Challenges in Analytical Development: The Need in Orthogonal Chromatographic Methods for a Small Molecule Project in Innovative Drug Development

Vladimir Ioffe

Analytical Development, Global R&D, Teva Pharmaceutical Industries, Ltd., Israel
e-mail: vladimir.ioffe@teva.co.il

The workshop is aimed at revelation of potential issues / challenges in analytical method
development in R&D in pharmaceutical industry. Participants will be exposed to an example of
logic in development of HPLC method(s) intended for support of chemical and pharmaceutical
development of a potential new drug. Such method(s) should be reliable, friendly to terminal users
(“QC’able”) and ensure full coverage of characterization of a drug substance / drug product.
Mindset of method development must be aimed at developing a method / methods set intended for release and stability studies testing, thus including stability indicating capability of analytical
procedure(s).

The workshop is based on the real case of development of an “HPLC package” to support
chemical development of an innovative project, where the API is a comparatively “simple” small
molecule – Oleyl α-Phenylglycinate. The molecule has a cis-double bond, a chiral center in α-
position to aromatic ring and a labile ester bond.

The product and starting materials for its synthesis (Phenylglycine and Oleyl Alcohol, which are
also its dominant degradation products) have extremely different polarity and lipophilicity. In a
“classic” RP HPLC method developed for this API, the peak of Phenylglycine elutes before solvent
front. The peak of Oleyl alcohol cannot be seen using UV detector due to lack of chromophore.
This caused a need in developing of complementary methods: the method for “Polar Impurities”
developed using a mixed-mode HPLC column and the method for Oleyl Alcohol – using a nonsilica based RP column and evaporative detector (ELSD or Corona CAD). These methods were
also adjusted for analysis of starting materials. Most challenging was achieving of a reliable
separation between Oleyl Alcohol and its trans-isomer.

In addition, enantioselective separation under normal phase chromatographic conditions has been developed to determine enantiomeric purity. This method was later upgraded to bioanalytical, with MS and MS/MS detectors equipped with APCI ion source.

The aim of workshop is to familiarize a mindset of the developer of HPLC methods and to converse the need in complementary “orthogonal” chromatographic procedures and diverse detection techniques for a complex coverage of all the characteristics of a pharmaceutical material.

Principles of work of evaporative detectors will be explained and the benefits of using alternative
(non-UV) detection techniques discussed. Data processing for non-linear detection in HPLC will be enlightened. Specific case of MS detection following normal phase liquid chromatography will be also addressed.

Important points to consider – optimization of analytical method performance characteristics and
preparation of method for formal validation will be addressed.

Real cases of unpredictable troubleshooting sessions will illustrate the material. Influence of HPLC hardware and its compatibility with HPLC methods will be pointed out.

Questions of compliance of analytical methods for pharmaceutical industry to ICH (FDA, etc.)
guidances will be briefly reviewed.

One of the most important points in analytical development for pharmaceutical industry which
should be taken into account in an industrial R&D – to develop reliable and robust methods,
friendly to a terminal user and – as simple as possible, taking into account that they are intended to be routinely run by QC analytical laboratories at a production site (“QC-able procedures”).
Presenting on an example of a comparatively simple molecule facilitates understanding and makes the workshop suitable for students and young analysts with limited experience.