Antibiotic drop instillation during continuous contact lens wear

INTERVENTION: Twice daily instillation of TOBREX (tobramycin 0.3%) antibiotics drops (two drops on waking and two drops prior to sleep each night) during continuous lens wear compared to a control group using saline drops over a three month period CONDITION: Contact lens wear PRIMARY OUTCOME: To investigate the safety of twice daily antibiotic drop instillation during day and night continuous wear. Primary safety variables include ocular discomfort, history, ocular examination, bulbar and limbal ocular redness, palperbral conjunctival redness and roughness, corneal and conjunctival staining. History (including medical and general health) will be recorded on the Participant History File at all visits. Ocular examination using slit‐lamp biomicroscopy will be carried out at baseline and every visit. SECONDARY OUTCOME: No emergence of bacterial resistance or over‐growth of fungus on ocular surface. To be assessed by ocular and throat swabs and aseptic collection of worn lenses. Emergence of bacterial resistance will be examined by assessing the numbers of bacteria that show resistance to the antibiotic over time using standard "minimum inhibitory concentration" assays. Emergence of fungal overgrowth will be examined by assessing the percentage of microbial colonies that are fungi of the total microbial counts. INCLUSION CRITERIA: Be able to read and comprehend English and give informed consent as demonstrated by signing a record of informed consent; Be at least 18 years old; Be willing to comply with the wearing and clinical trial visit schedule as directed by the investigator; Have ocular health findings considered to be "normal" and which would not prevent the participant from safely wearing contact lenses; Have vision correctable to at least Snellen Visual Acuity of 6/12 (metres) or better in each eye with contact lenses, which means the participant can read within 3 lines of the nominal performance for human distance visiion (i.e. 6/6). Be experienced at wearing contact lenses