• Generic Drug Use Shown to Improve Medication Adherence in People with Glaucoma

    Researchers recommend ophthalmologists consider switching nonadherent patients to unbranded options

    SAN FRANCISCO – In the first study to examine the impact of a reduction in glaucoma medication copay on patient adherence, researchers in Michigan have found a potential solution to one of the biggest obstacles facing American ophthalmologists in the fight against glaucoma-related blindness.

    Despite the availability of effective treatments, more than half of glaucoma patients do not take their medications as prescribed.[1] A study published online by Ophthalmology, the journal of the American Academy of Ophthalmology, reveals that one way to solve this problem may be switching nonadherent patients to generic drugs. Researchers found this improved medication adherence by 25 percent or greater in a group of patients who had previously struggled to consistently take their medications.

    The standard treatment for open-angle glaucoma – the most common form of the disease in the United States – is a class of medications called prostaglandin analogues (PGAs), which are eye drops that lower intraocular pressure. While PGAs are highly effective, the brand name versions are often more costly than other classes of glaucoma drugs, and researchers have suspected that the high cost may be an important reason why so many patients do not take their medication as prescribed. In March 2011, the first and only generic PGA, latanoprost, became available in the United States. At the time, it was priced to save a typical patient approximately $1,300 a year when compared to buying brand name products.

    To determine how the generic drug’s availability may have impacted adherence, researchers from the University of Michigan Medical School and University of Michigan College of Pharmacy examined claims data from 8,427 glaucoma patients for the 18 months before and after latanoprost became available. All subjects were taking name brand PGAs prior to the availability of generic latanoprost, but after the generic drug’s introduction, some stayed on the name-brand medications while others shifted to the generic drug.

    The researchers found that among the patients with suboptimal adherence, those who switched to generic latanoprost once it became available generally experienced a 25 percent or greater improvement in adherence. In contrast, there was no significant change among those who continued taking the name-brand drugs.

    Other factors associated with adherence improvement included higher prescription copays prior to the introduction of generic latanoprost or lower prescription copays after the introduction of generic latanoprost. The researchers speculate that the lower cost of generic latanoprost may be the primary reason for the improvement. They also found improved adherence among African-American patients who switched to generic drugs, and noted that African-Americans tend to have more severe glaucoma compared to other ethnicities and therefore have a more complex medication regimen, which affects both cost and adherence.

    “As a glaucoma specialist, I know that some of my patients require three or four different classes of medications. Individuals’ out-of-pocket costs for glaucoma medications can exceed $100 per month, and the high drug cost may deter patients on a tight budget from consistently buying and taking their medications as prescribed,” said Joshua D. Stein, M.D., lead author and associate professor of ophthalmology and visual sciences at the University of Michigan Kellogg Eye Center. “It’s reassuring to find that switching patients to more affordable, generic drugs could be an effective solution for a subgroup of patients who have difficulty with adherence.”

    Dr. Stein added that the findings may have applications beyond glaucoma to other chronic conditions – such as high blood pressure, diabetes and high cholesterol – for which patients similarly struggle with medication adherence.

    The investigators recommend that ophthalmologists consider switching to generic drugs when available for patients who struggle with adherence. Similarly, they advise patients with glaucoma to talk with their ophthalmologist about whether any of their prescribed medications are available as generic products and if they could be switched to such products when applicable.

    Glaucoma is a leading cause of irreversible blindness worldwide, affecting more than 2.7 million Americans aged 40 and older and 64.3 million people globally.[2],[3] The American Academy of Ophthalmology recommends that all adults have a comprehensive eye exam by age 40 – the time when early signs of age-related eye disease and changes in vision may start to happen. Based on the results of this exam, the ophthalmologist – a physician and surgeon who treats eye diseases and conditions – will advise when follow up exams are necessary.

    About the American Academy of Ophthalmology

    The American Academy of Ophthalmology, headquartered in San Francisco, is the world's largest association of eye physicians and surgeons, serving more than 32,000 members worldwide. The Academy's mission is to advance the lifelong learning and professional interests of ophthalmologists to ensure that the public can obtain the best possible eye care. For more information, visit www.aao.org. 

    The Academy is also a leading provider of eye care information to the public. The Academy's EyeSmart® program educates the public about the importance of eye health and empowers them to preserve healthy vision. EyeSmart provides the most trusted and medically accurate information about eye diseases, conditions and injuries. OjosSanos™ is the Spanish-language version of the program. Visit EyeSmart or OjosSanos to learn more.

    About Ophthalmology

    Ophthalmology, the official journal of the American Academy of Ophthalmology, publishes original, peer-reviewed, clinically-applicable research. Topics include the results of clinical trials, new diagnostic and surgical techniques, treatment methods, technology assessments, translational science reviews and editorials. For more information, visit www.aaojournal.org.

    [1] http://www.ncbi.nlm.nih.gov/pubmed/19038625

    [2] https://www.nei.nih.gov/eyedata/glaucoma

    [3] http://www.ncbi.nlm.nih.gov/pubmed/24974815