Biocurrent Therapy
A Promising Treatment for Dry AMD
by Dan Roberts
with additional material
by Wendy Strouse Watt, O.D.
October 26, 2005
Acuity Medical has successfully completed a proof of concept,
double-masked trial of its TheraMac™ device for the treatment of dry
age-related macular degeneration (AMD). The therapy developed from
early studies of microcurrent stimulation, with improvements in the
science and application.
Since the late 1980's, practitioners have been marketing microcurrent
stimulation devices that have not been approved for treatment of the
retina by the Food and Drug Administration (FDA). Acuity Medical,
however, has been working with the FDA, and successful completion of
the trials will allow legal marketing of TheraMac™ for use in biocurrent therapy. This is good news for patients
with dry macular degeneration, as it is one of the few studies
currently underway for treatment of that form of the disease.
This article gives complete information as provided to MD Support by
lead researcher John Jarding, O.D., in an Internet conference on
October 12, 2005. Also present were Wendy Strouse Watt, O.D. (MD
Support Professional Advisor), and Thomas McColley, President of Acuity
Medical, Inc.
Background
In 1985, Leland Michael, O.D. (Rapid City, South Dakota) and Merrill
Allen, O.D. (Purdue University, Indiana), began a ten-year study of the
treatment of age-related macular degeneration (ARMD) using biocurrent. They found that biocurrent, originally designed as a
treatment for pain, seemed to stabilize the degenerative process of the
retinal cells.
When Dr. Michael passed away in 1995, his work was taken over by John
Jarding, O.D., who began to determine which microcurrent frequencies
and waveforms would be most therapeutic for the macula. That research
led him to the development of TheraMac™.
"I have felt," Dr. Jarding told MD
Support, "that it was only appropriate to follow FDA protocol when
treating patients. Until we prove the benefits of biocurrent therapy to
the FDA, it is not appropriate to sell instruments or advertise the
benefits of biocurrent for the treatment of macular degeneration. These
are FDA rules. These are things we plan to prove or disprove to the FDA
through the trials.”
"Because there are significant differences in micro current
instruments," he explained, "none of which are FDA approved
for the treatment of macular degeneration, appropriate research in
current amounts, current frequencies, and frequency of use must be
studied. Through my work with electrical engineers and a cell
biologist, the TheraMac™ instrument has passed these items to the FDA's
satisfaction, allowing it to be used in clinical trials. I have had a
continued fear that uncontrolled use of microcurrent and unapproved
instruments would shed unfair and negative light on my work. My open
clinical studies have shown very positive results using the appropriate
current, frequency levels and frequency of use with TheraMac™ and
biocurrent. 62% of the eyes treated have gained 2 or more lines of
best-corrected visual acuity."
When asked to compare results of his recent research with the 10-year
study in which he participated with Drs. Michael and Allen, Dr. Jarding said that comparison
is difficult. The earlier research simply collected data from patients
in open label studies. Also, the studies included use of vitamins in
tandem with biocurrent therapy (aka microcurrent stimulation), which
the recent study did not. The feasibility study also used current
levels at the lower end of the therapeutic range to ensure not breaking
the double masked status. "Yet," said Dr. Jarding, "all studies showed
an improvement in vision in well over half of the patients treated."
Possible Mechanisms
Electrical currents in the wound healing range increase ATP
concentrations, promote the absorption of amino acids in tissue,
stimulate protein synthesis, and assist membrane transport of amino
acids. Nordenstom discussed the effects of relatively low-level
electric fields on the permeability of capillaries.
A review of the literature showed that the time frames associated with
minutes to one hour per treatment). The short duration of the treatment
times indicated that the healing effects tended to favor mechanisms
associated with short-term metabolic events, such as ATP synthesis,
cyclic AMP and protein kinase C activity, and calcium transport. Other
possible electrotherapy effects included: vascular dilation, changes in
capillary permeability, vascular conditioning, protein filtering,
tissue cell membrane polarization, and nervous system conditioning. It
is possible that electrotherapeutic treatments could affect cell
proliferation, cell differentiation, and tissue regeneration.
Biocurrent stimulation appears to improve the membrane permeability of
the blood vessels and the cells and allows better oxygen and nutrition
delivery to the cells and removal of by-products from the cells. An
improvement in circulation improves the functioning of the cells and
enables improved vision. There may be an improvement in cell
metabolism, ATP levels, and protein synthesis.
