FLOSI (willofocon A) Rigid Gas Permeable Spherical, Aspherical, Toric, and Bifocal Contact Lenses are indicated for daily wear correction of refractive ametropia (myopia, hyperopia, astigmatism and presbyopia) in aphakic and non-aphakic persons with non-diseased eyes. The lens may be disinfected using a chemical disinfection system only.
Device Story
Flosi (wilofocon A) is a rigid gas permeable (RGP) contact lens available in spherical, aspherical, toric, and bifocal designs. The lens acts as a refractive element to correct vision in aphakic and non-aphakic patients. It is a hemispherical shell made of wilofocon A polymer, containing D & C Green No. 6 as a color additive. The device is intended for daily wear and requires chemical disinfection. It is prescribed by eye care professionals. By altering the refractive path of light entering the eye, the lens compensates for myopia, hyperopia, astigmatism, or presbyopia, potentially improving visual acuity for the patient.
Clinical Evidence
Clinical study of 122 eyes (110 completed, 12 discontinued) over 3 months. Average patient age 37. Primary endpoints included slit-lamp findings, symptoms/problems/complaints (SPCs), keratometry, refraction, and visual acuity. Slit-lamp findings were within expected ranges for RGP wearers. No patients experienced a drop in visual acuity greater than one line. Average wearing time was 14.9 hours. No adverse reactions or treatments required. Study concluded the lens is safe for daily wear.
Technological Characteristics
Material: wilofocon A (hydrophobic, water content <1%). Oxygen permeability (Dk): 26 x 10^-11 (cm²/sec)(ml O2/ml x mmHg). Refractive index: 1.44. Hardness (Shore): 89. Dimensions: 6.5-11.5 mm diameter, 0.05-0.70 mm center thickness, 6.50-9.00 mm base curve. Powers: -20.00 to +20.00 D. Contains D & C Green No. 6. Chemical disinfection required.
Indications for Use
Indicated for daily wear correction of refractive ametropia (myopia, hyperopia, astigmatism, presbyopia) in aphakic and non-aphakic persons with non-diseased eyes.
Regulatory Classification
Identification
A rigid gas permeable contact lens is a device intended to be worn directly against the cornea of the eye to correct vision conditions. The device is made of various materials, such as cellulose acetate butyrate, polyacrylate-silicone, or silicone elastomers, whose main polymer molecules generally do not absorb or attract water.
Submission Summary (Full Text)
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K 974636
ﺍﯾﮏ ﮐﮯ ﮐﺎ ﺭﻗﺒﮧ 197
ുക്കും.
അവലംബം
MAR 30 1998
#### COMPREHENSIVE SUMMARY III.
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K974636
# NAME AND USE OF DEVICE
:
| Device Generic Name: | wilofocon A |
|----------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| Device Trade Name: | Flosi rigid gas permeable contact lens |
| Indications: | Flosi rigid gas permeable contact lenses are<br>Indicated for daily wear correction of visual<br>acuity In aphakic and not-aphakic persons<br>with non-diseased eyes who are nearsighted<br>(myopic), farsighted (hyperopic), presbyopic<br>or who have corneal astigmatism. |
| Alrperm Ranges: | Chord diameter 6.5 to 11.5 mm<br>Center thickness 0.05 to 0.70 mm<br>Base Curve 6.50 to 9.00 mm<br>Powers -20.00 to +20.00 diopters |
| Cleaning and Disinfection: | The Fiosi rigid gas permeable contact lens<br>must be disinfected using only a chemical (not<br>heat) disinfection system as recommended. |
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K97463k
# VI. DEVICE CHARACTERISTICS
The FLOSI (wilofocon A) Rigid Gas Permeable Contact Lons Is available as a spherical, aspherical, and astigmatic (toric) lens. The lens material, willofocon A, is sphencer, asphonour, and assigment which contains D & C Green No: 6 as a color additive. The FLOS (willofocon A) Contact Lens is a hemispherical shell of the following dimensions:
## LENS PARAMETERS AVAILABLE
| •Diameter | 6.5 to 11.5 mm |
|--------------------------------------------------|----------------------------------------------------------------------------------------------|
| •Center Thickness | |
| for Low Minus Lens: | 0.05 to 0.30 mm |
| for Plus Lens: | 0.10 to 0.70 mm |
| •Base Curve | 6.50 to 9.00 mm |
| •Powers | -20.00 to +20.00 Diopters |
| •Aspheric Lens Eccentricity | -1.5 to 1.5 |
| Oblate to Prolate | |
| Feripheral Curves | 0.1 to 10 mm. Flatter or Steeper than<br>Base Curve |
| •Toric Lens | |
| Axis | 1 to 180 degrees in 1 degree steps |
| Cylinder power | 0.50 to 4.00 Diopters |
| The physical/optical properties of the lens are: | |
| •Specific Gravity | 1.25 |
| •Refractive index (589 nm at 25°C) | 1.44 |
| •Light Transmittance | |
| Clear (370-760 nm) | 93% |
| Tinted (D & C Green No. 6) (380-780 nm) | 87% |
| •Surface Character | Hydrophobic |
| •Wetting Angle (CLMA Method) | 23.0 ± 2 |
| •Water Content (Gravimetric method at 22°C) | <1% |
| •Oxygen Permeability | Dk 26 x 10-11 at 35°C<br>(cm²/sec) (ml 02 /ml x mmHg) Polarographic method<br>of Fatt (1990) |
| •Hardness (Shore) | 89 |
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K974636
#### SUMMARY OF STUDIES FLOSI (wilofocon A) Rigid Gas Permeable Contact Lens
### IIIB. PRECLINICAL STUDIES
1. Systemic Injection Test In Mice
The test is based on the FDA guidelines entitled "Testing Guidelines for Class II Contact Lenses, April 1989", and the United States Pharmacopeia XXII, National Formulary XVII. None of the test and control animals exhibited overt signs of toxicity at any of the observation points and hence the test material is considered non-toxic.
