A Study to Compare Sitavig (Acyclovir) Buccal Tablet With a Placebo in the Treatment of Herpes Labialis in Participants Whose Immune System Works Normally

NCT05098938 | Completed Phase 3 Results FDA Drug

• 1 other identifier: 21755
• Study Type: interventional
• Target: 2,020
• Locations: 1 country
• Sites: 1

Brief Summary

Researchers are looking for a better way to treat people who have recurrent herpes labialis, also known as cold sores. This is a type of viral infection that causes redness and blisters on the mouth and lip and that recurs. Herpes labialis is caused by a virus called the herpes simplex virus (HSV). The infection is spread when a person comes into direct contact with someone else who has the infection. Once a person becomes infected with HSV, the virus multiplies and spreads, which can cause redness and blistering on the mouth and lip. The blisters crust over and heal. Once healed, the virus is said to go into an "inactive" phase. This means the virus does not cause any symptoms, but still remains in the body. HSV can then become "active" again. This means causing cold sore lesions to reappear. HSV can become active in different ways. Some of these include when a person has a fever, comes into contact with strong sunlight or has a condition that lowers one's immune system It can also happen during a woman's menstrual cycle, also called a period. In this study, the researchers want to gather additional data on acyclovir 50 mg tablet, an available treatment for herpes labialis. It is a buccal tablet that sticks to the gum inside the mouth and directly treats the infected area to help stop the HSV from multiplying and spreading. In this study, the researchers want to compare the efficacy of acyclovir 50 mg buccal tablets versus placebo in the treatment of herpes labialis. A placebo is a treatment that looks like the study medicine but does not have any medicine in it. Study participants will include those who have had at least 4 episodes of herpes labialis within the past 12 months prior to joining the study. To compare the study treatments, the researchers will measure the "duration of episode" (DOE) for each participant. DOE is amount of time it takes for symptoms to disappear and for herpes labialis lesions to heal after taking the study treatment. A doctor will look at the participants' symptom scores and facial images to determine the DOE. Assessments will be done over a period of 14 days. The participants in this study will apply either acyclovir 50mg buccal tablet or the placebo as a tablet to the upper gum 1 time. There will be a 2 week treatment phase and a 12 month follow up phase. The participants in this study will not be required to visit the study site. Instead, the participants will have virtual meetings with the study doctors from their homes using the internet. During the treatment phase, there will be 2 meetings. Throughout the follow up phase, the doctors will call the participants 4 times. Each participant will be in the study for about 20 months. During the treatment phase of the study, the participants will:

• take their blood pressure and pulse
• check their mouth health through a questionnaire
• take pictures of their face and herpes labialis symptoms During the whole study the participants will answer questions about how they are feeling, what medications they are taking, and what adverse events they are having. The doctors will keep track of any adverse events. An adverse event is any medical problem that a participant has during a study. Doctors keep track of all adverse events that happen in studies, even if they do not think the adverse events might be related to the study treatments.

Conditions

Recurrent Herpes Labialis

Outcome Measures

Primary Outcomes (1)

• Duration of Episode (DOE) Was Measured in Hours (Using the Science 37 Platform), of a Single Treated Herpes Labialis (HL) Lesion

  Duration of episode (DOE) is defined as the time from the initiation of treatment (study intervention) to the healing of primary lesions (loss of crust) for participants who experience a vesicular lesion. For participants whose primary lesions are not vesicular in nature, duration of episode is the time from study intervention initiation to the return to normal skin as determined by the independent blinded reader of the participant's face images using a 6-point Likert scale or to the cessation of symptoms, whichever comes last.

  Up to 14 days

Secondary Outcomes (5)

• Incidence of Aborted Lesions

  Up to 14 days

• Incidence of Recurrence of HL Lesions During the 12-months Follow-up Period

  Up to 12 months

• Time to Recurrence of HL Lesions, Measured in Days From Resolution of the Cold Sore Treated in the Treatment Phase Until Onset of Prodromal Symptoms

  Up to 12 months

• Incidence of Treatment-Emergent Adverse Events (TEAE)s

  Up to 12 months

• Percentage of Participants Who Have at Least One Recurrence

  Up to 12 months

Study Arms (2)

Acyclovir 50mg buccal/topical tablet treatment group

EXPERIMENTAL

Drug: Acyclovir 50mg buccal/topical tablet, BAYM008894/UI1614773

Matching placebo group

PLACEBO COMPARATOR

Drug: Placebo

Interventions

Acyclovir 50mg buccal/topical tablet, BAYM008894/UI1614773 DRUG

Oral (upper gum area), 50mg, 1 tablet.

