Multiple use of preservative-free single dose unit dexamethasone 0.1% eye drops is safe within 24 hours.

BACKGROUND: Unpreserved single-dose unit (SDU) eye drops are commonly used to avoid benzalkonium chloride-related toxicity. Although intended for single use, many patients report off-label repeated use of SDUs over a prolonged period. We investigated whether repeated use of dexamethasone 0.1% SDUs in the same patient increases the bacterial contamination rate. METHODS: We prospectively enrolled patients scheduled for inpatient corneal and glaucoma surgery receiving dexamethasone 0.1% SDU four times per day from the same vial. To assess contamination rates, one drop from the vial was cultured immediately after opening the SDU (t0), 10 hours later after four drop applications (t10) and 24 hours after opening without further drop applications (t24). Conjunctival swabs were taken before and after drop application. Contamination rate was assessed with a standard clinical culturing protocol without introducing a positive control. RESULTS: 110 eyes of 109 patients were evaluated. Drops collected immediately after opening the SDU (t0) were contaminated in 9/110 cultures (8.1%). At t10, 13/110 cultures were contaminated (11.8%; p=0.267) and 11/110 at t24 (10.0%; t24 vs t0; p=1.00). In 5 of 21 cases of contaminated drops at t10 and/or t24, the same isolates were cultured from the initial conjunctival swab and the SDU. In three cases, the same bacterial species was found in consecutive samples. CONCLUSION: The contamination rate of the SDU did not increase after multiple use within 24 hours. Contamination from fingertip flora was more likely than from ocular surface flora. Reuse of dexamethasone 0.1% SDU in the same patient within 24 hours appears to be safe.

Preservative-Free Fixed Combination of Tafluprost 0.0015% and Timolol 0.5% for Treatment-Naive Patients with Open-Angle Glaucoma.

PURPOSE: To assess efficacy, safety, and tolerability of the preservative-free (PF) fixed-dose combination (FC) of tafluprost 0.0015%/timolol 0.5% (PF tafluprost/timolol FC) in treatments-naive patients with primary open-angle glaucoma (POAG). METHODS: This was a retrospective, real-world clinical practice setting study that included 107 eyes of 107 subjects with POAG who had never been treated for glaucoma. All subjects were received PF tafluprost/timolol FC once daily. Intraocular pressure (IOP) levels were documented for each eye at the untreated baseline and up to 6 months after the initiation of medical treatment. All adverse events, including ocular and systemic adverse reactions, were recorded. Additionally, the reasons for medication discontinuations were thoroughly documented. RESULTS: A total of 32 POAG patients with high-baseline IOP (>21 mmHg) and 75 with normal-baseline IOP were included in the study. The subjects' baseline mean age was 62.4 ± 8.7 years (range, 26.0-85.0 years); among them, 42 were female (39.3%). Mean IOP at baseline for all patients was 18.6 ± 4.3 mmHg. The mean IOP at 6 months was 12.6 ± 4.7 mmHg, representing a significant decrease compared to the baseline (-32%, p < 0.001). In POAG patients with high-baseline IOP, mean IOP was significantly lowered from 28.0 ± 5.7 mmHg at baseline to 18.0 ± 5.5 mmHg (-35%, p < 0.001); in patients with normal-baseline IOP, from 14.6 ± 3.4 mmHg at baseline to 10.3 ± 4.1 mmHg (-29%, p < 0.001). PF tafluprost/timolol FC was well-tolerated and safe. After 6 months, 97.2% of all patients remained on therapy. CONCLUSIONS: In this real-world observational study, once-daily treatment with PF tafluprost/timolol FC demonstrated clinically relevant and statistically significant efficacy, as well as safety and good tolerability, in treatment-naive patients diagnosed with POAG.

Repeated-dose toxicity and toxicokinetic study of isobutylparaben in rats subcutaneously treated for 13 weeks.

