In vitro and in vivo Evaluation of the Efficacy and Safety of Powder Hydroxypropylmethylcellulose as Nasal Mucosal Barrier.

INTRODUCTION: Insufflation of powder hydroxypropylmethylcellulose (pHPMC) in the nose has been proven an effective barrier in subjects with rhinitis in many clinical studies. We conducted additionally in vitro and in vivo experiments to address outstanding efficacy and safety issues. METHODS: We used an experimental setup to demonstrate the inhibition of the diffusion of allergen extracts (house dust mite, Japanese cedar, Ragweed, Timothy grass) and pollutants (particulate matter 2.5 µm, PM2.5). Safety of pHPMC when insufflated in the airways of rats was assessed in 24 animals which were sacrificed; tissue sections from lungs, brain and liver were made 1, 24 and 48 hrs after pHPMC inhalation and compared to those of control animals. RESULTS: pHPMC acted as an effective barrier to diffusion of both the liquid allergen extracts and of PM2.5 into the agar covered slides: the quantities of the other tested allergens ranged between <0.5% and 14% of the quantities diffused in the void slides after 6 hrs. The quantity of PM2.5 penetrating the agar was reduced by 94%. Histological photomicrographs did not reveal any evidence of inflammation at 1, 24 and 48 hrs after pHPMC insufflation. CONCLUSION: Use of pHPMC should be viewed as a barrier enforcing measure against inhalatory ambient intruders.

Methyl-cellulose powder for prevention and management of nasal symptoms.

INTRODUCTION: HPMC-p, an inert micronized powder form of hydroxy-propyl-methyl-cellulose, when insufflated nasally, provides a natural barrier against pollen allergens and noxious agents. This overview assesses the efficacy and safety of this patented powder product and delivery system without an analogue among the cellulose derivatives. Areas covered: Twenty-six studies with HPMC-p were critically appraised to obtain an updated characteristic of the product. Most studies assessed the efficacy of HPMC-p as a nasal barrier enforcing measure: one experimental setup evaluated its ability to prevent or delay the diffusion of allergen through it, two clinical studies used allergen provocation tests, and the remaining relied on clinical criteria in open real world or placebo controlled designs. Two studies checked if HPMC-p could enhance the efficacy of drugs applied nasally to treat local symptoms. The studies, using either nasal allergen challenge or natural exposure of patients to environmental allergen, support the hypothesis that HPMC-p possesses barrier enforcing properties. Also, acute and clinical experiments indicated that intra-nasal application of HPMC-p following local relief medications enhances their ability to suppress symptoms and reduces their long-term use. Expert commentary: Nasal insufflation of HPMC-p provides a mucosal barrier, reducing the nasal symptoms and enhancing the effects of local relief medications.

In vitro activity of an aqueous allicin extract and a novel allicin topical gel formulation against Lancefield group B streptococci.

BACKGROUND: Studies have shown the efficacy of intra-partum antibiotics in preventing early-onset group B streptococcal sepsis. This approach results in a high intra-partum antibiotic use. Worryingly, the same antibiotics used in prophylaxis are also first-line treatment for neonatal sepsis, and antibiotic exposure in the peri-natal period has been shown to be a risk factor for late-onset serious bacterial infections and allergic disease. Antibiotic exposure in the peri-natal period is becoming a major public health issue; alternative strategies are needed. Garlic has been traditionally used to treat vaginal infections. Allicin is the main antibacterial agent isolated from garlic. OBJECTIVES: The aim of the study was to investigate the in vitro activity of a novel allicin extract in aqueous and gel formulation against 76 clinical isolates of Lancefield group B streptococci (GBS). METHODS: MICs and MBCs of allicin were determined for 76 GBS isolates by agar dilution and microtitre plate methods. Killing kinetics were determined for a selected 16 of the 76 strains. Agar diffusion tests were compared for allicin liquid and gel (500 mg/L). RESULTS AND CONCLUSIONS: MICs and MBCs of allicin liquid were 35 to 95 mg/L and 75 to 315 mg/L, respectively. Time/dose kill curves produced a 2-3 log reduction in cfu/mL within 3 h and no detectable growth at 8 and 24 h. A novel 500 mg/L allicin gel produced an average zone size of 23+/-6 mm compared with 21+/-6 mm for allicin in water. Aqueous allicin is bactericidal against GBS isolates and maintains activity in a novel gel formulation.

Preventing airborne infection with an intranasal cellulose powder formulation (Nasaleze travel).

A total of 52 volunteers were recruited to take part in a dual-centered, randomized, blinded study so investigators could determine whether the level of airborne infection could be significantly reduced in patients randomly assigned to treatment with either Nasaleze cellulose extract alone or a combination of Nasaleze cellulose and powdered garlic extract (PGE). One puff into each nostril was recommended, and volunteers who developed an infection while traveling were told to use at least 3 puffs per nostril until symptoms were reduced. This study took place over an 8-wk period across Finland and the United Kingdom between November 2006 and March 2007. Volunteers were instructed to use a 5-point scale to assess their health and to record infectious episodes and symptoms in a daily diary. The activetreatment group (Nasaleze cellulose with PGE) experienced significantly fewer infections than the control group (20 vs 57; P<.001) and far fewer days on which an infection was obviously present (126 d in the active group vs 240 d in the control group; P<.05). Consequently, volunteers in the active group were less likely to pick up an airborne infection when PGE was added to this novel cellulose extract. Volunteers in the control group were much more likely to report more than 1 infectious episode over the treatment period or to endure longer periods of infection. The investigators concluded that the combination Nasaleze Travel formulation significantly reduced the number of airborne infections to which volunteers were exposed while traveling.

Preventing the common cold with a vitamin C supplement: a double-blind, placebo-controlled survey.

One hundred sixty-eight volunteers were randomized to receive a placebo or a vitamin C supplement, two tablets daily, over a 60-day period between November and February. They used a five-point scale to assess their health and recorded any common cold infections and symptoms in a daily diary. Compared with the placebo group, the active-treatment group had significantly fewer colds (37 vs 50, P<.05), fewer days challenged virally (85 vs 178), and a significantly shorter duration of severe symptoms (1.8 vs 3.1 days, P<.03). Consequently, volunteers in the active group were less likely to get a cold and recovered faster if infected. Few side effects occurred with the active treatment, and volunteers reported greatly increased satisfaction with the study supplement compared with any previous form of vitamin C. This well-tolerated vitamin C supplement may prevent the common cold and shorten the duration of symptoms. Volunteers were generally impressed by the protection afforded them during the winter months and the general acceptability of the study medication.