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Showing posts with label Nicardipine. Show all posts
Showing posts with label Nicardipine. Show all posts

Tuesday, 5 August 2025

Keeping ahead of the curve in Autism (and Pitt Hopkins syndrome) treatment - the placebo effect, clinical trials, and a promising case study

Since AI is a trending tool in this blog, I decided to let ChatGPT rewrite today's post. It did rather strip out the science bits.  It added the "don't wait for permission at the end"—a little cheeky, I think. It does like to use dashes.

 

Keeping out in front of the pack is not always easy


Today’s post highlights a compelling new case study—one that turns theoretical research into a real therapy.


About time too! That was my reaction when a reader sent me the paper.

This case study reports on the repurposing of a cheap, well-known drug—Nicardipine—to treat Pitt Hopkins syndrome (PTHS). The drug had already shown promise in earlier mouse models.

So why aren’t we doing this more often? Because the system misunderstands risk.


What About the Risk?

When it comes to trying new treatments, people often fixate on the risk of the therapy itself. But that’s only half the equation. The risk of doing nothing is often much greater—especially in autism.

Most conventional drug repurposing therapies pose minimal long-term risk. Things change only when you start injecting compounds or using untested chemicals. But even then, there’s surprisingly little harm on record.

Only one death has ever been clearly attributed to a therapy for autism:

A 5-year-old autistic boy from the UK died in the US while undergoing chelation therapy. The wrong form of EDTA—disodium EDTA instead of calcium EDTA—was used. The result was fatal hypocalcemia-induced cardiac arrest. The doctor administering the therapy didn’t understand the pharmacology.

Lesson: Always read the label.

Meanwhile, the risk of death from untreated autism is well established:

  • In severe autism, common causes include drowning, accidents, and seizures.
  • In milder cases, the biggest risk is suicide.

Another overlooked danger, mentioned previously in this blog, is polydipsia—excessive water drinking—which can cause hyponatremia (low blood sodium), leading to seizures, coma, and even death.

Bottom line?


The risks from untreated autism far exceed the risks from science-based, carefully applied therapies.


The Nicardipine Case Study

A newly published study builds on promising mouse results and shows real benefit in a young child with PTHS. The drug used—Nicardipine—has been around since 1988 and is commonly prescribed to older adults for high blood pressure or angina.

🔗 Read the case study

Highlights:

  • Pitt Hopkins syndrome involves loss of function in the TCF4 gene, leading to overactivity of Nav1.8 sodium channels in neurons.
  • Nicardipine inhibits Nav1.8, making it a logical therapy.
  • In this case study, the child received oral nicardipine for 7 months (0.2–1.7 mg/kg/day).
  • Result: Mild to moderate improvement in all developmental areas, and reduced restlessness.
  • No significant side effects reported.

It’s not a magic bullet—but it’s a start.
Used as part of polytherapy, this could become a powerful tool for treating PTHS.

And there’s more coming: Vorinostat, another potential therapy, is entering human trials.


Why Don’t More Therapies Get Adopted?

A recent paper by Antonio Hardan sheds light on this. He’s the researcher who showed that the OTC antioxidant NAC benefits many with autism, and later explored the hormone vasopressin.

This time, he tackled the placebo effect—a real barrier in autism research.

🔗 Placebo Effect in Clinical Trials in Autism: Experience from a Pregnenolone Treatment Study

What They Did:

  • A two-week placebo lead-in before the main trial.
  • The drug tested was pregnenolone, a neurosteroid.
  • They used parent-reported ABC-I scores to measure irritability.

What They Found:

  • A 30% reduction in irritability—just from placebo.
  • Also improvements in lethargy, hyperactivity, and repetitive speech.
  • The placebo effect was strongest in the first two weeks, then plateaued.
  • Clinician-rated scores (CGI) did not show this placebo response.

The Takeaway:

Parent expectations strongly shape trial results—at least in the early stages.
A placebo lead-in is a clever way to measure and filter out this noise.


Early Adopters, Take Note

It pays to be ahead of the curve.

Some Pitt Hopkins parents are already trying nicardipine at home based on this case study. Good luck to them—I hope they find the right specialists and support.

Let’s not forget: the big autism trials of recent years—Bumetanide, Memantine, Balovaptan, Oxytocin, Arbaclofen—all officially “failed.”

But the drugs didn’t fail—the trial designs did.