Parabens have historically served as antimicrobial preservatives in a range of consumables such as food, beverages, medications, and personal care products due to their broad-spectrum antibacterial and antifungal properties. Traditionally, these compounds were believed to exhibit low toxicity, causing minimal irritation, and possessing limited sensitization potential. However, recent evidence suggests that parabens might function as endocrine-disrupting chemicals (EDCs). Consequently, extensive research is underway to elucidate potential human health implications arising from exposure to these substances. Among these parabens, particular concerns have been raised regarding the potential adverse effects of iso-butylparaben (IBP). Studies have specifically highlighted its potential for inducing hormonal disruption, significant ocular damage, and allergic skin reactions. This study aimed to evaluate the prolonged systemic toxicity, semen quality, and estrus cycle in relation to endocrine disruption endpoints, alongside assessing the toxicokinetic behavior of IBP in Sprague-Dawley rats following a 13-week repeated subcutaneous administration. The rats were administered either the vehicle (4% Tween 80) or IBP at dosage levels of 2, 10, and 50 mg/kg/day for 13 weeks. Blood collection for toxicokinetic study was conducted on three specified days: day 1 (1st), day 30 (2nd), and day 91 (3rd). Systemic toxicity assessment and potential endocrine effects were based on various parameters including mortality rates, clinical signs, body weights, food and water consumption, ophthalmological findings, urinalysis, hematological and clinical biochemistry tests, organ weights, necropsy and histopathological findings, estrus cycle regularity, semen quality, and toxicokinetic behavior. The findings revealed that IBP induced local irritation at the injection site in males at doses ≥ 10 mg/kg/day and in females at 50 mg/kg/day; however, systemic toxicity was not observed. Consequently, the no-observed-adverse-effect level (NOAEL) for IBP was determined to be 50 mg/kg/day in rats of both sexes, indicating no impact on the endocrine system. The toxicokinetics of IBP exhibited dose-dependent systemic exposure, reaching a maximum dose of 50 mg/kg/day, and repeated administration over 13 weeks showed no signs of accumulation.

Preservative-Free Bimatoprost 0.01% Ophthalmic Gel for Glaucoma Therapy: A Phase III Randomized Controlled Trial.

PRCIS: Noninferiority of efficacy was demonstrated for a preservative-free bimatoprost 0.01% compared with BAK-containing bimatoprost 0.01% following a 12-week treatment period in patients with open angle glaucoma or ocular hypertension. Improved tolerability, in particular conjunctival hyperemia, was also observed. PURPOSE: To evaluate the intraocular pressure (IOP)-lowering efficacy and safety of a preservative-free bimatoprost 0.01% ophthalmic gel (PFB 0.01% gel) compared with preserved bimatoprost 0.01% (PB 0.01%). DESIGN: Phase III, international, multicenter, randomized, 2-parallel group, investigator-masked, 3-month treatment duration. METHODS: Patients with glaucoma or ocular hypertension were randomized after a 7-week run-in/washout period to receive once-daily PFB 0.01% gel (n=236) or PB 0.01% (n=249) for 3 months. The primary efficacy measure was changed from baseline in IOP at week 12. Safety measures included adverse events (AEs) and assessment of conjunctival hyperemia. RESULTS: The mean changes from baseline in IOP at week 12 in the PFB 0.01% gel and PB 0.01% were -9.72±2.97 and -9.47±3.06 mm Hg, respectively, at 8 am , -9.41±3.03 and -9.19±3.12 mm Hg at 10 am , and -8.99±3.36 and -8.54±3.44 mm Hg at 4 pm . Noninferiority of PFB 0.01% gel to PB 0.01% was demonstrated at week 12 based on predetermined criteria (upper 95% CI margin of 1.5 mmHg at all time points). The most frequently reported AE was conjunctival hyperemia; 13 (5.5%) patients with PFB 0.01% gel and 17 (6.8%) patients with PB 0.01%. The percentage of patients experiencing a worsening from baseline in conjunctival hyperemia score was lower with PFB 0.01% gel compared to PB 0.01% at week 6 (20.1% vs. 29.3%, respectively) and week 12 (18.3% vs. 30.4%, respectively). CONCLUSIONS: PFB 0.01% ophthalmic gel has the same efficacy in lowering IOP as PB 0.01% and demonstrated less aggravation of conjunctival hyperemia at weeks 6 and 12.

Patterns of positive patch test reactions to formaldehyde and formaldehyde releasers at the Finnish Institute of Occupational Health from 2007 to 2020.

