DESCRIPTION & OBJECTIVES

The study of the physical and chemical properties of a drug, and its dosage form, as related to the onset, duration, and intensity of drug action, including coconstituents and mode of manufacture. Drugs are substances intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease. Drugs are given in a variety of dosage forms or drug products such as solids (tablets, capsules), semisolids (ointments, creams), liquids, suspensions, emulsions, etc, for systemic or local therapeutic activity. Drug products can be considered to be drug delivery systems that release and deliver drug to the site of action such that they produce the desired therapeutic effect and are also designed specifically to meet the patient's needs including palatability, convenience, and safety. Biopharmaceutics examines the interrelationship of the physical/chemical properties of the drug, the dosage form (drug product) in which the drug is given, and the route of administration on the rate and extent of systemic drug absorption. The importance of the drug substance and the drug formulation on absorption, and in vivo distribution of the drug to the site of action, is described as a sequence of events that precede elicitation of a drug's therapeutic effect. 

INTENDED LEARNING OUTCOMES

Biopharmaceutics is an integral component of the overall development cycle of a drug. Evaluation begins during the drug discovery process, proceeds through compound selection, preclinical efficacy and safety testing, formulation development, clinical efficacy studies, and post approval stages. At each stage, biopharmaceutical scientists interface with in multiple disciplines including discovery chemistry and biology, drug safety assessment, clinical development, pharmaceutical development, regulatory affairs, marketing, and manufacturing.

The preclinical development stage encompasses aspects of both drug discovery and drug development. Depending on the desired therapeutic action, the target blood concentration–time profile must be considered with respect to Cmax, tmax, AUC, clearance, accumulation, and dose proportionality. Species effects are also an important consideration since ADME. Understand the concept of ADME of drug in human body.

Determine the various pharmacokinetic parameters from either plasma concentration or urinary excretion data for drug. Describe the physicochemical and physiological factors that influence the absorption of drugs from enteral and parenteral routes of administration, their distribution within the body, and their routes and mechanisms of elimination.

Explain how dose, bioavailability, rate of absorption, apparent volume of distribution, total clearance, and elimination half-life affect the plasma concentrations of a drug after administration of a single dose. Helps us to determine the time-course of systemic accumulation of a drug administered by infusion or multiple doses.

READINGS

1. Li, A.P., 2004. In Vitro Approaches for Evaluation of Drug Efficiency and Toxicity. CRC Press, LLC, USA. 

2. Niazi, S., 2009. Handbook of Pharmaceutical Manufacturing Formulations: Compressed Solid Products. 2nd Ed. Informa Health Care, USA. 

3. Shargel, L., S. Wu-Pong and A.B.C. Yu, 2012. Applied Biopharmaceutics and Pharmacokinetics. 6th ed., McGraw-Hill, Medical Pub. Division, New Delhi, India. 

4. Schoenwald, R.D., 2002. Pharmacokinetics in Drug Discovery and Development, CRC Pres, LLC, USA.