The risks behind the widespread use of siliconized syringes in the healthcare practice

A critical opinion-based review of hospital pharmacy compounding with respect to the risk of leachable substances due to the off-label use of plastic primary packaging

Hospital pharmacies play a unique role in healthcare by regularly compounding drug products (DPs) in response to hospital demands and practices, for example, drug shortages, to cater to frail and vulnerable patients with infectious, chronic or nutrition-related conditions. Drugs are compounded in precise concentrations for extended durations, sometimes involving complex formulations. A significant challenge in this context is the off-label use of short-term plastic primary packaging for long-term storage of compounded DPs, which could be due to a lack of awareness, financial constraints and inadequate regulation. Without proper risk assessments, such packaging can release potentially harmful leachable compounds, posing a serious threat to patient safety. Evaluating hospital pharmacy compounding procedures to mitigate this risk is essential. While off-label drug use is a well-known concept in hospitals, off-label use of plastic primary packaging is an entirely different practice. In both the United States and Europe, healthcare professionals, including pharmacists, are allowed to use medical devices, including primary packaging, in ways that are not explicitly approved by regulators based on their clinical judgement and best practices, taking into account the patient's best interest. However, this off-label use could bring about unique risks and challenges, especially in the highly controlled environment of hospital pharmacy compounding, where patient safety is crucial. Therefore, the current review explores the historical context and the current landscape of hospital pharmacies, investigates the potential root causes of container closure integrity issues in pharmaceutical compounding, discusses the materials of construction as well as their physical-chemical properties influencing their roles in most popular primary packaging and finally presents expert opinions aimed at identifying long-term solutions to the existing challenges regarding their off-label uses in hospital pharmacy compounding.

Impact of pneumatic tube transportation on the aggregation of monoclonal antibodies in clinical practice

Postproduction handling and in-hospital transportation of antibody drugs cause mechanical stress, including interfacial and shear stress, that can induce antibody unfolding and aggregation. The handling practices differ significantly between hospitals and the impact on protein stability is unknown. For example, the mechanical stress caused by transport via pneumatic tube systems (PTS) on therapeutic antibody aggregation is a potential safety and quality gap. The aim of this study was to investigate whether mechanical stress and PTS transportation in a hospital cause aggregation of five commonly used antibody drugs diluted in infusion bags. Orthogonal analytical methods showed that the handling and PTS transportation in this hospital did not cause aggregation of the investigated mAbs. The absence of aggregation could be explained by the reduction of interfacial stress due to headspace removal from the infusion bags and a mechanical sensor indicated that there was also only a moderate amount of mechanical stress caused by transportation with this particular PTS. Although this case study focuses on five antibody drugs and the practices in one hospital, the work demonstrates how to evaluate whether other handling and transportation practices cause significant mechanical stress that could compromise the quality and safety of antibody drugs.

Immunogenicity of monoclonal antibody: Causes, consequences, and control strategies

Antibody-based treatment was first used in 1891 for the treatment of diphtheria. Since then, monoclonal antibodies (mAbs) have been developed to treat many diseases such as cancer and act as vaccines. However, murine-derived therapeutic mAbs were found to be highly immunogenic, and caused anti-drug antibodies (ADAs) reaction, reducing their efficacy and causing severe infusion reactions. Fully human, humanised, and chimeric antibodies were then introduced for better therapeutic efficacy. With the introduction of immune response associated with mAbs immunogenicity. This review explores the immunogenicity of mAbs, its mechanism, contributing factors, and its impact on therapeutic efficacy. It also discusses immunogenicity assessment for preclinical studies and strategies for minimising immunogenicity for effective therapeutic treatment in various diseases. Finally, predicting immunogenicity in drug development is essential for selecting top drug candidates. A lot of methods can be implemented by the researchers and developers to reduce the development of ADAs while simultaneously minimising the immunogenicity reaction of mAbs.

