Delaying but not blocking AMT-130,
uniQure’s emerging gene therapy to slow Huntington’s disease progression, the U.S. Food
and Drug Administration (FDA) “strongly recommended” that the company conduct a
full-blown, Phase III clinical trial, rather than assess an application for drug
approval based on an earlier trial that showed historic efficacy.
The news came in a March 2 uniQure
press release, relying on official minutes from the company’s January 30
high-priority meeting with the FDA about the AMT-130 program. The drug has been
shown to slow the progression of by HD symptoms by as much as 75 percent.
As discussed below, this action
reflects the more conservative trend of at least parts of the FDA under the
Trump administration.
Based on the meeting minutes, the
FDA has maintained its new decision that data from the earlier AMT-130 Phase
I/II trial, using the global Enroll-HD patient database as a comparison, cannot be used as
primary evidence for a drug application, the release stated.
The company added: “The FDA strongly
recommended uniQure conduct a prospective, randomized, double-blind, sham
surgery-controlled study. uniQure intends to continue engaging with the FDA
regarding Phase III development considerations and plans to request a […]
meeting in the second quarter of 2026 to further discuss potential study design
approaches.”
A prospective, randomized,
double-blind study is a standard clinical trial in which neither patients nor
researchers know who receives the drug. A sham (pretend) surgery, which uniQure
did on a few clinical trial participants early in the Phase I/II study, will
now be required as a placebo, which is standard in most clinical trials.
Relying on Enroll-HD data had taken the place of the sham surgery, which
uniQure had stopped doing for ethical reasons. Injecting AMT-130 into the brain
involves a twelve-plus-hour brain operation.
uniQure’s plans
“While we did not reach alignment on
a submission pathway based on the Phase I/II data, we believe the totality and
durability of our data warrant continued substantive dialogue” with the FDA
regarding “regulatory flexibility,” uniQure CEO Matt Kapusta stated. “We remain
committed to engaging with the FDA to determine a clear, scientifically
grounded, and efficient path forward for AMT-130. We are deeply grateful for
the resilience and support of the Huntington’s disease community and remain
committed to standing with patients and their families.”
“Regulatory flexibility” refers to
FDA programs that, for example, allow potential accelerated drug approval.
uniQure had previously pursued that.
Based on its studies so far, which
include three years of analysis, uniQure plans to share a four-year analysis,
“which we expect to complete in the third quarter of 2026,” Daniel Leonard, the
company’s director of global patient advocacy, wrote in a letter e-mailed to
the HD community. “We believe the extended follow-up will provide additional
insight into both the durability and the magnitude of the effects of AMT-130.”
Removing bias from the study
Last September, uniQure had reported
that AMT-130 demonstrated a 75 percent slowing in the progression of HD over a
three-year period.
However, in crisis under the Trump administration, the FDA backtracked on its word regarding the firm’s plans to submit its
application in early 2026, prompting 48,000-plus people to sign two petitions
to the agency asking to keep its promise.
On February 24, a top uniQure
scientist presented an updated analysis of AMT-130 at the 21st Annual HD
Therapeutics Conference.
David Margolin, M.D., Ph.D., uniQure’s vice president for clinical
development, gave the first scientific presentation at the Therapeutics
Conference. He addressed the question, raised by the FDA, regarding the use of
data from Enroll-HD, instead of a placebo, in the AMT-130 clinical trial.
“We relied on an external comparator
cohort, which is selected from participants in the Enroll- HD Natural History
Study, which has advantageous characteristics as a comparator,” Dr. Margolin
explained. However, whereas the AMT-130 clinical trial takes MRI measurements
of the brain, including the crucial striatum, Enroll-HD participants do not.
To mitigate the “potential bias”
from this difference, uniQure used a statistical technique known as “propensity
score matching,” Dr. Margolin stated. As he explained, this involves finding in
Enroll-HD individuals similar to those in the uniQure trial and including them
as controls.
The volume of the striatum (which
demonstrates the loss of brain tissue in HD) as a factor in the AMT-130 trial
“becomes moot,” Dr. Margolin continued. Other patient characteristics from
Enroll-HD “can fully substitute” for that measure, such as neuropsychological
testing and measurements of a person’s involuntary movements, he said.