BACKGROUND: Formaldehyde is an important contact sensitizer. Formaldehyde releasing substances induce positive reactions in formaldehyde-allergic patients, but there are also reactions independent of formaldehyde allergy. In an earlier study, stronger formaldehyde reactions led to more positive reactions to quaternium-15. OBJECTIVES: To analyze patterns of positive patch test reactions to formaldehyde and different formaldehyde releasers. METHODS: Patch test files of 1497 patients investigated during the period November 2007-August 2020 were retrospectively reviewed for positive reactions to formaldehyde and its releasers. During the study period, almost all (≥99.3%) patients were tested with a formaldehyde dilution series and six formaldehyde releasers. RESULTS: Ninety-three patients tested positive to formaldehyde; 80% of these had positive reactions to at least one formaldehyde releaser, most often benzylhemiformal. There were only nine independent contact allergies to formaldehyde releasers. There were only two reactions to 2-bromo-2-nitropropane-1,3-diol and they occurred in formaldehyde-negative patients. In patients with extreme (+++) reactions to formaldehyde, concomitant positive reactions to any of the other 11 investigated formaldehyde releasers were more common than in patients with milder formaldehyde reactions. CONCLUSIONS: Strong formaldehyde reactions were associated with positive reactions to formaldehyde releasers.

Thirteen-week subcutaneous repeated dose toxicity study of butylparaben and its toxicokinetics in rats.

Parabens are widely used preservatives in cosmetics and pharmaceutical products and are approved as food additives. These chemicals have been considered safe for many years. However, the literature classifies parabens as endocrine-disrupting chemicals, and an assessment of their influence on the endocrine system and systemic toxicity is important. This study explored long-term systemic toxicity, effects on the endocrine system, and toxicokinetic behavior after repeated subcutaneous administration of butylparaben to Sprague-Dawley rats. Rats were treated with vehicle (4% Tween 80) or butylparaben at dose levels of 2, 10, and 50 mg/kg/day for 13 weeks. Assessment of systemic toxicity and endocrine-disrupting effects was based on mortality; clinical signs; body weight; food and water consumption; ophthalmological findings; urinalysis; hematology and clinical biochemistry; organ weights; necropsy and histopathological findings; regularity and length of the estrous cycle; semen quality; and toxicokinetic behavior. Female uterine weight and estrous cycle, and male semen quality indicated no estrogenic effects. Butylparaben induced local irritation at the injection site in both sexes at a dose of 50 mg/kg/day, but systemic toxicity was not observed. Therefore, the no-observed-adverse-effect level of butylparaben is set at 50 mg/kg/day in rats of both sexes. Butylparaben was without endocrine system effects at this dose. Butylparaben displays dose-dependent systemic exposure up to the maximum dose of 50 mg/kg/day and repeated administration of butylparaben for 13 weeks shows no bioaccumulation.

Developing a cosmetic series: Results from the ESSCA network, 2009-2018.

BACKGROUND: There is considerable variability across European patch test centres as to which allergens are included in local and national cosmetics series. OBJECTIVES: To propose a standardized, evidence-based cosmetic series for Europe based on up-to-date analysis of relevant contact allergens. METHODS: We collated data from the European Surveillance System on Contact Allergies (ESSCA) from 2009 to 2018 to determine which cosmetic allergens produce a high yield of contact allergy. Contact allergens with a prevalence of >0.3% that were considered relevant were included. Rare contact allergens were excluded if deemed no longer relevant or added to a supplemental cosmetic series for further analysis. RESULTS: Sensitization prevalences of 39 cosmetic contact allergens were tabulated. Thirty of these allergens yielded >0.3% positive reactions and are therefore included in our proposed European cosmetic series. Six were considered no longer relevant and therefore excluded. Three were included in a supplementary European cosmetic series. An additional nine allergens were included in either the core or supplemental European cosmetic series following literature review. CONCLUSION: We have derived a potential European cosmetic series based upon the above methods. This will require ongoing investigation based upon the changing exposure profiles of cosmetic allergens as well as new and evolving substances.

Propylparaben Reduces the Long-Term Consequences in Hippocampus Induced by Traumatic Brain Injury in Rats: Its Implications as Therapeutic Strategy to Prevent Neurodegenerative Diseases.

