New Drug
Johanna Taylor Katroscik, PharmD
In October 2021, FDA announced the approval of Tyrvaya, a first-in-class medication to treat the signs and symptoms of dry eye disease. Tyrvaya is a new formulation of varenicline, a drug used as a smoking cessation aid. Unlike the oral formulations, which are used for smoking cessation, Tyrvaya is a nasal spray and is only used for treatment of dry eye disease.
The Mayo Clinic defines dry eye disease as “a common condition that occurs when your tears aren’t able to provide adequate lubrication for your eyes.” Symptoms often include a stinging or burning sensation in the eyes, eye redness, and watery eyes. Dry eye disease may be diagnosed using a number of different tests or procedures, including a comprehensive eye exam, a test to measure the volume or quality of tears produced, or a tear osmolarity test. Treatments are often dependent on the cause of dry eye disease. For some, OTC lubricating eye drops may be enough; others may require prescription medications to treat underlying eye conditions causing the eyes to become dry and irritated.
Recommended dosage and how it works
Tyrvaya is supplied as a nasal spray that delivers 0.03 mg varenicline per 0.5 mL in each actuation. The recommended dose is one spray in each nostril twice daily.
The exact mechanism of action of Tyrvaya on dry eye disease is unknown. Varenicline can act as both a partial and full nicotinic acetylcholine receptor agonist (partial or full agonist effect is dependent upon the specific receptor subtype). Researchers believe that binding at the receptor activates the trigeminal parasympathetic pathway, which leads to an increase of basal tear film also known as the protective tear film. This layer of tear film provides moisture to the eye and protection from external particles that may cause irritation, inflammation, and infection.
Clinical trial highlights
Tyrvaya was approved by FDA based on ONSET-1 (phase 2b, multicenter, randomized, double-masked, controlled) and ONSET-2 (phase 3, multicenter, randomized, double-masked, controlled) clinical trials. Inclusion criteria was the use of or desire to use an artificial tear substitute for dry eye disease within the 6 months prior to the first clinical visit for the trial. Patients who had undergone intraocular or extraocular surgery within the 3 months prior to their first clinical visit as well as patients who had undergone refractive surgery within 12 months prior to their first clinical visit were excluded from the trial. The primary outcome studied was the percentage of patients who achieved ≥10 mm in Schirmer’s Test Score (a test used to assess tear production) from baseline to day 28 of therapy. A statistically significant difference was ultimately found in participants in both groups who received the varenicline nasal spray when compared to participants who received placebo.
Adverse effects, contraindications
In clinical trials, the most common adverse effect was sneezing, which was experienced by about 82% of patients who received the varenicline nasal spray. Coughing, throat irritation, and nose irritation were also reported as adverse effects in over 5% of participants who received Tyrvaya.
There are currently no contraindications to Tyrvaya.
Patient counseling
As with all nasal sprays, discuss proper administration with the patient. Tyrvaya is packaged in 2 bottles comprising a 30-day supply. Each spray bottle delivers a 15-day supply and must initially be primed by pushing the sprayer 7 times into the air. The bottles should not be shaken prior to administration and should be stored at room temperature. Advise patients not to open both bottles at the same time; they should use one full bottle before using the second bottle. After administration, the patient should be counseled to wipe the nasal applicator with a clean tissue and replace the cap. If a dose is missed, the patient should wait until the next dose and administer the recommended one spray per nostril. The dose should not be doubled. ■