New
research links Ozempic to a rare side effect that may affect eye health.
- Two
large studies from the University of Southern Denmark suggest that the
diabetes medication Ozempic doubles the risk of developing NAION, a rare
but serious condition that damages the optic nerve.
- Drawing
on comprehensive data from Danish and Norwegian health registers, the
studies validate earlier concerns raised in a smaller American study.
- While
the absolute risk remains low, researchers suggest the findings should
guide discussions between doctors and patients about the benefits and
risks of treatment with Ozempic.
Two research teams
conducted separate studies using different methods to analyze all Danish users
of Ozempic.
These new register-based
studies from SDU corroborate a concern previously highlighted in a
smaller American study earlier last year.
The American study found
that Ozempic more than doubles the risk of non-arteritic anterior ischemic optic neuropathy (NAION), a
rare condition that damages the optic nerve.
In the first Danish study, researchers analyzed data from 424,152 Danes
with type 2 diabetes and found that Ozempic doubles the risk of developing
NAION.
This condition, caused
by a sudden loss of blood flow to the optic nerve, can result in severe and
permanent vision loss.
In the second
Danish study, which is yet to be published in a peer-reviewed
journal, researchers categorized patients into two groups: those treated with
Ozempic and those who received alternative treatments.
This study focused on a
smaller, more specific group of patients with type 2 diabetes.
This research also
revealed that the risk of developing NAION doubles for those taking Ozempic.
However, the researchers emphasized that their
findings are not intended to discourage diabetes patients from continuing their
treatment with Ozempic.
While untreated diabetes
can cause various eye complications, these are generally less severe but more
common than the optic nerve damage associated with NAION.
Lead author Anton Pottegård, M.Sc. Pharm., Ph.D., Dr. Med. from the
Institute of Health Services Research, University of Southern Denmark, spoke
to Medical News Today.
“The
core finding I guess is the simple fact that we see more cases of NAION, a very
rare but serious disease of the optic nerve, among users of semaglutide than
among users of other antidiabetic medications. This finding is very consistent
across all the analyses we’ve tried coming up with. While we don’t know why
this happens, it seems the drug increases the risk of this disease.”— Professor
Anton Pottegård
A representative from
Novo Nordisk, the manufacturer of Ozempic, told MNT that “NAION
is a very rare eye disease, and it is not an adverse drug reaction for the
marketed formulations of semaglutide (Ozempic, Rybelsus and Wegovy) as per the
approved labels.”
“After a thorough
evaluation of the studies from the University of Southern Denmark and Novo
Nordisk’s internal safety assessment, Novo Nordisk is of the opinion that the
benefit-risk profile of semaglutide remains unchanged,” they said.
“While
both studies showed a roughly doubling of relative risk, the absolute risk and
absolute number of people affected is very low. This aligns with the very low
annual incidence of this rare disorder. One of the studies found that 2 people
per 10,000 patients treated with semaglutide in a year developed NAION versus 1
out of every 10,000 in the comparator group, concluding that the absolute risk
is very low. The studies did not demonstrate a causal relationship between
semaglutide and NAION.”— Novo Nordisk
“The short-term
implications are few,” Pottegård explained, “in the sense that the vast
majority of patients should continue their treatment and that this clearly does
not change the overall risk-benefit profile of the drug.”
“That said, there is the
specific short-term implication in that patients that have experienced eye
problems that could be NAION should probably contact their physician and, if
confirmed, should stop using the drug,” Pottegård said.
“Patient
safety is a top priority for Novo Nordisk, and we take all reports about
adverse events from use of our medicines very seriously. This also relates to
eye conditions, which are well-known comorbidities for people living with
diabetes. Any decision to start treatment with prescription-only medicines
should be made in consultation with a healthcare professional who should do a
benefit-risk evaluation for the patient in question, weighing up the benefits
of treatment with the potential risks.”— Novo Nordisk
Three experts, who were
not involved in these studies, spoke to Medical
News Today.
Benjamin
Bert, MD, board certified ophthalmologist at MemorialCare Orange
Coast Medical Center in Fountain Valley, CA, said that these studies “presented
are very interesting as this is still a fairly new class of medication, having
only been around for a few years.”
“Our knowledge of the
full extent of the medication’s side effects is still being discovered. In
these papers, the researchers identify a significant increase in NAION in a
large population of diabetic patients who are undergoing treatment with
Ozempic,” Bert said.
“While this finding is
concerning, especially given that there’s no treatment for NAION at this time,
each individual’s risk and benefit of treatment with Ozempic needs to be
discussed,” Bert explained.
Mark A.
Anton, MD, medical director at Slimz Weightloss, agreed, saying,
“for patients, it’s crucial to balance the potential benefits of semaglutide
with these risks.”
“It emphasizes the
importance of regular monitoring and open communication with healthcare
providers to tailor treatment plans to individual needs and risks.”
Howard Krauss, MD, surgical neuro-ophthalmologist and director
of Pacific Neuroscience Institute’s Eye, Ear & Skull Base Center at
Providence Saint John’s Health Center in Santa Monica, CA, said that “type 2
Diabetes Mellitus (T2DM) is one of several risk factors in the occurrence of
NAION and one presumes that the influence of T2DM on the incidence of NAION may
increase with the duration and severity of the disease.”
“As the authors note:
“our study cannot claim a causal relationship,” Kraus highlighted.
Krauss also warned of
the potential harm of “scaring physicians or patients away from a medication
which reduces the morbidity and mortality associated with T2DM.”
This is because NAION is
rare to begin with, and even with an increased incidence, it remains a rare
condition.
Krauss highlighted the
potential harm done when the media publish stories about rare side effects
“leading to unfounded fear in the public mind.”
“A
retrospective review of this nature should be published with editorial caveats
to minimize public misperception. A report of this nature should lead to
scientific testing of a hypothesis which may be proposed, that semaglutide may
trigger NAION, but at this time it is nothing more than a hypothesis.”— Howard
Krauss, MD
However, reporting rare
side effects and informing the public about them is an important aspect of
pharmacovigilance.
NAION as a potential
side effect of semaglutide, the active ingredient in Ozempic, has already been
under review, and the new findings will be incorporated into ongoing
evaluations.
Pottegård noted that “if
the regulators find this to be a likely causal link, the many emerging drugs in
this class should be scrutinized for the same effect.”
“Also, this should lead
to research into the actual prevalence of the problem (which might be
underrecorded using the highly specific diagnostic requirements used in our
studies), research into the underlying mechanism (currently unknown) and
research into the identification of patients at risk of this adverse effect,”
he said.