Study to Assess Safety and Clinical Activity of Local MBN-101 in Treatment of Infected Bone Sites

Postoperative orthopaedic infections, particularly antibiotic-resistant infections, present a
serious clinical challenge to surgeons and other treating physicians. These infections
frequently involve implanted foreign materials (stabilizing orthopaedic hardware), making
infection of these sites much more likely than if foreign materials were not involved.
MBN-101 has broad spectrum antimicrobial activity against orthopaedic wound pathogens.

This is a randomized, single-blind, placebo-controlled, multi-center study to assess the
safety and tolerability of escalating doses of MBN-101 to treat orthopaedic infections during
revision surgery, (a) with or without orthopaedic hardware, and (b) with or without removal
and replacement of orthopaedic hardware.

Inclusion Criteria:

- To be eligible for this study, each of the following criteria must be satisfied with a
"YES" answer (unless not applicable):

Patients who:

- have had operative fracture fixation of the upper extremity (AO/OTA class 15, 11-13,
21-23), lower extremity (AO/OTA class 31-34, 41 44, 81, 82) or pelvis (61, 62), or
have undergone arthrodesis, and have subsequently been diagnosed with an apparent
fracture site infection or are diagnosed with chronic or acute-on-chronic
osteomyelitis of the long bone extremities (including residual amputated limbs)

- have at least one of the following:

- require surgical debridement of infected soft tissue and/or bone, with or without
removal and/or placement/replacement of hardware

- male or female between the ages of 18 and 75 at the time the ICF is reviewed and
signed

- patients receiving or anticipated to receive systemic antibiotic therapy as per
institution's standard of care

- patients requiring postoperative hospitalization for at least 48 hours after revision
surgery

- have read and signed the Informed Consent Form (ICF) after the nature of the study has
been fully explained

- be willing and able to provide authorization for use and disclosure of personal health
information in accordance with the Health Insurance Portability and Accountability Act
(HIPAA)

Exclusion Criteria:

- To be eligible for this study, each of the following criteria must be satisfied with a
"NO" answer (unless not applicable):

- Patients who are no longer hardware dependent or are definitively treated for
their infection by hardware removal without replacement

- Patients with multiple, non-contiguous sites of infection

- Pathologic fracture (not including osteoporosis)

- Patient requires immunosuppressive therapy (Topical or inhaled corticosteroids
are permitted)

- Serum creatinine, ALT, AST or Alkaline Phosphatase >2.0 times the upper limit of
the normal range of the local testing laboratory

- Absolute neutrophil count <1000

- Patients without definitive soft-tissue coverage over the surgical site at time
of study product administration

- Any condition that has required treatment with any other bismuth containing
compound within the last 2 weeks (i.e., Kaopectate or Pepto Bismol)

- Participation in an investigational trial to evaluate pharmaceuticals or
biologics within the past 3 months

- Individuals undergoing surgical treatment for more than one infected site

- Patients who are pregnant, lactating, or female patients who have a positive
serum hCG (human Chorionic Gonadotropin) as determined by laboratory testing

- Immunocompromised due to illness or organ transplant

- History of chronic or recurrent infections (≥ 3 infections at the same site
within 12 months)

- History of any type of cancer (excluding non-melanomatous localized skin cancer
or completely excised and cured carcinoma-in-situ of uterine cervix)

- Poorly controlled diabetes mellitus

- History of medical noncompliance

- Other medical conditions which, in the opinion of the Principal Investigator,
would jeopardize the safety of the study subject or impact the validity of the
study results.

- Current incarceration