The New Renaissance
BY BRUCE E. ONOFREY, OD, RPH
The first Renaissance represented a dramatic leap forward in culture, arts and science. Today
another renaissance is taking place, involving ocular allergic disease management. This disorder that is significant by its effect on millions of people and its cost in lost productivity, medication and exacerbation of pre-existing respiratory disorders like emphysema and asthma.
- The ophthalmic industry has:
- Better understanding of immune mechanisms
- "Multi-tasking" drugs
- Safer, more effective therapy
- Better patient counseling
Mechanisms. Mechanisms other than histamine produce more significant and debilitating late-phase inflammatory changes not typically associated with seasonal allergic disease. Eosinophil chemotactic factor and platelet activating factor attract these cells and lead to progressive increase in the local tissue response.
"Multi-tasking" drugs. In the last year there has been an explosion of effective, long-acting products developed as a result of the improved understanding of immune mechanisms. Several products work by blocking key parts of the immune cascade, resulting in improved drug efficacy.
Safer medications. The approval of loteprednol (Alrex) marked the first time that the FDA approved a steroid for allergic disease. These site-specific drugs represent a whole new approach to increasing drug efficacy and reducing adverse effects of ophthalmic medications.
Patient counseling. Better knowledge of immune mechanisms and new ways to treat translate into better informed doctors. Doctors can share new concepts and treatments with long-suffering patients.
Alcon's olopatadine (Patanol) started the revolution in allergy management as the first multi-purpose medication with a "user-friendly" profile. Twice daily dosing and antihistamine/mast cell stabilizing activity made it a sure favorite among doctors from day one. The only "perceived" problem was a price of over $50 per 5ml bottle.
Zaditor (ketotifen fumarate), the new offering from CIBA Pharmaceuticals, promises mast cell stabilization, antihistamine activity and inhibition of eosinophils. CIBA also claims a longer half-life than Patanol (12 vs. 8 hours). The greatest advantage is a 15-20 percent reduction in the price of the product compared to Patanol.
Allergan's recent release of topical nedocromil sodium 2% (Alocril) promises things not normally expected from a mast cell stabilizer. The most incredible claim is an onset of action of only 15 minutes. Company-supported literature claims that Alocril not only inhibits mast cells, but also affects other cellular components of the immune response (neutrophils, eosinophils and lymphocytes) and suggest that it possesses "broad spectrum" anti-inflammatory activity. What also makes Alocril unique is its bid dosing schedule. Other mast cell inhibitors must be dosed four to six times daily for efficacy.
Santen's pemirolast (Alomast) does not appear to bring anything new to the market. Its suggested dosing interval matches other existing mast cell inhibitors at four times daily.
Bausch and Lomb's loteprednol 0.2% (Alrex) has high receptor affinity and is metabolized rapidly in a single step. This results in high efficacy and almost non-existent classic steroid adverse effects (steroid glaucoma and cataract). This drug gives clinicians a relatively safe drug to manage those patients with acute disease that does not respond to more traditional anti-allergy therapies.
Dr. Onofrey, editor and author of various ophthalmic texts, practices in Albuquerque, N.M.