Out of Specification Investigation Phase II & III (MHRA)

Out of Specification Investigation Phase II (Unknown Cause / No Assignable  Cause ) & Phase III

Phase II Investigation  – Unknown Cause / No Assignable  Cause

These are difficult to perform as the result can be 1 to 2 weeks after the analysis was performed and maybe weeks after the batch was manufactured. 

It is important to evaluate the test conditions carefully and determine what the boundary of samples/products/manufacturing area is.  you do not determine the boundary of the suspect results it is difficult to determine if it one or more batches impacted.

The laboratory and manufacturing investigations need to be in depth. The investigations should clearly state the hypothesis and who will be responsible for the identified tasks.

Are the organisms of an expected type, determine likely source – would it be likely to be found where it was?

Review the media – prepared in house or bought in pre-prepared, supplier history, sterilization history

Equipment/utilities used – validation, maintenance, and cleaning status. Evaluate area/environmental trends for test area and support areas.

Cleaning and maintenance of the test environment

Disinfectant used

Use appropriate root cause analysis to help brainstorm all possibilities It is likely that there may be more than one root cause

Review decisions and actions are taken in light of any new information.

Due to the variability of microbiological results don’t limit the investigation to the specific batch it should be broader to review historical results and trends

Unusual events should be included to understand potential impacts. What is the justification to perform a repeat analysis (is sample left); re-test or resample

Any identifications may need to be at DNA/RNA level (bioburden failures)

All potential sources of contamination need to be considered – process flow the issue from sample storage to the test environment.

Use scientific decisions/justifications and risk based analysis.

The investigation may include working closely with the manufacturing team

During the investigation, it is an advantage to go and look at where the contamination occurred.

Ask how relevant plant is cleaned, tested for integrity, checked for wear, checked for material suitability and maintained at the occurrence site may reveal possible causes.

Where possible talk directly to the staff involved as some information may be missed if not looked at from the chemist/ microbiologist point of view.

Look for other documentation such as deviations and engineering notifications around the area of concern (this is applicable to the laboratory as well as manufacturing).

Trending can have species drift which may also be worthy of an action limit style investigation.

Statistical analysis for microbiology can include lots of zero results so recovery rates or similar may have to be used.

If a sample is invalidated the remaining level of assurance needs to be carefully considered, is their sufficient residual information?   Corrective actions may be appropriate for more than one root cause.

Stability – OOS/OOT:

Stability OOS/OOT situations should be escalated as soon as the suspect result is found.  Follow the investigation as above for Phase I and Phase II.  For OOS Situations Regulatory agencies will require notification within a short time point of discovery due to recall potential.

If abnormal results are found at any stability interval which predicts that the test results may be OOS before the next testing interval, schedule additional testing before the next scheduled testing interval.  This will help better determine appropriate actions to be taken.

The stability OOS should link to the Product Recall procedures.

OOT

To facilitate the prompt identification of potential issues, and to ensure data quality, it is advantageous to use objective (often statistical) methods that detect potential out-of-trend (OOT) stability data quickly.

OOT alerts can be classified into three categories to help identify the appropriate depth for an investigation. OOT stability alerts can be referred to as:

–analytical,

–process control, and

–compliance alerts,

As the alert level increases from analytical to process control to compliance alert, the depth of investigation should increase.

Stability:

A compliance alert defines a case in which an OOT result suggests the potential or likelihood for OOS results to occur before the expiration date within the same stability study (or for other studies) on the same product.

The stability OOS should link to the Product Recall procedures.

Historical data are needed to identify OOT alerts.

An analytical alert is observed when a single result is aberrant but within specification limits (i.e., outside normal analytical or sampling variation and normal change over time).

If the batch is rejected there still needs to be an investigation.

To determine:

– if other batches or products are affected.

  – identification and implementation of corrective and preventative action.

Phase III Investigation

The phase 3 investigation should review the completed manufacturing investigation and combined laboratory investigation into the suspect analytical results, and/or method validation for possible causes into the results obtained.

To conclude the investigation all of the results must be evaluated.

The investigation report should contain a summary of the investigations performed; and a detailed conclusion.

For microbiological investigations ,where appropriate, use risk analysis tools to support the decisions taken and conclusions drawn.  It may not have been possible to determine the actual root cause therefore a robust most probable root cause may have to be given.

The batch quality must be determined and disposition decision taken.

Once a batch has been rejected there is no limit to further testing to determine the cause of failure, so that corrective action can be taken.

The decision to reject cannot be reversed as a result of further testing.

The impact of OOS result on other batches, ongoing stability studies, validated processes and testing procedures should be determined by Quality Control and Quality Assurance and be documented in the conclusion, along with appropriate corrective and preventive actions.

Batch Disposition

Conclusion:

If no laboratory or calculation errors are identified in Phase I and Phase II there is no scientific basis for invalidating initial OOS results in favor of passing retest results. All test results, both passing and suspect, should be reported (in all QC documents and any Certificates of Analysis) and all data has to be considered in batch release decisions.

If the investigation determines that the initial sampling method was inherently inadequate, a new accurate sampling method must be developed, documented, and reviewed and approved by the Quality Assurance responsible for the release.  Consideration should be given to other lots sampled by the same method.

An initial OOS result does not necessarily mean the subject batch fails and must be rejected. The OOS result should be investigated, and the findings of the investigation, including retest results, should be interpreted to evaluate the batch and reach a decision regarding release or rejection which should be fully documented.

In those cases where the investigation indicates an OOS result is caused by a factor affecting the batch quality (i.e., an OOS result is confirmed), the result should be used in evaluating the quality of the batch or lot. A confirmed OOS result indicates that the batch does not meet established standards or specifications and should result in the batch’s rejection and proper disposition. Other lots should be reviewed to assess impact.

