New Treatment for Meibomian Gland Dysfunction
New Treatment for Meibomian Gland Dysfunction
Eric D. Donnenfeld, MD, FACS
A new medication and treatment algorithm promise greater efficacy for the treatment of meibomian gland dysfunction.
Meibomian gland dysfunction (MGD), also known as posterior blepharitis, is one of the most common physical findings in primary eyecare patients. MGD is important to treat for several reasons. While MGD may not be sight threatening, it undermines patients’ quality of life enough that they often come to us for relief. Second, the abnormal lipids produced by MGD patients have a negative effect on the quality of the tear film, which produces both discomfort and visual acuity problems (Figure 1). Third, MGD can lead to chalazia, which can be painful and unsightly for the patient. MGD is also very highly associated with infections of the lid margins, so it may contribute to bacterial growth in the lids, which can increase the risk of infection following any kind of ocular surgery. Lastly, for so many of our patients, it can make wearing contact lenses very difficult.
Providers have historically considered MGD one of the most difficult diseases to treat because we have lacked a simple, effective therapy. The challenge with “mechanical” therapies (cleansing, hot compresses, massage) is adherence; the challenge with topical antibiotic drops and ointments is efficacy—they do not penetrate the lid margin well, and most lack the needed antiinflammatory effect. While more effective, oral tetracyclines often have unpleasant gastrointestinal side effects.
A New Approach
All this may be about to change, however. The topical preparation of the macrolide antibiotic azithromycin (AzaSite®; Inspire Pharmaceuticals) in a mucoadhesive vehicle (DuraSite®) promises us an agent that is easy to administer and truly effective. Unlike fluoroquinolones, macrolide antibiotics have antiinflammatory as well as antibacterial properties.
In addition, the vehicle in the new azithromycin preparation is mucoadhesive that adheres the antibiotic to the lid margins long enough for it to penetrate tissue. Azithromycin itself has high affinity for tissue and tends to reside there for long periods, offering a reservoir of drug for a lasting effect. Research in rabbit eyes shows that AzaSite can achieve tissue levels very substantially higher than can be achieved with any of our other ocular antibiotics.
Like the tetracyclines, azithromycin has antiinflammatory effects that are independent of its antibiotic effect. But, unlike the tetracyclines, which must be taken orally, we can now give azithromycin topically, so that there are no unpleasant systemic side effects. In addition, properties of both the drug and its vehicle make it possible to achieve and maintain effective tissue concentrations, even when the drug is taken just once a day. In fact, the tissue concentrations when azithromycin is given topically are such that effective levels are maintained for days or weeks after the drug is stopped.
Currently, AzaSite is approved only for the treatment of conjunctivitis, so its use for MGD is off-label. However, we have been using it to treat MGD very successfully in our practice and in open-label studies, and we’re initiating a double-masked controlled trial.
A New Regimen
We currently have patients take topical azithromycin as an integral part of a comprehensive lid disease treatment regimen. This includes lid cleansing with a commercial lid cleanser followed by hyperthermia (warm compresses—as warm as the patient can tolerate—for 3 to 5 minutes). The azithromycin drop is then applied to the lid margin and the lid massaged for about 10 seconds.
This regimen is performed twice a day (morning and evening) for 2 days, and then once a day in the evening for 28 days. After one month of treatment, azithromycin can be used on a month-on/month-off basis to control the inflammation. The cleansing, hyperthermia, and massage routine is continued as long as the patient is symptomatic.
Topical azithromycin plus lid hygiene comprises our first-line therapy. If additional therapy is needed, an oral tetracycline (minocycline or doxyclycline) can be added. If additional antiinflammatory effect is needed, topical cylcosporine (Restasis®; Allergan) and/or a topical corticosteroid can be added.
THE BOTTOM LINE
MGD affects many of our patients, and treatment options traditionally have been notorious for low efficacy and poor adherence. While the treatment still includes mechanical measures (lid cleansing, hyperthermia, and massage), the new topical azithromycin preparation promises to greatly improve our ability to help patients with this very unpleasant, chronic condition.
Eric D. Donnenfeld, MD, FACS, is a founding partner of ophthalmic consultants of Long Island and Connecticut and a clinical professor of ophthalmology at New York University Medical Center. Dr. Donnenfeld is a consultant for Allergan, AMO, Alcon, Bausch & Lomb, Inspire Pharmaceuticals, and InSite Vision. He received assistance with this article from medical writer Mary Gabb, MS.
FIGURE 1A foamy tear film may be seen in MGD, a consequence of the saponification of tear lipids.