Development of TheraMac™
Dr. Jarding coined the name TENSMAC™ (Transcutaneous Electrical Nerve
Stimulation of the Macula) in 1997. Years of research led him to more
accurately name his procedure TESMAC™ (Transcutaneous Electrical
Stimulation of the Macula) since not only nerves were being stimulated
as the acronym suggests. Physiologically, increases in ATP (or energy)
levels, increases in metabolic activity of the cells, and protein
synthesis occurred. TESMAC™ became TheraMac™ in 2003 to reflect the
advances in development of the therapy.
How the Biocurrent Stimulation Studies Differ From Earlier Work
The results of these earlier studies, that were neither blinded nor
controlled, suggested that nutrition and electrical stimulation were
beneficial in treating all types of macular degeneration. By using
both types of treatment at the same time, the data was confounded. It
was difficult to determine whether the nutrition or the electrical
stimulation was responsible for the change in vision or how much of an
effect each had on the change in vision. These studies demonstrated the
need for more research, controlled and double-blinded studies,
treatment with electrical stimulation only, and treating one type of
macular degeneration at a time. Nevertheless, the patients achieved a
meaningful improvement in visual acuity.
The results of the feasibility study (which was controlled and
double-blinded) showed that treatment with biocurrent generated
significant improvement in visual acuity in those in the treatment
group. This was achieved while keeping the blind in place. The current
used was determined to be therapeutic (at the lowest level that would
be beneficial), without allowing any indications of receiving it so as
not to allow the patients to know if they were using the functional or
non-functional instrument. Also, the data was pure because only one
treatment was used for one type of macular degeneration, and the
changes in visual acuity were attributable to it.
How TheraMac™is Diffe
rent from Other Devices
The only instruments that are being used for macular degeneration therapy off-label are TENS devices. These have received FDA approval for the alleviation of pain, but have not been approved and found to be safe for use in retinal therapy. The TheraMac™ device was designed specifically for the treatment of AMD. It has built-in safety measures to prevent the use of current that is too high and dangerous to the retina. It has patented current and frequency levels designed specifically for the treatment of AMD. Acuity Medical has addressed the problems of poor current control and impedance that have shown to be big problems for other micro current devices. The FDA Open Label and Feasibility studies have found the TheraMac™ device to be safe and effective.
The Science Behind Biocurrent Therapy
Microcurrent stimulation describes a broad spectrum of applications.
These include TENS therapy for the alleviation of pain, cochlear
implants, therapy of Parkinson’s disease, stimulation for bladder
control, etc.
Acuity Medical maintains that treatment with TheraMac™ utilizes patented biocurrent ranges with very specific frequencies to stimulate the desired physiologic
response at the retinal level. Researchers confirm that micro current is well controlled
with good control of current impedance.
Biocurrent therapy uses very low doses of micro current. Micro current
is electrical current in the one millionth of an ampere range. This low
current has shown to stimulate the production of the active transport
enzyme, adenosine triphosphate (ATP), which facilitates the movement of
nutrition from the blood to the cell. Microcurrent also increases
membrane permeability to move substrates into and out of the cell.
Since AMD is a disease of poor circulation to the center of the retina,
the macula, an improvement of that circulation is essential in
revitalizing retinal cell function. This fact was proven in the Cheng
study of 1982.
Acuity's research has focused on determining the ideal range of current
and frequencies of biocurrent. They have found that too little current
is ineffective, as is too much current. Too much current can also be
damaging to neural cells of the retina. When testing many of the micro
current devices currently on the market for pain, Acuity researchers
found them to have a poor current control and major impedance problems.
All of these problems have been addressed with the TheraMac™ instrument
and the treatment protocol.
Clinical Trial Objectives and Endpoints
The title of the study was: A Double-Blind, Placebo-controlled,
Randomized, Feasibility Study to Evaluate the Efficacy of TheraMac™.
Although previous experience provided anecdotal support for the
efficacy of the TheraMac™ device, no well-controlled trials had been
done prior to the feasibility study. The primary purpose was to test
study procedures and conduct exploratory data analyses in anticipation
of expanding to a large-scale clinical trial. The secondary endpoint
was the efficacy of the TheraMac™ device to improve visual acuity in
patients with Dry MD. Success was defined as a significant difference
between TheraMac™ and the control group in the change in distance
visual acuity from baseline to post-treatment.
Trial Design
Subjects were patients with dry (non-bleeding) age related macular
degeneration. There were two treatment groups (active and non-active).
