Alternative sterility testing supports regulatory compliance while also directly affecting product release timing, workflow efficiency, and inventory management within compounding pharmacies. At Eagle Analytical, ScanRDI® is the fastest alternative to USP <71>, implemented to support product release for 503A compounding pharmacies operating under USP <797>.
ScanRDI® enables pharmacies to:
- Support product release decisions within 1–2 days, with same-day analytical detection may be possible in certain validated product-specific workflows
- Reduce delays between compounding and dispensing
- Minimize quarantine time and inventory holding
- Improve alignment between testing timelines and assigned beyond-use dates (BUDs)
What Is ScanRDI®?
ScanRDI® is a non-growth-based sterility testing method that uses solid-phase cytometry to detect viable microorganisms in a sample.
The method includes:
- Membrane filtration
- Fluorescent staining of viable cells
- Laser-based scanning and detection
Unlike traditional sterility testing methods described in USP <71>, ScanRDI® does not rely on microbial growth. This eliminates the need for extended incubation periods and allows analytical detection within hours following sample preparation, with final reported results typically available in 1–2 days
Because of this, ScanRDI® is used to support product release decisions, supporting timely evaluation of sterility prior to dispensing compounded sterile preparations.
Quantified Speed Advantage: Traditional vs. ScanRDI®
Method | Typical Time to Result | Release Impact |
USP <71> | 14 days | Long quarantine, delayed release |
Celsis® | 5-6 days | Moderate acceleration |
BacT/ALERT® | 5-6 days | Moderate acceleration |
ScanRDI® | 1-2 days (same-day possible) | Supports timely product release decisions |
What Needs to Be Tested?
Sterility testing is required for specific compounded sterile preparations (CSPs), including:
- Category 2 CSPs when sterility testing is required based on assigned beyond-use dates and compounding conditions
- Category 3 CSPs, where sterility testing is generally required to support assigned beyond-use dates
These requirements align with USP <797> guidelines and are essential for ensuring patient safety and regulatory compliance.
Regulatory Considerations for Rapid Sterility Testingre
Rapid sterility testing methods such as ScanRDI® may be used when properly validated for the specific product and intended use.
Key requirements include:
- Product-specific method suitability testing
- Demonstration that the alternative method is suitable and comparable to USP <71> for the intended product
- Complete and traceable documentation
ScanRDI® validation is performed in accordance with USP <1223> Validation of Alternative Microbiological Methods.
Eagle Analytical supports compounding pharmacies through method suitability, validation, and implementation, ensuring alignment with USP <797> and State Board of Pharmacy expectations.
Important Considerations for ScanRDI® Sterility Testing
ScanRDI® provides rapid detection of viable microorganisms, but appropriate application is essential.
Key considerations include:
- Detection does not rely on microbial growth
- Positive results may not consistently generate recoverable isolates for species-level identification
- Product compatibility must be confirmed through method suitability testing
For this reason, ScanRDI® is used specifically for product release testing and is typically supported by broader quality systems such as environmental monitoring.
Frequently asked questions: ScanRDI® and Rapid Sterility Testing
Why Choose Eagle Analytical for ScanRDI® Testing?
Eagle Analytical’s position is supported by over 20 years of experience working with the ScanRDI® system, with a focus on applying rapid sterility testing methods within 503A compounding environments under USP <797>.
Eagle Analytical supports compounding pharmacies through:
Over 20 years of experience supporting sterility testing for compounded sterile preparations, including Category 2 and Category 3 CSPs.
Consistent Turnaround for Release Testing:
- Results in 1–2 days
- Turnaround aligned with pharmacy dispensing workflows
- Reproducible timelines across batches
Scientifically Grounded Method Suitability:
- Product-specific method suitability testing
- Evaluation of formulation compatibility, including filtration and fluorescence considerations
- Determination of appropriate use for ScanRDI®
Regulatory-Ready Documentation:
- Clear and structured Certificates of Analysis (COAs)
- Documentation designed for traceability and audit readiness
- Alignment with USP <797> requirements
Which Sterility Testing Method Is Best?
The best sterility testing method depends on your goals:
- Choose USP <71> for traditional, growth-based confirmation
- Choose rapid growth-based methods for moderate acceleration
- Choose ScanRDI® when rapid confirmation of sterility is required to support product release timelines
For organizations looking to reduce release time from weeks to days, ScanRDI® offers a clear advantage.
How does rapid sterility testing improve beyond-use dates (BUDs)?
Rapid sterility testing methods such as ScanRDI® are used to support product release decisions, not to establish or extend beyond-use dates (BUDs).
Under current regulatory expectations, BUD assignment for compounded sterile preparations must follow USP <797> requirements, which may include sterility testing such as USP <71>, along with stability data and risk-based considerations.
