# P-1052. Impact of Chlorhexidine Elution Profiles on Antifungal Durability of Two Chlorhexidine-Coated Antimicrobial Central Venous Catheters (CVCs)

## TL;DR

This study compares two types of antimicrobial central venous catheters to see which one better prevents fungal infections over time.

## Contribution

The study introduces a new antimicrobial catheter with a slower elution profile of chlorhexidine, showing improved antifungal durability.

## Key findings

- The MRC CVC showed greater antimicrobial durability against Candida strains compared to the CSiSz CVC.
- The MRC CVC eluted chlorhexidine more slowly, retaining more of it over time compared to the CSiSz CVC.
- Statistically significant differences in microbial colonization were observed between the two catheter types at week 2.

## Abstract

The prevalence of Central Line Associated Bloodstream Infections (CLABSIs) due to Candida species continues to increase, hence CVCs with improved antifungal activities are needed. The FDA recently cleared a new antimicrobial CVC containing Chlorhexidine (C), Minocycline (M) and Rifampin (R). This makes available a second triple combination antimicrobial CVC containing antibiotics and C in addition to the widely used CVC containing C, silver (Si), and the antibiotic Sulfadiazine (Sz). Here, we measured the elution profiles over time of C from both CVCs and assessed how this impacted the antifungal efficacy and durability of the two CVCs.Average Amount of Chlorhexidine Remaining in the CVCs during ElutionLog Reductions vs Control for Viable Colonizing C. albicans and C. glabrata Recovered from Catheters during Elution

Average Amount of Chlorhexidine Remaining in the CVCs during Elution

Log Reductions vs Control for Viable Colonizing C. albicans and C. glabrata Recovered from Catheters during Elution

MRC CVCs were prepared by a sequential coating process. Commercially available CSiSz CVCs were purchased. CVCs were immersed in plasma for 24 hrs then immersed in serum for 3 weeks. At baseline (24 hrs) and weekly thereafter, segments were removed for chemical analysis of C content remaining by HPLC and for fungal colonization challenge. Challenge exposed the segments to inocula of clinical Candida CLABSI isolates for 48hrs following which the number of colonizing microbes were enumerated by sonication, serial dilution, plating and colony counting. Non-coated CVCs were controls for all testing.Median Number of CFU/segment Recovered following Microbial Challenges of C. albicans and C. glabrata

Median Number of CFU/segment Recovered following Microbial Challenges of C. albicans and C. glabrata

Statistical comparisons of CSiSz and MRC CVCs are indicated by horizontal brackets and p-values are indicated above the brackets showing whether differences were statistically significant (if p< 0.05).

Table 1 presents the average amount of C remaining in the CVCs as they eluted. Table 2 presents log reductions versus control for viable colonizing C. albicans (CA) and C. glabrata (CG) recovered from the catheters as they eluted. Figure 1 presents the median number of CFU/segment recovered following microbial challenges of CA and CG. The differences in antimicrobial activity between the MRC CVC and CSiSz CVC were statistically significant (p=0.005 for CA and p=0.004 for CG) at week 2 (Figure 1). The CSiSz CVC eluted approximately 80% of its starting C in the first 24 hrs and over 85% after 1 week. Very little C eluted after 1 week. The MRC CVC eluted approximately 30% of its initial C at 1 week, 50% at 2 weeks and 55% at 3 weeks.

Corresponding to the elution differences, the MRC CVC had greater antimicrobial durability against both Candida strains, most pronounced at week 2.

Joel Rosenblatt, PhD, Citius Pharmaceuticals, Inc.: Advisor/Consultant|Citius Pharmaceuticals, Inc.: Grant/Research Support|Citius Pharmaceuticals, Inc.: Patent|Citius Pharmaceuticals, Inc.: Ownership Interest|Citius Pharmaceuticals, Inc.: Stocks/Bonds (Public Company)|Spectrum Vascular: SV Spectrum MRC Central Venous Catheter; SV Spectrum MR Central Venous Catheter; SV Central Venous Catheter|Spectrum Vascular: Ownership Interest Anne-Marie Chaftari, MD, Citius Pharmaceuticals, Inc., Cranford, New Jersey, USA: Grant/Research Support Dennis Kraus, MD, Spectrum Vascular: Patent|Spectrum Vascular: Ownership Interest Issam I. Raad, Distinguished Professor, Citius Pharmaceuticals, Inc. (Grant/Research Support): Advisor/Consultant|Citius Pharmaceuticals, Inc. (Grant/Research Support): Grant/Research Support|Citius Pharmaceuticals, Inc. (Grant/Research Support): Patent|Citius Pharmaceuticals, Inc. (Grant/Research Support): Ownership Interest|Citius Pharmaceuticals, Inc. (Grant/Research Support): Stocks/Bonds (Public Company)|Spectrum Vascular: Patent|Spectrum Vascular: Ownership Interest