𝗹𝗲 𝗡𝗲𝘂𝗿𝗮𝗹 𝗠𝗼𝗱𝗲𝗹𝗶𝗻𝗴. 𝗕𝗿𝗶𝗱𝗴𝗶𝗻𝗴 𝘁𝗵𝗲 𝗚𝗮𝗽: 𝗙𝗿𝗼𝗺 𝗗𝗲𝘁𝗲𝗿𝗺𝗶𝗻𝗶𝘀𝘁𝗶𝗰 𝗢𝗗𝗘𝘀 𝘁𝗼 𝗦𝘁𝗼𝗰𝗵𝗮𝘀𝘁𝗶𝗰 𝗣𝗼𝗽𝘂𝗹𝗮𝘁𝗶𝗼𝗻 𝗗𝘆𝗻𝗮𝗺𝗶𝗰𝘀.

Large neuronal networks exhibit complex dynamics across multiple scales, from single-neuron excitability to whole-brain rhythms. At the Institute, we are examining how a unified hierarchy of differential equations can bridge these gaps. This framework connects deterministic, stochastic, and mean-field descriptions, providing a robust toolkit for multiscale modeling in computational neuroscience.

Ordinary Differential Equation (ODE) models, such as conductance-based systems, allow us to summarize macroscopic neural behavior through reduced variables. However, to understand population-level activity, we must transition to mean-field Partial Differential Equation (PDE) models. Equations like the Fokker-Planck or age-structured kinetic equations describe how probability densities evolve over synaptic states, linking individual mechanisms to collective oscillations.

Because variability is a hallmark of biological neural systems, our current focus emphasizes Stochastic Differential Equations (SDEs) and their extensions into jump-diffusion processes. These stochastic models are essential for describing random membrane fluctuations and irregular spike trains. They are not merely theoretical; they are critical for quantifying noise in electrophysiological recordings and inferring latent neural dynamics.

The versatility of this ODE-PDE-SDE framework offers a path toward integrated neural signal processing and cognitive modeling. By relating stochastic variability back to surrounding deterministic frameworks, we can better analyze bifurcations and collective patterns that define healthy versus pathological brain states.

We conclude by looking toward the next frontier: the integration of these differential equation models with modern machine learning. Addressing open challenges in multiscale inference and control-oriented formulations is essential for the future of neuroplasticity research and the development of advanced neuro-therapeutics.

𝐃𝐞𝐜𝐨𝐝𝐢𝐧𝐠 𝐔𝐧𝐜𝐞𝐫𝐭𝐚𝐢𝐧𝐭𝐲: 𝐔𝐬𝐢𝐧𝐠 𝐒𝐭𝐨𝐜𝐡𝐚𝐬𝐭𝐢𝐜 𝐄𝐪𝐮𝐚𝐭𝐢𝐨𝐧𝐬 𝐭𝐨 𝐔𝐧𝐝𝐞𝐫𝐬𝐭𝐚𝐧𝐝 𝐭𝐡𝐞 𝐁𝐫𝐚𝐢𝐧’𝐬 𝐂𝐡𝐚𝐨𝐬

𝐎𝐫𝐝𝐞𝐫 𝐟𝐫𝐨𝐦 𝐂𝐡𝐚𝐨𝐬: 𝐇𝐨𝐰 𝐑𝐚𝐧𝐝𝐨𝐦𝐧𝐞𝐬𝐬 𝐃𝐫𝐢𝐯𝐞𝐬 𝐍𝐞𝐮𝐫𝐚𝐥 𝐋𝐞𝐚𝐫𝐧𝐢𝐧𝐠 𝐚𝐧𝐝 𝐏𝐥𝐚𝐬𝐭𝐢𝐜𝐢𝐭𝐲. 𝐖𝐡𝐲 “𝐍𝐨𝐢𝐬𝐞” 𝐢𝐬 𝐭𝐡𝐞 𝐒𝐞𝐜𝐫𝐞𝐭 𝐒𝐚𝐮𝐜𝐞 𝐨𝐟 𝐇𝐮𝐦𝐚𝐧 𝐈𝐧𝐭𝐞𝐥𝐥𝐢𝐠𝐞𝐧𝐜𝐞. 𝐃𝐞𝐜𝐨𝐝𝐢𝐧𝐠 𝐔𝐧𝐜𝐞𝐫𝐭𝐚𝐢𝐧𝐭𝐲: 𝐔𝐬𝐢𝐧𝐠 𝐒𝐭𝐨𝐜𝐡𝐚𝐬𝐭𝐢𝐜 𝐄𝐪𝐮𝐚𝐭𝐢𝐨𝐧𝐬 𝐭𝐨 𝐔𝐧𝐝𝐞𝐫𝐬𝐭𝐚𝐧𝐝 𝐭𝐡𝐞 𝐁𝐫𝐚𝐢𝐧’𝐬 𝐂𝐡𝐚𝐨𝐬.