For inconclusive investigations — in cases where an investigation:-

   (1) does not reveal a cause for the OOS test result and

   (2) does not confirm the OOS result

the OOS result should be given full consideration (most probable cause determined) in the batch or lot disposition decision by the certifying QP and the potential for a batch-specific variation also needs considering.

Any decision to release a batch, in spite of an initial OOS result that has not been invalidated, should come only after a full investigation has shown that the OOS result does not reflect the quality of the batch. In making such a decision, Quality Assurance/QP should always err on the side of caution

Reference :- MHRA OOS/OOT PPT

Out Of Specification Investigation Phase II (MHRA)

Out Of Specification Investigation Phase II (MHRA)

Conducted when the phase I investigations did not  reveal an assignable laboratory error.  Phase II investigations are driven by written and approved instructions against hypothesis.  Prior to further testing a manufacturing investigation should be started to determine whether there was a possible manufacturing root cause.

If not already notified the contract giver/MAH/QP (in accordance with the responsibilities in the TA) should be notified along with production and QA if a manufacturing site.

It is important when considering performing additional testing that it is performed using a predefined retesting plan to include retests performed by an analyst other than the one who performed the original test.  A second analyst performing a retest should be at least as experienced and qualified in the method as the original analyst.

If the investigation determines analyst error all analysis using the same technique performed by the concerned analyst should be reviewed.

Hypothesis/Investigative Testing

Is testing performed to help confirm or discount a possible root cause i.e what might have happened that can be tested:- for example it may include further testing regarding sample filtration, sonication /extraction; and potential equipment failures etc. Multiple hypothesis can be explored.

Re-Test

Performing the test over again using material from the original sample composite, if it has not been compromised and/or is still available. If not, a new sample will be used.

Re-sample

A new sample from the original container where possible, required in the event of insufficient material remaining from original sample composite or proven issue with original sample integrity.

Most probable cause

Scientifically justified determination that the result appears to be laboratory error.

Phase II Investigation  – Unknown Cause / No Assignable  Cause

Hypothesis Testing (Applicable to Phase Ia and Phase II):

Should be started as part of Phase Ia and continue into Phase II if no assignable cause found.

Description of the testing should be written, and then approved by QA/Contract Giver/QA equivalent prior to initiating investigational testing.  The requirements of investigational testing listed below:

The description must fully document

•The hypothesis to the test the root cause being investigated.

•What samples will be tested. 

•The exact execution of the testing.

•How the data will be evaluated

This Hypothesis testing may continue from the re-measurement of the original preparations.

Investigational testing may not be used to replace an original suspect analytical results.  It may only be used to confirm or discount a probable cause.

If no assignable cause that could explain the results can be identified during the manufacturing investigation or the assay failure investigation retesting may be considered.  Part of the investigation may involve retesting a portion of the original sample.

Retesting:

•Performed on the original sample not a different sample.

•Can be a 2nd aliquot from the same sample that was the source of the original failure.

•If insufficient quantity of the original sample remains to perform all further testing then the procedure for obtaining a resample must be discussed and agreed by QA/Contract Giver/QA equivalent.  The process of obtaining the resample should be recorded within the laboratory investigation.

•The decision to retest should be based on sound scientific judgement.  The  test plan must be approved before re testing occurs. The minimum number of retests should be documented within the procedure and be based upon scientifically sound principles.  Any statistical review  with regards to %RSD and repeatability should relate to the values obtained during method validation (accuracy, precision, and intermediate precision).  The number of retests should be statistically valid; papers have suggested 5, 7, or 9.

•The retests should be performed by a different analyst where possible.  The second analyst should be at least as experienced and qualified in the method as the original analyst.

Averaging:

•The validity of averaging depends upon the sample and its purpose. Using averages can provide more accurate results. For example, in the case of microbiological assays, the use of averages because of the innate variability of the microbiological test system.  The kinetic scan of individual wells, or endotoxin data from a number of consecutive measurements, or with HPLC consecutive replicate injections from the same preparation  (the determination is considered one test and one result), however, unexpected variation in replicate determinations should trigger investigation and documentation requirements.

•Averaging cannot be used in cases when testing is intended to measure variability within the product, such as powder blend/mixture uniformity or dosage form content uniformity.

•Reliance on averaging has the disadvantage of hiding variability among individual test results. For this reason, all individual test results should normally be reported as separate values. Where averaging of separate tests is appropriately specified by the test method, a single averaged result can be reported as the final test result. In some cases, a statistical treatment of the variability of results is reported. For example, in a test for dosage form content uniformity, the standard deviation (or relative standard deviation) is reported with the individual unit dose test results.

•In the context of additional testing performed during an OOS investigation, averaging the result (s) of the original test that prompted the investigation and additional retest or resample results obtained during the OOS investigation is not appropriate because it hides variability among the individual results. Relying on averages of such data can be particularly misleading when some of the results are OOS and others are within specifications. It is critical that the laboratory provide all individual results for evaluation and consideration by Quality Assurance (Contract Giver/QP).

All test results should conform to specifications (Note: a batch must be formulated with the intent to provide not less than 100 percent of the labelled or established amount of the active ingredient

Averaging must be specified by the test method.

•Consideration of the 95% Confidence Limits (CL 95% ) of the mean would show the variability when averaging is used.

Averaging continued: Consideration of using 95% Confidence Limits (CL 95% ) of the mean would show the variability when averaging is used.