“This analysis supports the validity
of the three-year efficacy results,” Dr. Margolin concluded. uniQure will
publish results of the AMT-130 trial in a scientific journal.
Dr. David Margolin (above) displaying a slide demonsrating AMT-130's efficacy in slowing HD progression and (below) enjoying down time at the Therapeutics Conference (photos by Gene Veritas, aka Kenneth P. Serbin)
‘At the precipice’ of effective
treatments
Held at the Parker hotel in Palm Springs, CA, the HD Therapeutics Conference
concluded on February 26. It is sponsored by CHDI Foundation, Inc., the largest private backer of the quest for HD therapies.
Like potential remedies in other HD
programs, such as Roche’s tominersen,
AMT-130 lowers (reduces) the amount of defective huntingtin protein.
“We have multiple shots on goal in
the huntington-lowering arena, things like uniQure,” CHDI Chief Scientific
Officer Robert Pacifici, Ph.D., told me in an interview on February 27. “While
it's true that none of them have made it out the other end with a positive
ruling in a pivotal Phase III trial, we're at the precipice of the types of
signals that will indicate that there is a clinically meaningful benefit by
lowering huntingtin.”
Such benefit must be confirmed
through a Phase III trial or conditional approval by the FDA.
This “exciting” development
encourages other companies to invest in late-state trials, Dr. Pacifici added,
noting that lowering huntingtin hits at the root causes of HD.
Dr. Pacifici at the conclusion of the Therapeutics Conference (photo by Gene Veritas)
A ‘more conservative’ FDA
Cristina Sampaio, M.D., Ph.D.,
CHDI’s chief medical officer, joined the foundation in 2011 after serving on
two entities in the European Medicines Agency (EMA), the FDA’s counterpart in
Europe.
In a February 25 interview, Dr.
Sampaio, who advises companies on their clinical trial programs, observed that
companies other than uniQure have faced changes in course with the FDA.
Under the Trump administration, she
said, the FDA become “more conservative,” especially in the Center for Biologics Evaluation and Research,
the unit in charge of evaluating drugs such as AMT-130. News reports have also
noted the conservative trend.
FDA ‘ping pong’ not healthy
At the same time, Dr. Sampaio stated
that changes in the FDA’s approval process are “problematic” for uniQure and
other firms.
“Companies rely on what they discuss
with FDA,” Dr. Sampaio said. “This for them is vital. It's how they define
their projects, it's how they define how long it will take to the market, it's
how they define their budget, how much it will cost.”
Changing positions from one day to
the next “creates a lot of uncertainty to the market,” she observed. “This ping
pong of FDA is not healthy.”
As news organizations have reported,
changes in leadership at the FDA, firings, and the exit of mid- and high-level
managers have created “uncertainty” and “turmoil” at the agency, Dr. Sampaio
said.
More susceptible to politics
Whereas decisions about drugs in
Europe tend to be more “democratic,” the FDA is “hierarchical,” making it more
susceptible to politics, Dr. Sampaio observed.
Even so, she added, outside of
normal lobbying, “there was no evidence” until now that political influence was
affecting the FDA.
“But until these big changes with
the Trump administration, the FDA was very respected as an independent body,”
Dr. Sampaio asserted.
External comparisons are good
science
Dr. Sampaio noted that the uniQure
AMT-130 clinical trial program began in 2019 as an exploratory venture, mainly
to test for safety. As time passed and the personnel at the firm changed, the
goals for AMT-130 became “more ambitious.”
“But this was not pre-planned,” she
said. “And this is a weakness. That said, I believe they have been as careful
as they can be, given the circumstances, and given the data they have.” The 17
patients about which data have been revealed is also a “small” number, she
acknowledged.
The decision to use Enroll-HD as a
comparison was also first “pushed by the FDA,” Dr. Sampaio noted, albeit under
the previous administration.
Use of Enroll-HD as an “external
comparator” is good science, Dr. Sampaio emphasized, noting that in
oncology a similar technique has been used for more than a decade.
AMT-130 data moving in the right
direction
Significantly, all of the AMT-130
data go “in the same direction,” showing improvement in the symptoms, she said.
