Safety and Acceptability of Q GRFT Nasal Spray for COVID-19 Prophylaxis

Inclusion Criteria: * Willing and able to provide written informed consent * In general good health as determined by the site clinician * Negative SARS-CoV-2 test at screening * Fully vaccinated for SARS-CoV-2 (does not include booster vaccination) * Agree to abstain from any other investigational drug studies for the duration of the study * Agree to abstain from nasally administered products, including over-the-counter products, for the duration of the study * Report use of an effective method of contraception at enrollment and intending to continue use of an effective method for the duration of study participation. Acceptable methods include: 1. Males: Male condoms, sterilization of participant or partner, partner use of hormonal contraception or intrauterine device, identifies as a man who has sex with men exclusively, and/or sexually abstinent for the past 60 days and agrees to remain abstinent for the study duration 2. Females: Hormonal methods at the time of enrollment, intrauterine device inserted prior to enrollment, sterilization of participant or partner, consistent condom use of male partner for at least 28 days (reports using condoms 10 times in the last 10 acts of intercourse), identifies as a woman who has sex with women exclusively, and/or sexually abstinent for the past 60 days and agrees to remain abstinent for the study duration. * Agree to participate in all study-related assessments and procedures Exclusion Criteria: * Abnormal nasal or throat exam at enrollment * If female, pregnancy, or within 42 days of last pregnancy at screening * If female, breastfeeding * Diagnosed with SARS-CoV-2 in the past 42 days at screening * Diagnosed or suspected respiratory tract infection in the past 14 days at screening (including asymptomatic SARS-CoV-2) * Participation in an investigational drug study in past 30 days at screening * Any condition that, in the opinion of the Investigator would preclude provision of consent, make participation in the study unsafe, complicate interpretation of study outcome data, or otherwise interfere with achieving the study objectives * Use of any intranasal product in the 14 days prior to enrollment * Surgical procedure involving the nose or throat 90 days prior to enrollment * Any of the following laboratory abnormalities at screening: 1. Hgb \< 12g/dL (men) and \< 11g/dL (women) 2. Serum creatinine \> 1.1 x upper limit of normal 3. alanine transaminase, aspartate aminotransferase, and total bilirubin \> 1.1 x upper limit of normal * Grade 2 or higher seasonal allergies at the time of enrollment * Reported use of illicit drugs 1. Non-therapeutic injection drug use in the 12 months prior to screening 2. Any use of methamphetamine, gamma hydroxybutyrate, cocaine or heroin in the 12 months prior to screening * Use of systemic prescription immunomodulatory medications within the 4 weeks prior to the enrollment