The confidence interval is calculated from the formula:

CL= sample mean ± t 95% sample standard deviation/ √ n

–Where t is a value obtained from tables

–Where n is the sample size

–Table:

n t 95%
2 12.71
3 4.30
4 3.18
5 2.78
6 2.57
7 2.45
10 2.26
20 2.09
120 1.98
1.96

Re-sampling:

Should rarely occur, If insufficient quantity of the original sample remains to perform all further testing then the procedure for obtaining a resample must be discussed and agreed by QA/Contract Giver/QA equivalent.  The process of obtaining the resample should be recorded within the laboratory investigation. Re-sampling should be performed by the same qualified methods that were used for the initial sample. However, if the investigation determines that the initial sampling method was in error, a new accurate sampling method shall be developed, qualified and documented. It involves the collecting a new sample from the batch. Will occur when the original sample was not truly representative of the batch or there was a documented/traceable lab error in its preparation. Evidence indicates that the sample is compromised or invalid. Sound scientific justification must be employed if re-sampling is to occur.

Outlier test:

An outlier may result from a deviation from prescribed test methods, or it may be the result of variability in the sample. It should never be assumed that the reason for an outlier is error in the testing procedure, rather than inherent variability in the sample being tested. Statistical analysis for Outlier test results can be as part of the investigation and analysis.  However for validated chemical tests with relatively small variance and that the sample was considered homogeneous it cannot be used to justify the rejection of data.

• While OOS guidance is not directly intended for bioassay analysis, it can be used as a starting point for the investigation. Compendia such as the BP; PhEur and USP, provide guidance on outliers for these types of analysis

Reference :- MHRA OOS & OOT Investigation PPT.

Out Of Spesification Phase Ia & Ib ( MHRA)

Out Of Specification Investigation Phase Ia & Phase Ib (MHRA)

Out Of Specification Investigation Phase Ia & Phase Ib (MHRA)

Phase Ia Investigation

Definition:

Out of Specification Investigation Phase la investigation is to determine whether there has been a clear obvious errors due to external circumstances such as power failure or those that the analyst has detected prior to generating data such as spilling sample that will negate the requirement of a Phase Ib investigation.

For microbiological analysis this may be after the analysis has been completed and reviewed during reading of the samples.

It is expected that these issues are trended even if a laboratory investigation lb or ll was not raised.

Phase la Investigation – Obvious Error

Examples

Calculation error – 

analyst and supervisor to review, both initial and date correction.

Power outage –

analyst and supervisor document the event, annotate “power failure; analysis to be repeated” on all associated analytical documentation.

Equipment failure  –

analyst and supervisor document the event, annotate “equipment failure; analysis to be repeated” cross reference the maintenance record.

Testing errors –

for example, spilling of the sample solution, incomplete transfer of a sample; the analyst must document immediately.

for microbiology it could be growth on a plate not in the test sample area, negative or positive controls failing.

Incorrect Instrument Parameters –

for example setting the detector at the wrong wavelength, analyst and supervisor document the event, annotate “incorrect instrument parameter”; analysis to be repeated” on all associated analytical documentation .

If no error was noted, and none of the above conditions were met Phase Ib investigation must take place.

Phase Ib Investigation

Specification –

A specification is defined as a list of tests, references to analytical procedures, and appropriate acceptance criteria which are numerical limits, ranges, or other criteria for the tests described.  It establishes the set of criteria to which a drug substance, drug product or materials at other stages of its manufacture should conform to be considered acceptable for its intended use.  “Conformance to specification” means that the drug substance and drug product, when tested according to the listed analytical procedures, will meet the acceptance criteria. Specifications are critical quality standards that are proposed and justified by the manufacturer and approved by regulatory authorities as conditions of approval.

Regulatory Approved Specification

Specifications for release testing.  If no release specifications have been established then the internal specification becomes the release specification.

Acceptance Criteria –

Numerical limits, ranges, or other suitable measures for acceptance of the results of analytical procedures which the drug substance or drug product or materials at other stages of their manufacture should meet.

Internal Specification –

Are also action limits within regulatory specifications.

Phase Ib Investigation – Definitions

Assignable Cause –

An identified reason for obtaining an OOS or aberrant/anomalous result.

No Assignable Cause  –

  When no reason could be identified.

Invalidated test –

  A test is considered invalid when the investigation has determined the   assignable cause. •

Reportable result –

Is the final analytical result. This result is appropriately defined in the written approved test method and derived from one full execution of that method, starting from the original sample.

Warning Level or Trend excursions

If two or more consecutive samples exceed warning (alert), or if an increasing level of counts, or same organisms identified, over a short period was identified consideration should be given to treat the results as action level excursions.

Hypothesis/Investigative Testing

  Is testing performed to help confirm or discount a possible root cause i.e what might have happened that can be tested:- for example it may include further testing regarding sample filtration, sonication /extraction; and potential equipment failures etc. Multiple hypothesis can be explored.

Investigation by Analyst and Supervisor

Phase Ib Investigation – Initial Investigation conducted by the analyst and supervisor using the Laboratory Investigation Checklist

Contact Production/Contract Giver/QP/MAH as appropriate

For microbiological analysis where possible once a suspect result has been identified ensure all items related to the test failure are retained such as other environmental plates, dilutions, ampoules/vials of product, temperature data, auto-pipettes, reagents – growth media.  No implicated test environmental plates should be destroyed until the investigation has been completed.

The Analyst and Supervisor investigation should be restricted to data / equipment / analysis review only

On completion of the Analyst and Supervisor investigation re-measurement can start once the hypothesis plan is documented and is only to support the investigation testing.

This initial hypothesis testing can include the original working stock solutions but should not include another preparation from the original sample (see: re-testing)

The checklist may not be all-inclusive, but should be a good guideline to cover the pertinent areas that need to be covered in any laboratory investigation:-

-Correct test methodology followed e.g.. Version number.

