Safety and Tolerability of Antiplaque Chewing Gum in a Gingivitis Population

This study is a Phase 1/2a placebo-controlled, double-blind, randomized, dose-escalation
study to evaluate the safety and proof of concept of Antiplaque Chewing Gum. This is a 2-part
trial with 9 dosing cohorts in Phase 1 and 7 dosing cohorts in Phase 2a. For both phases, the
oral soft (OST) and oral hard tissues (OHT) will be examined. Changes from baseline, such as
soft tissue erythema, ulceration and sloughing, will be noted and assessments will be made by
the principal investigator as to whether they might be attributable to the antiplaque chewing
gum.

In the Phase 2a portion of the study, the efficacy of the antiplaque chewing gum in reducing
existing supragingival plaque and gingivitis will also be assessed. Plaque will be assessed
using the Turesky Modification of the Quigley-Hein Plaque Index (PI, Turesky et al-1970) and
gingivitis will be assessed using both the Modified Gingival Index (MGI, Lobene et al-1986)
and the percent of bleeding sites on gentle probing (BOP) using the methods described in
Ainamo and Bay-1975.

Inclusion Criteria:

Subjects must meet all of the following criteria to be included in the Phase 1 portion of
the study:

- Males and females between 18 and 64 years of age

- A negative urine pregnancy test and willingness to use a reliable form of
contraception for the duration of the study (females of childbearing potential only),
with reliable contraception defined as:

Abstinence Oral contraceptive, either estrogen progesterone combined, or progesterone alone
Injectable progesterone Implants of levonorgestrel Estrogenic vaginal ring Percutaneous
contraceptive patches Intrauterine device or intrauterine system Double barrier method
[condom or occlusive cap (diaphragm or cervical vault caps) plus spermicidal agent (foam,
gel, film, cream, suppository)] Male partner sterilization prior to the female subject's
entry into the study, and this male is the sole partner for that subject

- Good health, as determined by pertinent medical history, physical examination, vital
signs, and clinical safety laboratory evaluations

- A minimum of 16 natural teeth with 2 scorable surfaces (facial and lingual) per tooth
Sufficient number of opposing posterior teeth to chew on both sides of the mouth as
determined by the examining dentist Teeth that have gross caries, full crowns or
extensive restorations on facial and/or lingual surfaces, orthodontic bands, and third
molars are not included in the tooth count

- Ability to comprehend and a willingness to sign an informed consent, which includes
the Authorization for the Release of Health Information document

- Willingness to comply with all study procedures

Phase 2a Inclusion Criteria

Subjects must meet all the criteria for the phase 1 portion of the study, and in addition
must:

- Have mild to moderate gingivitis and plaque MGI of 1.8 or greater (Ainamo and
Bay-1975) PI of 1.95 or greater (Turesky et al-1970)

- Willing to forgo any optional dental procedures during the study period, such as
dental prophylaxis or teeth whitening

Exclusion Criteria:

Subjects meeting any of the following criteria will be excluded from the study:

- Acute or chronic medical conditions, organ system disease, or medications that, in the
principal investigator's opinion, would impair the subject's ability to participate

- TMD

- Self-reported use of tobacco products

- Use of anticoagulant medications (eg clopidogrel)

- Gross oral pathology, including widespread caries or chronic neglect, extensive
restoration, pre-existing gross plaque or calculus, or soft or hard tissue tumor of
the oral cavity

- Orthodontic appliances or removable partial dentures that will compromise the ability
of the potential subject to participate in the study

- Periodontitis as indicated periodontal pockets greater than 4 millimeters on more than
one site

- Receipt of any investigational drug/test product within 30 days prior to study entry

- Receipt of antibiotics within 30 days prior to study entry

- Need for antibiotic prophylaxis prior to invasive dental procedures

- Receipt of daily anti-inflammatory therapy [eg nonsteroidal anti-inflammatory drugs
(NSAID), tumor necrosis factor (TNF) alpha blockers] within 30 days prior to study
entry

- Receipt of prescription antibacterial oral products (eg products containing
chlorhexidine) within 30 days prior to study entry

- Pregnant or breast-feeding female

- Clinically significant abnormal laboratory tests as determined by the principal
investigator

- An employee of the study site directly involved with the study

- Inability to comply with assigned treatment regimen