Two studies on manuka honey for blepharitis

1. Randomised masked trial of the clinical safety and tolerability of MGO Manuka Honey eye cream for the management of blepharitis.

BMJ Open Ophthalmol. 2017 Aug 4;

Craig JP1, Wang MTM1, Ganesalingam K1, Rupenthal ID1, Swift S2, Loh CS1, Te Weehi L1, Cheung IMY1, Watters GA1.

Abstract

OBJECTIVE:
To assess the clinical safety and tolerability of a novel MGO Manuka Honey microemulsion (MHME) eye cream for the management of blepharitis in human subjects. 

METHODS AND ANALYSIS:
Twenty-five healthy subjects were enrolled in a prospective, randomised, paired-eye, investigator-masked trial. The MHME eye cream (Manuka Health New Zealand) was applied to the closed eyelids of one eye (randomised) overnight for 2 weeks. LogMAR visual acuity, eyelid irritation symptoms, ocular surface characteristics and tear film parameters were assessed at baseline, day 7 and day 14. Expression of markers of ocular surface inflammation (matrix metalloproteinase-9 and interleukin-6) and goblet cell function (MUC5AC) were quantified using impression cytology at baseline and day 14. 

RESULTS:
There were no significant changes in visual acuity, eyelid irritation symptoms, ocular surface characteristics, tear film parameters and inflammatory marker expression during the 2-week treatment period in treated and control eyes (all p>0.05), and measurements did not differ significantly between eyes (all p>0.05). No major adverse events were reported. Two subjects experienced transient ocular stinging, presumably due to migration of the product into the eye, which resolved following aqueous irrigation. 

CONCLUSION:
The MHME eye cream application was found to be well tolerated in healthy human subjects and was not associated with changes in visual acuity, ocular surface characteristics, tear film parameters, expression of markers of inflammation or goblet cell function. The findings support future clinical efficacy trials in patients with blepharitis. 

2. Preclinical development of MGO Manuka Honey microemulsion for blepharitis management.

BMJ Open Ophthalmol. 2017 Aug 7

Craig JP1, Rupenthal ID1, Seyfoddin A1,2, Cheung IMY1, Uy B3, Wang MTM1, Watters GA1, Swift S3.

Abstract

OBJECTIVE:
To evaluate the in vitro antimicrobial effects of cyclodextrin-complexed and uncomplexed Manuka honey on bacteria commonly associated with blepharitis, and in vivo rabbit eye tolerability of a cyclodextrin-complexed methylglyoxal (MGO) Manuka Honey microemulsion (MHME). 

METHODS AND ANALYSIS:
In vitro phase: Bacterial growth inhibition was assessed by area under the growth curve (AUC) for Staphylococcus aureus, and the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for S. aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa with cyclodextrin-complexed and uncomplexed Manuka honey were determined. In vivo phase: Six rabbits were administered 20 µL of MHME (at 1:10 dilution) to the right eye (treated) and 20 µL of saline to the left eye (control) daily, for 5 days. Tear evaporation, production, osmolarity, lipid layer, conjunctival hyperaemia and fluorescein staining were assessed daily, before and 15 min after instillation. 

RESULTS:
In vitro phase: The relative AUC for cyclodextrin-complexed Manuka honey was lower than that of uncomplexed honey at both 250 and 550 mg/kg of MGO (both p <0 .05="" aeruginosa.="" all="" and="" assessed="" aureus="" both="" but="" changes="" control="" cyclodextrin-complexed="" either="" epidermidis="" eyes="" for="" had="" honey="" in="" lower="" mbc="" mic="" no="" not="" observed="" or="" p.="" p="" parameters="" phase:="" s.="" significant="" than="" the="" treated="" uncomplexed="" vivo="" were="">0.05). 

CONCLUSION:
Overall, antimicrobial potency of cyclodextrin-complexed Manuka honey was greater than uncomplexed honey. No significant immediate or cumulative adverse effects were observed with MHME application on rabbit eyes, supporting future conduct of clinical safety and tolerability trials in human subjects.