New cold sore treatments combat 100 million outbreaks in U.S. each year.

Key Points

They may go by the innocuous names of cold sores or fever blisters, but in reality those painful and unsightly eruptions outside the mouth – on the lips, chin, or cheeks, or in the nostrils – are predominantly caused by the highly contagious herpes simplex I (HSV1) virus (as opposed to canker sores inside the mouth, which are caused by allergic reactions or faulty immune systems).

Approximately 80 percent of all Americans are infected with HSV1 and approximately 20 percent to 40 percent of adults suffer from recurrent outbreaks of cold sores. About 100 million episodes of recurrent cold sores occur yearly in the United States alone. And currently there is no cure. Small wonder that pharmacy customers will be seeking help to treat their symptoms.

Recent arrivals

Also with ease of application in mind, Orajel has introduced the Orajel Medicated Cold Sore Brush, a soft-tip brush dispenser designed to apply directly to the cold sore. The medication contains a pain reliever, three moisturizing skin protectants, and a unique herbal complex to help speed healing and stop the pain and burning. The dispenser provides about 50 applications and is retail priced from $7.49 to $8.49.

Viroxyn (Quadex Pharmaceuticals) had been marketed through the professional dental market since receiving Food and Drug Administration (FDA) approval in 2003 and only recently became available to the retail OTC market. Triad Pharmaceuticals markets Viroxyn under various retailer private label brands as well as the Triad brand.

Viroxyn is a new pharmacological approach in which the unique applicator (which prevents cross-contamination) and the solvent drive the active ingredient (benzalkonium chloride) down to where the virus is. Jim McCarthy, Triad's technical director, said, "It basically disrupts the lipid coat of the virus and thus inactivates the virus." It also begins working immediately and thus is a single application. Viroxyn was launched in a duo-pack, with one treatment for the current cold sore and one for the next one - with the suggested retail price $14 to $15. More recently, some stores have begun offering a one-pack trial size, priced at 55 to 60 percent of the duo-pack.

McCarthy adds that pharmacists will want to remind patients to follow directions on the labeling. "For example, they should not put makeup on until the cold sore is done healing because there are ingredients in makeup that can deactivate the medicine's active ingredient." Similarly, certain ingredients in soft drinks and toothpaste will inactivate the active ingredient.

Natural care

The supplement L-lysine has been shown in clinical trials to reduce the frequency and severity of cold sore breakouts. L-lysine, an essential amino acid, inhibits normal replication of HSV, shortening the normal course and duration of the disease. Toronto clinician James Meschino has seen impressive results using the following dosages of L-lysine: "As a preventive, consider 1,000 to 2,000 milligrams (mg) per day (in two divided doses of 1,000 mg per dose). At the first sign of a cold sore breakout, up the daily dosage to 6,000 to 8,000 mg per day (divided doses of 2,000 mg per dose). It is best to take L-lysine on an empty stomach between meals." Meschino also has had clinical success in treating cold sores with other supplements and can be contacted through his Web site at http://www.renaisante.com/.

In the pipeline

Sweden's Medivir is developing Lipsovir, a combination of hydrocortisone and aciclovir, in a proprietary cream base. In phase III trials, treatment with Lipsovir prevented the development of cold sores in 42 percent of patients. In those patients who nevertheless developed a cold sore, the healing time and severity were significantly reduced. Approval applications are projected to be filed in the United States and Europe in October. Lipsovir is expected to initially be a prescription product in the United States, with a mix of OTC and prescription elsewhere on a country-by-country basis.

NanoBio Corp. has reported clear efficacy and safety in clinical trials of NB-001, an oil-in-water emulsion composed of nanometer-sized droplets that disrupts the outer lipid membrane of viruses without disrupting normal tissue. Because the product has an extremely safe profile, it has a potential for OTC. However, John Coffey, vice president of development, told Drug Topics, "That's going to be up to the FDA and the company that licenses the product. Most likely, initial launch will be prescription, but it will probably go to OTC pretty quickly." He added that it should be on the market in 2010.

DANA K. CASSELL is a freelance writer based in San Diego.