BCS

• What has more barriers, oral or IV drug delivery?

  Oral drug delivery
• What is a swallowing barrier in oral drug delivery?

  Difficulty in swallowing the dosage form
• What type of acid is present in the stomach?

  Hydrochloric acid (HCl)
• What role do enzymes play in oral drug delivery?

  They help break down drugs in the stomach
• What do bile salts do in the small intestine?

  They aid in the digestion of fats
• Why might hydrophobic drugs not dissolve well?

  They repel water and do not mix
• What is necessary for a drug to be absorbed?

  The solution must be lipophilic enough
• What are the two main absorption barriers for drugs?

  Solubility and permeability

  
• Which drug delivery method is easier to manufacture, oral or IV?

  Oral drug delivery
• What is a higher risk in IV drug delivery?

  Risk of contamination
• What are the steps in oral drug delivery?

  1. Dosage form disintegrates in the stomach
  2. Drug dissolves (depends on solubility)
  3. Drug is absorbed through GIT into circulation (depends on permeability)
• What happens to a tablet during disintegration?

  It breaks into smaller fragments
• What state do drug molecules change into during dissolution?

  From solid state to liquid state
• What is the solid state of drug molecules characterized by?

  Being packed into crystals
• What is the liquid state of drug molecules characterized by?

  Breaking bonds between molecules
• What is similar between blood circulation and IV administration?

  Both deliver drugs to the bloodstream

  
• What does the need for new trials depend on for drug A's capsule formulation?

  It depends on the drug properties
• What can the Biopharmaceutics Classification System (BCS) help determine?

  Whether in vivo testing is needed
• Which classes of drugs usually need in vivo testing?

  Class 2 and Class 4 drugs

  
• When are in vivo bioequivalence studies required?

  If the drug has a narrow therapeutic range
• What are the dangers of a narrow therapeutic range?

  Toxicity and ineffective therapy
• What types of administration require bioequivalence studies?

  Buccal/sublingual administration
• What is the purpose of bioequivalence studies?

  To compare plasma concentrations of drugs
• How many healthy volunteers are needed for bioequivalence studies?

  Minimum 12, maximum 100
• What happens if too much of a drug is given?

  It can be toxic
• What happens if too little of a drug is given?

  It can be ineffective
• What does the BCS stand for?

  Biopharmaceutics Classification System
• What is the purpose of the BCS?

  To provide guidelines on in-vitro testing
• What does the BCS aim to stop?

  Unnecessary in-vivo bioequivalence testing
• What is the benefit of the BCS for drug products?

  Reduces costs and increases speed to market
• What is the solubility threshold for a drug?

  Above 10 mg/mL is soluble
• Which class of drugs is most common in the BCS?

  Class 2 drugs
• What is the rate limiting step for Class I drugs?

  Gastric emptying
• What is the rate limiting step for Class II drugs?

  Dissolution
• What is the rate limiting step for Class III drugs?

  Intestinal permeability
• What is a Biowaiver in the context of BCS?

  • Waives the need for in-vivo testing
  • Saves time and money
  • Applicable for certain re-formulations
• What conditions must be met for BCS bio-waivers?

  Immediate-release solid oral dosage forms
• What type of drug substances can request waivers?

  Class 1 drug substances
• What is the FDA definition of highly soluble drugs?

  Soluble in 250 ml of aqueous media
• What is the significance of 250 ml in bioequivalence studies?

  It represents stomach volume in fasting volunteers