Real-world effectiveness of highly purified cannabidiol in epilepsy associated with 15q11.2-q13.1 duplication and deletion syndromes: A multicenter study

“This multicenter retrospective study evaluated the effectiveness and safety of highly purified cannabidiol (CBD) in 22 patients with 15q11.2-q13.1 duplication or deletion syndromes (15q-DDS), including 12 with 15q duplication syndrome (dup15q) and 10 with Angelman syndrome (AS).

Median (interquartile range [IQR]) age at CBD initiation was 14.5 (10-22.5) years, with a median (IQR) follow-up of 21 (14-33) months. All dup15q and two AS patients presented with a Lennox-Gastaut phenotype.

At last observation, mean seizure reduction was 55.7% (95% confidence interval 38.7-72.7), with 63.6% patients achieving ≥50% reduction, 40.9% achieving ≥75% reduction, and 18.2% achieving seizure freedom. Tonic seizures in dup15q and myoclonic seizures in AS showed the most notable reductions. EEG improvement was observed in 7/16 patients, with marked improvement observed in two dup15q patients.

Clinical improvement on the Clinical Global Impression-Improvement scale was reported in 72.7%, alongside nonseizure benefits such as improved sleep, behavior, and attention in a subset of patients. CBD was well tolerated; no patient discontinued CBD due to side effects alone, and retention at last visit was 81.8%.

These findings suggest that CBD may provide clinically meaningful benefit in patients with 15q-DDS, including seizure reduction and improvements in sleep, behavior, and attention in selected cases.

PLAIN LANGUAGE SUMMARY: Epilepsy secondary to 15q11.2-q13.1 duplication or deletion syndromes (15q-DDS) is often severe, making daily life difficult for patients and their families. In this study, treatment with highly purified cannabidiol (CBD) reduced seizures in many patients with 15q-DDS. CBD was generally well tolerated, and caregivers also reported improvements in sleep, behavior, and attention in a number of cases.

Overall, these findings suggest that CBD may be a helpful treatment option for people with 15q-DDS.”

https://pubmed.ncbi.nlm.nih.gov/41992447

“Given the substantial disease burden and drug resistance typical of epilepsy in 15q-DDS, CBD may emerge as a promising therapeutic option in these patients.”

https://onlinelibrary.wiley.com/doi/10.1002/epi4.70241

Real-world effectiveness and tolerability of highly purified cannabidiol in patients with monogenic developmental and epileptic encephalopathies with highly active epilepsy

“Developmental and epileptic encephalopathies (DEEs) represent a group of disorders characterized by developmental slowing or regression together with seizures, that are often drug-resistant.”

“With this background, we investigated the effectiveness and tolerability of highly purified CBD in a cohort of monogenic DEEs, focusing on patients with highly active epilepsy.”

“Taken together, these findings suggest that CBD represents a valid therapeutic option for patients with DEEs and highly active epilepsy, providing meaningful seizure reduction even in the most treatment-refractory cases.”

“Our study shows that highly purified CBD may represent a feasible treatment option for patients with DEEs and highly active epilepsy.”

https://www.epilepsybehavior.com/article/S1525-5050(26)00157-5/fulltext

Elucidating the putative role of cannabigerol: a hypothesis-generating review of neuroinflammatory and neuroprotective mechanisms with implications for drug-resistant epilepsy

“Drug-resistant epilepsy (DRE) affects approximately 30% of individuals with epilepsy and remains a major clinical challenge despite the availability of multiple antiseizure medications (ASMs). Beyond recurrent seizures, accumulating evidence implicates chronic neuroinflammation, blood-brain barrier (BBB) dysfunction, excitotoxic injury, and progressive neurodegeneration as processes associated with epileptogenesis and disease progression.

While cannabidiol (CBD) has demonstrated clinical efficacy in specific DRE syndromes, increasing recognition of these mechanisms has motivated interest in exploratory, mechanism-oriented approaches that extend beyond direct seizure suppression.

Cannabigerol (CBG) is a non-psychoactive phytocannabinoid with a pleiotropic pharmacological profile, interacting with cannabinoid receptors, transient receptor potential (TRP) channels, nuclear receptors such as peroxisome proliferator-activated receptor gamma (PPARγ), and additional neuromodulatory targets.

Preclinical studies indicate that CBG can modulate inflammatory, oxidative, and cell-survival pathways across diverse experimental models of neuroinflammatory and neurodegenerative injury. Importantly, most available evidence derives from non-epilepsy paradigms or in vitro systems, and direct support for antiseizure efficacy or disease modification in epilepsy remains limited.

