Study to Evaluate the Safety and Microbiology of C16G2 in Adolescent and Adult Dental Subjects

The purpose of the clinical study is to evaluate the safety and microbiology of C16G2
administered in multiple oral gel doses to adolescent and adult dental subjects. Subjects
will be assigned to three study cohorts and receive 2 different volumes of C16G2 Gel or
Placebo. Prior to commencing enrollment of subjects 12-17 years of age, a safety only cohort
of 4-8 adolescent subjects will receive 4 study drug administrations on Day 0. A safety data
review will be performed by the Medical Monitor on Days 1 and 5. If no safety concerns are
identified, enrollment of adolescent subjects receiving 7 days of study drug administration
will be initiated in Study Arms 1 & 2. Enrollment of adult subjects in Study Arms 1 & 2 may
start before the Adolescent Safety Only Cohort is initiated. Before dosing of study drug,
eligible subjects will undergo professional dental prophylaxis on Day 0. Microbiology will be
assessed by measuring S. mutans and total bacteria counts.

Inclusion Criteria:

1. Adolescent Safety Only Cohort: Males and females, 12-17 years of age, inclusive, at
the time the Assent and Informed Consent Form is signed. Study Arms 1 & 2: Males and
females, 12-75 years of age, inclusive, at the time the Assent and/or Informed Consent
Form is signed

2. Female subjects of childbearing potential, defined as not surgically sterile or at
least two (2) years postmenopausal, must agree to use one of the following forms of
contraception from screening through the last study visit: hormonal (oral, implant, or
injection) begun >30 days prior to screening; barrier (condom, diaphragm, or cervical
cap with spermicide); intrauterine device (IUD). Acceptable contraceptive options may
also include abstinence, relationship with same sex partner or partner who has had a
vasectomy at least six (6) months prior to the screening visit

3. Male subjects only: willing to use contraception or abstain from sexual activity
beginning with the first exposure to study drug and continuing until discharged from
the study due to completion or Early Termination

4. Healthy, as determined by the Investigator, based on medical and dental history,
concurrent illnesses, laboratory results, concomitant medications, oral cavity
assessment, and targeted physical examination (extraoral, head and neck) during
Screening

5. Have a minimum of six unrestored bicuspids and molars with ≤50% of molars and
bicuspids having restorations, crowns, sealants or are missing

6. Demonstrated ability to expectorate ≥2mL of stimulated saliva in 5 minutes

7. Have a salivary S. mutans of 1.0 x 10e5 CFUs/mL or greater at Screening using MSB agar
plating

8. Willing to refrain from using non-study dentifrice and other non-study oral care
products (oral care rinses, fluoride products, etc.) during the study

9. Willing to postpone elective dental procedures (e.g., dental cleanings) between
Screening and final post-treatment visit

10. Willing and able to comply with oral hygiene and diet instructions

11. Has dentition adequate for custom dental tray gel application

12. Able to understand and sign the Assent and/or Informed Consent Form prior to
initiation of study procedures

13. Able to communicate with the Investigator/study center personnel, understand and
comply with the study requirements, and willing to return for protocol-specified
visits at the appointed times

Exclusion Criteria:

1. Advanced periodontal disease

2. Active caries lesion(s) within 30 days prior to study drug administration (confirmed
by comprehensive caries examination including standard radiographs); Note: Subjects
presenting with insipient, non-cavitated lesion(s) are not excluded

3. Medical condition (e.g., artificial heart valve, history of infective endocarditis,
cardiac transplant with valvular dysfunction, congenital heart disease or total joint
replacement) for which antibiotics are recommended prior to dental visits and/or
procedures

4. Pathologic lesions of the oral cavity

5. Full or partial dentures, or orthodontic appliances, e.g., night guards, permanent
retainers

6. Use of systemic antibiotics, topical oral antibiotics, or use of other drugs, which in
the opinion of the Investigator could influence the study outcome, within 30 days
prior to Screening

7. Medical history indicating the woman is pregnant, breastfeeding/ lactating or has a
positive urine pregnancy test

8. Participation in a clinical trial or receipt of a non-FDA approved therapy within 30
days prior to study drug administration

9. Prior participation in a C16G2 clinical trial and known to have received C16G2 active
gel or mouth rinse

10. Presence of any condition or concurrent illness, which in the opinion of the
Investigator, would compromise normal immune function, interfere with the use of study
dentifrice and oral care products, or interfere with the ability to comply with study
requirements, or jeopardize the safety of the subject or the validity of the study
results