BACKGROUND: Severe traumatic brain injury (TBI), an important risk factor for Alzheimer's disease, induces long-term hippocampal damage and hyperexcitability. On the other hand, studies support that propylparaben (PPB) induces hippocampal neuroprotection in neurodegenerative diseases. OBJECTIVE: Experiments were designed to evaluate the effects of subchronic treatment with PPB on TBI-induced changes in the hippocampus of rats. METHODS: Severe TBI was induced using the lateral fluid percussion model. Subsequently, rats received subchronic administration with PPB (178 mg/kg, TBI+PPB) or vehicle (TBI+PEG) daily for 5 days. The following changes were examined during the experimental procedure: sensorimotor dysfunction, changes in hippocampal excitability, as well as neuronal damage and volume. RESULTS: TBI+PEG group showed sensorimotor dysfunction (p < 0.001), hyperexcitability (64.2%, p < 0.001), and low neuronal preservation ipsi- and contralateral to the trauma. Magnetic resonance imaging (MRI) analysis revealed lower volume (17.2%; p < 0.01) and great damage to the ipsilateral hippocampus. TBI+PPB group showed sensorimotor dysfunction that was partially reversed 30 days after trauma. This group showed hippocampal excitability and neuronal preservation similar to the control group. However, MRI analysis revealed lower hippocampal volume (p < 0.05) when compared with the control group. CONCLUSION: The present study confirms that post-TBI subchronic administration with PPB reduces the long-term consequences of trauma in the hippocampus. Implications of PPB as a neuroprotective strategy to prevent the development of Alzheimer's disease as consequence of TBI are discussed.

High-Frequency Application of Cationic Agents Containing Lubricant Eye Drops Causes Cumulative Corneal Toxicity in an Ex Vivo Eye Irritation Test Model.

Purpose: High-frequency applied cetalkonium chloride (CAC) and benzalkonium chloride (BAC) 0.02% did not hamper corneal healing in a living rabbit model of induced corneal erosion. In contrast, the ex vivo eye irritation test (EVEIT) shows inhibition of healing for these substances. In a systematic ex vivo reproduction of the in vivo experiments, we discuss the background of these differences. Methods: Excised rabbit corneas (n = 5 per group) were cultured in artificial anterior chambers (EVEIT). Four erosions were induced for each cornea before starting regular 21 installations/day over 3 days of (1) CAC containing eye drops (Cationorm®), (2) 0.02% BAC. Corneal fluorescein staining, quantification of glucose-/lactate consumption, and histology were performed. Results: BAC 0.02% treated corneas showed increased epithelial lesions from 10.13 ± 0.65 mm2 to 10 ± 0.8 mm2 on day 0, to 86.82 ± 5.18 mm2 (P < 0.0001) by day 3. After a trend toward smaller lesions for CAC on day 1, erosion sizes increased significantly by day 3 from 9.82 ± 0.30 mm2 to 29.51 ± 16.87 mm2 (P < 0.05). For 1 cornea, corneal erosions nearly disappeared on day 3 (0.89 mm2). Corneal lactate increased significantly for BAC and CAC, whereas glucose concentrations were unchanged. Histology revealed disintegration of the corneal structures for both compounds. Conclusions: The data underline the EVEIT as a predictive toxicity test to show side effects in a time-compressed manner. The consistency of these predictions was previously demonstrated by the EVEIT for BAC, phosphate buffer, and others. The EVEIT is suited for a chronic application prediction of tolerability and toxic side effects of eye drops in particular, and other chemicals in general.

In vivo demonstration of immunologic cross-reactivity to octylisothiazolinone in patients primarily and strongly sensitized to methylisothiazolinone.

BACKGROUND: Notwithstanding that concomitant exposure to different isothiazolinone derivatives may result in concomitant sensitization, clinical and animal studies have suggested cross-reactivity between these derivatives, notably between methylisothiazolinone (MI) and octylisothiazolinone (OIT). OBJECTIVE: To investigate if patients sensitized to MI show cross-reactions to OIT and/or to benzisothiazolinone (BIT) by applying the concept of the re-test method. PATIENTS AND METHODS: From March to October 2019 consecutive patients were patch tested with MI 0.2% aqueous in duplicate at the two lower corners of both shoulder blades. Patients sensitized to MI, but not to OIT 0.1% petrolatum (pet.) nor to BIT 0.1% pet., were re-tested, 2 months later, with the latter two derivatives at the skin sites where the MI reactions had fully disappeared. RESULTS: Of 116 patients, 15 (13%) were sensitized to MI, eight of these not sensitized to BIT nor to OIT. Of these, seven patients, all (very) strongly sensitized to MI, were re-tested: five patients showed positive patch test reactions to OIT 0.1% pet.; one patient to OIT 0.1% pet. and BIT 0.1% pet.; and one other patient showed no reactions. CONCLUSION: This study suggests that patients primarily and strongly sensitized to MI may show immunologic cross-reactions to OIT, and to a far lesser extent to BIT.