-Correct sample(s) taken/tested (check labels was it taken from a correct place).

Sample Integrity maintained, correct container and chain of custody (was there an unusual event or problem).

How were sample containers stored prior to use

Correct sampling procedure followed e.g. version number

Assessment of the possibility that the sample contamination has occurred during the testing/ re-testing procedure (e.g. sample left open to the air or unattended).

All equipment used in the testing is within calibration date.

-Review equipment log books. -Appropriate standards used in the analysis. -Standard(s) and/or control(s) performed as expected.

System suitability conditions met (those before analysis and during analysis).

-Correct and clean glassware used.

-Correct pipette / volumetric flasks volumes used. -Correct specification applied.

-Media/Reagents prepared according to procedure.

•Items were within expiry date

•A visual examination (solid and solution) reveals normal or abnormal appearance

Data acceptance criteria met

-The analyst is trained on the method.

Interview analyst to assess knowledge of the correct procedure.

Examination of the raw data, including chromatograms and spectra; any anomalous or suspect peaks or data.

Any previous issues with this assay.

-Other potentially interfering testing/activities occurring at the time of the test.

-Any issues with environmental temperature/humidity within the area whilst the test was conducted.

-Review of other data for other batches performed within the same analysis set.

Consideration of any other OOS results obtained on the batch of material under test.

Assessment of method validation.

Additional considerations for microbiological analysis:

-Are the isolates located as expected

on glove dab marks, SAS ‘dimples’, filter membrane, etc.

-Was the sample media  integral

i.e. no cracks in plates.

Was there contamination present in other tests (or related tests) performed at the same time, including environmental controls.

-Were negative and positive controls satisfactory.

Were the correct media/reagents used?

Were the samples integral (not leaking)

Were the samples stored correctly (refrigerated)

Were the samples held for the correct time before used for the test?

Was the media/reagent stored correctly before use

Were the incubation conditions satisfactory?

Take photographs to document the samples at the time of reading (include plates, gram stains and anything else that may be relevant).

If still investigation is not closed then investigation should go in Phase II

Reference:- MHRA OOS & OOT PPT.

Out of Specification Investigation Phase II (MHRA).

Out Of Specification & Out Of Trend Investigation (MHRA).

Out of Specification &Out of Trend Investigations (MHRA)

Flow chart of OOS & OOT Investigations


Out of Specification &Out of Trend Investigations (MHRA)

Laboratory Analysis

Investigations of “Out of Specification (OOS) / Out of Trend (OOT)/ Atypical results” have to be done in cases of:

  • Batch release testing and testing of starting materials.
    • In-Process Control testing: if data is used for batch calculations/decisions and if in a dossier and on Certificates of Analysis.
    • Stability studies on marketed batches of finished products and or active pharmaceutical ingredients, on-going / follow up stability (no stress tests)
    • Previous released batch used as reference sample in an OOS investigation showing OOS or suspect results.
    • Batches for clinical trials.

All solutions and reagents should be retained until all data has been second person verified as being within the defined acceptance criteria.

Pharmacopoeia have specific criteria for additional analyses of specific tests (i.e. dissolution level specification for S1, S2 & S3 testing; Uniformity of dosage units specification for testing of 20 additional units; Sterility Testing). 

However, if the sample test criteria are usually the first level of testing and a sample has to be tested to the next level this should be investigated as it is not following the normal trend.

The OOS process is not applicable for In-process testing while trying to achieve a  manufacturing process end-point i.e. adjustment of the manufacturing process. (e.g. pH, viscosity), and for studies conducted at variable parameters to check the impact of drift (e.g. process validation at variable parameters).

     Out-of-Specification (OOS) Result –

  • Test result that does not comply with the pre-determined acceptance criteria (i.e. for example, filed applications, drug master files, approved marketing submissions, or official compendia or internal acceptance criteria). 
    • Test results that fall outside of established acceptance criteria which have been established in official compendia and/or by company documentation (i.e., Raw Material Specifications, In-Process/Final Product Testing, etc.).

Out of Trend (OOT) Result –

  • Is generally a stability result that does not follow the expected trend, either in comparison with other stability batches or with respect to previous results collected during a stability study. However the trends of starting materials and in-process samples may also yield out of trend data.
    • The result is not necessarily OOS but does not look like a typical data point.
    • Should be considered for environmental trend analysis such as for viable and non viable data (action limit or warning limit trends)

Atypical / Aberrant / Anomalous Result –

  • Results that are still within specification but are unexpected, questionable, irregular, deviant or abnormal.  Examples would be chromatograms that show unexpected peaks, unexpected results for stability test point, etc.

Reference :- This is a guidance document that details MHRA expectations

How to Investigate Out Of Specification(OOS) Test Results….??? ( USFDA Phase -II)

How to Investigate Out Of Specification(OOS) Test Results….??? ( USFDA Phase -II)

Out Of Specification( OOS ) :-  The all test results which goes outside the specification or acceptance criteria established in Drug Dossiers, Drug Master files, Its official Pharmacopeias, Or the manufacturer comes Under Out of Specification( OOS ).

We have seen in last post about Phase -I Investigation of Out of Specification (OOS) Test Results. Now we will see Phase -II of Investigation of Out of Specification (OOS) Test Results.