Each of these drugs helped some individuals. The problem?
The trials weren’t structured to identify responder subgroups. We wasted time, money, and hope by not tailoring inclusion criteria more carefully.

Consider Trofinetide, the first FDA-approved drug for Rett syndrome (2023). It helps only 20% of patients, but was still approved.

I’d argue that Bumetanide has an even higher response rate in severe autism, particularly with intellectual disability—and that the best outcome measure is IQ, not a generalized autism scale.


My Own Example: No Placebo Here

How do I know I wasn’t misled by the parental placebo effect?

Simple. No one knew I was trialing treatments—not even the teachers or therapists. That meant their feedback was objective and uninfluenced by my hopes.

My son Monty went from being unable to do basic subtraction at age 9, to later passing his externally graded IGCSE high school math exam.

Not bad for a therapy that mainstream medicine still ignores.


Final Thoughts

  • Drug repurposing is safe, smart, and often effective.
  • The placebo effect is real—but it’s measurable and manageable.
  • If we want progress in autism treatment, we need smarter trial designs, not just more of them.
  • Being ahead of the curve isn’t risky—it’s essential.

💡 Stay informed, stay curious, and don’t wait for permission.


Thanks for the guest post, ChatGPT !!


One point to add to the risk assessment: by my estimation, each year in the US, around 200 to 300 people die from drowning, seizures, accidents, and suicides related to autism. In living memory, only one person has died as a result of visiting an autism doctor in the US and that death was entirely preventable.

Vorinostat, a potent HDAC inhibitor trialed in several autism models, was mentioned in the above post. Interestingly, there is a recent comment from a reader who finds it resolves 80% of his autism but only for about 2 hours. The half-life of this drug is about 2 hours. There are discussions on Reddit by people using it for autism, anxiety, PTSD etc. It is about 1,000 times more potent than HDAC inhibitors people typically might try at home. Perhaps there should be trials of micro-dosing Vorinostat? I think daily use of high-dose Vorinostat may not work well, due to side effects.  Human trials will soon inform us better. It is often older people who struggle with drug side effects, not children.  

Vorinostat may not only correct Differentially Expressed Genes (DEGs) but also:

  • Increase synaptic plasticity
  • Improve synaptic morphology (the shape and function of neuronal connections)
  • Improve memory and cognition 

The main research interest is in single gene autisms, where one specific gene is under-expressed (eg Pitt Hopkins, Rett, Fragile-X etc) but the general ideas are equally applicable to broader autism. 




Thursday, 6 October 2022

Different L-type Calcium Channel Blockers Repurposed for Different Types of Autism

 

 A Purkinje Neuron, home of P-type calcium channels

Today’s post was prompted by a reader who saw a very positive response from the L-type calcium channel blocker, Amlodipine.

So we return to the subject of calcium channels.

The good news about calcium channel defects is that many are easy to treat.

In most single gene autisms (Rett, Fragile-X, Pitt Hopkins etc) the underlying problem is that a faulty gene does not do its job of producing the expected protein.  This is a problem of too little.

In many ion channel dysfunctions the problem is not too little, it is too much expression. For example, in Timothy Syndrome the mutation in the gene produces too much of the protein, in this case the L-type calcium channel Cav1.2.

Ion channel dysfunctions can be the result of a faulty gene, or just that the on/off switch for that gene is faulty.  Fortunately, the problem is usually that it is stuck “on”.

In people who develop Type-1 diabetes we have seen how the disease process can be halted by blocking Cav1.2 in the pancreas.  This halts the decline in the beta cells that produce insulin.

Once all the beta cells are dead, the person cannot produce insulin and has type-1 diabetes. Treating the person after this point with a Cav1.2 blocker will provide no benefit; the damage has already been done

Something similar happens in Parkinson’s disease, but this time you need to block Cav1.3.  In the early stages of the disease Cav1.3 is over-expressed in a key part of the brain, which triggers a slow process of degeneration. Treating a person with all the visible symptoms of Parkinson’s with a Cav1.3 blocker will provide no benefit; the damage has already been done.

 

Calcium channel blockers are not very specific

The current drugs used to block calcium channels were mainly developed to treat heart conditions.

When treating neurological disorders like autism we are primarily focused on the brain, what goes on elsewhere can also be very relevant, but in an indirect way.

In the brain the important calcium channels are: -

L type

N type

P type

R type

T type

Plus, Inositol trisphosphate receptor (IP3R) and Ryanodine receptors. IP3R has been covered in previous posts.


