Broad Spectrum of Antibacterial Activity of a New Multipurpose Disinfecting Solution

Safety Assessment of Fatty Acid Amidopropyl Dimethylamines as Used in Cosmetics

The Cosmetic Ingredient Review Expert Panel (Panel) reviewed the safety of fatty acid amidopropyl dimethylamines, which function primarily as antistatic agents in cosmetic products. The relevant animal and human data reviewed for these ingredients indicate that they are potential dermal sensitizers that may be due in part by the sensitizing impurity, 3,3-dimethylaminopropylamine. The Panel concluded that fatty acid amidopropyl dimethylamines were safe as cosmetic ingredients when they are formulated to be nonsensitizing, which may be based on a quantitative risk assessment.

Performance of three multipurpose disinfecting solutions with a silicone hydrogel contact lens

Purpose. To evaluate the clinical performance of a silicone hydrogel (Si-Hy) soft contact lens (CL) in combination with three different multipurpose disinfecting solutions (MPDSs). Methods. This was a prospective, randomized, single-masked, crossover, and comparative study in which 31 habitual soft CL wearers were randomly assigned to one of the three MPDSs (Synergi, COMPLETE RevitaLens, and OPTI-FREE PureMoist) for 1 month with a 1-week wash-out period between each exposure. All subjects were successfully refitted with a Si-Hy CL (Biofinity). Subjects were then scheduled for follow-up visits after 1 month of lens wear, being evaluated at 2 and 8 hours after lens insertion. Visual Analogue Scales (VAS) were used to gauge comfort rating. Results. The tarsal conjunctiva showed a significantly different degree of lid redness between the MPDSs at the 2-hour visit (P < 0.05, Kruskal-Wallis test), being lower for COMPLETE RevitaLens compared to the other two MPDSs (Mann-Whitney U test). Furthermore, a significantly different degree of lid roughness at the 8-hour visit was seen (P < 0.05, Kruskal-Wallis test), being higher for Synergi (Mann-Whitney U test). The subjective comfort was similar with the three MPDSs. Conclusion. Tarsal conjunctival response should be also considered in the context of the clinical performance of MPDs at the ocular surface.

Meta-analysis of the ocular biocompatibility of a new multipurpose lens care system

Background

The purpose of this paper is to evaluate the biocompatibility of a novel multipurpose solution (MPS) with a dual disinfectant system containing polyaminopropyl biguanide and polyquaternium-1 (Biotrue®) by analysis of biomicroscopy signs and adverse events in six large clinical trials.

Methods

Data from six consecutive, prospective clinical trials conducted from February 2008 to March 2010 were combined for meta-analysis. Subjects used the new MPS daily for periods of 2 weeks to 6 months. Slit-lamp signs were graded at each follow-up visit using an ordinal scale (0, one; 1, trace; 2, mild; 3, moderate; 4, severe). Analysis for biocompatibility included tracking of greater than grade 2 slit-lamp findings and number of adverse events.

Results

A total of 1,567 subjects (3,134 eyes) and 81 clinical investigators participated in the six studies, with 1,499 subjects completing the studies. Based on subject days in the studies, there were 72,904 exposures to the MPS and 7,212 biomicroscopy examinations. The completion rate for the studies was 96.3%. Per observation incidence of any finding greater than grade 2 at the follow-up visits were: corneal staining 0.08%, limbal injection 0.04%, bulbar injection 0.04%, tarsal conjunctiva abnormality 0.09%, and neovascularization 0.01%. There were no other slit-lamp signs greater than grade 2 and no statistically significant difference between hydrogels and silicone hydrogels for any finding. There were no reports of adverse events during the trials.

Conclusion

Analysis of over 72,000 daily exposures and 7,212 eye examinations showed that the novel MPS exhibited excellent biocompatibility in subjects using daily wear hydrogel or silicone hydrogel lenses.