“This is very powerful.”
If AMT-130 were granted accelerated
approval, it would be conditional, with the drug having to be removed from the
market if problems emerged, Dr. Sampaio explained. Accelerated approval would
also require ongoing study of the drug for safety and efficacy.
Dr. Margolin’s presentation at the
therapeutics conference resolved scientific doubt regarding the volume of the
striatum, Dr. Sampaio said. “This alleviated the concern that the population in
this trial was not representative.”
Dr. Sampaio (right) with Dr. Hoa Huu Phuc Nguyen of Ruhr University Bochum, Germany (photo by Gene Veritas)
Some think AMT-130 needs more work
Blair Leavitt, M.D., a veteran HD researcher and professor of medicine at the
University of British Columbia, also weighed in on AMT-130 and the FDA. Dr.
Leavitt is the co-founder and co-editor-in-chief of the Journal of
Huntington’s Disease.
Dr. Leavitt’s lab received funding
from uniQure to conduct research.
“We tested in our mouse model of
Huntington's disease and showed benefits of the uniQure approach in that mouse
model,” he explained in a February 26 interview at the Therapeutics Conference.
He thinks that the uniQure clinical trial was “designed primarily to show the
safety and tolerability of the approach and the agent in individuals with
Huntington's disease, and it absolutely did that.”
The AMT-130 program has opened “a
whole field of gene therapy and gene editing approaches, which is incredibly
exciting for our field,” Dr. Leavitt added.
However, Dr. Leavitt thinks more
work needs to be done on AMT-130. “I would disagree with some people who have
suggested [that the work done so far] is sufficient to prove efficacy,” he said, adding that “a proper
controlled trial” is ultimately needed. In effect, this was what the FDA has
now recommended to uniQure.
Regarding the 75 percent slowing of
symptoms with AMT-130, Dr. Leavitt observed that “we're talking about a decline
in all of the patients, on average, but a less decline. That certainly is
positive. That might be the best we can hope for with many of our therapies,
but ultimately, it's not a complete reversal of symptoms.”
Uncertainty at FDA ‘bad for all’
Dr. Leavitt, as a Canadian citizen,
declined to comment on the political impact of the Trump administration on the
FDA.
“But I do believe it is a difficult
time for drug development,” he said. “The FDA is really the premier regulator
for most of the world, and uncertainty at the FDA leads to uncertainty in drug
development, and that's bad for all of us.”
Such uncertainty “is the last thing
we need at this point, because we are on the precipice of a number of
therapies, and I'm sure we're going to have efficacy.”
Others firms’ interactions with the
FDA
Veteran HD researcher Jang-Ho Cha, M.D., Ph.D., the chief science and medical officer of Latus Bio,
addressed a question from the audience after his February 24 presentation about
the company’s HD program.
Ed Wild, M.D., Ph.D.,wanted to know whether Latus had a strategy for engaging
with the FDA and its Center for Biologics Evaluation and Research to obtain
drug approval. Dr. Wild also asked whether an industry consortium could help
“to at least extract some firm guidance?”
“Yes, we have a strategy to engage
with them,” Dr. Cha responded. Latus hopes to soon submit an Investigational
New Drug (IND) application.
“At this point, we will wait until
we have our IND package to show them everything we’ve got,” Dr. Cha continued.
“I’m not sure exactly, if we asked a question from the FDA, we would get an
answer that we could rely on exactly at this point. We are watching with a lot
of interest other companies who are having interactions with the FDA, because
it’s relevant to all of us.”
Will the truth conquer all?
Dr. Pacifici offered a concluding
reflection regarding the FDA.
“In terms of the interaction between
the companies and the regulators, I guess I'm a bit of an optimist in this
regard,” Dr. Pacifici told me. “I truly believe that politics and money and all
of the other perverse things that surround us, notwithstanding, that at the end
of the day, the truth conquers all.”
“I think that these are scientific
people,” he said. “I think that they're going to look at the body of data and
evidence, and eventually I think they're going to make the very best decision
to get things out as quickly and as safely as possible to the patients who so
desperately need these treatments.”
For additional coverage, visit
HDBuzz.
Next time: Dr. Pacifici’s overview
of the conference and his video interview with me.