The patient population was 50 years of age or older, were diagnosed
with dry AMD, and had their best visual acuity between 20/40 and
20/100. The non-active group was the control group. The trial was
double-blinded or double-masked, meaning that neither the patient nor
the investigator knew who was receiving treatment and who was not
receiving treatment. Patients were assigned to either the treatment or
the control group randomly. The non-active TheraMac™ unit looked and
worked the same as the active unit, but no current was transmitted.
Trial Results
The results were significant. 26% of the treated group gained 10 or
more letters (2 or more lines on the eye chart) as opposed to 11% of
the control group. 59% of the treated group gained 5 or more letters
(one or more lines on the eye chart) compared to 11% of the control
group.
The Future
Acuity Medical is in the process of preparing for the final FDA study,
in which it will be seeking approval for the sale and use of the device
by all doctors who desire to use it. The pre-market approval study will
be conducted at approximately 10 sites, treating a total number of 300
patients. At this time, none of the sites can be identified. Acuity
Medical will notify MD Support with a list of sites and contacts as
soon as the information is ready for publication.
When asked how the approval and marketing of TheraMac™ might affect
practitioners who are already using other devices that have not been
FDA-approved for retinal therapy, Dr. Jarding issued this statement:
"Once the FDA approves the use of biocurrent and the TheraMac™ device,
the therapy and device will be made available to any eye doctor who
wishes to prescribe it. Training will be provided to the doctors and
their staff on the procedure and use of the instrument. It must be
understood that any use of an unapproved device is deemed by the FDA as
off-label use and must not be advertised as an approved therapy for
AMD. If an alternative device is used off-label, the patient must be
warned that it has not received FDA approval for efficacy and safety.
It would make sense that doctors would choose to use an approved device
over an unapproved device."
Dr. Jarding and Acuity Medical have followed procedures, process and standards that give credibility and credence to their research. Theirs is the only research to date that involves a double-blind, controlled trial, and it is currently being peer-reviewed for publication. Also, the safety of TheraMac™ has been established, and it complies with American and International standards. If the device is approved after the trials, it will be for treating macular degeneration. Other devices that are being used are approved only for treating pain and not for use around the head and eyes.
About Dry Macular Degeneration
Macular degeneration is a disorder affecting the macula, the central
part of the retina. Bruch’s membrane separates the neural network of
the circulatory network of the choroid. The retina is comprised of many
layers. The Retinal Pigment Epithelium (RPE) cells make up the inner
most layer of the retina. The RPE are supporting cells for the outer
layers of the retina and they contain melanin that gives them their
dark color and decreases light scatter within the eye. The RPE form a
blood-retinal barrier, are vital to the metabolism of Vitamin A,
transport nutrients and metabolites between the choroid and the retina,
manufacture extracellular mucopolysaccharides and lipids (which compose
drusen), remove damaged and discarded photoreceptor outer segments, and
resynthesizes photosensitive pigments.
The RPE-Bruch’s membrane complex is the area of activity in the genesis
of drusen. The narrowing of the capillary lumen and the atrophy of the
choriocapillaris at the macula is the cause of the RPE malfunction.
This causes a zone of hypoxia (decreased oxygen levels). When the RPE
are not functioning properly, they produce drusen. Bruch’s membrane
thickens with age, and accumulation of lipids interferes with
the
function of the RPE, affecting the overlying photoreceptors.
As the membrane permeability decreases and the choriocapillaris
degenerates, the lack of oxygen increases. The macular circulation
becomes further impaired, and there is inadequate blood flow to remove
the by-products from the cells. These by-products become toxic to the
photoreceptors and RPE. The circulation continues to be compromised,
the membrane permeability decreases more, RPE function decreases, RPE
cells migrate to areas of the macula with better circulation or the
cells drop out (die), and the macular degeneration worsens. If normal
retinal metabolism is not restored, more and more RPE cells will die,
and geographic atrophy will occur, creating the condition called dry
(atrophic) macular degeneration.
To see illustrations of the anatomy of the eye as discussed here, see
www.mdsupport.org/anatomy.html
About Acuity Medical
Acuity Medical, located in Brighton, Michigan, is a therapeutic
technology company that is developing treatments for all aspects of
macular disease. Since 1995 the company has been focused on development
of biocurrent therapy for dry AMD. With an increasing amount of data
demonstrating that electrical stimulation safely improves vision,
Acuity Medical has the potential with the introduction of TheraMac™ to
bring much-needed treatment and relief to dry AMD patients.
For more information about Acuity Medical, contact Tom McColley at (810) 229-5828.
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