Study of Arimoclomol in Inclusion Body Myositis (IBM)

Inclusion Criteria:

- Meet any of the European Neuromuscular Centre Inclusion Body Myositis research
diagnostic criteria 2011 categories for IBM

- Demonstrate being able to arise from a chair without support from another person or
device

- Able to ambulate at least 20 ft/6 meters with or without assistive device. Once arisen
from the chair, participant may use any walking device, i.e. walker/frame, can,
crutches, or braces. They cannot be supported by another person and cannot use
furniture or wall for support.

- Body weight of >= 40 kg

- Pre-menopausal women must have a negative pregnancy tst prior to dosing iwht study
medication.

- If a participant in the bimagrumab study, the participant must be off of the study
medication for at least 6 months.

- Able to give informed consent

Exclusion Criteria:

- History of any of the following excludes subject participation in the study: chronic
infection particularly HIV or Hepatitis B or C; cancer other than basal cell cancer
less than five years prior; or other chronic serious medical illnesses.

- Presence of any of the following on routine blood screening: WEB <3000; platelets <
100,000; hematocrit , 30%; BUN > 30 mg%; creatinine > 1.5 mg%; symptomatic liver
disease with serum albumin < 3 g/dL.

- History of most recent creatine kinase >15x the upper limit of normal without any
other explanation besides IBM.

- History of non-compliance with other therapies

- Use of testosterone except for physiologic replacement doses in case of androgen
deficiency. Participants must have documented proof of the androgen deficiency.

- Coexistence of other disease that would be likely to affect outcome measures.

- Drug or alcohol abuse within past three months

- Participation in a recent drug study in the last 30 days prior to the screening visit
or use of a biologic agent less than 6 months prior to the screening visit.

- Women who are lactating or unwilling to use adequate method of birth control who are
not surgically sterile. Adequate birth control includes use of intrauterine device,
abstinence, or oral contraceptives or a double barrier method, e.g condom plas
diaphragm will be necessary for both male and female participants.

- Participants taking >7.5 mg prednisolone or equivalent or participants on IVIg or
other immunosuppressants within the last 3 months.