Drug substances defined

For drug substances defined as hydrates or solvates, an assay value consistent with the anhydrous, solvent-free basis can be calculated where the amount of water or solvents subtracted in the denominator is the difference between the measured and theoretical amounts. 

For a continuous SMB process, the specific identified amount or batch produced is defined by unit of time in such a way that ensures a homogeneous material and quality within specified limits. In the case of a continuous SMB production run a batch is defined by the amount produced in a fixed time interval. A time limitation during manufacturing using SMB is established by the same fixed time interval as the batch. The duration of the production phase is thus established, which does not affect the quality of the drug substance [66]. 

AUC.dat Sixty-nine subjects were exposed to three different medications containing the same drug substance in a test of equivalence each had blood samples withdrawn at defined time points after administration so as to obtain a curve of plasma level of drug vs. time. The area under such a curve is a measure for the amount of medication the subject s body absorbed through... 

Drug substance Heterogeneous mixture Broad specifications during development Specifications may change during development Single entity high chemical purity Exception racemic mixtures Specifications well defined early in development... 

This chapter provides an introduction to the pharmaceutical sector, and the business of developing new active pharmaceutical ingredients (API). Crystallization is the preferred method of isolating commercial API products because it offers a highly efficient means of purification. The crystallization process is also where the physical properties of the drug substance are defined. These properties can have a significant impact on the formulated product and process, and eventually on the drug release profile in the patient. 

The critical path between nomination of a new drug substance and its entry to the marketplace is almost exclusively defined by the clinical trials programme. Typically this includes the following three phases ... 

Is the BCS that was developed with reference to chemically characterized and well-defined synthetic drug substances relevant for application and or adoption to botanical preparations (8) If one assumes, as is reasonable, that bioavailability of the active component(s) in a botanical dosage form depends on both solubility and permeability, the solubility of the botanical extract could be controlled through appropriate formulation technology and dissolution testing. The applicability of the BCS to botanical preparations will certainly be increasingly researched, debated, and discussed in the coming years. 

Defining the Actual Research Approach to the New Drug Substance Charles G. Smith 329... 

A drug substance must be chemically and physically characterized prior to incorporation into a new dosage form. Preformulation work provides the type of information needed to define the nature of the drug substance, as thoroughly as possible, and this then provides the framework for the drug s combination with pharmaceutic ingredients in the fabrication of a dosage form. 

A stability-indicating method is a validated quantitative analytical procedure that can detect the changes with time in the pertinent properties of the drug substance and drug product under defined storage condition. A stability-indicating assay method accurately measures the active ingredient(s) without interference from other peaks and is sensitive... 

A significant change for a drug substance or product as per ICH guideline is defined as follows ... 

Starting materials can be defined as the raw materials that form the basis of a chemical reaction as a part of the synthesis of an intermediate in the production of a drug substance. Catalysts typically include any material added to a mixture to accelerate, control, or otherwise modify a chemical reaction. Intermediates are those products of a synthesis scheme that will undergo further reaction. By-products are the side-products of a chemical reaction, and may include conjugates, dimers, enantiomers, unintended salts or free-bases, over-substitution, others. These types of impurities are usually considered to be process impurities and are not expected to increase in concentration over time. 

Drug substance and drug product undergo enormous testing efforts before they can be administered to patients. The specifications to ensure the product quality are defined in the early development phase and will be monitored through the whole life cycle. 

The sterility test is applicable for determining whether drug substances, preparations, or other pharmacopeial articles are sterile as defined by the compendial method. A satisfactory result only indicates that no contaminating microorganisms have been found in the sample examined rmder the conditions of the test. Therefore, the result is a function of the efficiency of the adopted sampling plan. Compendial references to sterility testing include USP 24 Chapter (71) Sterility Tests the Ph. Eur. 3rd ed.. Biological Tests 2.6.1, Sterility and the JP Xlll 45, Sterility Test. 

There is a misconception that drugs and medicines are quite different. The term drug carries with it the connotation of addiction, abuse and crime, but, in fact, medicines are just a subset of drugs. Drugs are defined as substances that can alter the biochemical processes in the body and medicines are those drugs that have a beneficial effect. 

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