Bouley R, Pastor-Soler N, Cohen O, McLaughlin M, Breton S, Brown D Stimulation of AQP2 membrane insertion in renal epithelial cells in vitro and in vivo by the cGMP phosphodiesterase inhibitor sildenafil citrate (Viagra). Am J Physiol Renal Physiol. 2005 Jun;288(6):F1103-12. Epub 2005 Jan 11.
Fujiwara TM, Bichet DG Molecular biology of hereditary diabetes insipidus. J Am Soc Nephrol. 2005 Oct;16(10):2836-46. Epub 2005 Aug 10. Review.
Nielsen S, Kwon TH, Frøkiaer J, Agre P Regulation and dysregulation of aquaporins in water balance disorders. J Intern Med. 2007 Jan;261(1):53-64. Review.
Schrier RW, Cadnapaphornchai MA, Umenishi F Water-losing and water-retaining states: role of water channels and vasopressin receptor antagonists. Heart Dis. 2001 May-Jun;3(3):210-4. Review.
Schrier RW, Cadnapaphornchai MA Renal aquaporin water channels: from molecules to human disease. Prog Biophys Mol Biol. 2003 Feb;81(2):117-31. Review.
Pharmacologic Treatment of Congenital Nephrogenic Diabetes Insipidus
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
