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Research Briefs July 2017

Study: Avastin and Eylea Provide Similar Improvement in Visual Acuity

A head-to-head comparison of two drugs widely used for macular edema due to central retinal vein occlusion—bevacizumab (Avastin, Genentech) and aflibercept (Eylea, Regeneron)—found that both drugs improved visual acuity similarly. But Eylea does it for $1,850 per dose versus Avastin’s $60 per dose.

In the study, National Eye Institute (NEI) researchers randomly assigned 362 patients to aflibercept or bevacizumab by eye injection every four weeks for six months. At six months, the researchers assessed visual acuity, retinal thickness, and side effects.

On average, visual acuity improved about four lines on an eye chart, more than doubling the ability to resolve fine detail, said Frederick Ferris, MD, Director of the Division of Epidemiology and Clinical Applications at NEI. “For some patients it restores their ability to drive.”

Both drugs prevent the release of vascular endothelial growth factor, which causes swelling. The researchers found that macular edema declined significantly in both groups. The rates of adverse events, such as elevated intraocular pressure, were low and similar in both groups.

Retinal vein occlusion is associated with diabetes and hypertension, and affects more than 16 million adults worldwide.

Source: National Institutes of Health, May 2017

Prescribing Patterns Shift After Institutions Restrict “Detailing”

In the last decade, some medical institutions have been trying to halt the practice of “detailing”—pharmaceutical representatives promoting medications during sales visits to physicians. A National Institutes of Health (NIH) study is one of the first to document the effect of such restrictions. The researchers compared prescribing between 2006 and 2012 at 19 academic medical centers (AMCs) that instituted policies restricting detailing.

The study compared prescribing by 2,126 physicians at AMCs with prescribing by 24,593 physicians from a pharmacy benefits database. The analysis covered 16.1 million prescriptions in eight major drug classes: lipid lowering, gastroesophageal reflux disease, diabetes, hypertension, sleep, attention-deficit/hyperactivity disorder, depression, and antipsychosis.

At the centers with restrictions, physicians prescribed fewer promoted drugs and more nonpromoted drugs in the same drug classes. The mean market share of detailed drugs (across all the drug classes) in AMCs before the policy changes was 19.3%. Over the study period, the market share of detailed drugs prescribed by AMC physicians declined by 1.67 percentage points, an 8.7% decrease relative to the prechange level. The comparison group of physicians saw a slight decline over the same time period. While the drop was “modest,” NIH notes, proportionally small changes can represent thousands of prescriptions. The market share of nondetailed drugs increased by a relative 5.6%.

The changes were statistically significant for six of the eight drug classes and for all drugs in the aggregate. The magnitude of changes differed across AMCs, the researchers found. The decline was greatest at centers with the most stringent policies, such as bans on salespeople in patient care areas. In eight of 11 AMCs with more stringent policies, the changes in prescribing were significant, compared with only one of eight AMCs with more limited measures.

Source: NIH, May 2017

Genetic Information May Hold Key To Multiple-Substance Addiction

The Million Veteran Program (MVP) is now the largest genomic database in the world, with more than 550,000 U.S. veterans enrolled. Researchers have been mining the data for a variety of studies, including those to examine the genetic risk factors for chronic use of alcohol, tobacco, and opioids.

Most people who smoke or use drugs also drink alcohol, and changes in one behavior are likely to be associated with changes in the others, according to researchers from the Veterans Affairs (VA) Connecticut Healthcare System and Corporal Michael J. Crescenz VA Medical Center. That likelihood suggests a shared genetic risk for multiple-substance use, but to date, studies on the subject have been limited by the small size of the available samples, the researchers say. The MVP has changed that, providing a unique opportunity to analyze massive amounts of longitudinal data to discover potential genetic links.

The answers may also provide opportunities for treatment and prevention. For example, it may be possible to reduce the use of multiple harmful substances simultaneously with one or more medications.

The first target in this “ambitious effort,” the researchers say, is heavy drinking. They’re using data from the Veterans Aging Cohort Study and from the AUDIT-C, a self-report questionnaire given annually to veterans, which quantifies recent drinking. The researchers plan to validate their initial findings, already published, and then combine that information with the genotype information from the MVP to identify novel genetic predictors of heavy drinking.

The researchers have begun to use a similar approach to study chronic opioid use and smoking. Ultimately, they plan to integrate all of the findings to yield genetic profiles for multiple-substance use.

Source: Department of Veterans Affairs, May 2017

Metastasized Renal Cell Cancer In Remission With Sunitinib

Sunitinib (Sutent, Pfizer), a multi-tyrosine kinase inhibitor approved in 2006, has been shown to significantly prolong progression-free survival and overall survival in patients with metastatic renal cell cancer (RCC). But while some patients with metastasized RCC have reportedly achieved complete remission with sunitinib, clinical and pathological remission has seldom been described in reports, according to researchers from Jinan University in Guangzhou, China. They discuss a patient whose colonic metastasis of RCC resolved with microwave ablation and sunitinib.

