ABSTRACT
Regulatory approvals for the marketing of medicinal products authorize medical practitioners to prescribe drugs to a group of patients that are defined within the license of the medicinal product. However, such prescriptions are carried out in a controlled manner. Prior to being approved, the medicinal product will have been evaluated in a population pool containing fewer than 5,000 patients and in a predesigned environment where several factors may be lacking, such as the absence of women of childbearing potential, geriatric patients and paediatric patients. Therefore, it is not surprising that several major adverse drug reactions are detected only when the product has been prescribed to the general population. National and international regulatory bodies have devised systems for monitoring medicinal products after marketing, commonly known as postmarketing surveillance systems. Postmarketing surveillance refers to the process of monitoring the safety of drugs once they reach the market, after the successful completion of clinical trials. The primary purpose for conducting postmarketing surveillance is to identify previously unrecognized adverse effects as well as positive effects. The Yellow Card scheme, practiced in the United Kingdom and the Canada Vigilance Program adopted in the Canadian jurisdiction, are two of the most successful postmarketing surveillance systems implemented across the world. Therefore, this article intends to discuss postmarketing surveillance and its role in the context of the United Kingdom and Canadian jurisdictions with a view on presenting key aspects and measures that are employed for operating an efficient postmarketing surveillance system in regulated markets.
ABSTRACT
BACKGROUND: Oropharyngeal candidasis is a common opportunistic infection seen in immunocompromised patients. Fluconazole has a broad spectrum antifungal activity including a wide variety of candida species. Aim of the present investigation was to formulate and find out the relative efficacy of in situ gels of fluconazole. METHOD: The in situ gels were prepared using polymers which exhibited sol-to-gel phase transition due to change in specific physico-chemical parameters, such as ion triggered system using gellan gum (0.5% w/v) along with sodium carboxylmethylcellulose (0.35%w/v). The study design was bicenter, 'pseudo-randomised, single blind trial conducted in Mangalore., India, which includes 15 HIV positive patients, 15 patients with partial or completes dentures, and 15 patients who were treated with (active control) fluconazole tablets 100 mg/day for 14 days. Severity of disease was scored clinically before treatment and at clinical evaluations on day 3, 7, 14, 18, 21, 35, and 42. Semiquantitative microbiological cultures of oral swabs were also obtained on same days. RESULTS: All patients had mycological documented oropharyngeal candidiasis and were treated with fluconazole (0.5%w/v) in situ gels for 14 days Severity of disease was scored clinically before treatment and at different predetermined time intervals along with semi quantitative culture of oral swabs. The clinical response rate showed 97% cure after 14 days in the treated with in situ gel. In comparison, the control group treated with fluconazole tablets showed 85% improvement in symptoms of oral candidiasis. The patients suffering from HIV infection showed relapse in oral candidiasis at the end of 21 days. The patients having oral candidiasis due to partial or complete dentures showed complete recovery and were free from signs and symptoms of oral candidiasis. CONCLUSIONS: The in situ gel formulation of fluconazole was well tolerated with no severe adverse reaction and offers a better alternative to tablet formulation in the treatment of oropharyngeal candidasis. TRIAL REGISTRATION: Current Controlled Trails ISRCTN90634047.
