CVS Caremark study: More education needed on genetic testing in prescribing antiplatelet drugs
WOONSOCKET, R.I. — A new study conducted by researchers at CVS Caremark and Brigham and Women’s Hospital explored the impact of genetic testing on prescribing patterns for cardiovascular therapy and found that there is an opportunity to improve upon the information physicians and patients receive on the evolving body of evidence for pharmacogenomics.
The study, published in the November issue of the American Heart Association journal Circulation: Cardiovascular Quality and Outcomes, found that only 1-out-of-5 patients who tested as poor metabolizers of the blood thinner clopidogrel had their antiplatelet therapy changed as recommended by the FDA. In addition, the study found that prescribers declined genetic testing in 25% of cases evaluated, while less than 10% of patients who were directly offered the genetic evaluation declined testing. The researchers concluded that the prescribing patterns noted in the study likely reflect the unclear impact and physician uncertainty regarding the evidence for pharmacogenomics.
"We’re entering an age when we can begin to create tailored treatment regimens for individual patients, but a genetic test is only valuable when providers and their patients can understand and act on the results," Troyen A. Brennan, EVP and chief medical officer of CVS Caremark and a study co-author, said. "This research shows there is an opportunity to improve upon the information doctors and patients receive on this evolving topic so that they can make the best treatment decisions."
The study examined prescribing patterns for patients with recent acute coronary syndrome or percutaneous coronary intervention who were prescribed the antiplatelet medication clopidogrel. While clopidogrel has been shown to reduce the risk of major adverse cardiovascular events for these patients, there is significant variability in how individual patients respond to the drug. In fact, patients who are poor metabolizers of clopidogrel may have reduced therapeutic benefit and a higher risk of adverse cardiovascular events. The FDA has advised avoiding the use of clopidogrel in patients who are poor metabolizers and recently modified the boxed warning to advise health care professionals to consider the use of other antiplatelet medications or alternative dosing strategies for poor metabolizers.
Health care providers were offered access to a genetic test as part of the patient’s health benefit to identify the patient’s ability to metabolize clopidogrel. Nearly 500 patients completed the test, with approximately one-third of patients identified as being poor drug metabolizers. While the patients who underwent genetic testing were significantly more likely to have their antiplatelet regimen changed as compared with patients who did not undergo testing, only 20.5% of patients identified as being poor metabolizers had their antiplatelet therapy intensified or changed to another drug.
"In this study, about half of the providers that were contacted about the availability of a genetic testing benefit did not respond at all, and among those who did decide to use the test, the vast majority of patients identified as poor metabolizers did not have a change in therapy despite FDA warnings suggesting that they should," added Niteesh K. Choudhry, associate physician, Division of Pharmacoepidemiology and Pharmacoeconomics, Brigham and Women’s Hospital, associate professor, Harvard Medical School and the study’s senior investigator. "While there is significant uncertainty about how clinician’s should respond to the results of genetic testing for antiplatelet drugs, this study clearly shows that patients and their doctors need more guidance and education about how best to apply these results to improve patient outcomes."
Mast Therapeutics gets orphan drug designation for experimental acute limb ischemia drug
SAN DIEGO — The Food and Drug Administration has given special designation to a drug under development by Mast Therapeutics for a rare disease that restricts the flow of blood to the limbs.
Mast announced Wednesday that the FDA had granted its drug, MST-188, orphan drug designation as a treatment for acute limb ischemia. The FDA grants the designation to treatments for diseases that affect 200,000 or fewer people. Acute limb ischemia results from embolism or thrombosis and is estimated to affect 14 out of every 100,000 people in the United States each year, according to a 1999 study.
"This designation represents further progress in our development of MST-188 as an adjunct therapy for life-threatening conditions treated with existing thrombolytic agents, such as [tissue plasminogen activator]," Mast CEO Brian Culley said. "As we previously reported, we are on track to initiate a phase-2, clinical proof-of-concept study in acute limb ischemia in early 2014."
Research: Patients using Walgreens’ HIV-specialized pharmacies more adherent to their medications
DEERFIELD, Ill. — Walgreens recently presented research from two retrospective cohort studies exploring HIV and comorbid medication adherence at HIV-specialized pharmacies and the implications for HIV patients with serious mental illness. The research, presented at the Cell-Lancet conference, "What Will it Take to Achieve an AIDS-free World?," in San Francisco Nov. 3-5, demonstrates that adherence to therapeutic treatments for HIV and associated comorbidities, such as serious mental illness, was significantly higher for patients using Walgreens HIV-specialized pharmacies than for patients using other Walgreens retail pharmacies.
“Medication adherence is vital to maintaining optimal health for patients with the HIV virus. Poor medication adherence can lead to treatment failure, resistance to therapy and increased mortality and is one of the greatest and most costly barriers in treating illness today,” Janeen DuChane, senior director of clinical outcomes and analytics, Walgreens stated. “By developing specialized patient support programs, we can improve adherence for HIV patients, better serve HIV populations and reduce medical costs.”
In examining the differences in medication adherence for patients using Walgreens HIV-specialized pharmacies and those using other Walgreens retail pharmacies, researchers confirmed that HIV patients utilizing the specialized pharmacies were more adherent to their anti-retroviral and comorbid therapies. The study found that the mean proportion of days covered for patients using Walgreens HIV-specialized pharmacies was significantly higher than for patients using other Walgreens retail pharmacies.
For patients taking angiotensin converting enzyme or angiotensin receptor blocker (drugs used to treat hypertension), Walgreens HIV-specialized pharmacy users had a significantly higher mean proportion of days covered of 82.6% compared with 79.6% in patients using other Walgreens retail pharmacies.
Among patients taking statins (drugs used to treat high cholesterol), Walgreens HIV-specialized pharmacy users also had a higher mean proportion of days covered of 83.7% than those using other Walgreens retail pharmacies (81.3%).
In a separate study, Walgreens researchers conducted a retrospective data analysis of HIV patients with serious mental illness, a group that often experience challenges associated with the willingness and ability to take medication as prescribed which can contribute to a two-fold increase in hospitalization costs. Nearly 30% of HIV patients assessed had an indication of serious mental illness comorbidity and demonstrated increased medication adherence2 when utilizing a Walgreens HIV-specialized pharmacy. Among HIV patients with serious mental illness who exclusively used HIV-specialized pharmacies, 32.7% were adherent to their anti-retroviral therapy versus 19.4% for HIV patients with serious mental illness using other Walgreens retail pharmacies.
"Both studies validate the benefit of patient medication adherence associated with HIV-specialized pharmacies and underscore Walgreens commitment to be a part of the solution to end AIDS," Walgreens stated in a release. "Walgreens award-winning HIV-specialized pharmacies provide education, counseling, testing and treatment through its more than 2,000 HIV-trained pharmacists at more than 700 locations."