Application of Visible-Residue Limit for Cleaning Validation - Pharmaceutical Technology

Latest Issue
PharmTech

Latest Issue
PharmTech Europe

Application of Visible-Residue Limit for Cleaning Validation


Pharmaceutical Technology



Figure 3: Distance and observer´s angle were studied to gauge their effects on visible-residue detection. According to data collected from trials with four observers, accuracy decreased with greater viewing distances and angles.
The viewing angle of the observer to the residue was a critical factor for detecting formulation residue. Under ambient light and at the minimum angle (~15°) (see Table II), the observers did not detect most VRLs at 15 ft and only detected a few at 20 ft. When the viewing angle increased to 30° (see Table IV), the observers detected more residue spots at 15 and 20 ft, but not enough to make a significant difference compared with data at 15°. As the viewing angle increased to 45° and 90°, the observers detected almost all VRLs at 15 ft (see Table IV) and most VRLs at 20 ft. The observers detected essentially all ARLs at 20 ft and at >30° viewing angles. When the observer's position changed with respect to the stainless steel background, observers detected all VRLs from 10 ft, at a 45° coupon angle, and with light intensities as low as 100 lx (see Appendix, Figure 7).

Observer variability was a factor in determining the VRL (6) for API and formulation residues. For this study, each factor examined had an effect on the observer's ability to detect the formulation residues. Observer detection was dependent on the formulation residue level, observer viewing distance, light intensity, and viewing angle. Certain observers had trouble detecting several formulation residues.

Observer variability increased with greater viewing distances, particularly for those beyond 10 ft (see Table II). This trend also was true of the observer angle factor. At 15° and 30° viewing angles, observer variability was comparable with other factors (see Table IV). At a viewing angle greater than 30°, the ability to detect residue increased significantly and observer variability decreased accordingly (see Figures 3 and 4). Residue detection was comparable using the portable light source and 400-lx ambient light (see Appendix, Figure 8) and was not a significant factor at decreasing light intensity levels until 100 lx, at which VRL detection was problematic (see Figure 5).

Conclusions


Figure 4: The effect of distance and observers angle on acceptable-residue detection were studied. According to data collected from trials with four observers, observer variability increased with greater viewing distances and angles.
Using a visible-residue limit (VRL) to verify equipment cleanliness is a viable possibility in a manufacturing facility for formulations with a VRL that is lower than the acceptable-residue limit (ARL). The ability to detect pharmaceutical compounds down to their VRLs has been demonstrated using formulation residue level, observer viewing distance, light intensity, and viewing angle as variables.


Figure 5: Light intensity was studied to gauge its effect on residue detection. Based on data collected from trials with four observers, using a portable light source for detection was not a significant factor at decreasing light intensity levels until 100 lx, at which detection was problematic.
The factors that affect visible-residue detection can be determined and viewing of residues can be controlled. Under defined viewing conditions, a trained observer can detect formulation residue. The observer should be within 10 ft of the equipment surface to minimize the effect of the light intensity or the viewing angle. In addition, the observer should view the surface from a >30° angle to minimize the risk of the residue blending in with the background. Finally, the ambient light level should be at least 200 lx. Otherwise a portable light source can be used.

Acknowledgments

The authors thanks Michael McQuade, Tara Lukievics, and Joseph Schariter for their efforts as observers during these studies.

Richard Forsyth* is an associate director in Worldwide GMP Quality with Merck & Co., Inc., WP53C-307, West Point, PA 19486, tel. 215.652. 7462, fax 215.652.7106
Vincent Van Nostrand is a research chemist in Pharmaceutical R&D with Merck & Co., Inc.

*To whom all correspondence should be addressed.

Submitted: June 14, 2005. Accepted: June 29, 2005.

References

1. Code of Federal Regulations, Title 21, Food and Drugs (General Services Administration, Washington, DC, Apr. 1, 1973, Part 211.67.b.6.

2. R.J. Forsyth and D. Haynes, "Cleaning Validation in a Pharmaceutical Research Facility," Pharm. Technol. 22 (9), 104–112 (1998).

3. US Food and Drug Administration, Guide to Inspection of Validation of Cleaning Processes (FDA, Rockville, MD, 1993).

4. D.A. LeBlanc, " 'Visually Clean' as a Sole Acceptance Criteria for Cleaning Validation Protocols," J. Pharm. Sci. Technol. 56 (1), 31–36 (2002).

5. D.W. Mendenhall, "Cleaning Validation," Drug Dev. Ind. Pharm . 15 (13), 2105–2114 (1989).


ADVERTISEMENT

blog comments powered by Disqus
LCGC E-mail Newsletters

Subscribe: Click to learn more about the newsletter
| Weekly
| Monthly
|Monthly
| Weekly

Survey
FDASIA was signed into law two years ago. Where has the most progress been made in implementation?
Reducing drug shortages
Breakthrough designations
Protecting the supply chain
Expedited reviews of drug submissions
More stakeholder involvement
Reducing drug shortages
27%
Breakthrough designations
9%
Protecting the supply chain
41%
Expedited reviews of drug submissions
9%
More stakeholder involvement
14%
View Results
Jim Miller Outsourcing Outlook Jim Miller Health Systems Raise the Bar on Reimbursing New Drugs
Cynthia Challener, PhD Ingredients Insider Cynthia ChallenerThe Mainstreaming of Continuous Flow API Synthesis
Jill Wechsler Regulatory Watch Jill Wechsler Industry Seeks Clearer Standards for Track and Trace
Siegfried Schmitt Ask the Expert Siegfried SchmittData Integrity
Sandoz Wins Biosimilar Filing Race
NIH Translational Research Partnership Yields Promising Therapy
Clusters set to benefit from improved funding climate but IP rights are even more critical
Supplier Audit Program Marks Progress
FDA, Drug Companies Struggle with Compassionate Use Requests
Source: Pharmaceutical Technology,
Click here