Influence of timolol, benzalkonium-preserved timolol, and benzalkonium-preserved brimonidine on oxidative stress biomarkers in the tear film.

PURPOSE: The objective of this study was to investigate the influence of topical preservative-free timolol, benzalkonium chloride(BAC)-preserved timolol, BAC-preserved timolol, and BAC-preserved brimonidine on total protein concentration, advanced oxidation protein products (AOPP) content, total sulfhydryl groups content, the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), as well as Total Oxidant Status (TOS), Total Antioxidant Response, and Oxidative Stress Index (OSI) in the tear film. METHODS: The patients were divided into four groups: group C (n = 25)-control group-subjects who did not use topical antiglaucoma medications, group T (n = 17)-patients using topical preservative-free timolol, group T + BAC (n = 24)-patients using topical BAC-preserved timolol, and group BR + BAC (n = 19)-patients using topical BAC-preserved brimonidine. RESULTS: The SOD, CAT, and GPx activities as well as AOPP, TOS, and OSI were found to be higher in the tear film of patients treated with BAC-preserved topical timolol or brimonidine in comparison with patients treated with preservative-free timolol or patients who did not use antiglaucoma topical medications. CONCLUSIONS: This indicates that using BAC-preserved topical medications increases oxidative stress in the tear film and may, in the long-term, contribute to the clinical presentation of dry eye disease.

Continuous Albuterol With Benzalkonium in Children Hospitalized With Severe Asthma.

BACKGROUND AND OBJECTIVES: The albuterol dropper bottle used to prepare solutions for continuous nebulization contains the preservative benzalkonium chloride (BAC). BAC, by itself, has been shown to cause bronchospasm. We hypothesized that BAC would decrease the therapeutic efficacy of albuterol in patients with acute asthma exacerbations. METHODS: We performed a retrospective cohort study comparing the clinical outcomes of patients <18 years of age receiving continuous nebulized albuterol with and without BAC. For the primary end point (duration of continuous albuterol nebulization), we compared the 2 groups with Kaplan-Meier estimate of survival curves, conducted a log-rank test of difference, and adjusted for baseline characteristics using multivariable Cox regression. A P value <.05 was considered significant. RESULTS: A total of 477 patients were included in the analysis (236 exposed to BAC and 241 controls). The duration of continuous nebulization was significantly longer in the BAC group than in the control group (median of 9 vs 6 hours; 15.7% required continuous nebulization compared to 5.8% of controls at 24 hours). The control group was 79% more likely to stop continuous nebulization at any particular point in time (hazard ratio 1.79; 95% confidence interval: 1.45 to 2.22; P < .001) and 43% more likely to stop additional respiratory support (hazard ratio 1.43; 95% confidence interval: 1.16 to 1.75; P < .001). CONCLUSIONS: BAC is a functional albuterol antagonist associated with a longer duration of continuous albuterol nebulization treatment and additional respiratory support, suggesting that preservative-free albuterol formulations are safer for use in continuous nebulization.

Antimicrobial Effectiveness in Eye Drops: Limited Sterility versus Reduction in Microbial Count.

Eye drops are sterile preparations intended for instillation into the eye. All major pharmacopoeias require these products to pass the antimicrobial effectiveness test (AET). This test is similar to that used for an oral dosage form despite the fact that both product categories differ in their microbiological specifications. The eye drops might pass the official requirements of the AET, but in practice, contaminants introduced into the preparation might not be killed before its next use by the patient and this may compromise ocular health. The objective of this work was to investigate the possible application of a limited sterility testing in a multichallenge test that mimics more closely real life use of eye drops. The AET was performed on 12 brands of eye drops, and results were compared with the suggested pass criteria of various pharmacopoeias. The multichallenge test was designed and used to demonstrate the ability of each tested product to kill the entire challenge organism population within a few hours. The results demonstrated that all products investigated complied with the AET acceptance requirements of the USP <51> and the "B" criteria of the European Pharmacopoeia (Ph Eur) <5.1.3>. Only two of the tested products did not comply with the no recovery term of Ph Eur <5.1.3> "A" criteria. Products repeatedly challenged with Pseudomonas aeruginosa ATCC 9027 (103 CFU/mL) were found to be self-sterilizing within 2 h of each inoculation. In conclusion, all tested products passed the acceptance criteria of the USP <51>, class B of the Ph Eur <5.1.3>, and the multichallenge test. The size of the challenge organism population in the AET seems to be severe for eye drops, and the pass criteria of the British Pharmacopoeia Appendix XVI are the most stringent. The no recovery term given in the Ph Eur <5.1.3> should be defined to a specified range.

