Lee SH, Yang YJ, Kim KM, Chung BC Altered urinary profiles of polyamines and endogenous steroids in patients with benign cervical disease and cervical cancer. Cancer Lett. 2003 Nov 25;201(2):121-31.
Löser C, Fölsch UR, Paprotny C, Creutzfeldt W Polyamines in colorectal cancer. Evaluation of polyamine concentrations in the colon tissue, serum, and urine of 50 patients with colorectal cancer. Cancer. 1990 Feb 15;65(4):958-66.
Russell DH Increased polyamine concentrations in the urine of human cancer patients. Nat New Biol. 1971 Sep 29;233(39):144-5.
Tsoi TH, Chan CF, Chan WL, Chiu KF, Wong WT, Ng CF, Wong KL Urinary Polyamines: A Pilot Study on Their Roles as Prostate Cancer Detection Biomarkers. PLoS One. 2016 Sep 6;11(9):e0162217. doi: 10.1371/journal.pone.0162217. eCollection 2016.
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.