 INVESTIGATING OOS TEST RESULTS — PHASE II: FULL-SCALE OOS INVESTIGATION

 

When the initial assessment does not determine that laboratory error caused the OOS result and testing results appear to be accurate, a full-scale OOS investigation using a predefined procedure should be conducted. This investigation may consist of a production process review and/or additional laboratory work. The objective of such an investigation should be to identify the root cause of the OOS result and take appropriate corrective and preventative action.7 A full-scale investigation should include a review of production and sampling procedures, and will often include additional laboratory testing. Such investigations should be given the highest priority. Among the elements of this phase is evaluation of the impact of OOS result(s) on already distributed batches.

 

  1. Review of Production

The investigation should be conducted by the QCU and should involve all other departments that could be implicated, including manufacturing, process development, maintenance, and engineering. In cases where manufacturing occurs off-site (i.e., performed by a contract manufacturer or at multiple manufacturing sites), all sites potentially involved should be included in the investigation. Other potential problems should be identified and investigated

The records and documentation of the manufacturing process should be fully reviewed to determine the possible cause of the OOS result(s). A full-scale OOS investigation should consist of a timely, thorough, and well-documented review. A written record of the review should include the following information.

 

  1. A clear statement of the reason for the investigation.
  2. A summary of the aspects of the manufacturing process that may have caused the problem.
  3. The results of a documentation review, with the assignment of actual or probable cause.
  4. The results of a review made to determine if the problem has occurred previously.
  5. A description of corrective actions taken.

If this part of the OOS investigation confirms the OOS result and is successful in identifying its root cause, the OOS investigation may be terminated and the product rejected. However, a failure investigation that extends to other batches or products that may have been associated with the specific failure must be completed (§ 211.192). If any material was reprocessed after additional testing, the investigation should include comments and the signatures of appropriate production and quality control personnel.

OOS results may indicate a flaw in product or process design. For example, a lack of robustness in product formulation, inadequate raw material characterization or control, substantial variation introduced by one or more unit operations of the manufacturing process, or a combination of these factors can be the cause of inconsistent product quality. In such cases, it is essential that redesign of the product or process be undertaken to ensure reproducible product quality.

  1. Additional Laboratory

 

Testing A full-scale OOS investigation may include additional laboratory testing. A number of practices are used during the laboratory phase of an investigation. These include (1) retesting a portion of the original sample and (2) resampling.

  1. Retesting

Part of the investigation may involve retesting of a portion of the original sample. The sample used for the retesting should be taken from the same homogeneous material that was originally collected from the lot, tested, and yielded the OOS results. For a liquid, it may be from the original unit liquid product or composite of the liquid product; for a solid, it may be an additional weighing from the same sample composite prepared for the original test.

Situations where retesting is indicated include investigating testing instrument malfunctions or to identify a possible sample handling problem, for example, a suspected dilution error. Decisions to retest should be based on the objectives of the testing and sound scientific judgment. It is often important for the predefined retesting plan to include retests performed by an analyst other than the one who performed the original test. A second analyst performing a retest should be at least as experienced and qualified in the method as the original analyst.

The CGMP regulations require the establishment of specifications, standards, sampling plans, test procedures, and other laboratory control mechanisms (§ 211.160).

FDA inspections have revealed that some firms use a strategy of repeated testing until a passing result is obtained, then disregarding the OOS results without scientific justification. This practice of “testing into compliance” is unscientific and objectionable under CGMPs. The maximum number of retests to be performed on a sample should be specified in advance in a written standard operating procedure (SOP). The number may vary depending upon the variability of the particular test method employed, but should be based on scientifically sound principles. The number of retests should not be adjusted depending on the results obtained. The firm’s predetermined retesting procedures should contain a point at which the additional testing ends and the batch is evaluated.

If the results are unsatisfactory at this point, the batch is suspect and must be rejected or held pending further investigation (§ 211.165(f)). Any deviation from this SOP should be rare and done in accordance with § 211.160(a), which states that any deviations from written specifications, sampling plans, test procedures, or other laboratory control mechanisms shall be recorded and justified. In such cases, before starting additional retesting, a protocol should be prepared (subject to approval by the QCU) that describes the additional testing to be performed and specifies the scientific and/or technical handling of the data.

In the case of a clearly identified laboratory error, the retest results would substitute for the original test result. All original data should be retained, however, and an explanation recorded. This record should be initialed and dated by the involved persons and include a discussion of the error and supervisory comments. (See section III of this guidance for more details on a laboratory investigation.)

If no laboratory or calculation errors are identified in the first test, there is no scientific basis for invalidating initial OOS results in favor of passing retest results. All test results, both passing and suspect, should be reported  and considered in batch release decisions.

 

  1. Resampling

 

While retesting refers to analysis of the original, homogenous sample material, resampling involves analyzing a specimen from any additional units collected as part of the original sampling procedure or from a new sample collected from the batch, should that be necessary

The original sample from a batch should be sufficiently large to accommodate additional testing in the event an OOS result is obtained.

When all data have been evaluated, an investigation might conclude that the original sample was prepared improperly and was therefore not representative of the batch quality (§ 211.160(b)(3)). Improper sample preparation might be indicated, for example, by widely varied results obtained from several aliquots of an original composite (after determining there was no error in the performance of the analysis). Resampling should be performed by the same qualified, validated methods that were used for the initial sample.

 

  1. Reporting Testing Results

 

Practices used in reporting and interpretation of test results include (1) averaging and (2) outlier tests.

  1. Averaging

There are both appropriate and inappropriate uses of averaging test data during original testing and during an OOS investigation:

  1. Appropriate uses

Averaging data can be a valid approach, but its use depends upon the sample and its purpose. For example, in an optical rotation test, several discrete measurements are averaged to determine the optical rotation for a sample, and this average is reported as the test result. If the sample can be assumed to be homogeneous, (i.e., an individual sample preparation designed to be homogenous), using averages can provide a more accurate result. In the case of microbiological assays, the U.S. Pharmacopeia (USP) prefers the use of averages because of the innate variability of the biological test system.

