Merck suspends Stimuvax programme

Merck has temporarily suspended its Stimuvax (BLP25 liposome vaccine) clinical programme on a worldwide scale after a patient developed encephalitis, an acute inflammation of the brain.

The German pharmaceutical company has said that "effective immediately" all enrollments into trials and treatment of patients in current trials will be put on hold.

The decision was taken "in alignment with the US Food and Drug Administration's (FDA) clinical hold placed on the Investigational New Drug (IND) application for Stimuvax," according to Merck in a statement.

The Stimuvax vaccine is currently being tested in both phase II and phase III clinical trials for the treatment of non-small cell lung carcinoma (NSCLC) and breast cancer after being granted fast-track status in September 2004 by the FDA.

The patient who developed encephalitis was participating in a phase II exploratory trial using the vaccine in patients with multiple myeloma. This trial involved an intensified schedule of low-dose cyclophosphamide, a treatment not used in other Stimuvax studies.

The affected ongoing trials affected by the suspension include the NSCLC studies START and INSPIRE and the breast cancer study STRIDE.

"The company considers patient safety of paramount importance," said Merck "and will continue to work closely with the regulatory authorities, particularly with the FDA, to evaluate the implications of the adverse reaction on the clinical development programme for Stimuvax and determine the most suitable course of action."