Validation and Reproducibility of the Updated French Causality Assessment Method: an Evaluation by Pharmacovigilance Centres & Pharmaceutical Companies.

OBJECTIVE: Assess the validity and reproducibility of the updated version of the French causality assessment method in conditions approaching real-life use. METHODS: A random sample of 31 drug-event pairs from the French pharmacovigilance database was assessed by the consensual judgement of three experts (gold standard). Separately, a team from a pharmacovigilance centre (PhVC) and another from a pharmaceutical company assessed these pairs using the current method, then with the updated method. To test the inter- and intra-rater reproducibility, two seniors and two juniors from a PhVC and a pharmaceutical company assessed the pairs twice with the updated method. A weighted kappa coefficient was used to measure the agreement of the two causality assessment methods with the consensual expert judgement (validity) as well as the agreement of the updated causality assessment over time (intra-rater reproducibility) and between evaluators (inter-rater reproducibility). RESULTS: Agreement between the current method and consensual expert judgement was fair for the PhVC team (weighted kappa [Kw] 0.33) and moderate for the pharmaceutical company team (Kw 0.41). For the updated method, agreement was better for both the PhVC (Kw 0.58) and the pharmaceutical company (Kw 0.52) teams. The inter- and intra-rater reproducibility of the updated method based on the intrinsic imputability was satisfactory overall (Kw 0.30-0.91). Discrepancies between evaluations from PhVC and pharmaceutical companies were observed with the updated method. CONCLUSION: The updated method performed better than the current one for drug causality assessment, suggesting that it should be used in routine pharmacovigilance.

Updating the French method for the causality assessment of adverse drug reactions.

The Imputability Working Group (CRI) updated the French drug reaction causality assessment method. This tripartite group is made up of staff from the French network of regional pharmacovigilance centres, pharmaceutical companies, and the French National Agency for the Safety of Medicines and Health Products (ANSM). After reviewing the strengths and weaknesses of the previous method, several ideas for improvement were proposed: a better-worded and more discriminating scale for certain chronological and semiological criteria, a larger scale for the intrinsic score (increased from 5 to 7 levels), a new bibliographical scale to differentiate between expected and unexpected adverse drug reactions, and a new informativeness scale.

Cysteamine toxicity in patients with cystinosis.

OBJECTIVE: To report new adverse effects of cysteamine. STUDY DESIGN: Detailed clinical information was obtained from the patients' physicians. RESULTS: New adverse events were reported in 8 of 550 patients with cystinosis treated with cysteamine in Europe during the last 5 years. Detailed clinical information was not available for 2 of these patients, 1 of whom died from cerebral ischemia. The 6 evaluable patients developed vascular elbow lesions (6/6), neurologic symptoms (1/6), bone and muscle pain (2/6), and/or skin striae (2/6). Analysis of biopsy specimens from the elbow lesions demonstrated angioendotheliomatosis with irregular collagen fibers. In 3 of the 6 patients, the daily cysteamine dose exceeded the recommended maximum of 1.95 g/m(2)/day. Dose reduction led to improvement of signs and symptoms in all 6 patients, suggesting a causal relationship with cysteamine administration. CONCLUSION: Cysteamine administration can be complicated by the development of skin, vascular, neurologic, muscular, and bone lesions. These lesions improve after cysteamine dose reduction. Doses >1.95 g/m(2)/day should be prescribed with great caution, but underdosing is not advocated.

[Not Available]. / Réactualisation de la méthode française d'imputabilité des effets indésirables des médicaments.

A tripartite group, entitled « CRI ¼ (for Cercle de réflexion sur l'imputabilité), involving French pharmacovigilance staff from the French network of the Regional centers of pharmacovigilance, from pharmaceutical companies, and from French Health Authorities (Agence française de sécurité sanitaire des produits de santé) has worked to update the French drug reaction assessment method. Following assessment of strengths and weaknesses of the previous method, several points for improvement are proposed : a more precise wording and a more discriminating scale for some of the chronological and semiological criteria, a wider distribution of the intrinsic score from 5 to 7 levels, a new bibliographic scale for differentiating expected and unexpected adverse drug reactions, and a new informativness scale. This updated method would lead to a more relevant assessment of relationship between a drug and the occurrence of an adverse reaction. Furthermore, this method is a teaching tool to assess the level of relationship between a drug and the occurrence of an adverse reaction.

[Update of the French drug reaction assessment method]. / Réactualisation de la méthode française d'imputabilité des effets indésirables des médicaments.

A tripartite group, entitled « CRI ¼ (for Cercle de réflexion sur l'imputabilité), involving French pharmacovigilance staff from the French network of the Regional centers of pharmacovigilance, from pharmaceutical companies, and from French Health Authorities (Agence française de sécurité sanitaire des produits de santé) has worked to update the French drug reaction assessment method. Following assessment of strengths and weaknesses of the previous method, several points for improvement are proposed: a more precise wording and a more discriminating scale for some of the chronological and semiological criteria, a wider distribution of the intrinsic score from 5 to 7 levels, a new bibliographic scale for differentiating expected and unexpected adverse drug reactions, and a new informativness scale. This updated method would lead to a more relevant assessment of relationship between a drug and the occurrence of an adverse reaction. Furthermore, this method is a teaching tool to assess the level of relationship between a drug and the occurrence of an adverse reaction.

Liver Transplantation because of Acute Liver Failure due to Heme Arginate Overdose in a Patient with Acute Intermittent Porphyria.

In acute attacks of acute intermittent porphyria, the mainstay of treatment is glucose and heme arginate administration. We present the case of a 58-year-old patient with acute liver failure requiring urgent liver transplantation after erroneous 6-fold overdose of heme arginate during an acute attack. As recommended in the product information, albumin and charcoal were administered and hemodiafiltration was started, which could not prevent acute liver failure, requiring super-urgent liver transplantation after 6 days. The explanted liver showed no preexisting liver cirrhosis, but signs of subacute liver injury and starting regeneration. The patient recovered within a short time. A literature review revealed four poorly documented cases of potential hepatic and/or renal toxicity of hematin or heme arginate. This is the first published case report of acute liver failure requiring super-urgent liver transplantation after accidental heme arginate overdose. The literature and recommendations in case of heme arginate overdose are summarized. Knowledge of a potentially fatal course is important for the management of future cases. If acute liver failure in case of heme arginate overdose is progressive, super-urgent liver transplantation has to be evaluated.