Dräger C, Benziger D, Gao F, Berde CB Prolonged intercostal nerve blockade in sheep using controlled-release of bupivacaine and dexamethasone from polymer microspheres. Anesthesiology. 1998 Oct;89(4):969-79.
Holte K, Werner MU, Lacouture PG, Kehlet H Dexamethasone prolongs local analgesia after subcutaneous infiltration of bupivacaine microcapsules in human volunteers. Anesthesiology. 2002 Jun;96(6):1331-5.
Kopacz DJ, Bernards CM, Allen HW, Landau C, Nandy P, Wu D, Lacouture PG A model to evaluate the pharmacokinetic and pharmacodynamic variables of extended-release products using in vivo tissue microdialysis in humans: bupivacaine-loaded microcapsules. Anesth Analg. 2003 Jul;97(1):124-31, table of contents.
Kopacz DJ, Lacouture PG, Wu D, Nandy P, Swanton R, Landau C The dose response and effects of dexamethasone on bupivacaine microcapsules for intercostal blockade (T9 to T11) in healthy volunteers. Anesth Analg. 2003 Feb;96(2):576-82, table of contents.
Thornton PC, Grant SA, Breslin DS Adjuncts to local anesthetics in peripheral nerve blockade. Int Anesthesiol Clin. 2010 Fall;48(4):59-70. doi: 10.1097/AIA.0b013e3181f89af1. Review.
Vieira PA, Pulai I, Tsao GC, Manikantan P, Keller B, Connelly NR Dexamethasone with bupivacaine increases duration of analgesia in ultrasound-guided interscalene brachial plexus blockade. Eur J Anaesthesiol. 2010 Mar;27(3):285-8. doi: 10.1097/EJA.0b013e3283350c38.
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.