2001:The Year of Glaucoma
Our patients will benefit from these safer, more effective drugs.
By Jimmy Bartlett, O.D., F.A.A.O., Birmingham, Ala.
It's exciting to see new and improved medications to treat our patients who have ocular allergies and infections
(see "Allergy and Infection Update"), but it's equally gratifying to see the tremendous advances in the development of ocular hypotensive agents to treat glaucoma.
Several new glaucoma drugs were introduced in early 2001, and we're happy to add them to our Pocket-Sized Ophthalmic Drug Guide,
which you can request by calling Todd Galles, 707.256.1412, at Santen. Here's a brief rundown of these new drugs:
- Lumigan. Bimatoprost 0.03% from Allergan, Inc. is the first of a novel class of compounds called "prostamides." These compounds are believed to maintain aqueous humor dynamics and to help modulate intraocular pressure
Lumigan is a synthetic prostamide with powerful ocular hypotensive effects. When used just once daily, this medication can reduce IOP about 35%, and almost one-third of patients may experience a 40% or more reduction of IOP. This product does not require refrigeration.
- Rescula. Unoprostone isopropyl 0.15%, a docosanoid from Novartis Ophthalmics, is new in the United States but was introduced several years ago in Japan. Its ocular hypotensive effects are similar to those of betaxolol. Clinical studies have shown that unoprostone improves ocular blood flow to the retina, choroid and optic nerve tissues. This property suggests that the drug might be neuroprotective in patients who have primary open-angle glaucoma or normal tension glaucoma. However, we don't have enough data yet to support using this drug as a neuroprotectant. Unlike other drugs in the prostaglandin family, unoprostone must be dosed twice daily.
- Travatan. Travoprost 0.004% from Alcon is the newest prostaglandin analog approved for use in the United States. Travoprost is dosed once daily in the evening and yields ocular hypotensive effects comparable to those of latanoprost
Unlike latanoprost, however, travoprost doesn't require refrigeration before dispensing. Studies are underway to determine if travoprost is more effective than latanoprost in African-American patients.
And watch for the following drugs. They're FDA-approved and awaiting official launch:
- Alphagan P. This new drug from Allergan, Inc. contains the active ingredient brimonidine tartrate 0.15% and the preservative Purite in a 0.005% concentration.
An oxychloro-complex that breaks down to sodium chloride and water upon exposure to ultraviolet radiation, Purite is better tolerated than the more commonly used benzalkonium chloride and is less apt to cause
Studies comparing the ocular safety and efficacy of Alphagan P 0.15% with Alphagan 0.2% indicate that Alphagan P lowers IOP as well as Alphagan 0.2%.
As with Alphagan, the recommended dosage for Alphagan P is three times daily, although many practitioners will prescribe it only twice daily.
- Betaxon. Alcon's levobetaxolol HCl 0.5%, the levo-isomer of betaxolol, has the same systemic safety advantages of the parent compound, but is somewhat more effective than betaxolol in reducing
Levobetaxolol doesn't have the same ocular hypotensive effect as timolol or other nonselective beta-blockers.
Safer and more effective
Clearly, we can see that our glaucoma practices will change with the times as more effective and less toxic medications become available.
Long gone are the days when we had to use beta-blockers as first-line therapy for patients.
Now, we can offer our patients once- or twice-daily dosing with medications that are usually quite effective in reducing IOP --and these medications have more easily managed adverse-effect profiles.
Surely, our patients will be the ultimate beneficiaries of these advances in glaucoma.
Dr. Bartlett is interim chair at the University of Alabama at Birmingham (UAB) Department of Optometry. He's also a professor of optometry at UAB School of Optometry and is a professor of pharmacology at the UAB School of Medicine.
Allergy and Infection Update
During the last year or two, we've seen a number of important new anti-allergy drugs approved for ophthalmic use. One notable entry is Santen Inc.'s mast cell inhibitor, pemirolast potassium
(Alamast), which is commercially formulated as a 0.1% solution.
You can use pemirolast prophylactically like other mast cell inhibitors to reduce signs and symptoms of seasonal allergic conjunctivitis. It's been shown to be quite safe and virtually nontoxic to the cornea and conjunctival tissues when used long term. A typical dosage is 1 to 2 drops four times daily.
During the past year, a new fluoroquinolone was approved for the treatment of bacterial conjunctivitis. Levofloxacin 0.5%
(Quixin), also from Santen, Inc., may have advantages over existing quinolones because it's highly soluble and more effective against Streptococcus species. The recommended dosage is 1 to 2 drops every 2 hours while awake for the first 2 days and then every 4 hours while awake up to four times daily.
Optometric Management, Issue: June 2001