Standard Operating Procedure for Priming and Repriming Testing Method in Analytical Method Development
| Department | Analytical Method Development |
|---|---|
| SOP No. | SOP/AMD/244/2025 |
| Supersedes | SOP/AMD/244/2022 |
| Page No. | Page 1 of 12 |
| Issue Date | 21/05/2025 |
| Effective Date | 23/05/2025 |
| Review Date | 21/05/2026 |
1. Purpose
To describe the procedure for evaluating the priming and repriming characteristics of nasal spray and inhalation delivery systems to ensure dose accuracy after initial activation and re-use
2. Scope
This SOP applies to Analytical Method Development (AMD) scientists evaluating the performance of nasal sprays, metered-dose inhalers (MDIs), or other pressurized or pump-based delivery devices under initial and post-interruption usage conditions.
3. Responsibilities
- Analytical Scientist: Conducts the priming and repriming tests and records results.
- QC Analyst: Assists in dose collection and ensures environmental conditions are controlled.
- QA Executive: Reviews the test data and validates the method for implementation.
4. Accountability
The Head of Analytical Method Development is accountable for ensuring method accuracy, adherence to regulatory guidance, and fitness-for-purpose in evaluating device readiness after storage.
5. Procedure
5.1 Definitions
- Priming: Initial activation of the device to fill metering chamber and enable consistent dose delivery.
- Repriming: Re-activation of the device after an extended period of non-use to restore uniform dosing.
5.2 Apparatus and Setup
- Dose collection system (e.g., DUSA)
- Analytical balance and HPLC system (if applicable)
- Controlled room temperature and humidity (23 ±2°C, 50 ±5% RH)
5.3 Priming Evaluation
- Select 3–6 units from the batch for testing.
- Shake device and actuate into a waste container until consistent spray is observed (usually 3–5 actuations).
- Start dose collection from the first actuation after priming is complete.
- Collect next 3 actuations and measure delivered dose.
- Compare these doses with the labeled claim.
5.4 Repriming Evaluation
- After priming, store devices horizontally for 14 days (or label-specific duration).
- Without shaking, actuate and record first spray — should show reduction in dose.
- Reprime as per label instructions and collect 3 doses after repriming.
- Evaluate recovery of uniformity in doses post-repriming.
5.5 Analytical Measurement
- Analyze collected samples using validated HPLC method or gravimetric analysis (for spray weight).
- Calculate:
Delivered Dose (mg) = Sample Peak Area / Standard Peak Area × Standard Concentration × Dilution Factor
5.6 Acceptance Criteria
- Dose after priming: 85–115% of label claim.
- Reprimed dose recovery within ±10% of primed dose values.
- RSD of triplicate sprays ≤ 6.0%.
5.7 Documentation
- Record device ID, actuation count, duration of storage, and assay results.
- Include observations of spray pattern or anomalies.
6. Abbreviations
- DDU: Delivered Dose Uniformity
- DUSA: Dose Uniformity Sampling Apparatus
- HPLC: High Performance Liquid Chromatography
- RSD: Relative Standard Deviation
7. Documents
- Priming and Repriming Data Log – Annexure-1
- Storage Log Sheet – Annexure-2
- Validation Summary Report – Annexure-3
8. References
- FDA Guidance: Nasal Spray and Inhalation Solution Product Quality Testing
- USP <601>: Aerosols, Nasal Sprays, and Metered-Dose Inhalers
- ICH Q2(R1): Validation of Analytical Procedures
9. SOP Version
Version: 2.0
10. Approval Section
| Prepared By | Checked By | Approved By | |
|---|---|---|---|
| Signature | |||
| Date | |||
| Name | Reema Joshi | Anil Verma | Sunita Reddy |
| Designation | Analytical Scientist | QA Reviewer | Head – AMD |
| Department | Analytical Method Development | QA | Analytical Method Development |
11. Annexures
Annexure-1: Priming and Repriming Data Log
| Device ID | Primed Dose (mg) | Reprimed Dose (mg) | % Difference | RSD (%) | Status |
|---|---|---|---|---|---|
| NS-PRM-001 | 0.102 | 0.099 | 2.9% | 3.5 | Pass |
Annexure-2: Storage Log Sheet
| Device ID | Storage Start Date | Storage End Date | Condition | Verified By |
|---|---|---|---|---|
| NS-PRM-001 | 01/05/2025 | 15/05/2025 | 23°C / 50% RH | QA Officer |
Annexure-3: Validation Summary Report
Priming and repriming evaluation method validated for nasal spray NS-25. Results met acceptance limits. Doses recovered after 14-day storage showed 98% of initial dose. Method deemed robust and reproducible.
Revision History:
| Revision Date | Revision No. | Details | Reason | Approved By |
|---|---|---|---|---|
| 21/05/2025 | 2.0 | Revised to include RSD criteria and storage log annexure | Annual Review & Compliance Update | Sunita Reddy |
| 14/03/2022 | 1.0 | Initial SOP Release | New SOP | QA Head |