Efficacy and tolerability of perampanel in ten patients with Lafora disease.

Lafora disease (LD) is a fatal intractable adolescence-onset progressive myoclonus epilepsy. Recently, two single-case studies reported drastic reductions in seizures and myoclonus with the AMPA antagonist perampanel and improved activities of daily living. We proceeded to study the effect of perampanel on 10 patients with genetically confirmed LD with disease duration ranging from 2 to 27years. Open-label perampanel was added to ongoing medications to a mean dose of 6.7mg/day. Seizures, myoclonus, functional disability, and cognition scores were measured for the third and ninth months following initiation and compared with those of the month prior to the start of therapy. Three patients withdrew because of inefficacy or side effects. Four had significant reduction in seizures of greater than 74% from baseline. Seven had major improvement in myoclonus with group-adjusted sum score of myoclonus intensity reduced from 7.01 at baseline to 5.67 and 5.18 at 3 and 9months, respectively. There was no significant improvement in disability and cognition. While not universal, perampanel adjunctive therapy appears to confer particular benefit not commonly seen with other antiepileptic drugs on seizures and myoclonus in LD. Improvement in the extremely disabling myoclonus of LD is a major benefit in this devastating disease.

PTG protein depletion rescues malin-deficient Lafora disease in mouse.

Ubiquitin ligases regulate quantities and activities of target proteins, often pleiotropically. The malin ubiquitin E3 ligase is reported to regulate autophagy, the misfolded protein response, microRNA silencing, Wnt signaling, neuronatin-mediated endoplasmic reticulum stress, and the laforin glycogen phosphatase. Malin deficiency causes Lafora disease, pathologically characterized by neurodegeneration and accumulations of malformed glycogen (Lafora bodies). We show that reducing glycogen production in malin-deficient mice by genetically removing PTG, a glycogen synthesis activator protein, nearly completely eliminates Lafora bodies and rescues the neurodegeneration, myoclonus, seizure susceptibility, and behavioral abnormality. Glycogen synthesis downregulation is a potential therapy for the fatal adolescence onset epilepsy Lafora disease.

A pan-respiratory antiviral chemotype targeting a transient host multi-protein complex.

We present a novel small molecule antiviral chemotype that was identified by an unconventional cell-free protein synthesis and assembly-based phenotypic screen for modulation of viral capsid assembly. Activity of PAV-431, a representative compound from the series, has been validated against infectious viruses in multiple cell culture models for all six families of viruses causing most respiratory diseases in humans. In animals, this chemotype has been demonstrated efficacious for porcine epidemic diarrhoea virus (a coronavirus) and respiratory syncytial virus (a paramyxovirus). PAV-431 is shown to bind to the protein 14-3-3, a known allosteric modulator. However, it only appears to target the small subset of 14-3-3 which is present in a dynamic multi-protein complex whose components include proteins implicated in viral life cycles and in innate immunity. The composition of this target multi-protein complex appears to be modified upon viral infection and largely restored by PAV-431 treatment. An advanced analog, PAV-104, is shown to be selective for the virally modified target, thereby avoiding host toxicity. Our findings suggest a new paradigm for understanding, and drugging, the host-virus interface, which leads to a new clinical therapeutic strategy for treatment of respiratory viral disease.

A Pan-respiratory Antiviral Chemotype Targeting a Transient Host Multiprotein Complex.

We present a small molecule chemotype, identified by an orthogonal drug screen, exhibiting nanomolar activity against members of all the six viral families causing most human respiratory viral disease, with a demonstrated barrier to resistance development. Antiviral activity is shown in mammalian cells, including human primary bronchial epithelial cells cultured to an air-liquid interface and infected with SARS-CoV-2. In animals, efficacy of early compounds in the lead series is shown by survival (for a coronavirus) and viral load (for a paramyxovirus). The drug target is shown to include a subset of the protein 14-3-3 within a transient host multi-protein complex containing components implicated in viral lifecycles and in innate immunity. This multi-protein complex is modified upon viral infection and largely restored by drug treatment. Our findings suggest a new clinical therapeutic strategy for early treatment upon upper respiratory viral infection to prevent progression to lower respiratory tract or systemic disease. One Sentence Summary: A host-targeted drug to treat all respiratory viruses without viral resistance development.

Extraneurological sparing in long-lived typical Lafora disease.

Lafora disease (LD) clinically appears in previously healthy teenagers as progressively worsening seizures, myoclonus, dementia, and ultimately a vegetative state leading to death within a decade of its onset. Here we present a typical case of LD in which the patient survived until the age of 40. Although the patient's brain was severely affected, other organs remained functional until her death. The field of LD research is approaching potentially curative therapies (eg, with antisense oligonucleotides or gene replacement) targeting only the central nervous system (CNS). Our case provides anecdotal evidence suggesting that a patient with typical LD can retain full bodily health aside from the effects of neurological damage.