Preservative-free versus preserved brimonidine %0.15 preparations in the treatment of glaucoma and ocular hypertension: short term evaluation of efficacy, safety, and potential advantages.

Purpose: To compare the efficacy, safety, and potential advantages of the preservative-free versus preserved brimonidine %0.15 preparations in patients with primer open-angle glaucoma (POAG) or ocular hypertension (OHT).Methods: Forty-two eyes of the 21 treatment-naive patients with POAG or OHT were enrolled in this study. Eyes were randomly assigned to receive brimonidine-purite 0.15% or preservative-free brimonidine 0.15% two times daily. Efficacy of the two eye drops was assessed by measuring the intraocular pressure (IOP) at 9-10 am at baseline and week 4. Safety and potential advantages of the drops were evaluated at weeks 4 in terms of ocular symptoms and tear parameters. Ocular symptom values of the patients were evaluated with a scale of 0-4 (0 = no discomfort and 4 = severe discomfort).Results: Both of the brimonidine tartrate formulations resulted in statistically similar IOP reduction (preserved formulation; -5.2 mmHg [22.9% reduction] preservative-free formulation; -5.7 mmHg [24.1% reduction], p = 0.37). It was found that brimonidine tartrate formulations with and without topical preservatives did not produce a statistically significant difference in pain, stinging, and blurred vision at the upon instillation (p > 0.05). However, the burning sensation was significantly higher in the preservative-free formulation at the first instillation compared to the preserved formulation (p = 0.01). Also, there was no statistically significant difference between the two formulations in terms of symptoms (itching, burning, tearing, stinging, and photophobia) and tear parameters during the day (p > 0.05).Conclusions: Although topical preservative-free brimonidine tartrate treated eyes had a more burning sensation at the first drop, the two formulations were similar in terms of ocular tolerability in the short term period. Also, both formulations were found to reduce IOP at a similar rate.

Methylisothiazolinone and isothiazolinone allergy.

Methylisothiazolinone (MI) is a preservative commonly used in water-based personal care products. Increases in the allowable concentration of MI alone in these products has led to an epidemic of allergic contact dermatitis (ACD). Although personal care products are the most common source of MI contact allergy, other novel exposures include household products, industrial chemicals, paint, slime, and adhesive agents. Other isothiazolinones such as benzisothiazoline (BIT) and octylisothiazolinone (OIT) are uncommon in personal care products but have been found in leather products, glue, industrial chemicals, paints, and cleaning products. There may be cross-reactivity between OIT and MI, and a minority of patients who are allergic to MI are cosensitized to BIT. In this article, we review MI and related isothiazolinone chemicals.

Thimerosal induces skin pseudo-allergic reaction via Mas-related G-protein coupled receptor B2.

BACKGROUND: Thimerosal has been used as a preservative in many products which may cause contact dermatitis. It is the second most common allergen in positive patch test reactions, though being a clinical irrelevant allergen. Thimerosal-induced contact dermatitis is generally considered to be a delayed-type hypersensitivity reaction, but it is difficult to explain the fact that most patients develop an allergic reaction upon first encounter with thimerosal. Recent studies have demonstrated the association between Mas-related G protein coupled receptor X2 (MRGPRX2) and pseudo-allergic reactions which occur at the first contact with stimulation. This suggests the possibility that thimerosal may cause contact dermatitis via MRGPRX2 mediated mechanism. OBJECTIVES: To investigate the role of Mas-related G-protein coupled receptor B2 (MrgprB2)/MRGPRX2 in contact dermatitis induced by thimerosal. METHODS: Thimerosal induced pseudo-allergic reactions via MrgprB2/ MRGPRX2 were investigated using a novel skin pseudo-allergic reaction mouse model, footpad swelling and extravasation assays in vivo and mast cell degranulation assay in vitro. RESULTS: Thimerosal induced contact dermatitis in dorsal skin and footpad swelling in wild-type mice, but had no significant effect in MrgprB2-knockout mice. Thimerosal-induced dermatitis is characterized by infiltration of inflammatory cells and elevation of serum histamine and inflammatory cytokines, rather than elevation of serum IgE level. Thimerosal increased the intracellular Ca2+ concentration in HEK293 cells overexpressing MrgprB2/MRGPRX2. Downregulation of MRGPRX2 resulted in the reduced degranulation of LAD2 human mast cells. CONCLUSIONS: MrgprB2 mediates thimerosal-induced mast cell degranulation and pseudo-allergic reaction in mice. MRGPRX2 may be a key contributor to human contact dermatitis.

