[Profile of Generic Drugs Associated with the Discontinuation of the Supply].

A consistent and uninterrupted supply of pharmaceuticals is essential for optimal pharmacotherapy. However, some cases of supply disruptions and recalls have been reported. In particular, the withdrawal of some drugs from the market was occurred in recent year. Nevertheless, the characteristics of these drugs were unknown. The aim of this study was to analyze the ratio of generic drugs and the profile of generic drugs that have been withdrawn from the market. Data were collected from a drug information database for the period between April 2017 and March 2022 and analyzed for characteristics, such as price, number of suppliers, and reasons for withdrawal. The results showed a 1.4-fold increase in the number of drugs discontinued in 2021 compared with that in 2017, with 78.6% of the drugs discontinued being generic drugs. The proportion of discontinued generic drugs costing less than 10 yen (29.2%) was higher than those remaining on the market (15.0%). Additionally, the proportion of withdrawn generic drugs sold by four or more suppliers (67.6%) was higher than those that remained in the market (38.4%). In most cases (78.8%), the reasons for the discontinuation of these generic drugs were not disclosed. This study showed that most drugs withdrawn in Japan during the study period were generic drugs, characterized by low prices or many suppliers. Our study contributes to the understanding of the instability in the pharmaceutical supply chain in Japan.

Protective effect of cyclic AMP against cisplatin-induced nephrotoxicity.

We reported earlier that reactive oxygen species are implicated in necrotic injury induced by a transient exposure of cultured renal tubular cells to a high concentration of cisplatin but not in apoptosis occurring after continuous exposure to a low concentration of cisplatin. We report here the protective effect of cyclic AMP against cisplatin-induced necrosis in cultured renal tubular cells as well as cisplatin-induced acute renal failure in rats. Several pharmacological agents that stimulate cyclic AMP signaling, including the nonhydrolyzable cyclic AMP analogue dibutyryl cyclic AMP, forskolin, 3-isobutyl-1-methylxanthine, and a prostacyclin analogue, beraprost, prevented cisplatin-induced cell injury in a protein kinase A-dependent manner. Cisplatin enhanced lipid peroxidation, decreased CuZn superoxide dismutase (SOD) while enhancing MnSOD activity, and increased cellular tumor necrosis factor-alpha (TNF-alpha) content. The elevation of TNF-alpha content and cell injury induced by cisplatin were attenuated by p38 mitogen-activated protein kinase (MAPK) inhibitors including SB203580 and PD169316. Indeed, cisplatin increased the number of phosphorylated p38 MAPK-like immunoreactive cells. These intracellular events were all reversed by antioxidants such as N-acetylcysteine (NAC) and glutathione or cyclic AMP analogues. The in vivo acute renal injury after cisplatin injection was associated with the elevation of renal TNF-alpha content. The cisplatin-induced renal injury and the increase in TNF-alpha content were reversed by NAC or beraprost. These findings suggest that cyclic AMP protects renal tubular cells against cisplatin-induced oxidative injury by obliterating reactive oxygen species and subsequent inhibition of TNF-alpha synthesis through blockade of p38 MAPK activation.