2. Eye Irritation Test in Rabbits
The test is based on the FDA guidelines entitled "Testing Guidelines for Class III Contact Lenses, April 1989". The extract of test contact lenses was evaluated for the potential to produce ocular irritation over a 72 hour period. The test article did not cause any significant irritation to the ocular tissues of the test animals.
3. Tissue Culture-Agar Overlay Cytotoxicity Assay
The assay is based on that described in USP and National Formulary. The contact lens blanks did not cause any obsevable cytotoxic effects when tested according to the procedures outlined in the study report and is therefore considered non-cytotoxic.
Based on the results of the preclinical testing it is reasonable to assume that the Flosi (wilofocon) Rigid Gas Permeable Contact Lens Polymer is nontoxic.
#### IIIC. CLINICAL STUDIES
All eves enrolled in the study were accounted for. A total of 122 eyes were enrolled in the study. A total of 110 eyes completed a minimum of three months of contact lens wear, 0 eyes were incomplete and 12 eyes were discontinued. The largest number of patients enrolled in this study (92.7%) were previous wearers of rigid gas permeable contact lenses. The average age was 37 years. During the three-month course of this study there were a total of 428 scheduled and 38 unscheduled eye visits.
Slit-Lamp: There was a total of 99 reports of Grade 1 SLFs of which the largest number was for comeal staining (77 reports or 18% of all visits). The staining at the follow-up visits was nearly all of the type three and nine o'clock staining, which was also present at the initial visit. The next most common slit lamp findings were for injection, which included 15 reports or 3.5% of the visits. There were five reports of grade 2 findings, all for staining and which were resolved by lens changes.
The total number of slit-lamp findings were within expecteds for wearers of an RGP contact lens. The large number of reports for corneal staining can be
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K974636
attributed to the fact that most patients were previous rigid lens wearers who entered the study with three and nine o'clock staining. During the time that lenses were worn by the discontinued patients there were no slit lamp findings reported.
SPCs: There were a total of 135 reports of symptoms, problems or complaints for the 356 eye visits during the three-month course of this study. The largest number of complaints (8.7%) was for variable vision, followed by lens awareness (6.2%). All symptoms, problems or complaints were reduced over time. None of the categories for symptoms, problems, and complaints can be considered outside of the normal expecteds for a rigid gas permeable contact lens.
Keratometry: The majority of the eye meridians (90.4%) showed no change to 0.50 diopters change over the course of this investigation. Changes of 1.00 diopter or less were found in 98.6 percent of the eye meridians. The number of changes were nearly equal for those who had increased or decreased power which resulted in an average change of 0.08 diopters flattening. In the three patients who experienced a change of greater than 1.00 diopter, two eye meridians showed a decrease of 1.25 diopters and one eye meridian showed an increase of 1.25 diopters. The changes in keratometry were generally low and may be attributed to adaptation to a new lens type or usual clinical measurement variation. The three patients who showed changes in one eye meridian of 1.25 diopters all had no change in their normal visual acuity of 20/20 and no significant signs or symptoms.
Refraction: The majority of the eyes (99.1%) showed no change to 1.00 diopters change over the course of this investigation. The number of spherical and cylindrical changes were nearly equal for those who had increased or decreased power, which resulted in an average change of near zero. In the two patients who experienced a change of greater than 1.00 diopter, one (306) showed a spherical change in the left eye of 1.50 diopters. One patient (505) showed a cylindrical decrease in both eyes of 1.50 diopters, which was attributed to a better fit of the test contact lens than was the case for the lens worn prior to the study. The changes in refraction were generally low and may be attributed to a better fitting lens or usual clinical measurement variation. The three eyes that showed changes of 1.50 diopters all had no change in their normal visual acuity of 20/20 and no significant signs or symptoms. For the patients who discontinued, the 12 test eyes showed no change to 0.50 diopters change over the course of this investigation. The number of spherical and cvlindrical changes were nearly equal for those who had increased or decreased power. The changes in refractive sphere and cylinder were generally low and may be attributed to normal variation in the findings.