Acyclovir 50mg buccal/topical tablet treatment group

Placebo DRUG

Oral (upper gum area), 1 table.

Matching placebo group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Males or females, 18 years of age or older inclusive;
• History of recurrent HL lesions where:
• Recurrence is defined as at least 4 episodes in the preceding 12 months;
• At least half of the episodes should be vesicular in nature;
• At least half of the episodes should be preceded by prodromal symptoms;
• Herpes labialis lesions are characterized by their localization on the cutaneous and/or mucosal surfaces of the lips;
• Willing to avoid, during the treatment phase, the use of anti-inflammatory (not including low-dose (81 mg) aspirin), anti-herpetic, antibiotic and antiviral agents as well as steroids or other natural products that would interfere with the immune system response;
• Female participants of childbearing potential must be using a medically acceptable form of birth control during screening \[e.g., hormonal contraceptives (oral, patch, injectable or vaginal ring), implantable device (implantable rod or intrauterine device), or a double barrier\], abstinence or in same sex relationship and have a negative pregnancy test at Screening and prior to study drug administration. Female participants of non-childbearing potential must be amenorrheic for at least two years or have undergone surgical sterilization (i.e. tubal ligation/occlusion, hysterectomy and/or bilateral oophorectomy);
• Agreement to abstain from any mechanical disruption of the prodromal area or lesion (i.e. scrubbing, lancing, shaving the area, rubbing with alcohol, application of heat emitting devices used for cold sore treatment, etc.);
• Capable of giving signed informed consent as described in protocol which includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol;
• Ability to understand and follow study-related instructions;
• Be willing and able to participate in all scheduled visits, treatment plan, and trial procedures according to the clinical protocol.

You may not qualify if:

• Participants who did not develop herpes prodromal symptoms within 6 months after randomization in the study;
• More than 50% of recurrences that aborted spontaneously (without intervention) in the past 12 months;
• Primary herpes lesion outside the lips (e.g., nose, chin, etc.);
• Abnormal peri-oral skin condition that might affect the normal course of cold sores (e.g., eczema, psoriasis, etc.);
• Oral diseases whose prodromal symptoms may mimic those of herpes labialis, including recurrent oral aphthous disease;
• Allergy to any acyclovir or its containing agents;
• Milk allergy or known history of hypersensitivity to one of the components of Sitavig;
• Self-reported immunocompromised condition, including self-reported Human Immunodeficiency Virus (HIV) positive and previous bone marrow or organ transplant;
• Known medical history of renal disease, that in the judgment of the investigator is severe;
• Females who are planning to become pregnant, are pregnant or lactating.

Sponsors & Collaborators

• Bayer: lead

Study Sites (1)

Science 37

Culver City, California, 90230, United States

Location

MeSH Terms

Conditions

Herpes Labialis

Interventions

Acyclovir; Tablets

Condition Hierarchy (Ancestors)

Herpes Simplex; Herpesviridae Infections; DNA Virus Infections; Virus Diseases; Infections; Skin Diseases, Viral; Lip Diseases; Mouth Diseases; Stomatognathic Diseases; Skin Diseases, Infectious; Skin Diseases; Skin and Connective Tissue Diseases

Intervention Hierarchy (Ancestors)

Guanine; Hypoxanthines; Purinones; Purines; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Heterocyclic Compounds; Dosage Forms; Pharmaceutical Preparations

Limitations and Caveats

Initial results (Feb 2024) indicated significant data inconsistencies. After quality analysis of the data, it appears that the contract research organization (CRO) did not read the facial images correctly, which are the data source for the primary endpoint.

Results Point of Contact

• Title: Therapeutic Area Head
• Organization: Bayer

clinical-trials-contact@bayer.com

(+) 1-888-8422937

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: October 18, 2021
• First Posted: October 28, 2021
• Study Start: November 23, 2021
• Primary Completion: July 19, 2023
• Study Completion: July 2, 2024
• Last Updated: September 2, 2025
• Results First Posted: September 2, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)