HT-100 Long-term Study in DMD Patients Who Completed HALO-DMD-02

As a follow-on study to the initial clinical studies of HT-100 in DMD (Protocols HALO-DMD-01
and HALO-DMD-02), this open-label study is designed to provide data on continuous long-term
dosing. Subjects will be entered into the study without cessation of dosing, in a staggered
fashion, into the same cohort assignment they had in the predecessor studies. Up to 30
subjects who have completed dosing in HALO-DMD-02 will be offered the opportunity to continue
on the same dose regimen until market approval of HT-100 or termination of the study by the
Sponsor. Reasons for termination could include, among others, safety concerns or lack of
efficacy, based on analysis of combined data from all HT-100 studies. Safety data from
subjects approaching the end the HALO-DMD-02 participation will be individually reviewed by
the Medical Monitor and the subject's physician (Principal Investigator [PI]). If the Medical
Monitor and the PI agree there are no clinically significant safety signals (absence of
clinically significant laboratory or clinical abnormalities to date), the subject will be
considered eligible and offered continuation of dosing. To avoid an interruption in dosing,
subjects will immediately be screened for participation and enrolled upon completing the
predecessor trial, HALO-DMD-02. Participation is in this study HALO-DMD-03 is optional.
Safety and pharmacodynamics (PD) monitoring will continue throughout the subject's study
participation. Dose reduction/modification might occur or individual subjects' participation
in the trial may be discontinued if any Adverse Events (AEs) suggest that HT-100 is not
sufficiently well tolerated.

Inclusion Criteria:

1. Completed both previous studies HALO-DMD-01 and HALO-DMD-02

2. Ability to provide written informed consent

3. Ability to understand and follow site and protocol instruction for the entire duration
of the study

Exclusion Criteria:

Answering yes to any of the following make the subject NOT eligible to participate in the
study.

1. Clinically significant major disease not related to DMD that would make it not safe to
be in the study or affect ability to follow the protocol

2. History of severe allergic or anaphylactic reactions

3. Recent report of drug/alcohol abuse