An oral drug approved for the treatment of pseudobulbar affections – involuntary outbursts of laughter or crying – in people with amyotrophic lateral sclerosis or multiple sclerosis is more often prescribed to treat those with Parkinson's disease or dementia, a study based on reports from databases on the health of the United States.
I study "Evaluation of the use of combined dextromethorphan and quinidine in patients with dementia or Parkinson's disease after approval by the US Food and Drug Administration for the influence of Pseudobulbar," Posted in JAMA Internal Medicine, he also noted a greater risk of falls and possible heart problems in these groups of older patients.
Nuedexta (dextromethorphan-quinidine), of Avanir Pharmaceuticals, was approved for the treatment of pseudobulbar disease (PBA) in patients with multiple sclerosis and multiple sclerosis by the FDA in 2010. PBA refers to sudden, uncontrollable and often inappropriate episodes. to cry or laugh.
The approval was based on the results of a phase 3 clinical trial (NCT00573443) conducted in people with ALS and MS who demonstrated that these explosions were reduced by about half among patients treated in the 12 weeks compared to those treated with placebo.
His initial label noted that Nuedexta was not known to be "safe or effective in other types of emotional lability that can commonly occur, for example, in Alzheimer's disease and other forms of dementia." But a 10-week phase 2 study (NCT01584440) found its use of lowered one- or two-point agitation scores in patients with probable Alzheimer's disease over 10 weeks compared to those treated with placebo.
Alzheimer's patients treated with dextromethorphan-quinidine also had higher rates of falls and infections of the urinary tract, but "generally well tolerated," according to a study published in 2015 reporting that trial. Prescribing information for Nuedexta was updated the same year to remove the initial warning statement.
The extrapolation of the efficacy and safety of a therapy for patients who have not been the focus of rigorous research is common but can be clinically challenging, particularly when there is little evidence to support the likely clinical benefit and security. Because Parkinson's and dementia sufferers can experience rapid and exaggerated mood changes, the researchers decided to examine prescription models for Nuedexta and changes in prescriptions and cost trends over time.
Since it has been shown that Nuedexta is commonly prescribed to patients with dementia and / or Parkinson's disease, as they may also experience rapid and exaggerated mood changes, the researchers looked at prescription patterns of the drug and how prescription and cost trends have changed over time.
They used data from two commercial insurance databases, Optum Clinformatics Data Mart and Truven Health MarketScan, to evaluate the number of prescriptions and total expenditure reported by the Centers for Medicare and Medicaid services. Data were collected on 12,858 patients subject to prescription from October 29, 2010 (Nuedexta approval date), until December 31, 2015 (the most recent data for the Truven database) and March 1, 2017.
Combining the results of both databases, the researchers found that only 8.4% of patients who prescribed Nuedexta had a diagnosis of MS and only 6.8% had one for ALS.
Rather, most patients who prescribed Nuedexta – 57.0% – were sick with Parkinson's or dementia. "Our results suggest that dextromethorphan-quinidine was primarily prescribed for patients with dementia and / or PD," the study noted.
Furthermore, 13.3% of the patients prescribed had a history of heart failure, which is a contraindication to therapy.
There was also an increase of over 15 times the number of patients who prescribed Nuedexta from 2011 to 2016, respectively from 3,296 to 50,402. Similarly, the study found that expenditure reported by Medicare and Medicaid services centers on Nuedexta increased from $ 3.9 million in 2011 to $ 200.4 million in 2016.
These results show that despite the fact that FDA's approval of Nuedexta for pseudobulbar influence was based on studies conducted in patients with ALS or MS, the drug appears to be primarily prescribed for elderly patients with dementia and / or Parkinson's disease.
"Current therapies to treat behavioral symptoms of dementia are largely ineffective, so doctors may want to prescribe dextromethorphan-quinidine to see if it helps their patients, despite the lack of experimental evidence on its effectiveness in this context," the researchers wrote. "However, the absence of data showing efficacy, together with the proven risks of falls and possible cardiac effects, challenges this strategy."
Similar to antipsychotics, Nuedexta is also prescribed to a larger and older patient population than its pre-approval study group, the researchers said. "[W]And he found that it is used in a population of about 15 years older than that included in the main pre-approval clinical study (mean age, 66.0 years versus 52.0 years). Age is one of the strongest risk factors among all drugs for adverse drug events. "
In light of these results, the researchers stressed that further attention should be paid to the training of physicians on the potential benefits and risks of this drug. They added that the FDA should monitor patient populations more closely using a drug after its approval and recommended further studies of Nuedexta in individuals with Parkinson's and dementia.