This review synthesizes current preclinical evidence on the molecular targets and mechanistic actions of CBG, with particular emphasis on neuroimmune modulation and neuronal vulnerability, while critically addressing the limitations and translational gaps of the existing literature. Rather than providing confirmatory evidence, this work is intended as a hypothesis-generating framework to inform future epilepsy-focused studies evaluating whether modulation of neuroinflammatory and neurodegenerative pathways by CBG may hold relevance within disease-modifying research strategies for DRE.”

https://pubmed.ncbi.nlm.nih.gov/41919226

“Recent preclinical research has highlighted CBG as a multi-target phytocannabinoid capable of modulating neuroinflammatory, oxidative, and cell-survival pathways across diverse experimental systems.”

https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2026.1755956/full

Cannabidiol in Epilepsy: Restoring Locomotion and Seizure Control

“Epilepsy remains a global challenge, with about one-third of affected patients being resistant to treatment. Seizures and motor abnormalities characterized by movement difficulties are common in epilepsy, highlighting the need for treatments that can both improve motor outcomes and control seizures.

The therapeutic potential of Cannabidiol (CBD) in this regard necessitates a review that explores its effects and underlying mechanisms of action. This study reviewed studies from major scientific databases on the use of CBD in animal and human models of epilepsy. We also integrated tools of network pharmacology and molecular modeling to investigate how CBD may interact with various biological targets. The cannabinoid broadly demonstrates minimal or no changes in motor outcomes, reinforcing its low toxicity and tolerability.

Evidence suggests that CBD has potential for seizure control by prolonging the time to seizure onset and decreasing seizure severity. The antiepileptic effects of CBD involve the modulation of multiple targets or genes. This multitarget interaction network may underlie its neuroprotective effects by regulating endocannabinoid signaling, neurotransmission, inflammation, and metabolic pathways. Chemical bonding between CBD and key protein residues reinforces evidence supporting its interaction with these targets.

Despite the limited clinical data and algorithmic constraints of network pharmacology, the present findings reveal the potential of CBD to improve epileptic outcomes. The multitarget mechanisms of this phytocannabinoid offer valuable insights that may guide and advance epilepsy research.”

https://pubmed.ncbi.nlm.nih.gov/41833036

https://www.eurekaselect.com/article/153518

Cannabinoid Therapies in Less-Common Disorders: Clinical Evidence and Formulation Strategies

Background/Objectives: Cannabinoids are increasingly recognised for their therapeutic potential beyond well-established indications such as chronic pain, multiple sclerosis, and specific epileptic syndromes. Recent advances have highlighted their possible role in less-common or orphan diseases, opening new avenues for pharmaceutical research and clinical application. 

Methods: This review provides a critical synthesis of the most recent evidence (2020-2025), available in PubMed and Scopus, regarding the use of cannabinoids in conditions including refractory epilepsies beyond Dravet and Lennox-Gastaut syndromes, movement disorders such as dystonia and Tourette syndrome, rare dermatological diseases like epidermolysis bullosa, and emerging data in Crohn’s disease. 

Results: Negative outcomes, such as those reported in Fragile X syndrome trials, are also discussed as instructive examples of methodological and pharmacological challenges. Particular attention is given to the optimisation of pharmaceutical formulations and advanced separation technologies, including oromucosal sprays, transdermal gels, and novel nanocarrier systems, which aim to overcome issues of bioavailability and variability in patient response. Finally, safety concerns, regulatory aspects, and the need for robust clinical trials are addressed. 

Conclusions: Overall, cannabinoids represent a promising yet underexplored therapeutic option in rare and complex disorders, warranting further investigation supported by innovative pharmaceutical approaches.”

https://pubmed.ncbi.nlm.nih.gov/41745121

 “Thus, cannabinoids may play an important role in the development of innovative therapies, particularly in the treatment of less-common diseases that often lack effective therapeutic options.”

https://www.mdpi.com/2079-9721/14/2/83


Highly purified cannabidiol (CBD) in CDKL5 deficiency disorder (CDD): Open-label prospective study

Objective: CDKL5 deficiency disorder (CDD) is an early-onset developmental and epileptic encephalopathy characterized by frequent drug-resistant seizures, cerebral visual impairment, motor dysfunction, and sleep and gastrointestinal disturbances. Preliminary evidence suggests that highly purified cannabidiol (CBD) may reduce seizure frequency, but data on its effects on comorbidities are lacking. This study aimed to evaluate the efficacy and safety of CBD in individuals with CDD.

Methods: We conducted a prospective, open-label, single-center study including patients with CDD aged >1 year. Outcomes included motor seizure frequency, caregiver- and clinician-rated Clinical Global Impression (CGI), and changes in sleep, motor abilities, and EEG at 3, 6, and 12 months. CBD plasma levels were measured with High-Performance Liquid chromatography-Mass Spectrometry (HPLC-MS).

