Prescription, Drug Development & Regulation PDF

# Classification of Medication based on Prescription Requirement ## Nonprescription Drugs * Are pharmaceutical products or drug preparations that can be dispensed even without the written order of a validly registered licensed physician, dentist, or veterinarian, for the use of consumers for the...

# Classification of Medication based on Prescription Requirement ## Nonprescription Drugs * Are pharmaceutical products or drug preparations that can be dispensed even without the written order of a validly registered licensed physician, dentist, or veterinarian, for the use of consumers for the prevention or symptomatic relief of minor or self-limiting ailments. * Simpler and safer drugs may be marketed for sale without a prescription. ## Prescription Drugs * Are pharmaceutical products or drug preparations that are to be dispensed only upon written order of a validly registered physician, dentist or veterinarian for the management or treatment of a condition or disease. * Are drugs that are deemed to require complex directions regarding their use. * They can be purchased only with a prescriber's direction (the prescription). ## Dangerous Drugs * Are pharmaceutical products referring to either prohibited or regulated drugs which require a special prescription form usually obtained from the Dangerous Drugs Board. * Are drugs that are considered to have significant potential for illicit use (due to addiction liability and other reasons). * Ranking based on their perceived social danger * Schedule I - banned from prescription or anything other than research use. * Schedule II - include strongly addicting drugs that nevertheless have important medical uses. * Schedule III to Schedule V - drugs that are progressively less addicting. ## Comparison of 3 Drugs in terms of Prescription Requirement | Drug | OTC | Rx Drug | Dangerous Drug | |---|---|---|---| | Prescription required | none | Ordinary prescription | Yellow prescription | | Number of Copies | none | One | RPh, MD, & Patient | | Ways of Identifying | No Rx sign | With Rx sign and additional label requiring prescription | With Rx sign and additional label requiring prescription and List A | | Recording required | No | Prescription book | Dangerous drug book | | Filing of Prescription | No | 2 years | 1 year | *Note: for poison drug - the prescription should be kept for 5 years and recorded in the poison book. ## How drugs are Discovered and Developed ### Drug Discovery and Design 1. **Identification of New, Previously Undiscovered, Biologically Active Compounds (HITS):** 2. **Chemical or Functional Group Modification of a HIT to Improve Pharmacological, Toxicological, Physicochemical, Pharmacokinetic Properties (LEAD COMPOUND):** 3. **LEAD OPTIMIZATION:** Modification of functional groups of lead compound to improve its recognition, affinity, and binding of pharmacophores for the targeted site. 4. **Rendering the lead compound into a DRUG CANDIDATE that is safe and suitable for use in human clinical trials, including preparation of a suitable DRUG FORMULATION.** ### FDA (Food and Drug Administration) * Is the government agency that mandates the conditions under which drugs intended for medical use are developed and tested. ### Drug Screening * Animal testing * Human trials (requires approval of an IND application) * Marketing for human use (requires approval of an NDA application) ### Animal Testing | Type of Test | Purpose | Subjects | |---|---|---| | Pharmacological profile | Determine all useful or toxic actions of the drug and their mechanisms | Mice, Rats, Dogs | | Reproductive toxicity | Detect fertility, teratogenic, and mutagenic effects | Mice, Rats, Rabbits | | Chronic toxicity | Long-term testing for toxic effects | Mice, Rats | ### FDA Ratings of Drug Safety in Pregnancy * **Pregnancy Category A:** Controlled studies in women fail to demonstrate a risk to the fetus in the first trimester (and there is no evidence of a risk in later trimesters), and the possibility of fetal harm appears remote. * **Pregnancy Category B:** Either animal reproduction studies have not demonstrated a fetal risk but there are no controlled studies in pregnant women, or animal reproduction studies have shown an adverse effect. * **Pregnancy Category C:** Drugs should be given only when the potential benefit justifies the potential risk to the fetus. * **Pregnancy Category D:** There is positive evidence of human fetal risk, but the benefits from use in pregnant women may be acceptable despite the risk. * **Pregnancy Category X:** The drug is contraindicated in women who are or may become pregnant. ## Human Clinical Trials | Type of Test | Purpose | Subjects | |---|---|---| | Phase I | Determine the useful dose