Public Citizen Criticizes FDA For Rejecting Blood Pressure Drugs Black Box Warnings

A prominent consumer watchdog group is taking the FDA to task for refusing to require stronger label warnings about the risks associated with the combined use of a number of popular hypertension drugs, like Benicar and Aliskiren. 

On April 3 the FDA notified Public Citizen that it was rejecting a 2012 petition to add black box warnings to hypertension drugs such as angiotensin-converting-enzyme (ACE) inhibitors, angiotensin-receptor blockers (ARB) and Aliskiren, alerting doctors and patients not to use the drugs in combination.

All of the drugs affect the body’s renin-angiotensin system (RAS), and the FDA acknowledges that chronic activation of the RAS can lead to constriction of blood cells, vascular injury, inflammation and other health risks. However, the agency said the drugs carry sufficient warnings.

“As with any drug therapy, pharmacologic inhibition of the RAS has certain risks,” the FDA rejection letter (PDF) states. “Consequently, the labeling for every ACE inhibitor, ARB, and aliskiren drug product describes these adverse events and recommends periodic patient monitoring.”

Public Citizen officials say those warnings are not enough.

“Public Citizen strongly believes that only a black box warning can adequately alert the remaining physicians prescribing combination therapy to its dangers,” Dr. Sammy Almashat, a researcher with Public Citizen’s Health Research Group, said in a press release. “Burying such a warning deep within the medications’ physician labels, as the FDA is currently doing, guarantees that hundreds of thousands of patients will continue to unknowingly be exposed to these preventable harms.”

To date, the FDA only contraindicates against the use of aliskiren with either an ACE inhibitor or an ARB in diabetics, Public Citizen officials note. They also note that two ACE inhibitors, captopril and fosinopril, lack even this warning. Public Citizen officials say the FDA needs to also make the same contraindication against combining ACE inhibitors and ARBs.

A black box label warning is the strongest label warning the FDA can require a drug to carry.

ACE inhibitors and ARBs, like Benicar, losartan and lisinopril, are blood pressure medications that are often prescribed to help with kidney disease triggered by diabetes. They help lower blood pressure and reduce the amount of protein in the urine, often a sign of kidney damage.

A study published in November 2013 in the New England Journal of Medicine found that combining the drugs does not help reduce end-stage kidney disease and actually can cause additional harm to kidneys. The study was halted in 2012 due to concerns about the frequency and degree of adverse side effects affecting the study’s 1,500 participants.

While some patients saw a slight decrease in the progression of the disease, the change was not significant. Instead, a significant increase in serious side effects was seen.

More study participants required hospitalizations, additional kidney treatments and symptoms of severe kidney injury. The combination group also faced an increased the risk of hyperkalemia, elevated levels of potassium in the blood. At extremely high levels, hyperkalemia can cause cardiac arrest and death.

Benicar Sprue-Like Enteropathy

The findings come as the makers of Benicar, one of the best-selling ARBs, face criticism over failure to adequately warn about the risk of intestinal side effects associated with the drug, including chronic diarrhea and other symptoms of a condition known as sprue-like enteropathy.

Benicar (olmesartan medoxomil) is part of a family of Daiichi Sankyo hypertension drugs, which also includes Benicar HCT, Azor and Tribenzor. All of the blood pressure drugs include the active ingredient olmesartan, which has been linked to the development sprue-like enteropathy.

As a result of the lack of warnings provided by the drug makers, many users have repeatedly been hospitalized with severe diarrhea, as doctors were unaware that the symptoms may be caused by their blood pressure medication. The Benicar problems have often been misdiagnosed as Celiac disease or unclassified sprue, resulting in continued use of the medication, which could leave users with long-term intestinal damage.

Although the diarrhea symptoms associated with sprue-like enteropathy typically resolve when the medication is no longer used, the problems can cause permanent damage to the intestines, known as villous atrophy from Benicar.

Daiich Sankyo and Forest Laboratories face a growing number of Benicar lawsuits by patients who say the companies failed to provide adequate warning of the risk of sprue-like enteropathy.