8-K: Stoke Therapeutics Announces Landmark Data for STK-001 in Dravet Syndrome Treatment

Stoke Therapeutics reports significant and sustained reductions in seizure frequency and improvements in cognition and behavior in Dravet syndrome patients treated with STK-001.

Summary

• Stoke Therapeutics has released new data from Phase 1/2a and open-label extension studies of STK-001 for Dravet syndrome.
• The 70mg dose of STK-001 showed a median reduction in convulsive seizure frequency of 85% at 3 months and 74% at 6 months after the last dose.
• Open-label extension studies showed durable reductions in seizures and clinically meaningful improvements in cognition and behavior over 12 months with 30mg and 45mg doses.
• The company plans to meet with regulatory agencies to discuss a registrational study using initial 70mg doses followed by 45mg maintenance doses.
• STK-001 has been generally well-tolerated in studies to date.
• The FDA has cleared patients to receive three doses of 70mg followed by continued dosing at 45mg.

Sentiment

Score: 9

Explanation: The document presents very positive clinical trial results with significant reductions in seizures and improvements in cognition and behavior, suggesting a potential breakthrough in Dravet syndrome treatment. The company is moving forward with regulatory discussions, indicating strong confidence in the drug's potential.

Positives

• STK-001 showed substantial and sustained reductions in seizure frequency, with a median reduction of 85% at 3 months and 74% at 6 months after the last 70mg dose.
• Open-label extension studies demonstrated durable reductions in seizures and clinically meaningful improvements in cognition and behavior over 12 months with 30mg and 45mg doses.
• The treatment was generally well-tolerated across the Phase 1/2a and open-label extension studies.
• The FDA has cleared patients to receive three doses of 70mg followed by continued dosing at 45mg.
• The data suggests STK-001 has the potential to be a disease-modifying therapy for Dravet syndrome.

Negatives

• Some patients experienced treatment-emergent adverse events, including CSF protein elevations and procedural vomiting.
• A greater incidence of CSF protein elevation was observed in the open-label extension studies, with 74% of patients having at least one CSF protein value >50 mg/dL, although no clinical manifestations were observed.
• One patient discontinued treatment due to elevated CSF protein.

Risks

• There are risks and uncertainties related to the company's ability to advance, obtain regulatory approval of, and commercialize STK-001.
• Positive results in clinical trials may not be replicated in subsequent trials.
• The company's ability to fund development activities and achieve development goals into 2025 is a risk.
• Global business, political, and macroeconomic conditions could impact the company's results.

Future Outlook

The company plans to meet with regulatory agencies to discuss a registrational study design using initial 70mg doses followed by 45mg maintenance doses and expects to provide an update later in 2024.

Management Comments

• Edward M. Kaye, M.D., Chief Executive Officer, stated that the data supports the potential for STK-001 to be a disease-modifying medicine for Dravet syndrome.
• Joseph Sullivan, M.D., FAES, noted that an 80% reduction in seizures on top of existing anti-seizure medications is profound and that improvements in cognition and behavior distinguish this approach from others.

Industry Context

This announcement is significant as there are currently no approved disease-modifying therapies for Dravet syndrome, and STK-001 is the first medicine in development to demonstrate substantial and durable reductions in seizure frequency and improvements in cognition and behavior.

Comparison to Industry Standards

• The 85% median reduction in seizure frequency at 3 months and 74% at 6 months with STK-001 is significantly higher than the 50% reduction often considered clinically meaningful in epilepsy trials.
• The improvements in cognition and behavior observed in the open-label extension studies are in stark contrast to natural history data, which show no meaningful improvement in these areas despite treatment with the best available anti-seizure medicines.
• Current treatments for Dravet syndrome primarily focus on controlling seizures, while STK-001 aims to address the underlying genetic cause, a novel approach compared to existing therapies.

Stakeholder Impact

• Shareholders are likely to react positively to the strong clinical data and the potential for STK-001 to become a disease-modifying therapy.
• Patients and their families may have increased hope for a more effective treatment for Dravet syndrome.
• Employees may be motivated by the positive results and the potential to make a significant impact on patients' lives.

Next Steps

• The company will meet with regulatory agencies to discuss the design of a registrational study.
• The company plans to provide an update following those discussions later in 2024.

Key Dates

Keywords

Dravet syndrome, STK-001, seizure reduction, cognition, behavior, RNA-based medicine, clinical trial, disease-modifying therapy, antisense oligonucleotide, NaV1.1 protein