Cosman F, Shen V, Xie F, Seibel M, Ratcliffe A, Lindsay R Estrogen protection against bone resorbing effects of parathyroid hormone infusion. Assessment by use of biochemical markers. Ann Intern Med. 1993 Mar 1;118(5):337-43. Erratum in: Ann Intern Med 1994 Apr 15;120(8):698.
Henry JG, Mitnick M, Dann PR, Stewart AF Parathyroid hormone-related protein-(1-36) is biologically active when administered subcutaneously to humans. J Clin Endocrinol Metab. 1997 Mar;82(3):900-6.
Hodsman AB, Fraher LJ, Ostbye T, Adachi JD, Steer BM An evaluation of several biochemical markers for bone formation and resorption in a protocol utilizing cyclical parathyroid hormone and calcitonin therapy for osteoporosis. J Clin Invest. 1993 Mar;91(3):1138-48.
Horwitz MJ, Tedesco MB, Sereika SM, Hollis BW, Garcia-Ocaña A, Stewart AF Direct comparison of sustained infusion of human parathyroid hormone-related protein-(1-36) [hPTHrP-(1-36)] versus hPTH-(1-34) on serum calcium, plasma 1,25-dihydroxyvitamin D concentrations, and fractional calcium excretion in healthy human volunteers. J Clin Endocrinol Metab. 2003 Apr;88(4):1603-9.
Orloff JJ, Wu TL, Heath HW, Brady TG, Brines ML, Stewart AF Characterization of canine renal receptors for the parathyroid hormone-like protein associated with humoral hypercalcemia of malignancy. J Biol Chem. 1989 Apr 15;264(11):6097-103.
Plotkin H, Gundberg C, Mitnick M, Stewart AF Dissociation of bone formation from resorption during 2-week treatment with human parathyroid hormone-related peptide-(1-36) in humans: potential as an anabolic therapy for osteoporosis. J Clin Endocrinol Metab. 1998 Aug;83(8):2786-91.
Stewart AF, Cain RL, Burr DB, Jacob D, Turner CH, Hock JM Six-month daily administration of parathyroid hormone and parathyroid hormone-related protein peptides to adult ovariectomized rats markedly enhances bone mass and biomechanical properties: a comparison of human parathyroid hormone 1-34, parathyroid hormone-related protein 1-36, and SDZ-parathyroid hormone 893. J Bone Miner Res. 2000 Aug;15(8):1517-25.
Stewart AF, Wu T, Goumas D, Burtis WJ, Broadus AE N-terminal amino acid sequence of two novel tumor-derived adenylate cyclase-stimulating proteins: identification of parathyroid hormone-like and parathyroid hormone-unlike domains. Biochem Biophys Res Commun. 1987 Jul 31;146(2):672-8.
Syed MA, Horwitz MJ, Tedesco MB, Garcia-Ocaña A, Wisniewski SR, Stewart AF Parathyroid hormone-related protein-(1--36) stimulates renal tubular calcium reabsorption in normal human volunteers: implications for the pathogenesis of humoral hypercalcemia of malignancy. J Clin Endocrinol Metab. 2001 Apr;86(4):1525-31.
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.