Noninferiority of Preservative-free Versus BAK-preserved Latanoprost-timolol Fixed Combination Eye Drops in Patients With Open-angle Glaucoma or Ocular Hypertension.

PRéCIS:: Noninferiority of efficacy was demonstrated for a preservative-free latanoprost-timolol fixed combination compared with a BAK-containing formulation at 84 days after treatment in patients with open-angle glaucoma or ocular hypertension. PURPOSE: The purpose of this study was to compare the effect on intraocular pressure and safety of preservative-free latanoprost-timolol fixed combination (T2347) to benzalkonium chloride-preserved latanoprost-timolol fixed combination in patients with open-angle glaucoma or ocular hypertension. METHODS: Phase III, randomized, parallel-group, investigator-masked study in 10 countries. A total of 242 patients aged 18 years or older with open-angle glaucoma or ocular hypertension in both eyes controlled with a preserved latanoprost-timolol fixed combination (15.7±2.4 mm Hg overall before inclusion) were randomized at day 0 with no washout period to receive the preservative-free alternative T2347 (N=127) or remain on the preserved comparator (N=115) for 84 days. Intraocular pressure changes from day 0 were measured at 9:00 am (±1 hour) on day 42 and day 84, and noninferiority of T2347 to the preserved comparator was analyzed statistically at day 84. Safety parameters were also reported. RESULTS: The mean change in intraocular pressure from baseline to day 84 was -0.49±1.80 mm Hg for preservative-free T2347 and -0.49±2.25 mm Hg for the preserved comparator. These results met the noninferiority limits. Similar results were observed at day 42. There was no difference between groups in the incidence of adverse events or ocular signs. The total ocular symptoms score was better for T2347 than BPLT upon instillation at day 84 (45.9%/44.3%/9.8% of patients with improvement/no change/worsening vs. 33.6%/47.3%/19.1%; P=0.021), reflecting improvements in individual symptoms such as irritation/burning/stinging (P<0.001), and itching (P<0.01) on day 84. CONCLUSIONS: Preservative-free latanoprost-timolol fixed combination T2347 showed noninferior efficacy compared with the preserved comparator and was well tolerated.

Patient-Reported Nonadherence with Glaucoma Therapy.

Purpose: Effective glaucoma therapy relies to a great extent on the patients' ability to regularly self-administer eye drops. This study aimed to assess self-reported nonadherence and to identify potential barriers to adherence in glaucoma patients. Methods: Participants completed a 16-item questionnaire, designed to examine nonadherence rate and assess the therapy experience. Inclusion criteria stipulated treatment duration of at least 1 year. Nonadherence was defined as missing ≥5% of the prescribed pressure-lowering eye drops doses. Results: In total, 201 glaucoma patients aged 24-88 years were included. Mean treatment duration was 9.4 years. Nonadherence was reported by 30.3% of participants and 69.7% were reported to be adherent. Individuals who experienced side effects reported higher levels of nonadherence than those who did not (37.6% vs. 18.4%; P = 0.004). Eye drops with preservatives were used by 84.1% of participants, 11.9% were on combined preservative and preservative-free treatment, and 4.0% on preservative-free medication only. Self-reported nonadherence levels were 32.0%, 25.0%, and 12.5%, respectively, for each of these groups. Men reported higher rates of nonadherence than women (36.8% vs. 24.5%; P = 0.066). Age, social status, history of migration, severity of disease, and fear of blindness were not associated with significant differences in nonadherence levels. Conclusions: Nonadherence with glaucoma therapy is a significant barrier to therapeutic success for approximately one-third of patients. Nonadherence may be reduced if side effects are avoided. Preservative-free products may provide adherence benefits. The patient experience should be a key consideration when selecting appropriate treatments, to reduce nonadherence and optimize outcomes.