From single-arm studies to externally controlled studies. Methodological considerations and guidelines.

Single-arm studies are sometimes used as pivotal studies but they have methodological limitations which prevent them from obtaining the high level of reliability as for a randomised controlled study which remains the gold standard in the evaluation of new treatments. The objective of this roundtable was to discuss the limitations of these single-arm studies, to analyse available and acceptable solutions in order to propose guidelines for their conduct and assessment. Single-arm studies themselves are intrinsically inappropriate for demonstrating the benefit of a new treatment because it is impossible to infer the benefit from a value obtained under treatment without knowing what it would have been in the absence of the new treatment. The implication is that comparison with other data is necessary. However this comparison has limitations due to (1) the post hoc choice of the reference used for comparison, (2) the confusion bias for which an adjustment approach is imperative and, (3) the other biases, measure and attrition among others. When these limitations are taken into account this should, first and foremost, lead to the conduct of externally controlled trials instead of single-arm trials as is proposed by the latest version of ICH E10. Moreover, the external control must be formalised in the study protocol with a priori selection of both the reference control and the formal method of comparison: test in relation to a standard, adjustment on individual data, a synthetic control group or matching-adjusted indirect comparisons (MAIC). Lastly, externally controlled studies must be restricted to situations where randomisation is infeasible. To be acceptable, these studies must be able to guarantee freedom from residual confusion bias, which is only truly acceptable if the observed effect is dramatic and the usual course of the disease is highly predicable.

Off-label prescriptions: how to identify them, frame them, announce them and monitor them in practice?

Following the Mediator crisis and the passage of the Health and Safety Law of December 2011, off-label prescriptions are a real concern shared by all those involved in healthcare system. Off-label, in the strictest sense of the term, is defined as all prescriptions that do not correspond to the summary of product characteristics (SPC), particularly those that fail to comply with the indications and dosage regimens defined by the marketing authorization (MA) for clear safety reasons. There are various rasons for off-label prescriptions, both conscious and unconscious. They are intended to respond to unmet medical needs, the needs of poorly studied populations or not studied at all in trials, but in relation to whom it is reasonable to extrapolate that MA would be given (common-sense prescriptions) and, additionally, to urgent public health needs (such as baclofen, pregnant women, and HIV drugs). All these prescriptions would deserve to be studied for a potential MA. However, there are off-label prescriptions that need to be restricted or even penalized in the case of compassionate prescriptions or unjustified prescriptions or prescriptions not based on any scientific grounds. Off-label prescriptions are not easy to track down because if the prescriber has to write "off-label" on his prescription, then clearly, in practice, he will only do so in exceptional cases. Neither the pharmacists who dispense the drug nor the Social Security that reimburses it, have access to the diagnosis (or targeted indication). Thus, in order to identify the off-label prescription, we must be able to cross reference the available databases (such as pharmacovigilance database, medicalized information system program [programme de médicalisation des systèmes d'information, PMSI], hospital drug formularies, general sample of beneficiaries [échantillon généraliste de bénéficiaires, EGB] or national inter-regional Health Insurance Information System [système national d'informations inter-régions d'Assurance maladie, SNIIRAM], sales data, and data from market surveys). The shared computerized patient file may resolve this problem. The temporary use recommendation (TUR) proposed by the Drug Safety Law will only partially deal with this problem for recently marketed molecules. This temporary and exceptional mechanism will authorize a recognized off-label prescription, which may be reimbursed and monitored for 3 years. These TURs will only concern a small portion of "off-label" drugs having yet a positive risk/benefit ratio (conditional MA) but this is far from matching with majority of off-label prescriptions. As such, and in order to improve the use of drugs, it is important to propose a control system for all "off-label" prescriptions with a dedicated committee: the "off-label" committee which would determine the frame of the "off-label" prescriptions.

The cost of treating high blood pressure in general practice in France.

In this study, the cost of having high blood pressure treated by French general practitioners was estimated, using an analysis of the computerized records for 28,015 patients with either hypertension or history of hypertension over three years. Costs due to visits, drugs, and complementary tests were included. The average annual cost of treatment was 597 euros (SD 377 euros). The annual average cost of drugs was 447 euros, and antihypertensive drugs 258 euros. The average annual cost of patients who were controlled throughout the period was 537 euros, patients who were normalized cost 595 euros, and patients who deteriorated cost 612 euros.