Cheng MP, René P, Cheng AP, Lee TC Back to the Future: Penicillin-Susceptible Staphylococcus aureus. Am J Med. 2016 Dec;129(12):1331-1333. doi: 10.1016/j.amjmed.2016.01.048. Epub 2016 Feb 26.
Kirby WM EXTRACTION OF A HIGHLY POTENT PENICILLIN INACTIVATOR FROM PENICILLIN RESISTANT STAPHYLOCOCCI. Science. 1944 Jun 2;99(2579):452-3.
Nissen JL, Skov R, Knudsen JD, Ostergaard C, Schønheyder HC, Frimodt-Møller N, Benfield T Effectiveness of penicillin, dicloxacillin and cefuroxime for penicillin-susceptible Staphylococcus aureus bacteraemia: a retrospective, propensity-score-adjusted case-control and cohort analysis. J Antimicrob Chemother. 2013 Aug;68(8):1894-900. doi: 10.1093/jac/dkt108. Epub 2013 Apr 18.
Pilot Randomised Controlled Trial of Penicillin Versus Flucloxacillin for Definitive Treatment of Invasive Penicillin Susceptible Staphylococcus Aureus
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.