Results: Eight of nine patients (all females; median age 10 years, range 1-24) completed the study, with a retention rate at 12 months of 8/9 (89%). One discontinued at 6 months due to a skin rash. A > 50% seizure reduction was observed in 8/9 patients at 3 months, 6/9 at 6 months, and 1/8 at 12 months. Seven patients showed some degree of vigilance improvements, three in motor performance, and two in sleep and constipation. All caregivers reported at least minimal overall improvement (CGI score 3) at 3 months, and three reported marked improvement (CGI score 2), with a peak at 3 months. Five patients showed adverse events during the trial, but none were considered serious. The median CBD dose at all time-points was 15.6 mg/kg/day (IQR 10.0-18.9) corresponding to a plasma dose of 69.9 ng/mL (IQR 29.8-114.6) and the median concentration/dose ratio was 4.7 (IQR 2.7-6.8).

Significance: The safety and efficacy of highly purified CBD in CDD were consistent with previous reports in the literature, with possible benefits beyond seizure control. Further studies are warranted to assess non-seizure outcomes and compare long-term efficacy across treatment options.

Plain language summary: We studied nine girls with CDKL5 deficiency disorder who had frequent, hard-to-treat seizures. They received cannabidiol for up to 1 year, added to their usual medicines. Most children had fewer seizures in the first months of treatment. Some families also noticed better alertness, eye contact, movement, sleep, or constipation. Side effects were usually mild and manageable. Although seizure frequency often returned to baseline by the end of the study, most families chose to continue cannabidiol. Because this was a small study without a placebo group, these results are preliminary, and larger controlled trials are needed.”

https://pubmed.ncbi.nlm.nih.gov/41677102

“In this exploratory prospective open-label trial, we suggest that CBD may be an effective and relatively safe therapeutic option in patients with CDD, which warrants further investigation through randomized controlled trials. CBD may be associated with effects not only on seizures but also on awareness, sleep, and motor functions.”

https://onlinelibrary.wiley.com/doi/10.1002/epi4.70213

Synergistic Neuroprotection by Cannabis sativa and Tilia × viridis: Attenuation of Hippocampal Neurons Glutamate-Induced Oxidative Stress and LPS-Driven Microglial Inflammation

“Throughout history, Cannabis sativa has been linked to the therapeutic management of epilepsy and Tilia × viridis has a tradition of use as a sedative.

This study aimed to evaluate the protective effect of an ethanolic extract of C. sativa (CSRD), an aqueous extract of T. × viridis (TE), and their combination against oxidative stress induced by glutamate in a murine hippocampal neuronal (HT-22) cell line, as well as their anti-inflammatory activity in male Wistar rats’ microglial cells stimulated with LPS.

A phytochemical analysis was also conducted. Glutamate-induced reactive oxygen species (ROS) were quantified using 2′,7′-dichlorodihydrofluorescein diacetate via fluorescence microscopy. Cell viability was assessed using the MTT assay. Distinct microglial cell phenotypes were identified via immunofluorescence.

Extracts partially reversed glutamate-induced loss of cell viability (52% to 200% for CSRD; 22% to 82% for TE). Their combination produced a greater effect, reversing glutamate-induced toxicity by 133% to 284% and fully restoring cell viability to control levels. Moreover, the combined treatment reduced intracellular ROS levels (52% to 58%).

Notably, the combination also exhibited the most pronounced anti-inflammatory effects, significantly reducing the proportion of reactive phenotype 1 cells, while increasing the population of anti-inflammatory phenotype 2 cells and preserving the trophic phenotype 3 subpopulation.

In conclusion, this study not only validates the ethnobotanical uses of C. sativa and T. × viridis but also reveals a potent synergy when combined. This provides a strong foundation for the development of phytomedicines with translational potential for managing complex pathologies like epilepsy or neuroinflammation associated with neurodegenerative diseases.”

https://pubmed.ncbi.nlm.nih.gov/41628619

https://www.thieme-connect.de/products/ejournals/abstract/10.1055/a-2751-0171

Antiseizure Effects of Cannabidiol in Combination With Cannabigerol in the Maximal Electroshock Seizure Model

“Current antiseizure therapy for epilepsy is only effective in about 70% of the patient population.

Previous studies had shown that the addition of small amounts of tetrahydrocannabinol (THC) made cannabidiol (CBD) much more potent in the maximal electroshock seizure (MES) model.

The current study investigated the effects of combining CBD with the non-psychotoxic cannabinoid cannabigerol (CBG) in the MES model in mice.

Mice were administered (i.p.) CBD or CBG or a combination of both before undergoing the MES procedure. Dose-response and dose-toxicity curves were generated for each compound and combinations.

It was found that CBG has antiseizure properties and that it potentiates the effects of CBD.

By using a 1:1 ratio combination of CBD and CBG, the ED50 for CBD was reduced by over 50% and the TD50 for CBD was reduced by 40%, indicating increased toxicity. This suggests that the interaction between CBD and CBG may be additive in nature. Both drugs showed little toxicity at therapeutic doses.