Ophthalmic preservatives: focus on polyquaternium-1

INTRODUCTION

Ophthalmic preservatives, such as polyquaternium-1 (PQ-1), are critical for the inhibition of growth of microbial contaminants in multi-dose bottles of topical medications. These antimicrobial agents must have a high efficacy against pathogenic organisms, while maintaining a favorable tolerability and safety profile.

AREAS COVERED

This review focuses on the ophthalmic preservative PQ-1. For comparison purposes, the most commonly used preservative, benzalkonium chloride (BAK), is also discussed. This survey focuses primarily on data collected during the past 10 years.

EXPERT OPINION

Effective drug delivery requires more than just an active ingredient that achieves its desired biological effect on end-target tissues. In addition, drugs must be stable in the containers that they are stored in, and must possess minimal undesired local and systemic side effects that can cause patients to decrease their adherence. In addressing these concerns, specifically in topical ophthalmic drops, one must take into account the active ingredients, vehicle components and preservatives. Medications with fewer adverse effects may lead to enhanced adherence to therapy; therefore, the induction of such adverse outcomes must be considered by physicians when treating patients with chronic ocular disease. Although BAK will continue to be used in ophthalmic medications, due to its familiarity and compatibility with a broad range of topical ocular formulations, PQ-1 is certainly a viable alternative in the preservative formulary armamentarium.

Lens material and formulation of multipurpose solutions affects contact lens disinfection

PURPOSE

To assess the disinfection efficacy of multipurpose solutions (MPS) against different bacterial species adhered either to silicon hydrogel or to conventional hydrogel contact lenses (CLs). The influences of the MPS formulation and the chemical composition of the lens material were investigated.

METHODS

This investigation followed the standard 14729, which establishes the guidelines for assessing CL disinfecting solutions. Two commercially available (Opti-Free(®) Express(®) and Renu(®) Multiplus) solutions and one recalled solution (Complete(®) MoisturePlus™) were used in this study. After disinfection, the number of survivors was estimated by the colony forming units' method.

RESULTS

The lens material appears to influence disinfection. The conventional hydrogel polymacon exhibited the highest disinfection scores, a fact that should be related with the lack of electrostatic attraction towards the biocides and its hydrophilicity. The MPS formulation appears to have influence in disinfection efficacy as well. For most adhered bacteria, Opti-Free(®) was capable of reducing cell concentration in 4-log.

CONCLUSION

Disinfection results from multivariate factors and this study confirmed that the lens material and the MPS play a very important role in the disinfection efficacy of CL.

Effects of contact lens multipurpose solutions on human corneal epithelial survival and barrier function

PURPOSE

To examine the effect of 4 commercially available contact lens multipurpose solutions (MPS) on the viability and barrier function of human corneal epithelial cells in vitro.

METHODS

Immortalized human corneal epithelial cells were exposed to 4 solutions, MPS A, B, C, and D with culture medium and Hanks' Balanced Salt Solution as controls. MTT assay was used to evaluate cell viability. ApopTag Fluorescein Apoptosis assay was used to detect cell death in situ. Corneal epithelial barrier function was evaluated by fluorescein permeability and immunofluorescent staining for tight junction proteins zonula occludens (ZO)-1 and occludin.

RESULTS

Corneal epithelial survival rates, evaluated by MTT assay showed no statistical difference between MPS A and the culture medium or Hanks' Balanced Salt Solution controls. MPS B, C, and D were associated with significantly less cell survival than the controls after exposure for 6 hrs (all P<0.01). Compared with the controls, the MPS A did not increase cell apoptosis, whereas the other 3 caused higher apoptotic rates. The epithelial permeability after exposure to MPS A was similar to controls and significantly lower than MPS B and MPS D (P<0.01). The tight junction proteins ZO-1 and occludin were well maintained after exposure to MPS A. In contrast, the expression of ZO-1 and occludin were largely disturbed by the other 3 MPS solutions.

CONCLUSIONS

The current marketed contact lens MPS may have negative effects on human corneal epithelial viability and barrier function. Among 4 MPS studied, MPS A maintains the cell viability and barrier function significantly better than other 3 marketed products.