Pharmaceutical products potency determination

Traditionally, in pursuit of their structure-activity relationships, medicinal chemists had focused almost exclusively on finding compounds with greater and greater potency. However, these SARs often ended up with compounds that were unsuitable for development as pharmaceutical products. These compounds would be too insoluble in water, or were not orally bioavailable, or were eliminated too quickly or too slowly from mammalian bodies. Pharmacologists and pharmaceutical development scientists for years had tried to preach the need for medicinal chemists to also think about other factors that determined whether a compound could be a medicine. Table 1.1 lists a number of factors that determine whether a potent compound has what it takes to become a drug. Experimentally, it was difficult to quantitate these other factors. Often, the necessary manpower resources would not be allocated to a compound until it had already been selected for project team status. 

The microbiological methods used for the determination of CTC potency in body tissues and fluids, bulk products, and pharmaceutical formulations can be separated into two testing procedures (1) agar diffusion plate method (cylinder-plate) and (2) turbidimetric method. 

It is widely understood within the industry that risk is defined as the combination of the probability of harm and the severity of that harm. Within the pharmaceutical industry whenever risk is considered the equipment or product being assessed must be viewed in the context of the protection of the patient. From our perspective, analytical instruments may impact on the validity of data that determines the safety and efficacy of drug products, or on the quality of the drug product. They may also impact on the identity or potency of the drug product and therefore it is important to ensure that risk management is performed throughout the complete life cycle of the instrument. 

Analytical precision relative to the amount of degradation is the primary reason that determination of the increase in levels of degradation products rather than loss of potency is recommended. Potency results have been used when degradation well beyond the levels considered pharmaceutically acceptable were studied,... 

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