Proof of Concept Study to Assess Activity and Safety of SMT C1100 (Ezutromid) in Boys With Duchenne Muscular Dystrophy (DMD)

Exclusion Criteria

• •Have physical exam findings that in the Investigator's opinion should be exclusionary e.g., lower limb injury that may affect 6MWD performance.
• •Have any change (initiation, change in type of drug, dose modification, schedule modification, interruption, discontinuation or reinitiation) in prophylaxis/treatment for congestive heart failure (CHF) within 3 months prior to the start of study treatment.
• •Have uncontrolled clinical symptoms and signs of CHF (American College of Cardiology/American Heart Association Stage C or Stage D).
• •Have abnormal glutamate dehydrogenase (GLDH) at baseline (\>1.5 x upper limit of normal \[ULN\]).
• •Have abnormal coagulation times at baseline (\>1.5 x ULN).
• •Have an abnormal electrocardiograms (ECG).
• •Use herbal supplements and be unwilling to stop these for the duration of the study.
• •Have been exposed to another investigational drug or DMD interventional agent within 3 months prior to start of the Treatment Phase. Prior exposure to SMT C1100 or participation in an approved deflazacort access program within this period would not exclude the participant (provided they have been on stable treatment for 6 months).
• •Have a history of major surgical procedure within 12 weeks prior to the start of the Treatment Phase (Week 1).
• •Be undertaking ongoing immunosuppressive therapy (other than corticosteroids).
• •Require daytime ventilator assistance.
• •Have a prior or ongoing medical condition, medical history, ECG findings, or laboratory abnormality that, in the Investigator's opinion, could adversely affect the safety of the participant, makes it unlikely that the course of treatment or follow-up would be completed, or could impair the assessment of study results.
• •Be dairy or lactose intolerant or have any other dietary restrictions that might interfere with the conduct of the study.
• •Be a smoker, use other tobacco or nicotine products or be exposed to daily passive smoking (including parent/legal guardian, siblings) so as to minimise environmental factors causing CYP1A induction.
• •Be using an approved DMD medication or anticipates using one during the duration of the study. Participants who are taking part in the FOR-DMD and ACCESS DMD studies will be allowed to take part.
• •Be using an inducer of CYP1A1 or CYP1A2.
• •Be using a substrate of CYP2B6.
• •All prescription, over the counter, and herbal products that are known CYP2B6 sensitive substrates will be excluded 14 days prior to study conduct (beginning at screening) through 14 days after study conduct completion. Please note, this is not an exhaustive list of CYP2B6 substrates and a discussion with the Medical Monitor may be warranted.
• •Be using drugs that have serotonergic, norepinephrinergic or dopaminergic activity, or treatments used in attention deficit hyperactivity disorder.
• •Use of substrates of BRCP.
• •Use beta blockers (however, if during the course of the study they are clinically indicated they can be initiated).
• •Have a known hypersensitivity to any of the ingredients or excipients of the investigational medicinal product: Poloxamer 188, Methylparaben, Propylparaben, Hydroxypropylmethyl cellulose, Glycerol, Non-crystallising sorbitol \[70%\], Xanthan gum, Strawberry cream flavour \[PHS-132963\].
• •Have a known hypersensitivity to any of the ingredients or excipients of the investigational medicinal product: hypromellose acetate succinate.