requirements of regulatory authorities and that the final product meets regulatory approval.

4. Accountability

The Manufacturing Manager is accountable for ensuring that the re-evaluation of stability failures is conducted according to this SOP. The overall compliance with this SOP is overseen by the Quality Assurance (QA) Manager.

5. Procedure

5.1. Identification of Stability Failures

1. Stability failures can be identified during regular stability testing at predefined intervals, including long-term, accelerated, or intermediate testing conditions. Failures may include changes in product appearance, chemical composition, performance (e.g., spray rate, valve function), or physical properties (e.g., viscosity, pH).
2. Once a stability failure is observed, it must be documented in the Stability Failure Log (Annexure-1). The log should include the batch number, test conditions, observed failure, and date of the failure identification.
3. The product must be reviewed to determine if the failure is isolated to a specific batch or if it is a recurring issue across multiple batches.

5.2. Investigation of Stability Failures

1. The Stability Testing Team should investigate the root cause of the failure. This investigation should include:
   • Reviewing the formulation and manufacturing process for potential issues (e.g., incorrect raw material usage, formulation instability, improper packaging).
   • Checking the storage conditions and handling of the samples during stability testing to ensure they were tested under correct conditions.
   • Examining the stability chamber conditions, including calibration of temperature and humidity controls, to ensure proper testing conditions were maintained.
   • Determining if external factors (e.g., transportation, environmental exposure) could have contributed to the failure.
2. The team should conduct further tests on the failed batch if necessary, using alternative or modified test methods (e.g., additional chemical tests or accelerated stability testing) to verify the cause of the failure.
3. Any findings from the investigation should be documented in the Investigation Report (Annexure-2), which should include the suspected root cause and a proposed action plan for corrective measures.

5.3. Corrective Actions

1. If the root cause of the failure is identified, corrective actions should be implemented to address the issue. These actions may include:
   • Reformulating the product to address instability issues
   • Modifying the manufacturing process or improving raw material quality
   • Changing the packaging material or design to improve protection from light, air, or moisture
   • Improving stability testing procedures or equipment to avoid similar issues in future testing
2. Corrective actions should be documented in the Corrective Action Log (Annexure-3) and should include the specific steps taken, the person responsible for each action, and the completion date.
3. The QA team should review and approve the corrective actions to ensure they are appropriate and effective.

5.4. Re-testing of Corrected Batches

1. If the corrective actions are implemented, the affected batch or subsequent batches should be re-tested under the same stability conditions to confirm that the changes have resolved the stability issues.
2. The re-testing results should be documented in the Stability Re-test Log (Annexure-4) and compared with previous stability data to verify the product’s stability performance after corrective actions.
3. Once the re-testing confirms that the product is stable, the results should be reviewed and approved by the QA team before the product is released for further processing or distribution.

5.5. Documentation and Reporting

1. All documentation related to the re-evaluation of stability failures should be stored securely for regulatory review. The following documents must be maintained:
   • Stability Failure Log (Annexure-1)
   • Investigation Report (Annexure-2)
   • Corrective Action Log (Annexure-3)
   • Stability Re-test Log (Annexure-4)
2. All documentation should be signed and dated by the responsible personnel and reviewed periodically by the QA team to ensure compliance with internal procedures and regulatory requirements.

6. Abbreviations

• GMP: Good Manufacturing Practice
• QA: Quality Assurance
• SOP: Standard Operating Procedure
• RH: Relative Humidity
• CFR: Code of Federal Regulations
• CAPA: Corrective and Preventive Action

7. Documents

1. Stability Failure Log (Annexure-1)
2. Investigation Report (Annexure-2)
3. Corrective Action Log (Annexure-3)
4. Stability Re-test Log (Annexure-4)

8. References

This SOP is based on the following regulatory guidelines and industry standards:

• Good Manufacturing Practice (GMP) Guidelines
• FDA Code of Federal Regulations (CFR) Title 21, Part 211
• International Council for Harmonisation (ICH) Guidelines

9. SOP Version

Version: 2.0

10. Approval Section

	Prepared By	Checked By	Approved By
Signature
Date
Name
Designation
Department

11. Annexures

Annexure-1: Stability Failure Log

Batch Number	Test Date	Failure Type	Test Conditions	Failure Description	Operator Name
Batch-001	10/02/2025	Chemical instability	25°C/60% RH	Discoloration observed	Rajesh Patel

Annexure-2: Investigation Report

Investigation ID	Investigation Date	Root Cause	Corrective Action	Investigator Name
INV-54321	12/02/2025	Incorrect formulation component	Reformulation with new component	Rajesh Patel

Annexure-3: Corrective Action Log

Action ID	Action Description	Assigned To	Completion Date	Remarks
ACT-12345	Reformulated product	Rajesh Patel	15/02/2025	Successfully resolved

Annexure-4: Stability Re-test Log

Batch Number	Re-test Date	Test Conditions	Re-test Results	Operator Name
Batch-001	15/02/2025	25°C/60% RH	Pass	Rajesh Patel

12. Revision History:

Revision Date	Revision No.	Revision Details	Reason for Revision	Approved By	Page No.	Ref. Point No.	Details of Revision
01/01/2024	V 1.0	Initial Release	First Issue	Anjali Sharma	Page 1	[Ref Point]	First Release
01/01/2025	V 2.0	Updated failure investigation process	To comply with updated GMP regulations	Anjali Sharma	Page 1	[Ref Point]	Updated procedures