[Translated article] Syringes for intraocular administration: A systematic review

OBJECTIVE

The off-label use in clinical practice of non-approved syringes for intravitreal drug administration has resulted in the detection of silicone oil drops in the vitreous of some patients. This situation derives from the lack of approved syringes for intraocular use in the Spanish market. The aim of this work is to review the use of syringes for intraocular administration, as well as to search for alternatives that meet the legal requirements for these unmet needs.

METHOD

A systematic review was performed following the PRISMA 2020 guidelines by searching PubMed with the descriptors: (silicone) AND (syringes) AND ((intraocular) OR (intravitreal)) and filtering all existing publications from January 2006 to December 2023, including all those articles dealing with silicone oil release in intravitreal injections and analysing the possible consequences.

RESULTS

Sixty-eight results were found, 23 of which were excluded because they did not deal with the subject under study, leaving a total of 45 articles for the systematic review. These were classified according to the conclusions obtained in 4 groups: the adverse reactions produced by silicone; the administration technique; the physicochemical aspects of silicone release; and the characteristics of the medical device. After reviewing the current manufacturers and technical data sheets of commercialised syringes, the existing syringes for this use have been collected, finding 2 that will probably be commercialised in Spain at the beginning of 2024: Zero Residual™ 0.2 ml SiO-free and VitreJect® Ophthalmic.

CONCLUSIONS

From the results obtained, it can be interpreted that the use of syringes and needles with silicone for intravitreal use is a concern for health professionals due to the implications and consequences that may arise in patients, the most important being adverse reactions, so it is necessary to have silicone-free syringes on the market that are specific for intraocular use. Safety and legality in the use of intraocular syringes and needles is essential to guarantee ocular integrity and patient health.

Syringes for intraocular administration: Systematic review

OBJECTIVE

The off-label use in clinical practice of non-approved syringes for intravitreal drug administration has resulted in the detection of silicone oil drops in the vitreous of some patients. This situation derives from the lack of approved syringes for intraocular use in the Spanish market. The aim of this work is to review the use of syringes for intraocular administration, as well as to search for alternatives that meet the legal requirements for these unmet needs.

METHOD

A systematic review was performed following the PRISMA 2020 Guidelines by searching PubMed with the descriptors: "silicone" AND "syringes" AND ("intraocular" OR "intravitreal") and filtering all existing publications from January 2006 to December 2023, including all those articles dealing with silicone oil release in intravitreal injections and analysing the possible consequences.

RESULTS

Sixty-eight results were found, 23 of which were excluded because they did not deal with the subject under study, leaving a total of 45 articles for the systematic review. These were classified according to the conclusions obtained in 4 groups: the adverse reactions produced by silicone, the administration technique, the physicochemical aspects of silicone release, and the characteristics of the medical device. After reviewing the current manufacturers and technical data sheets of commercialized syringes, the existing syringes for this use have been collected, finding two that will probably be commercialized in Spain at the beginning of 2024: Zero Residual™ 0.2 ml SiO-free and VitreJect® Ophthalmic.

CONCLUSIONS

From the results obtained, it can be interpreted that the use of syringes and needles with silicone for intravitreal use is a concern for health professionals due to the implications and consequences that may arise in patients, the most important being adverse reactions, so it is necessary to have silicone-free syringes on the market that are specific for intraocular use. Safety and legality in the use of intraocular syringes and needles is essential to guarantee ocular integrity and patient health.