Verapamil (a Phenylalkylamine class drug)

Verapamil blocks L type channels and T type channels, plus some potassium ion channels.

When it comes to specific L type channels there are 4, Cav1.1, Cav1.2, Cav1.3, and Cav1.4.

In the brain we have just Cav1.2 and Cav1.3. Verapamil mainly affects Cav1.2.

 

Amlodipine (a Dihydropyridine class drug)

Amlodipine blocks L type channels and N type channels.

Amlodipine mainly affects Cav1.3.

 

Nicardipine (a Dihydropyridine class drug)

Nicardipine blocks L type channels and N type channels.

As a Dihydropyridine, it should mainly affect Cav1.3.

In addition, it blocks the sodium ion channel Nav1.8.

The effect on Nav1.8 is why it has been proposed as a therapy for Pitt Hopkins. In this syndrome Nav1.8 is over expressed as a downstream consequence of a mutation in the TCF4 gene.

 

Effect on P channels

To some extent Verapamil, Amlodipine and Nicardipine all block P channels.

P channels are called P after the Purkinje neurons, where they are located. These Purkinje cells likely define some aspects of autism, because of their absence. Purkinje neurons are among the largest in the brain, with elaborate dendritic arbor.  I imagine this makes them vulnerable.




In the people with severe autism most of the Purkinje cells appear to have died.

Blocking P channels might have protected Purkinje cells from death.

 

The effect of too much L-type calcium channel signaling on behavior 

You can both turn on self-injury via activating L type calcium channels and extinguish it by blocking the same channels.  It is proven in mice and seems to apply to at least some humans.

Calcium channel activation and self-biting in mice

The L type calcium channel agonist (±)Bay K 8644 has been reported to cause characteristic motor abnormalities in adult mice. The current study shows that administration of this drug can also cause the unusual phenomenon of self-injurious biting, particularly when given to young mice.

The self-biting provoked by (±)Bay K 8644 can be inhibited by pretreating the mice with dihydropyridine L type calcium channel antagonists such as nifedipine, nimodipine, or nitrendipine. However, self-biting is not inhibited by nondihydropyridine antagonists including diltiazem, flunarizine, or verapamil.

(±)Bay K 8644 functions as an L type calcium channel activator that increases calcium fluxes in response to depolarizing stimuli (). In rodents, this drug has been reported to produce characteristic motor abnormalities including impaired ambulation, twisting and stretching movements, transient limb extension, back arching, spasticity, ataxia, or catatonia (). Some studies have anecdotally noted the occurrence of SIB with this drug (), though this phenomenon has received little attention. The current study shows that (±)Bay K 8644 will reliably provoke SB and SIB under certain conditions in mice, providing a tool to study the neurobiology of this unusual behavior.

 

When I first encountered the above study, I did wonder why Verapamil did not extinguish the self-injury.

It turns out that Bay K 8644 is a modified version of the common drug nifedipine, which is a Cav1.3 blocker.  Verapamil is mainly a Cav1.2 blocker.  Bay K 8644 is like the opposite of nifedipine.

In the trial they have activated Cav1.3 causing excess calcium inside neurons. The only way to block this process is to block Cav1.3. Blocking Cav1.2 with Verapamil could not solve the problem. 

Note that activation of Cav1.3 can cause motor abnormities in mice and this might be seen as ataxia in a human. One particular reader of this blog will see the relevance of this. 

I did write extensively in earlier posts about the large amount of research that links L type calcium channels to neuropsychiatric disorders.

I did mainly focus on Cav1.2 using Verapamil, but the evidence for the role of Cav1.3 is clear as day. 

L-type calcium channels as drug targets in CNS disorders

 L-type calcium channels are present in most electrically excitable cells and are needed for proper brain, muscle, endocrine and sensory function. There is accumulating evidence for their involvement in brain diseases such as Parkinson disease, febrile seizures and neuropsychiatric disorders. Pharmacological inhibition of brain L-type channel isoforms, Cav1.2 and Cav1.3, may therefore be of therapeutic value.

 

From Gene to Behavior: L-Type Calcium Channel Mechanisms Underlying Neuropsychiatric Symptoms.

The L-type calcium channels (LTCCs) Cav1.2 and Cav1.3, encoded by the CACNA1C and CACNA1D genes, respectively, are important regulators of calcium influx into cells and are critical for normal brain development and plasticity. In humans, CACNA1C has emerged as one of the most widely reproduced and prominent candidate risk genes for a range of neuropsychiatric disorders, including bipolar disorder (BD), schizophrenia (SCZ), major depressive disorder, autism spectrum disorder, and attention deficit hyperactivity disorder.

