Targeted therapies improve care for Demodex blepharitis and OSD

(Image Credit: AdobeStock/OHishi_Foto)

A recent Ophthalmology Times Case-Based Roundtable^® tackled the topic of treating Demodex blepharitis and ocular surface disease (OSD) to maximize visual outcomes. Christopher E. Starr, MD, an associate professor of ophthalmology with Weill Cornell Medicine in New York, New York, described his pearls for treating affected patients.

Case 1

Addressing OSD preoperatively

Starr described the case of a 74-year-old woman being evaluated before cataract surgery. The patient reported red, crusty, and itchy eyelids and lashes, with symptoms worsening upon waking. She also experienced fluctuating vision that deteriorated throughout the day. She had a previous diagnosis of allergic conjunctivitis.

The diagnosis of Demodex blepharitis can be overlooked because physicians can misidentify the patient report as allergic conjunctivitis due to their description of itchy eyes. Starr pointed out that the location of the itchiness and the patient’s reaction to it may help identify the culprit. In the presence of Demodex blepharitis, the patient may run their fingernail along the eyelashes to relieve the itching, in contrast to rubbing the entire eye as with allergies. “Itchiness along the lashes is almost pathognomonic for Demodex blepharitis,” he said.

Severe OSD was another key factor in this case, which Starr treated aggressively before the patient’s planned cataract surgery. He described the topography as “irregularly irregular,” with variability between different time points and blinks, which is also pathognomonic for OSD. He reported discrepancies in keratometry and the axis of the astigmatism between the topographic and biometric values, making the planning to implant a toric IOL highly problematic. The cataract surgery was postponed in this case to address the severity of the OSD.

An important part of the ocular examination includes looking for rosacea, blink asymmetry, proptosis, and blink quality. Starr advised having the patient look downward for the best observation of the superior lashes to identify collarettes indicating Demodex blepharitis. Lifting the upper lid should display any corneal/conjunctival pathology. Pulling the upper lid facilitates assessment of lid laxity, and pushing on the meibomian glands can assess the expression of meibum.

Treatment and outcomes

This patient had Demodex blepharitis, low tear volume, and significant corneal staining that translated to significant OSD that will affect preoperative measurements and outcomes. Treatment included topical antibiotics because of the potential higher amount of load gram-positive bacteria present with the Demodex, which when untreated may increase the risk of endophthalmitis; topical steroids to treat inflammation; perfluorohexyloctane eyedrops for corneal damage; blepharoexfoliation to remove the biofilm and debride the collarettes; thermopulsation to treat the meibomian gland dysfunction (MGD); topical immunomodulation for inflammation; and lotilaner ophthalmic solution (Xdemvy; Tarsus Pharmaceuticals) twice daily for 6 weeks for the Demodex.

After 6 weeks, the collarettes and the gram-positive bacteria resolved, and the eyelids were not crusty, itchy, or red. The refractive measurements were all consistent, stable, and aligned perfectly, facilitating appropriate positioning of the toric lens. The topography was regular. The symptomatology decreased dramatically, and the corneal staining resolved.

Case 2:

Treating a nonsurgical patient

A 35-year-old woman described recurrent styes, an inability to wear contact lenses for a full day, a poor eyelid appearance, and difficulty with wearing eye makeup. She had been treated for rosacea with doxycycline and for acne with isotretinoin.

Examination showed normal osmolarity, no inflammation, MGD with poor expression and thick meibum (evaporative dry eye), lid margin pits and chalazia on both lids, meibomian gland attenuation, ocular/facial rosacea, low tear meniscus, normal osmolarity, inferior corneal staining, and anterior blepharitis with significant collarettes.

Treatment and outcome

Starr recommended standard therapy, including warm compresses, lid hygiene, careful makeup removal, and the use of preservative-free cosmetics safe for the eyes. He also recommended combined thermopulsation and microblepharoexfoliation therapy, along with considering intense pulsed light therapy as an initial step for facial rosacea, lid telangiectasias, and facial Demodex.

He continued the patient on a treatment regimen of oral doxycycline and ivermectin 1% cream and prescribed lotilaner eyedrops twice daily for 6 weeks. After 8 weeks of treatment, the patient reported feeling better, wearing contact lenses all day without discomfort, experiencing no new chalazia, and being able to wear mascara and eyeliner again. She also noted that her eyes and lids felt great, and her overall quality of life had improved.

Experience with lotilaner

Starr described a study that evaluated the long-term outcomes of 6 weeks of treatment with lotilaner, which has been available for a couple of years.¹ The study showed that a 6-week course of the drug worked well. “In almost 100% of patients, the collarettes were gone after 6 weeks,” he reported. He explained that he only occasionally prescribes the drug for a more extended period, as most patients see resolution of Demodex blepharitis within 6 weeks, with low recurrence rates.

A second study of the safety and efficacy of lotilaner compared with vehicle was performed in patients with Demodex blepharitis with MGD.² Demodex folliculorum is present in eyelashes and Demodex brevis can be present in the meibomian glands. The latter may also be a significant factor in the development of MGD.

Results of this study of a 6- to 8-week course of lotilaner showed that both the MGD secretion score and the number of glands yielding any liquid improved significantly compared with vehicle at days 43 and 85. “The lotilaner likely kills both Demodex folliculorum and brevis, which secondarily has a positive impact on meibomian gland secretions and function, resulting in improved MGD,” Starr said.

Christopher E. Starr, MD

E: cestarr@med.cornell.edu

Starr is an associate professor of ophthalmology with Weill Cornell Medicine in New York, New York. He is a consultant to Tarsus Pharmaceuticals.

References

1. Sadri E, Paauw JD, Ciolino JB, et al. Long-term outcomes of 6-week treatment of lotilaner ophthalmic solution, 0.25%, for Demodex blepharitis: a noninterventional extension study. Cornea. 2024;43(11):1368-1374. doi:10.1097/ICO.0000000000003484

2. Gaddie IB, Vollmer P, O’Dell L, Baba S, Dhamdhere K. Lotilaner ophthalmic solution, 0.25% for meibomian gland disease in patients with Demodex blepharitis. Poster presented at: 2024 American Academy of Optometry Annual Meeting; November 6-9, 2024; Indianapolis, Indiana.