This is the first study to provide detailed dose-response data for CBG as well as CBG in combination with CBD in a seizure model and suggests that the two drugs could act in a similar manner to suppress seizures.”

https://pubmed.ncbi.nlm.nih.gov/41588555

“The present study determines dose–response and dose–toxicity relationships for the non-psychotoxic cannabinoids CBG and CBD in the MES model and finds that CBG has antiseizure effects on its own and can potentiate the antiseizure effects of CBD, possibly in an additive manner. This suggests that CBG and CBD could use similar mechanisms for their antiseizure effects. This study is the first to present antiseizure effects of CBG as well as provide detailed dose–response and dose–toxicity data of CBG in combination with CBD.”

“Cannabinoids have been examined as potential antiseizure drugs but psychotoxic effects and low potency have been problematic. The present study determines dose–response and dose–toxicity relationships for the non‐psychotoxic cannabinoids CBG and CBD in the MES model and finds that CBG has antiseizure effects on its own and can potentiate the antiseizure effects of CBD, possibly in an additive manner. This suggests that CBG and CBD could use similar mechanisms for their antiseizure effects. This study is the first to present antiseizure effects of CBG as well as provide detailed dose–response and dose–toxicity data of CBG in combination with CBD.”

https://onlinelibrary.wiley.com/doi/10.1111/bcpt.70194

Unveiling Neurological Benefits: A Review of Hemp Leaf, Flower, Seed Oil Extract, and Their Phytochemical Properties in Neurological Disorders

“Neurological disorders such as epilepsy, Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis present significant global health care challenges, with complex pathophysiology and limited therapeutic options that often carry substantial side effects.

Hemp-derived compounds, particularly from Cannabis sativa seeds, leaves, and flowers, have gained attention for their potential neuroprotective properties.

This review aims to synthesize the current evidence surrounding the therapeutic benefits of hemp-derived compounds, focusing on their bioactive phytochemical profiles, mechanisms of action, and therapeutic efficacy in treating neurological disorders.

A comprehensive review of pre-clinical and clinical studies was conducted, analyzing the phytochemical composition of hemp extracts, including cannabinoids (such as cannabidiol, CBD), terpenes, flavonoids, and polyunsaturated fatty acids. We explored their mechanisms of action through interactions with the endocannabinoid system, neurotransmitter receptors, inflammatory pathways, and oxidative stress mechanisms.

The review highlights the therapeutic potential of hemp-derived extracts in mitigating various neurological conditions. Pre-clinical and clinical studies have demonstrated their efficacy in reducing seizure frequency in epilepsy, protecting dopaminergic neurons in Parkinson’s disease, alleviating neuroinflammation and oxidative stress in Alzheimer’s disease, and promoting remyelination in multiple sclerosis.

The entourage effect, where cannabinoids, terpenes, and flavonoids work synergistically, enhances these therapeutic effects. Innovations in extraction technologies have optimized yield and preserved bioactivity, further enhancing clinical relevance.

Hemp-derived compounds exhibit significant neuroprotective and therapeutic potential for managing neurological disorders. However, challenges such as product standardization, safety profiles, and regulatory frameworks must be addressed for clinical translation. Further research is essential to optimize dosing, establish safety parameters, and develop standardized formulations, which will be crucial for fully harnessing the therapeutic potential of hemp-derived products in treating neurological conditions.”

https://pubmed.ncbi.nlm.nih.gov/41468178

https://www.liebertpub.com/doi/10.1177/25785125251410822


Medical Cannabis and Epilepsy: The Evidence

“Epilepsy is a serious neurological condition that can affect individuals of all ages. Treatment is far from perfect, and roughly 30% of patients can experience seizures that are resistant to antiseizure medications.

Interestingly, the cannabis plant, specifically the phytocannabinoids, cannabidiol and delta-9-tetrahydrocannabinol, has been shown to possess anticonvulsant properties and are effective in the treatment of seizures.

The clinical evidence base for cannabis for epileptic conditions has been growing in the last few decades with studies aiming to establish the clinical efficacy and safety profile of the plant. Despite the advancements that are being made, clinicians and medical regulatory bodies are still reluctant for epilepsy patients to use cannabis. Thus, it is essential that individuals are educated about the therapeutic properties of cannabis and the clinical evidence base to help patients gain access to cannabis medicines.”

https://pubmed.ncbi.nlm.nih.gov/41284246

“Evidence has shown that the plant possesses a range of therapeutic properties and has suggested its use as a potentially effective treatment for a variety of medical conditions. Consequently, the evidence base for the medicinal use of cannabis has been significantly growing over the years.”

https://www.magonlinelibrary.com/doi/full/10.12968/hmed.2024.0903