Stability of ranibizumab during continuous delivery from the Port Delivery Platform

The Port Delivery System with ranibizumab (PDS) is an innovative intraocular drug delivery system that has the potential to reduce treatment burden in patients with retinovascular diseases. The Port Delivery Platform (PD-P) implant is a permanent, indwelling device that can be refilled in situ through a self-sealing septum and is designed to continuously deliver ranibizumab by passive diffusion through a porous titanium release control element. We present results for the studies carried out to characterize the stability of ranibizumab for use with the PD-P. Simulated administration, in vitro release studies, and modeling studies were performed to evaluate the compatibility of ranibizumab with the PD-P administration components, and degradation and photostability in the implant. Simulated administration studies demonstrated that ranibizumab was highly compatible with the PD-P administration components (initial fill and refill needles) and commercially available administration components (syringe, transfer needle, syringe closure). Subsequent simulated in vitro release studies examining continuous delivery for up to 12 months in phosphate buffered saline, a surrogate for human vitreous, showed that the primary degradation products of ranibizumab were acidic variants. The presence of these variants increased over time and potency remained high. The stability attributes of ranibizumab were consistent across multiple implant refill-exchanges. Despite some degradation within the implant, the absolute mass of variants released daily from the implant was low due to the continuous release mechanism of the implant. Simulated light exposure within the implant resulted in small increases in the relative amount of ranibizumab degradants compared with those seen over 6 months.

Anti-complement drugs for the treatment of geographic atrophy and the release of silicone oil

Intravitreal injections are a common procedure in ophthalmology, often using syringes coated with silicone to aid piston movement and needles coated with silicone oil to facilitate penetration of the sclera. Pegcetacoplan and avacincaptad pegol, recently approved for clinical use by the US Food and Drug Administration, have higher viscosity and seem more susceptible to entrap air bubbles compared to anti-VEGF drugs.It is plausible that both anti-complement drugs could be associated with a higher likelihood of introducing silicone oil in the vitreous because of higher viscosity, with potentially higher friction at the inner surface of syringe barrel, in the vicinity of silicone oil. In addition to this, undesirable agitation might be inadvertently promoted by some retina specialists to remove air bubbles from the drug solution.In conclusion, recent reports of silicone oil droplets in the vitreous of patients receiving pegcetacoplan injection might be related to both its viscosity and to agitation of the syringe to remove air bubbles. Since avacincaptad pegol also is viscous, though with different pH, syringe and filter needle, we might expect similar reports for this agent soon. We also recommend further studies be carried not only to clarify the current matter but also the potential association between the combination of agitation, silicone oil and inflammation or any immune response.

Etiology of Delayed Inflammatory Reaction Induced by Hyaluronic Acid Filler

The etiology and pathophysiology of delayed inflammatory reactions caused by hyaluronic acid fillers have not yet been elucidated. Previous studies have suggested that the etiology can be attributed to the hyaluronic acid filler itself, patient's immunological status, infection, and injection technique. Hyaluronic acid fillers are composed of high-molecular weight hyaluronic acids that are chemically cross-linked using substances such as 1,4-butanediol diglycidyl ether (BDDE). The mechanism by which BDDE cross-links the two hyaluronic acid disaccharides is still unclear and it may exist as a fully reacted cross-linker, pendant cross-linker, deactivated cross-linker, and residual cross-linker. The hyaluronic acid filler also contains impurities such as silicone oil and aluminum during the manufacturing process. Impurities can induce a foreign body reaction when the hyaluronic acid filler is injected into the body. Aseptic hyaluronic acid filler injections should be performed while considering the possibility of biofilm formation or delayed inflammatory reaction. Delayed inflammatory reactions tend to occur when patients experience flu-like illnesses; thus, the patient's immunological status plays an important role in delayed inflammatory reactions. Large-bolus hyaluronic acid filler injections can induce foreign body reactions and carry a relatively high risk of granuloma formation.

Presumed Silicone Oil Droplets After Intravitreal Pegcetacoplan Injections

Importance

Recently, intravitreal pegcetacoplan became the first drug to gain US Food and Drug Administration approval for the treatment of geographic atrophy associated with nonexudative age-related macular degeneration, but the administration of this medication may be associated with unanticipated posttreatment complications.

Objective

To assess the prevalence of presumed silicone oil droplets in the vitreous cavity after intravitreal injection of pegcetacoplan.