In most engineering disciplines, “noise” is an enemy to be filtered out or minimized. However, in the human brain, noise is a fundamental feature of the architecture. My recent work explores how stochastic neural dynamics—the inherent randomness in how our neurons fire—actually enables the complexity and adaptability we call intelligence.

When we model the brain, we often start with deterministic equations (ODEs) to map out the basic structure. But to capture the “vibe” of real biological systems, we have to embrace Stochastic Differential Equations (SDEs). These models help us understand the irregular spike trains and synaptic plasticity that allow the brain to learn and reorganize itself.

By focusing on the evolution of population densities through Fokker-Planck equations, we can see how individual “random” actions at the cellular level emerge as organized patterns at the mesoscopic level. It is a fascinating look at how order arises from apparent chaos, providing a mathematical lens for the study of neurovariability.

For those of us working at the intersection of data science and biology, this approach is a game-changer for neural data analysis. It allows us to move beyond simple signal averaging and instead infer the “latent dynamics”—the hidden rules governing brain activity—even when the recordings are incredibly noisy.

The goal is to move toward a unified toolset for multiscale modeling. Whether we are looking at single-cell excitability or whole-brain activity, the hierarchy of ODE, PDE, and SDE models provides the bridge. Embracing the math of uncertainty is ultimately what will lead us to a deeper understanding of human cognition.

Accelerating the Orphan GPCR Pipeline: GPR149 as a Case Study in Dual-Domain Target Validation

https://doi.org/10.1016/j.drudis.2026.104678  Free download of the article using this link until June 16:  https://authors.elsevier.com/a/1n0uP4r9Rkz1l6

Highlights

  • New four-pillar framework accelerates deorphanization of dark GPCR targets. (77 chars)
  • GPR149 structural analysis identifies non-canonical ERY and DPxxF motifs. (76 chars)
  • Path-agnostic screening bypasses traditional Gi/o signaling limitations. (75 chars)
  • Integrated CNS and metabolic mapping reveals GPR149′s dual-domain value. (76 chars)
  • Blueprint provides high-resolution de-risking for first-in-class assets. (74 chars)
High failure rates in drug development for central nervous system (CNS) and metabolic diseases frequently stem from a lack of knowledge about their selected drug targets. With unknown ligand chemistry, orphan G-protein-coupled receptors (GPCRs) represent high-risk, but high-potential, high-reward opportunities for pharmaceutical development. Here, I describe a framework for de-risking such targets using GPR149 as a prototype. The Four-Pillar Framework, combining high-throughput screening, cryo-electron microscopy (EM), artificial intelligence (AI)-driven chemistry, and parallel circuit validation, unexpectedly revealed the dual metabolic (weight loss) and CNS applications of GPR149. In the process, a seemingly intractable orphan receptor has become a development asset with blockbuster potential. This methodology offers a reproducible template for exploring the ‘dark GPCRome’, particularly for disorders in which metabolic dysfunction and CNS comorbidities co-present in real-world patient populations.

    Keywords:

    orphan GPCR, GPR149, deorphanization, target validation, dual-domain therapeutics, drug discovery pipeline, cryo-EM, AI-driven chemistry, circuit-level pharmacology, incremental risk mitigation

    Introduction: prioritizing and de-risking the dark GPCRome

    The ‘dark GPCRome’ represents one of the most significant untapped frontiers in modern drug discovery. Although GPCRs remain the most successful class of drug targets, accounting for ∼35% of all US Food and Drug Administration (FDA)-approved therapeutics and nearly 60% of current prescriptions, most of this success is concentrated within a well-trodden subset of this superfamily.(p1),(p2) Most approved agents target the Class A (rhodopsin-like) subfamily, characterized by the seven-transmembrane helix architecture and highly conserved signaling motifs, such as DRY, CWxP, and NPxxY.(p3) However, a modern drug discovery lens necessitates moving beyond these established targets to de-risk ‘dark’ receptors that deviate from these canonical sequences, where structural and functional gaps have historically stalled development.
    GPR149 epitomizes this non-canonical challenge. Although phylogenetically classified within the rhodopsin-like subfamily, GPR149 lacks the crucial charged residues of the hallmark Asp-Arg-Tyr (DRY) motif, featuring instead a divergent ERY triplet.(p4) This specific substitution at the 3.50 position (Ballesteros–Weinstein numbering) is not merely a sequence variation; it likely dictates high constitutive activity and unconventional G-protein coupling of the receptor.
    Despite being cloned nearly a quarter-century ago (initially as PGR10), GPR149 remains a classic orphan, trapped in the ‘valley of death’ between academic phenotypic discovery and commercial R&D advancement.(p5)

