SynRinse Irrigation Pilot (SIP) Trial

SYNRINSE is osmotically balanced and also contains soluble chitosan-argininamide, a modified
natural glycopolymer that has a number of properties important to relieving the symptoms of
mucus build up and bacterial biofilms. First, SYNRINSE reduces the viscosity of biofilms, the
protective environment of infective bacteria that prevents topical antibiotics and other
rinses to penetrate to reach the bacterial. By disrupting biofilms, SYNRINSE allows them to
be cleared from the sinuses. Second, SYNRINSE has been shown to interact with the polymers
comprise mucus, loosening thick, sticky layers and reducing their ability to adhere together
and to mucosal surfaces. Third, all of the components in SYNRINSE are biocompatible and
soothing to sensitive nasal cavities.

Inclusion Criteria:

- age >= 18

- Meet diagnostic criteria for CRS (as defined by the AAO-HNS 2015 Clinical Practice
Guidelines for Adult Sinusitis).

- Have undergone at least one functional endoscopic sinus surgery, be at least 6 weeks
out from surgery, be free of any complication from surgery, and have patent sinuses
confirmed by nasal endoscopy.

- Have active sinus disease as defined as purulent sinus discharge visualized on nasal
endoscopy.

- Have more than mild symptoms as determined by the SNOT-22 with a score >20.

- Be willing to hold off on standard therapy for chronic sinusitis for 1 week including
oral antibiotics and/or oral steroids.

- If on topical steroids for greater than 1 month (sprays, drops, or irrigation) these
will be continued based on the patients' current use (continued if they are already on
them, not initiated if they are not on them).

- Must be able to irrigate with large volume/low pressure nasal lavage throughout the
study.

Exclusion Criteria

:• Have an allergy to shell fish.

- Be able to return for follow up evaluation in 1 week (+ up to 5 days if needed)

- Have obstructive nasal polyps

- Participants who have used topical antibiotics within 4 weeks of treatment or are
actively using them and unwilling to stop

- Participants who have used systemic steroids within 4 weeks of treatment

- Are unable to give informed consent or complete self-administered questionnaires
written in English because of cognitive impairment, language barrier, or severe
medical conditions.

- Have a terminal illness or significant immune dysfunction.

- Have severe or emergent complications from CRS or presence of a sinus tumor.

- Patients with Cystic Fibrosis will be recruited in a parallel study.

- Participants who are unwilling to discontinue other sinus irrigations treatments and
steroid lavage if already on them (including baby shampoo, surfactant, colloid silver,
manuka honey, iodine, alcohol, tea tree oil, or any other compound).