Study to Evaluate Efficacy, Safety, and Tolerability of MT‑7117 in Subjects With Erythropoietic Protoporphyria

This is a Phase 2, randomized, double-blind, placebo controlled study to assess the efficacy,
tolerability, and safety of MT-7117 in subjects with EPP. The study consists of a 2 week
screening period, a 16 week double-blind treatment period, and a 6 week follow-up period at
Week 22. The total participation period is approximately 24 weeks.

Additional screening criteria check may apply for qualification.

Inclusion Criteria:

- 1. Subjects provided written informed consent to participate.

- 2. Male and female subjects with a confirmed diagnosis of EPP based on medical
history, aged 18 years to 75 years, inclusive, at Screening.

- 3. Subjects are willing and able to travel to the study sites for all scheduled
visits.

- 4. In the Investigator's opinion, subject is able to understand the nature of the
study and any risks involved in participation, and willing to cooperate and comply
with the protocol restrictions and requirements (including travel).

Exclusion Criteria:

- 1. History or presence of photodermatoses other than EPP.

- 2. Subjects who are unwilling or unable to go outside during daylight hours (e.g.,
between 1 hour post sunrise and 1 hour pre-sunset) during the study.

- 3. Presence of clinically significant hepatobiliary disease based on medical history
or LFT values at Screening.

- 4. Subjects with AST, ALT, ALP ≥3.0 × upper limit of normal (ULN) or total bilirubin
≥1.5 × ULN at Screening.

- 5. Subjects with or having a history (in the last 2 years) of excessive alcohol intake
in the opinion of the Investigator.

- 6. History or presence of melanoma and/or atypical nevus at Screening.

- 7. History of familial melanoma (defined as having 2 or more first-degree relatives,
such as parents, sibling and/or child).

- 8. History or presence of pre-malignant skin lesion squamous cell carcinoma, basal
cell carcinoma, or other pre malignant.

- 9. History or presence of psychiatric disease judged to be clinically significant by
the Investigator and which may interfere with the study evaluation and/or safety of
the subjects.

- 10. Presence of clinically significant acute or chronic renal disease based upon the
subject's medical records including hemodialysis; and a serum creatinine level of
greater than 1.2 mg/dL or a glomerular filtration rate (GFR) <60 ml/min.

- 11. Presence of any clinically significant disease or laboratory abnormality which, in
the opinion of the Investigator, can interfere with the study objectives and/or safety
of the subjects.

- 12. Pregnancy or lactation.

- 13. Females of child bearing potential and male subjects with partners of
child-bearing potential unwilling to use adequate contraception measures as described
in the protocol.

- 14. Treatment with phototherapy within 3 months before Randomization (Visit 2).

- 15. Treatment with afamelanotide within 3 months before Randomization (Visit 2).

- 16. Treatment with cimetidine within 4 weeks before Randomization (Visit 2).

- 17. Treatment with antioxidant agents at doses which, in the opinion of the
Investigator, may affect study endpoints (including but not limited to beta-carotene,
cysteine, pyridoxine) within 4 weeks before Randomization (Visit 2).

- 18. Chronic treatment with prescription-based analgesic agents including but not
limited to opioids and opioid derivatives such as morphine, hydrocodone, oxycodone or
their combination with other analgesics or non-steroidal anti-inflammatory drug
(NSAID, as Percocet and Vicodin-like prescription drugs) within 4 weeks before
Randomization (Visit 2).

- 19. Treatment with any drugs or supplements which, in the opinion of the Investigator,
can interfere with the objectives of the study or safety of the subjects.

- 20. Previous exposure to MT 7117.

- 21. Previous treatment with any investigational agent within 12 weeks before Screening
OR 5 half-lives of the investigational product (whichever is longer).