• Rett syndrome is rare but relentless
• Neuren struck biotech gold with Daybue
• Neurotech brings cannabis to the fight

 

Rett syndrome is the kind of diagnosis that hits hard and lingers long.

It affects around one in 10,000 girls, and typically appears after what seems like a normal start to life.

Then comes the regression – loss of speech, hand skills, mobility – followed by the onset of seizures, bone fragility, gut issues, scoliosis and, often, a haunting silence that replaces early babble.

It’s caused by mutations in the MECP2 gene, which plays a crucial role in brain development.

While it’s classed as rare, the ripple effects through families are enormous.

Sleep disturbances are common. Breathing irregularities, like breath-holding spells, can leave caregivers powerless.

And while most girls survive into adulthood, it’s with round-the-clock support and complex medical needs.

 

AussieRett and InterRett studies

Professor Helen Leonard, principal research fellow at the Kids Research Institute, has spent decades studying the condition.

Leonard’s long-running AussieRett and InterRett studies have helped establish how Rett symptoms evolve over time, and her team has also created global care guidelines for things like nutrition, scoliosis and bone health.

“Rett syndrome is an unusual condition in that it mainly affects girls who, following a period of apparent normal development, gradually show signs of regression,” she told Stockhead.

“Between the ages of 6 and 18 months they lose skills, particularly in relation to hand function and communication.

“As well as loss of hand function, these individuals develop unusual patterns of hand movements, such as hand-wringing or clapping known as stereotypies.”

 

Neuren’s moonshot moment

Until recently, there was no approved treatment for Rett, only a patchwork of management strategies and hope.

That changed when ASX-listed Neuren Pharmaceuticals (ASX:NEU) struck gold with its drug trofinetide, now marketed as DAYBUE in the US.

Approved by the FDA in March 2023, DAYBUE became the first and only drug for Rett syndrome, unlocking a commercial windfall for Neuren.

Since 2019, Neuren’s stock has surged over 1,200%, and the company now commands a $2 billion market cap.

Thanks to a savvy licensing deal with Acadia Pharmaceuticals, Neuren pockets royalties and milestone payments with no royalty outgoings – every dollar drops to the bottom line.

“The FDA approval of trofinetide for Rett syndrome is very exciting, and represents the first ever treatment for the disorder,” said Leonard.

For investors, it was a reminder that rare paediatric disorders, long overlooked, are now a serious biotech frontier.

And that’s where Neurotech (ASX:NTI) enters the frame, with a somewhat different approach.

 

Cannabis steps into the ring

Neurotech’s lead therapy, NTI164, is a full-spectrum cannabis extract containing a cocktail of cannabinoids like CBDA, CBC and CBN.

But it only contains 0.08% THC, meaning it’s non-intoxicating and suitable for children.

The company recently published results from its Phase I/II study in the Journal of Paediatrics and Child Health.

This report shows the therapy was well tolerated and offered signs of clinical improvement across neurological, behavioural and functional domains.

The drug’s unique formulation is designed to reduce neuroinflammation, support synaptic function and modulate glial cells – factors believed to play a key role in Rett’s progression.

NTI164 is gaining traction internationally.

It’s already secured Orphan Drug Designation (ODD) in the US and European Union.

This unlocks a range of incentives, including market exclusivity, reduced regulatory fees and access to research funding.

It’s the kind of support that can help fast-track rare-disease drugs through the system.

Meanwhile, data from the same study was presented by lead investigator Professor Carolyn Ellaway at the World Rett Syndrome Congress.

That put NTI164 front and centre in a growing global conversation about next-gen Rett treatments.

 

Caution, hope and next steps

Research into cannabis for Rett is still early, and Leonard urges caution when interpreting results from small, open-label trials.

“I think that we need a larger national double-blind placebo-controlled study before making any judgement,” she said.

“I would hope that this would use an alternative outcome measure to the RSBQ.”

Her research has shown that Rett’s behavioural symptoms – like those measured by the RSBQ – tend to decrease with age; unlike its clinical severity, which often worsens.

That disconnect, she believes, can muddy trial results, and partially explains why she urges a broader toolkit for measuring impact in future studies.

Still, she acknowledged that apart from the Rett Syndrome Symptom Severity (RTT-SIS) scale, some of the other measures used in the NTI164 study “were showing positive changes”.

She’s not easily swayed by early signals but she recognises momentum when it’s building.

And regulators seem to agree.

 

A closer look under NTI’s hood

From a clinical standpoint, NTI164 is ticking key boxes.

Its pharmacokinetic (PK) data shows rapid absorption, minimal THC exposure and consistent dosing with no cannabinoid build-up – making it suitable for chronic paediatric use.

NTI164 has also shown promising results in other paediatric neurological conditions like autism and PANDAS/PANS, potentially supporting its use in Rett by building a broader safety and efficacy profile.

Perhaps most notably, its primary cannabinoid, CBDA, doesn’t just convert into CBD like many assume.

It appears to act directly on the brain, interacting with receptors linked to mood and inflammation.

That matters because Rett isn’t just neurological, it’s deeply inflammatory.

“The clear validation of systemic stability, safety and targeted therapeutic action highlights NTI164’s potential as a disease-modifying therapy,” said Neurotech CEO, Dr Anthony Filippis.

Whether that turns into a commercial home run is still to be seen, but NTI164 has already demonstrated solid safety and early signs of symptom relief.

In Rett, that bar is high. So are expectations.

And that’s what makes Neurotech’s path an interesting one to watch.

 

 

 

At Stockhead we tell it like it is. While Neurotech is a Stockhead advertiser, it did not sponsor this article.

This story does not constitute financial product advice. You should consider obtaining independent advice before making any financial decision.