The clinical testing of experimental drugs is done in different phases, each successive phase involving more patients. The Phase 1/2a Cethrin trial was designed to test safety, and it was an open-label trial, meaning both patients and physicians knew who received the therapy. The Phase 1/2a trial was conducted by clinical investigators with many years of neurosurgery training and experience. The principal clinical investigator was Dr. Michael Fehlings MD PhD of the University of Toronto. Dr Fehlings and his colleagues have presented the results of this trial at international meetings and published their conclusions.
The next phase will be a Phase 2B trial, designed as a placebo-controlled, double-blind trial to test efficacy. That means that neither patient nor physician will know who receives the therapy, but safety is ensured by an independent review board. Results from the Phase 2b trial will only be known once completed and unmasked.
Placebo-controlled trials are essential to drug approval because disorders of the central nervous system often show substantial “placebo effects” . A patient with positive thinking who works to get better often shows better recovery. To ensure drug efficacy, generally, two pivotal trials are needed for approval. Cethrin has been granted Fast Track status by the FDA, allowing for accelerated review in the U.S. In addition, the drug’s Orphan Drug status and the significant need for effective therapies for SCI positions Cethrin to be approved with a successful pivotal study.