Dr. Robert Nelson filed the following expert witness report in the case of Swicegood v. Pliva. In it, he suggests that the manufacturers of Metoclopramide (the generic form of Reglan) have not lived up to their duty to sell a safe product:
There was an understanding by the FDA in the early 1980s that MCP, a dopaminergic agent, had the potential for TD given LT exposure. Initially its use was limited to inpatients and severe DG. However, it was eventually approved for up to 12 weeks treatment of GERD.
The reports of MCP-TD presented in Section X of this report all attribute TD as a consequences of off-label long-term use. Grimes (1982b) and Wiholm (1984) were the first to analyze the signal and publish the problem.
Miller and Jankovic (1989) found the TD emerges, on average, 12 months of exposure and that treatment was continued for an average of 6 months AFTER involuntary movements had started. Sewell (1992a) reviewed the reports in the literature and found 67 cases of MCP-TD with 20 months duration of exposure.
Stewart (1992b) analyzed “inappropriate” long-term use of MCP in the elderly. This descriptive study identified 34 exposed to MCP from 4515 (2898 females; 1617 males) patients who participated in a health screening research program in Florida, 11 (32.4%) were long-term users. The study was initiated because two patients presented to the University hospital with MCP-induced TD within the prior year. Both had taken MCP for longer than 8 years for GERD. Only three of the 34 participants had diabetes mellitus (DM), so GERD or heart-burn-like ailments and not DG was their likely treatment diagnosis. This small study signaled that LT-MCP was a substantial component of MCP use in the elderly.
These published cases and the studies of Stewart, Ganzini, and Sewell made the problem of long-term off-label use visible and highlighted its unique consequences.
To assess risk factors for TD in MCP exposed persons, Schaffer et.al. (2004) reviewed the reports in the FDA Adverse Reaction Reporting System (AERS) through June 2003. They also used the IMS Health data to evaluate MCP prescribing patterns before and after the withdrawal of cisapride from the US marketplace. They extracted a case-series of 87 reports from AERS with TD as the adverse outcome and MCP as an exposure. Each case was re-evaluation for validity of both exposure and outcome. Data regarding prescription utilization (via National Prescription Audit, NPA) and demographics of patients (National Disease & Therapeutic Index, NDTI) treated with MCP, between 1/1992 - 6/2003, were obtained from IMS Health. The mean age for the case-series was 60 years and 2/3 were female. The mean dose was 33 mg/day with mean duration of 753 days (-108 weeks). Most of the known use was for GERD (gastroesophageal reflux disease), or acid reflux, whose main symptom is heartburn. Only 14% of use was for gastroparesis.
The marketing of cisapride for GERD in 1993 had an inverse impact on the sales of MCP, which reversed when cisapride was withdrawn from the market due to QT wave prolongation. Nearly 1/4 of MCP use was in persons, mostly females, over 70 years of age. This descriptive analysis reinforced the fact that a meaningful percentage ( 15-20%) of MCP is used long-term (off-label) in persons (elderly females) who are at the highest risk of TD. The authors reflect on the impact of these prescribing practices given the ‘paucity of evidence that MCP improves the quality of life” and the risk of a life-changing, potentially irreversible neurological disorder.
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It is my opinion that the defendants have not acted as a reasonable and prudent drug manufacturer and breached their standard of care. Given clear evidence of causality, the well-documented use greater than 12 weeks, and given the strong probability of increased risk for TD conditional on that greater exposure the defendants, should, at a minimum (1) assess the risk of TD beyond 12 weeks of exposure to determine if it is no different than that seen within the approved shorter termed exposure where the benefit-risk balance is considered by the FDA to be acceptable; (2) affirm efficacy beyond 12 weeks for the relevant indication(s) and reestablish that benefit - risk balance with the results from choice #1. The defendants had a responsibility to petition the FDA to update the label and reflect new information. Yet, the defendants have chosen to do neither. As a result, persons continue to be harmed to this day as demonstrated by Kenney (2008). The defendants fell below its standard of care in not reporting to the FDA and treating physicians the data available regarding long term use of metoclopramide. If the defendants would properly inform the FDA and the prescribers about the risk of TD then thousands of injuries from this drug could be prevented. Metoclopramide - as it was marketed and distributed by defendants at the time of Mr. Burnett's ingestion of the drug - was unreasonably dangerous and the information and warnings supplied with the drug were inadequate.”
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