recent regulatory changes and impact · 2010-03-18 · ©2010 waters corporation | company...

©2010 Waters Corporation | COMPANY CONFIDENTIAL

Recent Regulatory Changes and Impact

Erin Chambers

March 8, 2010

©2010 Waters Corporation | COMPANY CONFIDENTIAL 2

Crystal City Background

What are these Crystal City meetings??

— FDA, major pharmaceutical companies, and CRO’s get together to discuss the “Guidance for Industry for Bioanalytical Method Validation”

— Discussions around aspects of the guidance that are unclear

— Areas where more guidance is necessary

— New requirements or guidelines

How often do they occur?

— There have been 4 of them: approximate years 2000, 2003, 2006, 2008

— Advances in technology and changes in analytical practice often trigger reconsideration of the guidelines

What triggered the latest meeting?

— FDA discovered large discrepancies in calculated concentration for samples that were reanalyzed


Recent Regulatory Discussions:Incurred Sample Reanalysis (ISR)

Incurred Sample Reanalysis (ISR) discussions at recent Crystal

City Meeting, February, 2008; followed by CVG (Canada), EBF

(Europe)

— ISR will be required

— Must have SOP for ISR in place

— A % of study samples will need to be reanalyzed

— Various acceptance criteria were discussed and a consensus proposed

— AAPS Journal paper published describing one such approach to ISR

and determination of criteria3

1AAPS Journal 2007: 9 (1) Article 42AAPS Journal 2007: 9 (1) Article 113AAPS Journal 2007: 9 (3) Article 40


EEC Observations, Comments and Notes on Talks: Crystal City IV Feb. 2008, ISR

At least 5 speakers named matrix effects as one of the primary reasons for failures in ISR

Fundamental understanding that performance of QCs may not adequately mimic study samples

As of Jan. ’08, only about half of labs had ISR process currently in place

Clinical samples are more diverse than non-clinical samples

— Humans versus animals

Major causes of ISR failures consistent across many talks

— Matrix effects

— Concomitant medications

— Protein binding in patient samples; proteins vary by subject

— Metabolites converting to analytes

— Stability of analyte in specific matrix condition

— Uneven mixing/sample inhomogeneity

— Incomplete thawing

— Food effects

— Non-rugged assay


EEC Observations, Comments and Notes on Talks: Crystal City IV Feb. 2008, ISR

Senior director at Covance listed several “high risk assays”

that should definitely include ISR

— 96-well LLE assays, due to potential cross-contamination

— Glucuronide metabolite formation

— No SIL internal standard

— Assays with stability issues

— Assays with volatile analytes

— Assays with sticky analytes or analytes with adsorption or

solubility issues


Incurred Sample Reanalysis: Analytical Impact

Robustness

— Method must work equally well for spiked and incurred samples

Reproducibility

— Should pass proposed ISR acceptance criteria

— Methods must transfer successfully across labs, analysts, matrix sources, etc.

Analyte Stability

— Ensure that ISR performed within proven stability window of analyte

Selectivity— Historically heavy reliance on MS for selectivity

o ISR may require additional means of ensuring selectivity

Speed— More samples to analyze

— Need to increase productivity to accommodate


Recent Regulatory Discussions:Matrix Effects

Specific matrix effects guidelines

— Assessed by comparison in six different sources of matrix if using analog internal standard (IS)

— Variability (%CV) across 6 lots <15% 1,2

— If using a stable-labeled IS and matrix factor is “close to unity” then

determination in one lot is sufficient 2

— You must now know more about each sample, earlier

1AAPS Journal 2007: 9 (1) Article 42AAPS Journal 2007: 9 (1) Article 113AAPS Journal 2007: 9 (3) Article 40


Matrix Effects: Analytical Impact

Sensitivity

— Can reduce assay sensitivity

Selectivity

— Can cause failure to meet matrix effects guidelines

— Historically heavy reliance on MS for selectivity

o ISR and matrix effects guidelines may require additional means of ensuring selectivity

Robustness

— Divergent standard curves

— Residual matrix builds up on chromatographic column

Reproducibility

— Can cause assay variability

— Can cause ISR failures

Speed

— Longer run times may be necessary to remove co-elutions


FDA MIST Guidance

FDA MIST guidelines lines issued in Feb 2008 , require

quantification and identification of all metabolites with an

exposure >10% of active. This is dues to toxicological

effects of metabolites, potential efficacy and need to

determine metabolite PK parameters.

In a sampling of 6 drugs withdrawn from the market, 5 are known toform potentially reactive metabolites (benoxaprofen, iproniazid,nefazodone, tienilic acid, and troglitazone).

In a sampling of 15 drugs with “black box” warnings, 8 are known toform potentially reactive metabolites (dacarbazine, dantrolene,felbamate, flutamide, isoniazid, ketoconazole, tolcapone, and valproic acid).


FDA MIST Guidance

Formation of a metabolite at disproportionately higher

levels in humans than in animal model used for safety

testing

Applies to small molecule nonbiologic drug products

Recommended studies for determining safety of

metabolites

— General

— Genotoxicity

— Embryo-Fetal

— Carcinogenicity


Analytical Impact of MIST Guidelines

During the method development process it is necessary to ensure

resolution between the analyte and drug metabolites

Co-eluting metabolites can result in an over estimation of the

target compound.

Phase II metabolites such as Glucuronide and sulphates can be

cleaved in source

— Resulting aglycone can undergo same transition as target

— Chromatographic resolution is critical

These metabolites can adversely effect assay accuracy

— Cause ion suppression reducing analyte response

— Undergo thermal degradation in the source to reform the parent

compound causing over estimation of analyte concentration

Drug metabolites are chemically similar to parent compound and

may not be eliminated during SPE process


Bioanalytical Challenge:Resolution of Metabolites

Separation of metabolite critical pairs is essential for accurate quantitation and is becoming more important in order to satisfy regulatory expectations (MIST)

Ref: Donegan M,BMS, www.cosmoscience.org/archive_2008.htm

HPLC UPLC®


Further Implications of Regulatory Discussions

Up front development of the most robust, selective method

possible is more important than ever!

— Now that ISR is required and acceptance criteria suggested, matrix

effects assessment and elimination is even more important as it is a

major source of ISR failures

A little more time and money invested up front in method

development could save a lot of money (millions?) and time later

— Helps prevent failed ISR

— Failure in ISR potentially leads to repeated runs/batches/studies

o Huge loss of revenue

— Ensure selectivity of your assay by doing method development

“right” the first time

o Correct (most selective) sample prep and chromatography

What you used to do may no longer be acceptable.How much risk are you willing to take?

recent regulatory changes and impact · 2010-03-18 · ©2010 waters corporation | company...

Documents