performance of wearers of stenfilcon a contact lenses after a refit with test lenses

Conditions: Myopia

Summary: the aim of this study is to determine if habitual or adapted wearers of stenfilcon a control contact lenses can be refit into test lenses and be successful after one week of daily wear.

this study is a prospective, multi-center, open label, bilateral, daily wear, one week dispensing study comparing performance of wearers of stenfilcon a control contact lenses after refit with test contact lenses.

Eligibility criteria:
inclusion criteria: a person is eligible for inclusion in the study if he/she: * is between 18 and 35 years of age (inclusive) * has read and signed the informed consent letter * is willing and anticipated to follow instructions and maintain the appointment schedule * habitually wears soft spherical contact lenses with a power between -1.00d to -6.00d (inclusive) for a minimum 5 days per week, 10 hours per day and anticipates no difficulty wearing contact lenses for 7 days per week, 10 hours per day. * habitually wears or is able to be adequately refit into myday sphere lenses * demonstrates an acceptable fit with the study lenses * is correctable to a distance visual acuity of 0.20 logmar (approximately 20/30) or better (in each eye) with the study contact lenses * uses digital devices, (e.g. computer, tablet, smart phone, ipad), for more than 4 hours a day, 5 days a week. * manifest cylindrical spectacle refraction does not exceed -0.75dc in either eye * has clear corneas and no active ocular disease * has a contact lens refraction that fits within the available parameters of the study lenses. exclusion criteria: a person will be excluded from the study if he/she: * is participating in any concurrent clinical research study * has a history of not achieving comfortable cl wear (5 days per week; \> 8 hours/day) * has a systemic condition that, in the opinion of the investigator, may affect the study measures * is using any systemic or topical medications that in the opinion of the investigator may affect the study measures. * presents with slit lamp findings or clinically significant anterior segment abnormalities that would contraindicate contact lens wear such as: * pathological dry eye or associated findings * significant pterygium, pinguecula, or corneal scars within the visual axis * neovascularization \> 0.75 mm in from of the limbus * giant papillary conjunctivitis (gcp) worse than grade 1 * anterior uveitis or iritis (or history in past year) * seborrheic eczema of eyelid region, seborrheic conjunctivitis * history of corneal ulcers or fungal infections * poor personal hygiene * has a known history of corneal hypoesthesia (reduced corneal sensitivity) * has a known sensitivity to the diagnostic pharmaceuticals to be used in the study * has aphakia, keratoconus or a highly irregular cornea. * has presbyopia or has dependence on spectacles for near work over the contact lenses. * has undergone refractive surgery. * is pregnant, lactating or planning a pregnancy (by verbal communication) at the time of enrollment * has participated in any other type of eye related clinical or research study within the last 7 days * is habitually using rewetting/ lubricating eye drops (more than once per day)