In some cases, a series of complete tests (full run-throughs of the test procedure), such as assays, are part of the test method. It may be appropriate to specify in the test method that the average of these multiple assays is considered one test and represents one reportable result. In this case, limits on acceptable variability among the individual assay results should be based on the known variability of the method and should also be specified in the test methodology. A set of assay results not meeting these limits should not be used.

These appropriate uses of averaging test data should be used during an OOS investigation only if they were used during the original testing that produced the OOS result

 

  1. Inappropriate uses

 

Reliance on averaging has the disadvantage of hiding variability among individual test results. For this reason, all individual test results should normally be reported as separate values. Where averaging of separate tests is appropriately specified by the test method, a single averaged result can be reported as the final test result. In some cases, a statistical treatment of the variability of results is reported. For example, in a test for dosage form content uniformity, the standard deviation (or relative standard deviation) is reported with the individual unit dose test results.

Averaging can also conceal variations in different portions of a batch, or within a sample. For example, the use of averages is inappropriate when performing powder blend/mixture uniformity or dosage form content uniformity determinations. In these cases, testing is intended to measure variability within the product, and individual results provide the information for such an evaluation.

In the context of additional testing performed during an OOS investigation, averaging the result(s) of the original test that prompted the investigation and additional retest or resample results obtained during the OOS investigation is not appropriate because it hides variability among the individual results. Relying on averages of such data can be particularly misleading when some of the results are OOS and others are within specifications. It is critical that the laboratory provide all individual results for evaluation and consideration by the QCU, which is responsible for approving or rejecting, e.g., drug products, in-process materials (§ 211.22)

For example, in an assay of a finished drug with a specification of 90 to 110 percent, an initial OOS result of 89 percent followed by additional retest results of 90 percent and 91 percent would produce an average of 90 percent. While this average would meet specifications,11 the additional test results also tend to confirm the original OOS result. However, in another situation with the same specifications, an initial OOS result of 80 percent followed by additional test results of 85 percent and 105 percent would also produce an average of 90 percent, but present a much different picture. These results do not confirm the original OOS result but show high variability and may not be reliable. In both examples, the individual results, not the average, should be used to evaluate the quality of the product.

 

  1. Outlier Tests

 

The CGMP regulations require that statistically valid quality control criteria include appropriate acceptance and/or rejection levels (§ 211.165(d)). On rare occasions, a value may be obtained that is markedly different from the others in a series obtained using a validated method. Such a value may qualify as a statistical outlier. An outlier may result from a deviation from prescribed test methods, or it may be the result of variability in the sample. It should never be assumed that the reason for an outlier is error in the testing procedure, rather than inherent variability in the sample being tested.

Outlier testing is a statistical procedure for identifying from an array those data that are extreme. The possible use of outlier tests should be determined in advance. This should be written into SOPs for data interpretation and be well documented. The SOPs should include the specific outlier test to be applied with relevant parameters specified in advance. The SOPs should specify the minimum number of results required to obtain a statistically significant assessment from the specified outlier test.

For biological assays having a high variability, an outlier test may be an appropriate statistical analysis to identify those results that are statistically extreme observations. The USP describes outlier tests in the general chapter on Design and Analysis of Biological Assays <111>.  In these cases, the outlier observation is omitted from calculations. The USP also states that “arbitrary rejection or retention of an apparently aberrant response can be a serious source of bias… the rejection of observations solely on the basis of their relative magnitudes is a procedure to be used sparingly” (USP <111>).

For validated chemical tests with relatively small variance, and if the sample being tested can be considered homogeneous (for example, an assay of a composite of a dosage form drug to determine strength), an outlier test is only a statistical analysis of the data obtained from testing and retesting. It will not identify the cause of an extreme observation and, therefore, should not be used to invalidate the suspect result. Occasionally, an outlier test may be of some value in estimating the probability that the OOS result is discordant from a data set, and this information can be used in an auxiliary fashion, along with all other data from the investigation, to evaluate the significance of the result.

Outlier tests have no applicability in cases where the variability in the product is what is being assessed, such as for content uniformity, dissolution, or release rate determinations. In these applications, a value perceived to be an outlier may in fact be an accurate result of a nonuniform product.

When using these practices during the additional testing performed in an OOS investigation, the laboratory will obtain multiple results. It is again critical for the laboratory to provide all test results for evaluation and consideration by the QCU in its final disposition decision. In addition, when investigation by a contract laboratory does not determine an assignable cause, all test results should be reported to the customer on the certificate of analysis

 

  1. CONCLUDING THE INVESTIGATION

To conclude the investigation, the results should be evaluated, the batch quality should be determined, and a release decision should be made by the QCU. The SOPs should be followed in arriving at this point. Once a batch has been rejected, there is no limit to further testing to determine the cause of the failure so that a corrective action can be taken.

 

  1. Interpretation of Investigation Results

The QCU is responsible for interpreting the results of the investigation. An initial OOS result does not necessarily mean the subject batch fails and must be rejected. The OOS result should be investigated, and the findings of the investigation, including retest results, should be interpreted to evaluate the batch and reach a decision regarding release or rejection (§ 211.165).

In those instances where an investigation has revealed a cause, and the suspect result is invalidated, the result should not be used to evaluate the quality of the batch or lot. Invalidation of a discrete test result may be done only upon the observation and documentation of a test event that can reasonably be determined to have caused the OOS result.