range, pharmacokinetics, and minimal toxic effects | 25- 30 paid normal volunteers | | Phase II | Determine the efficacy of the drug on the target disease under highly controlled conditions | Hundreds of patients with the target disease | | Phase III | Determine the efficacy of the drug on the target disease under conditions of typical use | Hundreds to thousands of patients | ### Phase IV * Surveillance of toxicities reported during normal use. * This constitutes monitoring the safety of the new drug under actual conditions of use in large numbers of patients. ### Drug Development Timeline * **Year 0:** In Vitro studies and animal testing * **Year 2:** Lead compound * **Year 4 (IND):** Begins clinical trials * Phase I * Phase II * Phase III * Phase IV (postmarketing surveillance) * **Year 8-9 (NDA):** Drug metabolism and safety assessment, marketing. * **Year 20:** Generics become available ## How drugs are Monitored and Regulated ### Dangerous Drugs Board * The government agency tasked in creating policies in dealing with dangerous drugs, controlled substances, and illegal drugs. ### Philippine Drug Enforcement Agency (PDEA) * The lead anti-drug law enforcement agency. * Responsible for preventing, investigation, and combating any dangerous drugs, controlled precursors and essential chemicals. ### Dangerous Drugs: Regulatory Guidelines | Schedule | Description | |---|---| | Schedule I | Drugs not used medically. Not accepted as safe for use under medical supervision. High abuse potential. Possession and supply prohibited. | | Schedule II | Accepted medical use. High abuse potential. May lead to severe psychological and physical dependence. | | Schedule III | Accepted medical use. Less abuse (moderate) potential than Schedule II. May lead to moderate physical dependence or high psychological dependence. | | Schedule IV | Accepted medical use. Less abuse potential than Schedule III. Limited physical dependence and psychological dependence. | | Schedule V | Rx/OTC: Less abuse potential than Schedule IV. | ### Dangerous Drugs: Prescribing Guidelines | Schedule | Description | |---|---| | Schedule I | Not available for therapeutic use. | | Schedule II | Only available by a written prescription signed by prescriber & must be supplied within 72 hours. Cannot be refilled unless in case of emergency. | | Schedule III | May not be refilled more than 5 times or be dispensed or refilled more than 6 months after the prescription was issued. | | Schedule IV | May not be refilled more than 5 times or be dispensed or refilled more than 6 months after the prescription was issued. | | Schedule V | Available as prescription or nonprescription drug. | ## Drug Product Information ### Drug Nomenclature * **Chemical Name:** Complete description of chemical structure of drug. * **Generic Name:** Shortened scientific name based on active ingredient. * **Brand/Trade/Proprietary Name:** Name given by pharmaceutical company to distinguish their drug products from other competitors. ### Other Drug Information * **Active Pharmaceutical Ingredient (API):** A substance or compound that is intended to be used in the manufacture of a pharmaceutical product as a therapeutically active compound. * **Dosage Form:** The drug product type that contains a drug substance generally, but not necessarily, in association with excipient. * **Dosage Strength:** The concentration or potency of the known API. * **Excipient:** An ingredient, added intentionally to the drug substance which should not have pharmacological properties in the quantity used. * **Side Effects:** * A secondary unwanted effect that occurs due to drug therapy. * An undesired effect that occurs when the medication is administered regardless of the dose. * **Adverse Effects:** Noxious, unintended pharmacologic effects that occurs when a medication is administered correctly. * **Indication** The FDA-approved clinical use of a drug product based on substantial, scientifically supported evidence of its safety and efficacy in the given dosage form. * **Mode of Administration:** The manner and site where the drug product is to be introduced into or applied on the body. * **Pharmacologic Category:** Refers to the classification of the drug product based on its therapeutic action as specified in the product registration. * **Warnings:** Statements regarding the occurrence of potential hazards and undesirable effects associated with the use of the drug product and the limitation of its use. * **Precaution:** The instruction and the special care required in the use of the drug product to avoid undesired effects and to ensure its safe and effective use. * **Contraindication:** A statement regarding the conditions wherein the use of the drug product may cause harm to the patient.