Health Rounds: Hormone delivery via skin patch may ease prostate cancer treatment side effects

Eisai

11/02/2025 19:55

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    By Nancy Lapid
       Feb 11 (Reuters) - Hello, Health Rounds Readers! Today
we feature something old and something new that could advance
treatment of serious diseases. A skin patch delivery of a
hormone used for years to treat menopausal women may ease the
treatment of prostate cancer for some men. We also report on a
diagnostic discovery that could one day lead to earlier
treatment of Alzheimer's disease. 
    
    Via-the-skin drug delivery eases prostate cancer treatment
    When prostate cancer patients need therapy to reduce male
hormone levels, delivering some of the treatment via a patch on
the skin may be just as effective as traditional means of
administration with fewer side effects, according to a mid-stage
study.
    Prostate cancer cells usually require male androgen
hormones, such as testosterone, to grow. Androgen deprivation
therapy (ADT) employs drugs that block the androgens’ “pathway”
to receptor proteins on cancer cells, along with so-called
luteinizing hormone-releasing hormone (LHRH) drugs that are
injected or implanted to lower the testicles’ production of
testosterone. 
    Side effects of the treatments include hot flashes, fatigue,
memory problems, and bone density loss.
    In the new trial, being presented at the 2025 ASCO
Genitourinary Cancers Symposium in San Francisco, 79 patients
with prostate cancer all received androgen receptor pathway
inhibitor drugs. In addition, they were randomly assigned to
receive either LHRH drugs or a transdermal patch containing
estradiol, a form of the female hormone estrogen.
    Transdermal estradiol, currently used for menopausal hormone
therapy, is a potentially attractive alternative approach to
ADT, said study leader Dr. Nick James of the Institute of Cancer
Research, The Royal Marsden NHS Foundation Trust, in London.
    It suppresses testosterone without estrogen depletion; it
increases bone density; it’s inexpensive; and it avoids the
blood clot risk associated with oral estrogen, he explained.
    Within six months, 61% of patients in each arm were
responding well to treatment, as assessed by their blood levels
of prostate specific antigen. 
    Patients using the estradiol patches had a lower rate of hot
flashes than those on LHRH drugs - 5% versus 24% - and a lower
rate of high blood pressure - 5% compared with 17%. 
    Enlargement of breast tissue was more common in the
estradiol patch group, however. 
    It will be some time before the researchers can assess
whether the patches were non-inferior to the LHRH drugs in terms
of metastasis-free survival, or length of time without the
disease spreading.
    They noted that in two earlier trials, estradiol patches
were equivalent to LHRH in rates of androgen suppression,
superior at improving metabolic parameters, quality of life, and
bone density, and non-inferior to LHRH in achievement of
metastasis-free survival among men with locally advanced
disease.
    Estradiol patches could be particularly attractive to
patients who are on an LHRH drug and are troubled by side
effects like hot flashes, James said. 
    They also have appeal from a cost standpoint, he added.
    “This sort of repurposing of an older, cheap drug is an
important way to improve outcomes, separate from developing new
drugs,” he said.
    
    Biomarker test finds Alzheimer's pathology earlier
    Years before clumps of tangled tau proteins show up on brain
scans of patients with Alzheimer's disease, an experimental test
can detect small amounts of the clumping protein in
cerebrospinal fluid, researchers reported in Nature Medicine.
    Patients with Alzheimer’s disease with few or no tau
neurofibrillary tangles in the brain gain more from current
therapies compared to patients with advanced tau tangles, the
researchers noted. Currently approved medicines, Leqembi from
Biogen  BIIB.O  and Eisai  4523.T  and Eli Lilly’s  LLY.N 
Kisunla, target amyloid plaques in the brain, but tau is widely
believed to be a contributor to the disease and a target of much
current research. 
    “Our test identifies very early stages of tau tangle
formation – up to a decade before any tau clumps can show up on
a brain scan,” study leader Thomas Karikari of the University of
Pittsburgh said in a statement. 
    “Early detection is key to more successful therapies for
Alzheimer’s disease since trials show that patients with
little-to-no quantifiable insoluble tau tangles are more likely
to benefit from new treatments than those with a significant
degree of tau brain deposits.”
    Karikari’s team identified a core region of the tau protein
that is necessary for neurofibrillary tangle formation, and
further identified a sequence of amino acids that are
characteristic of clumping-prone tau proteins.
    In particular, two places on the protein can yield useful
clues to the status of early-stage tau aggregation that could
potentially be reversed, if appropriate interventions are
developed, they said.
    “A large percentage of people who have brain amyloid-beta
deposits will never develop dementia,” said Karikari. 
    "Early detection of tangle-prone tau could identify the
individuals who are likely to develop Alzheimer’s-associated
cognitive decline and could be helped with new generation
therapies.”

 (Reporting by Nancy Lapid; editing by Bill Berkrot)
 ((Nancy.Lapid@thomsonreuters.com))