Christopher James Foti

Can light absorption and photostability data be used to assess the photosafety risks in patients for a new drug molecule

Photosafety assessments are recommended for all new drug candidates intended for clinical use. In 2002, Testing guidances were issued by the regulatory authorities in the USA (2003) and Europe (2002). A key requirement is to measure the absorption of UV-visible light by a compound in the 290-700 nm range and to assess photostability. Further photosafety evaluation is recommended for molecules which absorb light energy in this region and may be unstable in light. Consequently, the current guidances do not specify what constitutes a significant level of light absorbance or photoinstability. The current study was undertaken to determine the level of light absorption by measuring the molar extinction coefficients (MEC) of a wide range of compounds reported in the literature to have known photosafety issues in humans. The results have shown that all compounds tested have absorbance intensities significantly above an MEC threshold of 1000 L mol(-1)cm(-1) and also display a wide range of photoinstability. The measurement of light absorption is a contributing part of an overall pre-clinical photosafety risk assessment process, whereas photostability assessments have proven to have limited value. Molecules with an MEC less than 1000 L mol(-1)cm(-1)are deemed less of a photosafety risk since this low level of light absorption is unlikely to prove harmful.

Recent Trends in Product Development and Regulatory Issues on Impurities in Active Pharmaceutical Ingredient (API) and Drug Products. Part 1: Predicting Degradation Related Impurities and Impurity Considerations for Pharmaceutical Dosage Forms

The American Association for Pharmaceutical Scientists (AAPS) Workshop on Predicting and Monitoring Impurities in API and Drug Products: Product Development and Regulatory Issues was held on October 13–14, 2012 at the McCormick Place in Chicago, IL, USA. The goal of the workshop was to discuss control strategies of chemical and physical changes of active pharmaceutical ingredients (API) and drug products in the drug development process. These changes can affect both the safety and efficacy of drugs; therefore, the ability to rapidly predict and assess the potential for drug product performance changes for impurity formation and the associated safety concerns are important parts of speeding the development of innovative drug therapies. The workshop consisted of four different sessions. Each session focused on separate fundamental issues to build a comprehensive understanding of the physical and chemical processes that impact drug degradation, the control of impurities and the impact of these factors on safety and regulatory areas. Taken together, this comprehensive understanding is used to achieve a more robust development process that enables predictability with a concomitant assurance of safety and efficacy. Innovative methodologies for development of effective stability control strategies were also presented. This article summarizes Sessions 1 and 2 of the American Association for Pharmaceutical Scientists (AAPS) Workshop on Predicting and Monitoring Impurities in API and Drug Products: Product Development and Regulatory Issues and addresses of predicting degradation related impurities and impurity considerations for pharmaceutical dosage forms. Sessions 3 and 4 of the American Association for Pharmaceutical Scientists (AAPS) Workshop on Predicting and Monitoring Impurities in API and Drug Products: Product Development and Regulatory Issues are summarized in Recent Trends in Product Development and Regulatory Issues on Impurities in Active Pharmaceutical Ingredient (API) and Drug Products Part 2: Safety Considerations of Impurities in Pharmaceutical Products and Surveying the Impurity Landscape published separately.