Postmarketing Assessment of Sildenafil in Terms of Safety and Efficacy

Paick, Jae Seung

Abstract

PURPOSE
The main purpose of postmarketing surveillance of drugs is to better characterize the safety profile of drug therapy in routine clinical practice. Another goal is to confirm the effectiveness of the tested drugs in clinical practice. A postmarketing survey was undertaken to monitor the safety and efficacy of sildenafil citrate (SC) as a treatment for erectile dysfunction in Korean men.
MATERIALS AND METHODS
This 6-week, observational, open-label, uncontrolled, longitudinal, prospective study was conducted by 50 general hospitals across Korea. Men aged > or =20 years with erectile dysfunction who, in their physicians' opinion, should be treated with SC were enrolled for this study. To evaluate efficacy, the global efficacy assessment questionnaire (GEAQ) was administered before, and 2~4 weeks and 4~6 weeks following the initiation of SC therapy. Information regarding adverse drug reaction (ADR)s was collected on case-report forms designed for each visit and analyzed by the scientific committee of the study.
RESULTS
A total of 935 patients were enrolled, and 818 patients were assessable for safety. A total of 561 patients satisfied the requirements for efficacy analysis. Seventy-two patients (8.8%) experienced 99 ADRs over the 6 weeks. The most common ADRs were facial flushing (5.7%) and headache (2.0%). Eight patients discontinued the medication due to ADR. In response to the global efficacy assessment question, 91.4% of patients reported that SC improved their erectile function. Unlike the results of clinical trials, 67.2% of the population studied required 50 mg sildenafil to attain satisfactory erection.
CONCLUSIONS
In this postmarketing surveillance study of Korean patients with erectile dysfunction treated in routine clinical practice, SC showed a satisfactory tolerability and efficacy profile that was consistent with that seen in randomized, controlled trials.