To the Editor: The Experimental Drugs Section (EDS) of the Drug Safety and Evaluation Branch of the Therapeutic Goods Administration (TGA) administers the clinical trial notification (CTN) and clinical trial exemption (CTX) arrangements for unapproved medicines used in clinical trials. These arrangements provide an avenue of “exemption”, whereby medicines that have not been approved for marketing in Australia are able to be supplied to patients within the context of a clinical trial approved by a human research ethics committee working under the guidelines of the Australian Health Ethics Committee (a subcommittee of the National Health and Medical Research Council). Although these arrangements cover only clinical trials in which unapproved medicines are used, a substantial number of such trials are carried out in Australia each year. (Clinical trials using unapproved medical devices that also use the CTN/CTX arrangements are administered by the TGA’s Office of Blood, Devices and Tissues and are not included in these statistics.)

The EDS often receives queries from stakeholders requesting some form of basic statistical data with respect to clinical trial activity in Australia. The EDS intends to begin use of a new database in 2007 for recording CTNs and CTXs notified to the TGA. It is hoped that this will enable us to publish a basic statistical subset of clinical trial information on an annual basis. As a prelude to this capability, we have manually compiled a few simple statistics on clinical trials notified within the financial year 2004–05.

Box 1 breaks down the trials conducted into various body systems or treatment areas. There were 739 separate clinical trials of unapproved medicines commenced over the 1-year period. As many of these are multicentre trials, there are a much greater number of actual trial sites involved. (A good measure of the number of trial sites is simply the raw CTN notification figures, numbering 2776 for the same period.)

Box 2 breaks down the trial numbers into the various phases of drug development. Although this is not relevant to all trials, these figures give an indication of the main areas of drug development research currently being conducted in Australia.

Given the number of multicentre trials being carried out, we did not think it useful to break down trial numbers by state and territory. We trust that these data convey some idea of current clinical trial activity with respect to unapproved medicines in Australia.