The patient, who was diagnosed with RCC, underwent a right radical nephrectomy. A pathology report indicated clear-cell carcinoma of the kidney. Three years later, she presented with recurrent upper abdominal pain and was referred for treatment to the authors’ hospital. An ultrasound scan revealed cholecystitis and gall-bladder stones. During exploratory laparotomy, surgeons found a hepatic flexure colonic mass “firmly adhering” to the surrounding tissue; it perforated the intestine and could not be radically resected. The surgeons performed an ileostomy. During a follow-up, they found the cancer had spread to the liver. Metastasectomy was not possible, so her doctors chose microwave ablation. (They note that there is currently little experience with microwave ablation in the treatment of liver metastasis of RCC.)

The patient was also started on sunitinib at 50 mg per day on a schedule of four weeks of therapy followed by two weeks off therapy. A follow-up computerized tomography (CT) scan showed the treatment was shrinking the mass in the colon. Positron emission tomography–CT imaging showed no local signs of relapse. Three years after the microwave ablation, she underwent ileostomy reversal, hysterectomy, right hemicolectomy, and partial ileostomy. But all pathological results were benign.

In about 25% of patients, RCC metastasizes postoperatively—usually to the lungs and liver, the clinicians say. Colonic metastases are rare. On the basis of the patient’s clinical features, imaging data, and pathology results, they concluded that sunitinib, with microwave ablation, can prevent unresectable hepatic metastases of RCC from evolving, and sunitinib alone can achieve clinical and pathological remission of colonic metastases of RCC.

Source: Urology Case Reports, May 2017

Long-Term Effects of Concussive TBI

What are the long-term clinical effects of wartime traumatic brain injuries (TBIs)? Most are mild, but in general all are incompletely described, say researchers from the University of Washington in Seattle and Washington University in St. Louis. However, their own study found that service members with even mild concussive TBIs often “experienced evolution, not resolution” of symptoms.

The researchers compared the results of one-year and five-year clinical evaluations of 50 active-duty U.S. military personnel who had acute to subacute concussive blast injuries and 44 deployed but uninjured service members. The evaluations included neurobehavioral and neuropsychological performance and mental health burden.

At five years, global disability, satisfaction with life, neurobehavioral symptom severity, psychiatric symptom severity, and sleep impairment were significantly worse in patients with concussive blast TBIs. Of the patients with concussive blast TBIs, 36 (72%) showed a decline, compared with only five of the combat-deployed group (11%). The researchers also found symptoms of posttraumatic stress disorder and depression worsened in the concussive TBI patients. Performance on cognitive measures was no different between the two groups. A combination of factors, including neurobehavioral symptom severity, walking ability, and verbal fluency at one year after injury, was highly predictive of poor outcomes five years later.

“This is one of the first studies to connect the dots from injury to longer-term outcomes, and it shows that even mild concussions can lead to long-term impairment and continued decline in satisfaction with life,” said lead author Christine MacDonald, PhD. “Most physicians believe that patients will stabilize six to 12 months postinjury, but this study challenges that.”

The researchers also found that, while 80% of service members with concussions had sought mental health treatment, only 19% reported that those programs were helpful. The findings advocate for new treatment strategies, the researchers say, to “combat the long-term and extremely costly effect” of these wartime injuries.

Source: National Institutes of Health, May 2017

HCV Cases Have Been Underreported, CDC Says

The number of new hepatitis C virus (HCV) infections has tripled in just five years to a 15-year high, but the true scale is only now being revealed, according to the Centers for Disease Control and Prevention (CDC).

Limited surveillance resources have led to underreporting, the CDC says: The annual number of HCV cases reported doesn’t reflect the reality of the epidemic. Although 850 cases were reported in 2010 and 2,436 cases in 2015, the CDC estimates 34,000 actual new infections in 2015.

About three-quarters of the 3.5 million Americans with HCV are “baby-boomers” born between 1945 and 1965. They’re six times more likely to be infected with HCV and are at greater risk of death due to HCV. But HCV infections are spreading most rapidly among young adults 20–29 years of age, the CDC says, primarily because of injection-drug use associated with opioids.

Because of that dual threat of virus spread and the opioid epidemic, strategies recommended by the Department of Health and Human Services include using comprehensive syringe service programs (SSPs). One CDC study found that 80% of young people with HCV live more than 10 miles from an SSP. Another study found only three states have laws that support full access to SSPs, HCV-related treatment, and preventive services for people who inject drugs.

Source: CDC, May 2017