A comparison was made between the best corrected visual Visual Acuity: acuity at the initial examination to the visual acuity when wearing contact lenses at the final examination. There were no patients who experienced a drop of visual acuity that was greater than one line during the course of this study. Two patients had reduced visual acuity both initially and at the end of this study and
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K974636
merit comment. Visual acuity results when wearing Flosi Rigid Gas Permeable Contact Lenses during the course of this investigation were found to be within expecteds. No patients experienced a drop of visual acuity that was greater than one line.
The average wearing time achieved at the end of the study was 14.9 hours.
#### Conclusion:
There were no eyes that experienced adverse reactions, SLFs requiring treatment or SPCs requiring treatment. The FLOSI rigid gas permeable contact lens was shown to be worn safely by all patient eyes in this study including those that completed (110 eyes) and discontinued (12 eyes) the study.
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Image /page/6/Picture/1 description: The image is a seal for the Department of Health & Human Services USA. The seal is circular and contains the department's logo in the center. The logo is a stylized representation of a human figure with three arms, symbolizing health, human services, and the USA. The text "DEPARTMENT OF HEALTH & HUMAN SERVICES USA" is arranged around the perimeter of the circle.
Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850
MAR 30 1998
Dr. William Platt Futuristic Design Associates 1 Avalon Road Mount Vernon, OH 43050
Re: K974636
> Trade Name: Flosi (Wilofocon A) Rigid Gas Permeable Contact Lenses for Daily Wear (Spherical, Aspheric, Toric and Bifocal) Clear and Tinted (with D&C Green #6) Regulatory Class: II
Product Code: 86 HQD Dated: March 11, 1998 Received: March 12, 1998
Dear Dr. Platt:
We have reviewed your Section 510(k) notification of intent to market the devices referenced above and we have determined the devices are substantially equivalent (for the indications for use stated in the enclosure) to devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act). You may, therefore, market the devices, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.
If your devices are classified (see above) into either class II (Special Controls) or class III (Premarket Approval), it may be subject to such additional controls. Existing major regulations affecting your devices can be found in the Code of Federal Regulations, Title 21, Parts 800 to 895. A substantially equivalent determination assumes compliance with the current Good Manufacturing Practice requirements, as set forth in the Quality System Regulation (QS) for Medical Devices: General regulation (21 CFR Part 820) and that, through periodic (QS) inspections, the Food and Drug Administration (FDA) will verify such assumptions. Failure to comply with the GMP regulation may result in regulatory action. In addition, FDA may publish further announcements concerning your devices in the Federal Register. Please note: this response to your premarket notification submission does not affect any obligation you might have under sections 531 through 542 of the Act for devices under the Electronic Product Radiation Control provisions, or other Federal laws or regulations.
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Page 2 - Dr. William Platt
This letter will allow you to begin marketing your devices as described in your 510(k) premarket notification. The FDA finding of substantial equivalence of your devices to a legally marketed predicate device results in a classification for your devices and thus, permits your devices to proceed to the market.
If you desire specific advice for your devices on our labeling regulation (21 CFR Part 801 and additionally 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4613. Additionally, for questions on the promotion and advertising of your devices, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21 CFR 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its internet address "http://www.fda.gov/cdrh/dsmamain.html".
Sincerely yours,
A Ralph Rosenthal
A. Ralph Rosenthal, M.D. Director Division of Ophthalmic Devices Office of Device Evaluation Center for Devices and Radiological Health
Enclosure
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510(k) Number: K974636
Application Number:
Device Name: FLOSI (wilotocon A) Rigld Gas Permeable Spherical, Aspherical, Toric, and Bifocal Contact Lenses
Indications for use:
FLOSI (willofocon A) Rigid Gas Permeable Spherical, Aspherical, Toric, and Bifocal Contact Lenses are indicated for dally wear correction of refractive ametropla (myopla, hyperopla, astigmatism and presbyopla) In aphakic and non-aphakic persons with non-diseased eyes. The lens may be disinfected using a chemical disinfection system only.
(PLEASE DO NOT WRITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)
| Concurrence of CDRH, Office of Device Evaluation (ODE) | |
|--------------------------------------------------------|---------|
| (Division Sign-Off) | |
| Division of Ophthalmic Devices | |
| 510(k) Number | K974636 |
| Prescription Use | <div style="display:inline-block;">✓</div> | OR | Over-The-Counter Use |
|----------------------|--------------------------------------------|----|--------------------------|
| (Par 21 CFR 801.109) | | | (Optional Format 1.2.96) |
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