A Phase 2b Study of SPI-1005 to Prevent Acute Noise Induced Hearing Loss

Randomized, double-blind, placebo-controlled, safety and efficacy study of oral SPI-1005 in
adults with Noise Induced Hearing Loss (NIHL). All recruited subjects will have their
severity of NIHL determined before the start of SPI-1005 treatment using various hearing
tests. Subjects will be enrolled and randomized to either placebo or SPI-1005. Subjects will
be dosed with either placebo or SPI-1005 for 7 days, beginning 1 day before an acute NIHL.
Subjects will have hearing tests performed before and immediately after a calibrated sound
challenge (CSC). Follow-up hearing tests will be performed post-CSC.

Inclusion Criteria:

- Adult male or female patients, 18-50 years of age

- History of either recreational and/or occupational exposure to noise

- Voluntarily consent to participate in the study

- Females of childbearing potential should be using and committed to continue using one
of the following acceptable birth control methods: Sexual abstinence (inactivity) for
14 days prior to screening through study completion; or intra-uterine device in place
for at least 3 months prior to study through study completion; or barrier method
(condom or diaphragm) with spermicide for at least 14 days prior to screening through
study completion; or stable hormonal contraceptive for at least 3 months prior to
study through study completion; or surgical sterilization (vasectomy) of partner at
least 6 months prior to study.

- Females of non-childbearing potential should be surgically sterile (bilateral tubal
ligation with surgery at least 6 months prior to study, hysterectomy, or bilateral
oophorectomy at least 2 months prior to study) or be at least 3 years since last
menses.

Exclusion Criteria:

- Current use or within 60 days prior to study of excluded ototoxic medications

- History of autoimmune inner ear disease

- History of middle ear or inner ear surgery

- Current conductive hearing loss or middle ear effusion

- Significant cardiovascular, pulmonary, hepatic, renal, hematologic, gastrointestinal,
endocrine, immunologic, or psychiatric disease

- History of hypersensitivity or idiosyncratic reaction to compounds related to ebselen

- Current use or within 30 days prior to study of drugs or substances known to be strong
inhibitors or inducers of cytochrome P450 enzymes

- Participation in another investigational drug or device study within 90 days prior to
study enrollment

- Female patients who are pregnant or breastfeeding