In those cases where the investigation indicates an OOS result is caused by a factor affecting the batch quality (i.e., an OOS result is confirmed), the result should be used in evaluating the quality of the batch or lot. A confirmed OOS result indicates that the batch does not meet established standards or specifications and should result in the batch’s rejection, in accordance with § 211.165(f), and proper disposition. For inconclusive investigations — in cases where an investigation (1) does not reveal a cause for the OOS test result and (2) does not confirm the OOS result — the OOS result should be given full consideration in the batch or lot disposition decision.

In the first case (OOS confirmed), the investigation changes from an OOS investigation into a batch failure investigation, which must be extended to other batches or products that may have been associated with the specific failure (§ 211.192). In the second case (inconclusive), the QCU might still ultimately decide to release the batch. For example, a firm might consider release of the product under the following scenario:

A product has an acceptable composite assay range of 90.0 to 110.0 percent. The initial (OOS) assay result is 89.5 percent. Subsequent sample preparations from the original sample yield the following retest results: 99.0, 98.9, 99.0, 99.1, 98.8, 99.1, and 99.0 percent. A comprehensive laboratory investigation (Phase 1) fails to reveal any laboratory error. Review of events during production of the batch reveals no aberrations or indication of unusual process variation. Review of the manufacturing process and product history demonstrates that the process is robust. The seven passing retest results are all well within the known limits of variability of the method used. Batch results from in-process monitoring, content uniformity, dissolution, and other tests are consistent with the passing retest results. After a thorough investigation, a firm’s QCU might conclude that the initial OOS result did not reflect the true quality of the batch.

It is noteworthy in this scenario that the original, thorough laboratory investigation failed to find any assignable cause. However, if subsequent investigation nonetheless concludes that the source of the OOS result was a cause unrelated to the manufacturing process, in response to this atypical failure to detect the laboratory deviation, it is essential that the investigation include appropriate follow-up and scrutiny to prevent recurrence of the laboratory error(s) that could have led to the OOS result.

As the above example illustrates, any decision to release a batch, in spite of an initial OOS result that has not been invalidated, should come only after a full investigation has shown that the OOS result does not reflect the quality of the batch. In making such a decision, the QCU should always err on the side of caution.

  1. Cautions

In cases where a series of assay results (to produce a single reportable result) are required by the test procedure and some of the individual results are OOS, some are within specification, and all are within the known variability of the method, the passing results are no more likely to represent the true value for the sample than the OOS results. For this reason, a firm should err on the side of caution and treat the reportable average of these values as an OOS result, even if that average is within specification. This approach is consistent with the principle outlined in the USP General Notices that an official article shall comply with the compendial standard any time a compendial test is applied.15 Thus, every individual application of the official test should be expected to produce a result that meets specifications.

An assay result that is low, but within specifications, should also raise a concern. One cause of the result could be that the batch was not formulated properly. Batches must be formulated with the intent to provide not less than 100 percent of the labeled or established amount of active ingredient (§ 211.101 (a)). This would also be a situation where the analytical result meets specifications, but caution should be used in the release or reject decision.

As with all analytical testing conducted to evaluate the quality of a drug, all records pertaining to the OOS test result should be retained. Records must be kept of complete data derived from all tests performed to ensure compliance with established specifications and standards (§ 211.194).

  1. Field Alert Reports

For those products that are the subject of approved full and abbreviated new drug applications, regulations require submitting within 3 working days a field alert report (FAR) of information concerning any failure of a distributed batch to meet any of the specifications established in an application (21 CFR 314.81(b)(1)(ii)). OOS test results on these products are considered to be one kind of “information concerning any failure” described in this regulation. Unless the OOS result on the distributed batch is found to be invalid within 3 days, an initial FAR should be submitted. A follow-up FAR should be submitted when the OOS investigation is completed.

How to Investigate Out Of Specification(OOS) Test Results….???( USFDA Phase -I)

How to Investigate Out Of Specification(OOS) Test Results….??? ( USFDA Phase -I)

Out Of Specification(OOS) :-  The all test results which goes outside the specification or acceptance criteria established in Drug Dossiers, Drug Master files, Its official Pharmacopeias, Or the manufacturer comes Under Out of Specification(OOS).

 

What USFDA guideline says about Investigation of Out of Specification.?

 

The term OOS results includes all test results that fall outside the specifications or acceptance criteria established in drug applications, drug master files (DMFs), official compendia, or by the manufacturer. The term also applies to all in-process laboratory tests that are outside of established specifications.

This guidance applies to chemistry-based laboratory testing of drugs regulated by CDER. It is directed toward traditional drug testing and release methods. These laboratory tests are performed on active pharmaceutical ingredients, excipients and other components, in-process materials, and finished drug products3 to the extent that current good manufacturing practice (CGMP) regulations (21 CFR parts 210 and 211) and the Federal Food, Drug, and Cosmetic Act (the Act) (section 501(a)(2)(B)) apply. The principles in this guidance also apply to in-house testing of drug product components that are purchased by a firm. This guidance can also be used by contract firms performing production and/or laboratory testing responsibilities. Specifically, the guidance discusses how to investigate OOS test results, including the responsibilities of laboratory personnel, the laboratory phase of the investigation, additional testing that may be necessary, when to expand the investigation outside the laboratory, and the final evaluation of all test results.