    The productivity paradox: Eroom’s Law

    This stagnation is not merely a function of difficult biology. It reflects a well-documented phenomenon known as ‘Eroom’s Law’ (‘Moore’s Law’ spelled backward). First articulated during the early 2010s, Eroom’s Law describes the observation that the number of new drugs approved per billion dollars spent on pharmaceutical R&D has halved approximately every 9 years since 1950. This trend persists despite, or perhaps because of, technological advances in screening, computing, and molecular biology. The drivers include what has been termed the ‘better than the Beatles’ problem (new drugs must compete against an ever-improving catalog of effective generics), increasing regulatory caution, diminishing returns from brute-force screening approaches, and the tendency to simply allocate more resources to failing strategies rather than rethinking the underlying logic of discovery.(p1),(p2),(p3)
    Orphan GPCRs sit at the epicenter of this challenge. They offer high-reward opportunities not simply because they are unexplored, but because their anatomical expression patterns, strategically enriched in hypothalamic feeding circuits, mesolimbic reward pathways, and glial populations governing myelination, position them as master regulators of physiology with direct therapeutic relevance. GPR149 exemplifies this logic: its localization to the arcuate hypothalamus and nucleus accumbens, coupled with validated roles in energy homeostasis and oligodendrocyte progenitor cell (OPC) differentiation, transforms an orphan receptor from a biological mystery into a strategic asset. Yet, this promise carries correspondingly high risk because of non-canonical signaling motifs, unknown ligand chemistry, and uncertain clinical translatability. Therefore, a paradigm shift is required: one that treats deorphanization not as a sequential hunt for a ligand but as an integrated, parallelized de-risking campaign.

    A paradigm shift in target validation

    Historically, deorphanization has been a step-by-step process hampered by long timelines and high failure rates. Final deorphanization occurred, in part, due to luck. Today, a paradigm shift is possible through the combination of disruptive technologies: multiplexed functional assays, AI-driven de novo design, and cryo-electron microscopy (cryo-EM). By enabling near-atomic-resolution imaging of fragile GPCR complexes in their native states without the need for crystallization, cryo-EM, coupled with generative AI, allows researchers to visualize dynamic biological mechanisms in action. Together, these tools offer the potential to methodically de-risk the entire biology of a target simultaneously, rather than simply hunting for a ligand.

    The Future of PTSD Treatment: Beyond the Daily Pill

    We are currently witnessing a “Neuroplasticity Revolution” that is redefining the landscape of mental health care. Traditional treatments have often focused on managing the symptoms of PTSD through daily medication, but the focus is now shifting toward remodeling the brain’s actual architecture. This approach aims to fix the “hardware” of the brain, rather than just adjusting the “software” of our daily moods.

    A recent 2025 scientific review highlights that treating PTSD effectively requires a deep understanding of how trauma disrupts the brain’s internal communication. In the past, we treated the brain as a collection of separate parts; today, we see it as an interconnected web of circuits. When one part of the circuit—like the hippocampus, which manages memory—is damaged by stress, it affects the entire system’s ability to function.

    What makes this new era of innovation so exciting is the move toward Precision Medicine. We are beginning to understand that our genetic makeup, such as variations in the BDNF gene, influences how we respond to both stress and treatment. This knowledge allows clinicians to move away from a “one-size-fits-all” approach and toward personalized strategies that respect each individual’s unique biological blueprint.

    We are also seeing the emergence of “Interventional Psychiatry.” Tools like Transcranial Magnetic Stimulation (TMS) and the studied use of substances that promote rapid neural growth are being explored to “prime” the brain for change. These aren’t just new drugs; they are “plasticity enhancers” designed to open a temporary window where therapy can be significantly more effective than it would be on its own.

    The synergy between technology and therapy is the key to this breakthrough. By using advanced imaging to track how brain tracts are responding to treatment, doctors can adjust their approach in real-time. This level of insight was unimaginable a decade ago, but it is quickly becoming the gold standard for treating complex conditions like PTSD and treatment-resistant depression.

    As we move through 2026, the goal is to make these high-tech, biology-driven treatments accessible to everyone who needs them. By bridging the gap between laboratory science and real-world clinical practice, we can offer survivors a path to recovery that is faster, deeper, and more lasting. The future of mental health is not just about coping—it’s about the active, scientific restoration of the human spirit.

    #Innovation #HealthTech #PTSD #Psychiatry #FutureOfMedicine #Neuroplasticity #BrainScience