Contact Lens Approval Process Has Similarities to Clinical Drug Trials

Contact Lenses are regulated by the Food andalso pry a little more into the amount of drugs
Drug Administration (F.D.A.) as Class 3 Medicalneeded to be effective in treatment and what
Devices. Class 3 medical devices are defined bytime intervals are needed to administer the
the FDA as those that support or sustain humanmedication.
life, are of substantial importance in preventingPhase 3 studies are what brings a new drug to
impairment of human health, or which present athe corner pharmacy. Phase 3 trials may base
potential, unreasonable risk of illness or injury.tentative approval on only several hundred
Class 3 medical devices require the highest levelpatients, and typically no more than 2000-3000
of evidence for market approval which is aare in this phase. For you, that does mean a 1 in
process to evaluate safety and effectiveness10,000 lethal effect may not be known initially, or
before the product can be brought to market.some other surprises may not be uncovered for
Clinical studies, scientific documentation, andseveral years. In Phase 3 patients are split into
reviews are required. There can also be postgroups with one group receiving placebos (no
marketing surveillance studies after a new contactactive medication) and another group receives the
lens is released to look for further problems.actual medication, Researchers typically don't
Prescription drugs require a similar but much moreknow who is getting what until the end of the
involved process before they reach the marketstudy. Occasionally, it becomes so evident that a
place.drug is saving lives or vision that the study is
A press release from the National Eye Institute instopped as it is not ethical to deprive the patients
2008 stated a phase one gene therapy clinical trialreceiving placebos of the full benefits of the new
showed promising results for a blinding diseasedrug. The Woman's Health Initiative study on
known as a congenital form (present at birth) ofhormone replacement therapy for menopause
Optic Atrophy. The retinal pigment epithelium iswas an example of this. The study was
the layer of the tissue lining the back of the eye,terminated early when it was determined that
the retina, that nourishes the rod and cone cellshormone therapy increased the risk of breast
we see with. A mutation in a retinal pigmentcancer.
epithelium gene causes these cells to respondPhase 4 is where the good, the bad, and the ugly
very poorly to light and results in loss of vision.comes out. This is also called the Post Marketing
Frequently we see news on gene therapy andSurveillance Phase. Phase 4 trials involve the long
are led to believe everything will be cured by interm safety monitoring where the 1 in a million
short order. Patients in the study received aproblems start to be seen over time. Also the
sub-retinal injection to replace the defective geneinteractions with other medications may become
in areas of the retina that were still relativelymore evident, and strange reactions specific to an
healthy. Each patient had visual impairment thatindividual may appear. Long term effects like the
had been present since birth due to the defectivediet drug that caused heart problems may show
gene. Over a 90-day period there was significantup after a number of years.
improvement in vision. Day vision was improvedOur Fort Collins office has taken part in several
by 50-fold and night vision by 63,000-foldoptometrist clinical studies with contact lenses.
compared to levels prior to treatment. RestoredThese are somewhat like the phase 3 clinical trials
vision was localized to the area of treatment infor medications. A lens may be studied by eye
the eye that received the injection. We tend todoctors on 500-600 patients prior to approval.
think of new drugs and medical devices asWhile there is no such thing as a placebo lens, a
overnight miracles but researchers have beencontact lenses that has been approved in the past
working for 15 years to get to this point. Thecan be used on one eye as a comparison control.
new generation of 30 day wear contact lensesIt a lot of fun to be involved in these emerging
actually started with research done in the 1970's.contact lens products but also a lot of record
All new prescription drugs and medical deviceskeeping, and when patients don't keep their
face the funding and regulatory structures thatappointments the stipulations are pretty rigid
are required to pass the requirements forabout dropping them from the study. Generally
approval. While this process is frustrating andwe do not expect the same type of serious
fraught with problems, if you spend a little timecomplications with contact lenses that can be
reading about the equivalent processes andseen with new medications.
equivalent oversight agency in China, you will gainOne final bit of information. Sometimes things
a greater appreciation for the system we doworks out in odd ways. While drugs may have
have in place.undergone all 4 phases and have approval for
Clinical trials for prescription drugs proceed in fourspecific conditions, that does not restrict doctors
phases over a period of years and millions offrom using medications "off label" in ways they
dollars. Actually there is a new phase zero buthave not been studied and approved for.The Food
since it is still in transition we will cover only the 4and Drug Administration regulates drugs and
main phases.medical devices, not Doctors. Currently, the
The first testing of drugs in humans as referredstandard of care for certain eye infections is "off
to as phase one. Typically this involves healthylabel eye drops." It would be considered
individuals in a group less than 50. The main goalsubstandard care to use the FDA approved
of phase one trials are the to make sure theremedication in these special cases. This a very
are no glaring safety issues and gain someuncommon occurrence indicative of some weak
understanding of how the drug works and ispoint in the system where clinical experience is
processed in the body. Normally, a small (20-50)ahead of the curve. Someday there will be a way
group of healthy volunteers will be selected.to account for these situations. Until then, we will
Phase 2 trials are mostly just an extension ofcontinue to do the best with what we know
phase one with several hundred patients. Theytoday.