IDENTIFYING AND ASSESSING OOS TEST RESULTS — PHASE I: LABORATORY INVESTIGATION FDA

 

Regulations require that an investigation be conducted whenever an OOS test result is obtained (§ 211.192).6 The purpose of the investigation is to determine the cause of the OOS result. The source of the OOS result should be identified either as an aberration of the measurement process or an aberration of the manufacturing process. Even if a batch is rejected based on an OOS result, the investigation is necessary to determine if the result is associated with other batches of the same drug product or other products. Batch rejection does not negate the need to perform the investigation. The regulations require that a written record of the investigation be made, including the conclusions and follow-up (§ 211.192). To be meaningful, the investigation should be thorough, timely, unbiased, well-documented, and scientifically sound. The first phase of such an investigation should include an initial assessment of the accuracy of the laboratory’s data. Whenever possible, this should be done before test preparations (including the composite or the homogenous source of the aliquot tested) are discarded. This way, hypotheses regarding laboratory error or instrument malfunctions can be tested using the same test preparations. If this initial assessment indicates that no meaningful errors were made in the analytical method used to arrive at the data, a full-scale OOS investigation should be conducted. For contract laboratories, the laboratory should convey its data, findings, and supporting documentation to the manufacturing firm’s quality control unit (QCU), who should then initiate the full-scale OOS investigation.

 

  1. Responsibility of the Analyst

 

The first responsibility for achieving accurate laboratory testing results lies with the analyst who is performing the test. The analyst should be aware of potential problems that could occur during the testing process and should watch for problems that could create inaccurate results.

In accordance with the CGMP regulations in § 211.160 (b)(4), the analyst should ensure that only those instruments meeting established performance specifications are used and that all instruments are properly calibrated.

Certain analytical methods have system suitability requirements, and systems not meeting these requirements should not be used. For example, in chromatographic systems, reference standard solutions may be injected at intervals throughout chromatographic runs to measure drift, noise, and repeatability. If reference standard responses indicate that the system is not functioning properly, all of the data collected during the suspect time period should be properly identified and should not be used. The cause of the malfunction should be identified and, if possible, corrected before a decision is made whether to use any data prior to the suspect period.

Analysts should check the data for compliance with test specifications before discarding test preparations or standard preparations. When unexpected results are obtained and no obvious explanation exists, test preparations should be retained, if stable, and the analyst should inform the supervisor. An assessment of the accuracy of the results should be started immediately.

If errors are obvious, such as the spilling of a sample solution or the incomplete transfer of a sample composite, the analyst should immediately document what happened.

Analysts should not knowingly continue an analysis they expect to invalidate at a later time for an assignable cause (i.e., analyses should not be completed for the sole purpose of seeing what results can be obtained when obvious errors are known).

 

  1. Responsibilities of the Laboratory Supervisor

Once an OOS result has been identified, the supervisor’s assessment should be objective and timely. There should be no preconceived assumptions as to the cause of the OOS result. Data should be assessed promptly to ascertain if the results might be attributed to laboratory error, or whether the results could indicate problems in the manufacturing process. An immediate assessment could include re-examination of the actual solutions, test units, and glassware used in the original measurements and preparations, which might provide more credibility for laboratory error hypotheses.

The following steps should be taken as part of the supervisor’s assessment:

  1. Discuss the test method with the analyst; confirm analyst knowledge of and performance of the correct procedure.

  2. Examine the raw data obtained in the analysis, including chromatograms and spectra, and identify anomalous or suspect information.

  3. Verify that the calculations used to convert raw data values into a final test result are scientifically sound, appropriate, and correct; also determine if unauthorized or unvalidated changes have been made to automated calculation methods.

  4. Confirm the performance of the instruments.

  5. Determine that appropriate reference standards, solvents, reagents, and other solutions were used and that they met quality control specifications.

  6. Evaluate the performance of the test method to ensure that it is performing according to the standard expected based on method validation data and historical data.

  7. Fully document and preserve records of this laboratory assessment.

The assignment of a cause for OOS results will be greatly facilitated if the retained sample preparations are examined promptly. Hypotheses regarding what might have happened (e.g. dilution error, instrument malfunction) should be tested. Examination of the retained solutions should be performed as part of the laboratory investigation.

 

Examples:

  • Solutions can be re-injected as part of an investigation where a transient equipment malfunction is suspected. Such hypotheses are difficult to prove. However, reinjections can provide strong evidence that the problem should be attributed to the instrument, rather than the sample or its preparation.

  • For release rate testing of certain specialized dosage form drugs that are not destroyed during testing, where possible, examination of the original dosage unit tested might determine whether it was damaged during laboratory handling in a way that affected its performance. Such damage would provide evidence to invalidate the OOS test result, and a retest would be indicated.

  • Further extraction of a dosage unit, where possible, can be performed to determine whether it was fully extracted during the original analysis. Incomplete extraction could invalidate the test results and should lead to questions regarding validation of the test method.

It is important that each step in the investigation be fully documented. Laboratory management should ascertain not only the reliability of the individual value obtained, but also the significance these OOS results represent to the laboratory quality assurance program. Laboratory management should be especially alert to developing trends. As part of an effective quality system, a firm’s upper management should appropriately monitor these trends and ensure that any problematic areas are addressed.

Laboratory error should be relatively rare. Frequent errors suggest a problem that might be due to inadequate training of analysts, poorly maintained or improperly calibrated equipment, or careless work. Whenever laboratory error is identified, the firm should determine the source of that error and take corrective action to prevent recurrence. To ensure full compliance with the CGMP regulations, the manufacturer also should maintain adequate documentation of the corrective action.

In summary, when clear evidence of laboratory error exists, laboratory testing results should be invalidated. When evidence of laboratory error remains unclear, a full-scale OOS investigation should be conducted by the manufacturing firm to determine what caused the unexpected results. It should not be assumed that OOS test results are attributable to analytical error without performing and documenting an investigation. Both the initial laboratory assessment and the following OOS investigation should be documented fully.

Reference :-

Guidance for Industry

Investigating Out-of-Specification (OOS)
Test Results for
Pharmaceutical Production

( USFDA)