Design, Setting, and Participants

This case series study involved a retrospective record review of all 55 patients treated with intravitreal pegcetacoplan, 0.1 mL in 150-mg/mL solution, between March 24 and June 5, 2023, at a single specialty retina practice. All injections were done using needles from the kit supplied by Apellis Pharmaceuticals on a 1-mL McKesson Luer lock syringe.

Main Outcomes and Measures

The presence or absence of presumed silicone bubbles detected during dilated biomicroscopic fundus examination and/or on color fundus photographs, the presence or absence of symptoms, change in visual acuity, and/or increase in intraocular pressure.

Results

A total of 62 intravitreal pegcetacoplan injections were given to 55 patients (mean [SD] age, 83.8 [7.8] years; 33 women [60%]) from March 24 to June 5, 2023. Of the 55 patients, 16 (29%; mean [SD] age, 83.8 [7.4] years; 9 women [56%]) had presumed intravitreal silicone droplets discovered 2 to 4 weeks after treatment, 3 of which were documented on color fundus photographs. Of the 16 patients, 14 (88%) were symptomatic for new floaters that they described as persistent, while 2 (13%) were asymptomatic. There were no signs of inflammation or infection, no increases in intraocular pressure, and no changes in visual acuity for all 16 patients.

Conclusions and Relevance

A substantial percentage of patients had symptomatic floaters from presumed intravitreal silicone oil droplets after injections of pegcetacoplan using a McKesson 1-mL Luer lock syringe. These findings support consideration of informing patients of this potential adverse effect, avoiding use of the McKesson syringe, and considering use of silicone-free syringes for pegcetacoplan injections.

Removal of Free Liquid Layer from Liquid-Infused Catheters Reduces Silicone Loss into the Environment while Maintaining Adhesion Resistance

Silicone urinary catheters infused with silicone liquid offer an effective alternative to antibiotic coatings, reducing microbial adhesion while decreasing bladder colonization and systemic dissemination. However, loss of free silicone liquid from the surface into the host system is undesirable. To reduce the potential for liquid loss, free silicone liquid was removed from the surface of liquid-infused catheters by either removing excess liquid from fully infused samples or by partial infusion. The effect on bacterial and host protein adhesion was then assessed. Removing the free liquid from fully infused samples resulted in a ~64% decrease in liquid loss into the environment compared to controls, with no significant increase in deposition of the host protein fibrinogen or the adhesion of the common uropathogen Enterococcus faecalis. Partially infusing samples decreased liquid loss as total liquid content decreased, with samples infused to 70-80% of their maximum capacity showing a ~85% reduction in liquid loss compared to fully infused controls. Furthermore, samples above 70% infusion showed no significant increase in fibrinogen or E. faecalis adhesion. Together, the results suggest that eliminating free liquid layer, mechanically or through partial infusion, can reduce liquid loss from liquid-infused catheters while preserving functionality.

An exploratory study on the effect of mechanical stress on particle formation in monoclonal antibody infusions

Monoclonal antibody infusions (mAb-i) are administered for the treatment of various diseases. They are often transported over long distances from the compounding site to the site of administration. However, transport studies are typically carried out with the original drug product but not with compounded mAb-i. To address this gap, the impact of mechanical stress on the formation of subvisible/nanoparticles in mAb-i was investigated by dynamic light scattering and flow imaging microscopy. Different mAb-i concentrations were subjected to vibrational orbital shaking and stored at 2-8°C up to 35 days. The screening revealed that pembrolizumab and bevacizumab infusions show the highest propensity for particle formation. Especially bevacizumab at low concentrations exhibited an increase in particle formation. Because of the unknown health risks associated with the long-term application of subvisible particles (SVPs)/nanoparticles in infusion bags, stability studies carried out in the frame of licensing application procedures should also focus on SVP formation in mAb-i. In general, pharmacists should minimize the time of storage and mechanical stress during transport, especially in the case of low-concentrated mAb-i. Moreover, if siliconized syringes are used, they should be washed once with saline solution to minimize particle entry.