The Efficacy and Safety of Vardenafil in the Treatment of Pulmonary Arterial Hypertension
Condition: Pulmonary Hypertension
MeSH terms: Hypertension, Pulmonary; Pulmonary Arterial Hypertension; Hypertension
Study type: Interventional
Phase: Phase 3

Summary: 
      The purpose of this study is to evaluate the efficacy and safety of vardenafil in the
      treatment of pulmonary arterial hypertension.
    

Detailed description: 
      Pulmonary arterial hypertension (PAH), defined as a mean pulmonary artery pressure ≥25 mmHg
      with a pulmonary capillary wedge pressure ≤15 mmHg measured by cardiac catheterization, is a
      disorder that may occur either in the setting of a variety of underlying medical conditions
      or as a disease that uniquely affects the pulmonary circulation. Irrespective of its
      etiologies, PAH is a serious and often progressive disorder that results in right ventricular
      dysfunction and impairment in activity tolerance, and may lead to right-heart failure and
      death. The pathogenesis of PAH is complex and incompletely understood, but includes both
      genetic and environmental factors that alter vascular structure and function.

      In recent years, several new drugs have been developed for the treatment of pulmonary
      arterial hypertension (PAH), including continuous intravenous epoprostenol, inhaled iloprost,
      subcutaneous trepostinil, oral bosentan, and oral beraprost. In addition, there is increasing
      evidence for the therapeutic effectiveness of the phosphodiesterase-5 (PDE-5) inhibitor
      sildenafil in PAH. Phosphodiesterases are a superfamily of enzymes that inactivate cyclic
      adenosine monophosphate and cyclic guanosine monophosphate, the second messengers of
      prostacyclin and nitric oxide (NO) .The phosphodiesterases have different tissue
      distributions and substrate affinities. Interestingly, PDE-5 is abundantly expressed in lung
      tissue, thus offering as target molecule for PAH treatment concepts.

      The three commercially available PDE-5 inhibitors (sildenafil, vardenafil, and tadalafil) are
      currently approved for the treatment of erectile dysfunction . These inhibitors are now
      receiving attention for their activity in the pulmonary vasculature. Sildenafil has been
      proved to improve the exercise capacity and pulmonary hemodynamics of PAH patients, however,
      there are few reports regarding the use of vardenafil or tadalafil on the pulmonary
      vasculature. Although sildenafil, vardenafil, and tadalafil act on the same enzyme, these
      drugs exhibit different pharmacokinetics and selectivity, and therefore may not be equally
      efficacious in the pulmonary vascular bed. As vardenafil has a more than 20-fold greater
      potency than sildenafil for inhibiting purified PDE-5, we assume that it will show more
      favorable clinical and side-effect profiles in treating PAH.

      This is a prospective, randomized, placebo-controlled, pilot study to evaluate the efficacy
      and safety of vardenafil in the treatment of pulmonary arterial hypertension.
    

Intervention name(s): Vardenafil; Placebo; Vardenafil
Intervention type(s): Drug; Drug; Drug
Intervention description(s): vardenafil tablet 5mg once-daily orally in the first 4 weeks while 5mg twice-daily orally in the following 8 weeks.; Placebo tablet 5mg once-daily orally in the first 4 weeks while 5mg twice-daily orally in the following 8 weeks.; Patients in all the 2 arms will take vardenafil tablet 5mg twice-daily orally from week 13 to week 24(open-label).
Other intervention name(s): Levitra; Levitra
Intervention MeSH terms: Vardenafil Dihydrochloride
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary purpose: Treatment
Keywords: Pulmonary Hypertension