Progressive multifocal leukoencephalopathy analyzed using the Japanese Adverse Drug Event Report database.

Area of Science:

• Pharmacovigilance
• Neurology
• Immunology

Background:

• Progressive multifocal leukoencephalopathy (PML) is a rare, opportunistic brain infection.
• PML development is associated with immunomodulatory drugs, including anticancer, immunosuppressive, and biologic agents.
• The increasing use of these therapies necessitates understanding drug-associated PML incidence.

Purpose of the Study:

• To analyze the incidence profile of drug-associated PML in real-world clinical practice in Japan.
• To identify trends in PML reports related to specific drug classes and patient demographics.

Main Methods:

• Retrospective observational study using the Japanese Adverse Drug Event Report (JADER) database.
• Analysis of PML reports (preferred term: "progressive multifocal leukoencephalopathy") from April 2004 to March 2022.
• Evaluation of causative drugs, underlying diseases, and patient age impact on annual PML report numbers.

Main Results:

• Identified 361 PML events from 773,966 reports in the JADER database.
• Observed a gradual increase in PML reports and reporting ratios over the past decade.
• Annual PML reports associated with biologics, immunosuppressants, and antineoplastic drugs showed an increasing trend.
• PML reports increased in females aged ≥30 years and males aged ≥50 years.

Conclusions:

• The increasing number of PML reports in Japan is linked to evolving treatments for malignancies and autoimmune diseases.
• Growing utilization of biologics, immunosuppressive agents, and antineoplastic agents contributes to the rise in drug-associated PML.
• Continued pharmacovigilance is crucial for monitoring PML associated with immunomodulatory therapies.