A Study to Investigate the Safety and Tolerability of Single and Multiple Ascending Doses of Antisense Oligonucleotide STK-001 in Children and Adolescents with Dravet Syndrome


About this study

The purpose of this study is to evaluate the safety and tolerability of single-ascending doses of STK-001 in patients with Dravet Syndrome.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Patient and/or authorized representative must be willing and able to give informed consent/assent and any authorizations required by local law for participation in the study.
  • Patient and their caregiver must be willing and able (in the Investigator’s opinion) to comply with all protocol requirements.
  • Patient must be between 2 and 18 years (inclusive) of age at Screening.
  • Patient must have DS as defined by:
    • Onset prior to 12 months of age with recurrent focal motor or hemiconvulsive or generalized tonic-clonic seizures, which are often prolonged and triggered by hyperthermia;
    • No past history of causal magnetic resonance imaging (MRI) lesion (MRI not required to confirm absence of lesion);
    • No other known etiology;
    • Normal development at seizure onset.
  • Patient must have a documented pathogenic, likely pathogenic variant, or variant of uncertain significance in the SCN1A gene. Patients who have SCN1A testing results of Negative (no variants of clinical significance identified) cannot be enrolled.
  • Patient has had at least 2 prior treatments for epilepsy that either had lack of adequate seizure control (requiring an additional antiepileptic drug [AED]) or had to be discontinued due to an AE(s).
  • Patient must be experiencing 4 or more convulsive seizures (Hemiclonic, Focal With Motor Signs, Focal To Bilateral Tonic Clonic Convulsion, Generalized Tonic Clonic Convulsion, Tonic, Tonic/Atonic [Drop Attacks], and Clonic) during the initial 28 days of the Observation Period.
  • Patient must currently be taking at least one AED at a dose which has been stable for at least 4 weeks prior to Screening.
  • All epilepsy medications or interventions for epilepsy (including ketogenic diet or vagal nerve stimulator) must have been stable (including product type, dose, and setting) for at least 4 weeks prior to Screening.
  • Any marijuana- or cannabinoid-based product or medication is allowed but treatment must have been stable for at least 4 weeks prior to Screening, including supplier, ratio, and dose.
  • Patient must meet age-appropriate institutional guidelines for intrathecal (IT) drug administration procedures.
  • Patient and/or family (or caretaker) must be sufficiently fluent in English or local language to be able to complete questionnaires relevant to this study.

Exclusion Criteria:

  • Patient has one of the following mutations in the SCN1A gene:
    • Thr226Met, Leu263Val, Val422Leu, Thr1174Ser, Trp1204Arg, Pro1345Ser, Gln1489Lys, Phe1499Leu, Arg1575Cys, Val1611Phe, Leu1624Pro, Arg1648Cys, Leu1649Gln, Leu1670Trp, Gly1674Arg, or Asp1866Tyr.
  • Patient has a known pathogenic mutation in another gene that causes epilepsy. (The pathogenic mutation must be homozygous in cases of known recessive disease).
  • Patient is currently being treated with an AED acting primarily as a sodium channel blocker, as maintenance treatment including:
    • phenytoin, carbamazepine, oxcarbazepine, lamotrigine, lacosamide, or rufinamide.
  • Patient has clinically significant unstable medical conditions other than epilepsy.
  • Patient has had clinically relevant symptoms or a clinically significant illness in the 4 weeks prior to Screening or prior to dosing on Day 1, other than epilepsy.
  • Patient has a history of brain or spinal cord disease (other than epilepsy or DS) or a history of bacterial meningitis or brain malformation.
  • Patient has a spinal deformity or other condition that may alter the free flow of CSF or has an implanted CSF drainage shunt.
  • Patient has clinically significant (in the judgment of the Investigator) abnormal laboratory values at Screening or prior to dosing on Day 1.
  • Patient  has  aspartate  aminotransferase  or  alanine aminotransferase > 2.5-fold upper limit of normal (ULN), serum creatinine > ULN or platelet count < lower limit of normal at Screening and upon repeat testing.
  • Patient has clinically relevant abnormalities in the 12-lead ECG measured at Screening or prior to dosing on Day -1.
  • Patient has a psychiatric or behavioral disorder which, in the opinion of the Investigator, may interfere with the patient’s participation in the study.
  • Patient is currently taking or within 4 weeks prior to Day 1, Visit 1 has taken any anticoagulant (including but not limited to heparins, warfarin and other vitamin K antagonists, dabigatran, rivaroxaban and apixaban), or within 7 days prior to Day 1, Visit 1 has taken any antiplatelet (including but not limited to aspirin, non-steroidal anti-inflammatory drugs, clopidogrel, ticlopidine. and dipyridamole).
  • Female patients of childbearing potential and male patients whose partner is of childbearing potential, unless willing to ensure that they or their partner use effective contraception, for example, abstinence, oral contraception, double barrier, or intra-uterine device during the study and for 3 months thereafter following the last dose of STK-001. Not applicable to patients with limited mental capacities who are incapable of sexual activity.
  • Female patient who is pregnant, lactating, or planning pregnancy during the course of the study and for 3 months thereafter.
  • Patient who is currently enrolled in or has been part of a blinded clinical study involving an investigational medicinal product within  2 months (or 5 half-lives, whichever is longer) prior to Screening.
  • Patient has any other significant disease or disorder which, in the opinion of the Investigator, may either put the patient at risk because of participation in the study, may influence the results of the study, or may affect the patient’s ability to participate in the study.

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Elaine Wirrell, M.D.

Open for enrollment

Contact information:

Bridget Neja C.N.A.

(507) 266-9150


More information


Publications are currently not available

Study Results Summary

Not yet available

Supplemental Study Information

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