Prospective observational cohort safety study to monitor the introduction of a non-CFC formulation of salbutamol with HFA134a in England.

OBJECTIVE: To monitor the safety of a salbutamol MDI with a hydrofluoroalkane propellant (Ventolin Evohaler) during its introduction into primary care use in England. METHODS: Prospective observational cohort study. 1,365 GPs in England submitted data on 10,472 regular users of Ventolin MDI, over five 3-month periods of observation between October 1, 1998 and December 31, 1999. The primary aim was to compare event rates occurring before and after the introduction of Ventolin Evohaler. The secondary aim was a comparison of event rates between users of Ventolin Evohaler and Ventolin MDI. The main outcome measures were: indication for use of Ventolin MDI, assessment of disease severity, event rates during each period of observation; deaths, pregnancies, reported adverse drug reactions and reasons for discontinuation of MDI. Event rates were adjusted using a ratio for under-reporting derived from a validation study on 4.6% of the study population and stratified by severity of indication. RESULTS: The primary indication was asthma in 94%, distributed by severity as 47% mild, 44% moderate and 9% severe; 13% were children. By October 1999, 52.7% of the 8,973 remaining patients had transitioned to Ventolin Evohaler. There was no increase in major or minor events observed following the introduction of Ventolin Evohaler. No serious adverse events, abnormal pregnancy outcomes or deaths have been related to Ventolin MDI or Ventolin Evohaler. The validation study showed a degree of under-reporting. CONCLUSION: These results on a large cohort of community patients in England indicate that Ventolin Evohaler is well tolerated among asthmatics.

Evaluation of the safety of fexofenadine from experience gained in general practice use in England in 1997.

BACKGROUND: Fexofenadine is the active metabolite of the non-sedating anti-histamine terfenadine. Pre-licensing clinical trials in over 6000 patients suggested it was effective and well tolerated. OBJECTIVE: To assess the tolerability and safety of fexofenadine immediately after its availability on the UK market in March 1997. METHODS: Post-marketing non-interventional observational cohort study using the methodology of prescription-event monitoring. Exposure data derived from dispensed prescription details supplied in confidence by the Prescription Pricing Authority. Outcome data derived from questionnaires returned by general practitioners (GPs) in England between March and August 1997. RESULTS: Of the 35,817 questionnaires sent, 18,238 (50.9%) were returned, of which 16,638 contained useful data. These included 40% male (mean age 36+/-19 years) and 59% female (mean age 39+/-19 years). Most common indications were allergic rhinitis (55%), not specified (28%), urticaria, pruritus or rash (10%) and other indications (7%). There were 40 reports of adverse drug reactions in 27 patients. Less than 2% of patients stopped the drug because of side effects. Events reported after exposure to fexofenadine were uncommon and already reported in clinical trials. There were eight reports of possible cardiac side effects (palpitations, three; chest pain, three; arrhythmia, one; and chest tightness, one). None was felt to be serious. There were no drug interactions reported. None of the 30 deaths was related to fexofenadine. None of the three adverse outcomes from the 47 pregnancies reported was related to fexofenadine. CONCLUSION: Within the limitations for an observational cohort study, fexofenadine was found to be well tolerated and safe in 16,638 users in general practice in England.