Here, we provide a review of clinical studies that have evaluated LTCC blockers for BD, SCZ, and drug dependence-associated symptoms, as well as rodent studies that have identified Cav1.2- and Cav1.3-specific molecular and cellular cascades that underlie mood (anxiety, depression), social behavior, cognition, and addiction.

 

Was I surprised that Amlodipine, that targets Cav1.3 rather than Cav1.2, was very beneficial in someone with severe autism?  Not at all.

I was interested that the effect was more pro-cognitive than anti-anxiety.  Is that the effect on Cav1.3 or is it via that N channel Cav2.2?

N-type calcium channels are important in neurotransmitter release because they are localized at the synaptic terminals. Piracetam, the original cognitive enhancing drug, is also a N type channel blocker.

  

Statins and L type calcium channels blockers – it matters which one you choose

We previously saw how the statin class of drugs can be beneficial in autism, but it depends which one you chose. For example, in SLOS (Smith-Lemli-Opitz syndrome), where both copies of the gene DHCR7 are mutated, you need to push the gene to work. To increase expression of this gene you need Simvastatin. This is hard for people to understand because SLOS features very low cholesterol and statins are thought of as cholesterol lowering drugs. The body needs the enzyme DHCR7 to make cholesterol and Simvastatin increases DHCR7 expression.

In the case of L type channel blockers, the selection is very important.  The effect will not be the same.

If you have a mutation in Cav1.2, you would expect Verapamil to be a good choice.  If the mutation is in Cav1.3, you would expect Amlodipine to be better.

If you have over expression of T channels (Cav3.1, Cav3.2 or Cav3.3) then you would expect a benefit from Verapamil and none from Amlodipine.

If you have over expression of the N channel (Cav2.2) then you would want Amlodipine

If you have over expression of the sodium channel Nav1.8 then you would want Nicardipine

  

Conclusion

It is likely that many people with autism, bipolar, ADHD or schizophrenia might benefit from treating their ion channel dysfunctions.  The required drugs are cheap generics that have been in your local pharmacy for a few decades.

Back in 2019 I wrote the post below:

Cheap common drugs may help mental illness

I highlighted a new study, using historic data from Sweden, that looked at the secondary effects of statins, calcium channel blockers and metformin on psychiatric hospitalization.

 

Association of Hydroxylmethyl Glutaryl Coenzyme A Reductase Inhibitors, L-Type Calcium Channel Antagonists, and Biguanides With Rates of Psychiatric Hospitalization and Self-Harm in Individuals With Serious Mental Illness

 

Question  Are drugs in common use for physical health problems (hydroxylmethyl glutaryl coenzyme A reductase inhibitors, L-type calcium channel antagonists, and biguanides) associated with reduced rates of psychiatric hospitalization and self-harm in individuals with serious mental illness?

Findings  In this series of within-individual cohort studies of 142 691 patients with bipolar disorder, schizophrenia, or nonaffective psychosis, exposure to any of the study drugs was associated with reduced rates of psychiatric hospitalization compared with unexposed periods. Self-harm was reduced in patients with bipolar disorder and schizophrenia during exposure to all study drugs and in patients with nonaffective psychosis taking L-type calcium channel antagonists. 

We found that periods of HMG-CoA RI (statin) exposure were associated with reduced psychiatric hospitalization in all subgroups of SMI (Serious Mental Illness) and with reduced self-harm in BPD and schizophrenia.

Exposure to LTCC (L type calcium channel) antagonists was associated with reduced rates of psychiatric hospitalization and self-harm.

Periods of metformin (a type 2 diabetes drug) exposure were associated with reduced psychiatric and nonpsychiatric hospitalization across all SMI subgroups.

 

Use of L type calcium channel blockers reduces self-harm.

How much more evidence is needed?

I took an educated guess several years ago that Verapamil would tame summertime raging in my son.  It was the only calcium channel blocker I tried and it worked. This year we had the emergence of extreme sound sensitivity. My educated guess was that blocking potassium channels with Ponstan (Mefenamic acid) would resolve the problem, and it did.  

Treating ion channel dysfunctions (channelopathies) in autism clearly is not rocket science; it is just waiting to be attempted.