Chemical Leukoderma Associated with Methylphenidate Transdermal System: Data From the US Food and Drug Administration Adverse Event Reporting System.

OBJECTIVE: To identify and characterize cases of chemical leukoderma, an underrecognized adverse event, associated with the methylphenidate transdermal system (MTS) reported to the US Food and Drug Administration Adverse Event Reporting System (FAERS). STUDY DESIGN: We searched the Food and Drug Administration Adverse Event Reporting System for reports of chemical leukoderma associated with MTS, received by the Food and Drug Administration from April 6, 2006 to December 23, 2014. RESULTS: We identified 51 cases of chemical leukoderma reported with the use of MTS. The median age was 11 years; 43 cases reported leukoderma at or near the application site only, and 7 reported leukoderma at other parts of the body in addition to the application site; 1 case did not provide enough information to confirm the affected site. The time to onset ranged from 2 months to 4 years after the initiation of MTS. MTS was discontinued in 31 cases. Thirteen patients were prescribed treatment for repigmentation. Three cases reported continued spread of leukoderma after MTS was discontinued. Nineteen cases were diagnosed as vitiligo, including 5 cases reporting histologic features consistent with vitiligo. Leukoderma was persistent in all cases. The median follow-up interval after the discontinuation of MTS in 23 cases was 14 months. CONCLUSIONS: As outlined in recent changes to the prescribing information for MTS, health care professionals need to be aware of the potential risk of chemical leukoderma caused by MTS, especially given that chemical leukoderma is often misdiagnosed as idiopathic vitiligo. MTS should be discontinued at the earliest sign of pigment loss and other treatment options considered.

Liver injury associated with dimethyl fumarate in multiple sclerosis patients.

BACKGROUND: In pre-approval trials, there was an increased incidence of mild, transient elevations of liver aminotransferases in study subjects treated with dimethyl fumarate (DMF). OBJECTIVE/METHODS: To evaluate post-marketing cases of drug-induced liver injury associated with DMF. RESULTS: We identified 14 post-marketing cases of clinically significant liver injury. Findings included newly elevated serum liver aminotransferase and bilirubin levels that developed as early as a few days after the first dose of DMF. The pattern of liver injury was primarily hepatocellular. No cases resulted in liver failure. CONCLUSION: Health professionals should be alerted to possible serious liver injury in patients receiving DMF.

Adverse event detection using the FDA post-marketing drug safety surveillance system: Cardiotoxicity associated with loperamide abuse and misuse.

OBJECTIVE: The purpose of this investigation was to identify and characterize post-marketing reports of cardiotoxicity, including torsades de pointes (TdP), associated with loperamide use. METHODS: We searched the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) database for post-marketing reports of serious cardiac adverse events associated with loperamide use from December 28, 1976 (U.S. drug approval date), through December 14, 2015. We also conducted a Pubmed and Google Scholar search to identify additional published reports of cardiotoxicity associated with loperamide in the medical literature through February 11, 2016. RESULTS: Forty-eight cases of serious cardiac adverse events associated with loperamide use composed the case series. The most frequently reported cardiac adverse events were syncope (n = 24), cardiac arrest (n = 13), QT-interval prolongation (n = 13), ventricular tachycardia (n = 10), and TdP (n = 7). There were 10 cases that resulted in death. Of the 48 cases, the most commonly reported reasons for use can be characterized as drug abuse (n = 22) and diarrhea treatment (n = 17). More than one-half of the 48 cases were reported after 2010. Of the 22 drug abuse cases, the median daily dose was 250 mg (range 70 mg to 1600 mg) and events occurred as early as 6 hours after a dose and as long as 18 months after initiation of loperamide. Thirteen of the 22 cases reported using loperamide for euphoric or analgesic effects, and 9 reported use to prevent opioid withdrawal symptoms. CONCLUSION: The FAERS case reports provide evidence to suggest that high doses of loperamide are associated with TdP and other serious cardiac adverse events. The majority of cases in this series occurred in the setting of drug abuse for the purpose of preventing opioid withdrawal or to produce euphoric effects. It is important for both clinicians and patients to be aware of this potential risk, because prompt therapy and discontinuation of the offending agent are often essential to management and prevention of loperamide-induced cardiac arrhythmias.

Vilazodone: clinical basis for the US Food and Drug Administration's approval of a new antidepressant.

OBJECTIVE: Vilazodone was recently approved by the US Food and Drug Administration (FDA) for the treatment of major depressive disorder (MDD). The purpose of this review is to summarize the FDA's approach to its review of the clinical pharmacology and the clinical efficacy and safety data for this new drug application, important issues in its decision-making, and its conclusions. DATA SOURCES: The data sources for this review were the original raw data sets for all clinical trials included in the development program for vilazodone, as well as the sponsor's original analyses of these data. STUDY SELECTION: Data were available from 24 human trials involving vilazodone, and included a total of 2,898 human subjects exposed to 1 or more doses of this drug. DATA EXTRACTION: The FDA had access to original raw data sets for these trials. RESULTS: Vilazodone is effective in treating MDD at a dose of 40 mg/d, but it needs to be incrementally adjusted to this dose to minimize gastrointestinal symptoms. It needs to be taken with food to ensure adequate plasma concentrations. Vilazodone's profile of adverse events is similar to that seen with selective serotonin reuptake inhibitors. No dose adjustment is needed based on age, gender, or renal or hepatic impairment. It is recommended that the vilazodone dose be reduced to 20 mg when it is taken with strong cytochrome P450 (CYP) 3A4 inhibitors, eg, ketoconazole. Vilazodone is not expected to have important effects on the clearance of other drugs that are cytochrome P450 substrates. CONCLUSIONS: Vilazodone is a new treatment for MDD, but it is unknown whether it has any advantages compared to other drugs in the antidepressant class.