RCS - PureTech Health PLC - PRTC: New LYT-200 AML Data + Update at ASH

Puretech HealthAnnouncement

03/11/2025 14:00

For best results when printing this announcement, please click on link below:
https://newsfile.refinitiv.com/getnewsfile/v1/story?guid=urn:newsml:reuters.com:20251103:nRSC8166Fa&default-theme=true

RNS Number : 8166F  PureTech Health PLC  03 November 2025

PureTech's Founded Entity Gallop Oncology to Present New Data from Ongoing
Phase 1b Trial of LYT-200 in Relapsed/Refractory Acute Myeloid Leukemia (AML)
at the American Society of Hematology (ASH) Annual Meeting

 

LYT-200 continues to demonstrate strong evidence of clinical activity,
survival benefit and a highly favorable safety profile in heavily pretreated
relapsed/refractory AML patients, both as a monotherapy and in combination
with standard of care

Compelling responses achieved in population with diverse tumor molecular
subtypes

 

Data continue to mature and will be presented during ASH 2025; topline
efficacy readout and overall survival data expected in Q4 2025 and 1H 2026,
respectively

 

PureTech Health plc (https://puretechhealth.com/)  (Nasdaq: PRTC, LSE: PRTC)
("PureTech" or the "Company"), a hub-and-spoke biotherapeutics company
dedicated to giving life to science and transforming innovation into value,
today announced that new data from its ongoing Phase 1b clinical trial
evaluating LYT-200, a first-in-class anti-galectin-9 monoclonal antibody, in
relapsed/refractory acute myeloid leukemia (AML) will be shared on December
6(th), 2025, during the 67th Annual American Society of Hematology (ASH)
Annual Meeting in Orlando, Florida, by its Founded Entity Gallop Oncology. The
accepted abstract reflects data as of July 8, 2025, and additional analyses
based on a later data cut-off are expected to be presented during the ASH
meeting.

 

The ongoing, open-label, dose-ranging trial is evaluating LYT-200 both as a
monotherapy and in combination with the standard-of-care (SOC) regimen of
venetoclax (VEN) and hypomethylating agents (HMA) in a very vulnerable
population. All participants in the trial have previously been treated with
SOC (median prior lines of treatment: 3; range: 1-7), and their disease had
either returned or failed to respond.

 

The data submitted to ASH reflect efficacy and safety findings for 31
participants in the monotherapy arm and 39 participants in the combination arm
who received LYT-200 weekly at doses ≥7.5mg/kg. As a monotherapy, treatment
with LYT-200 resulted in 1 marrow complete response (CR) and 3 partial
responses (PRs). Notably, one PR in the monotherapy arm was maintained for 24
months as of the data cut off in an individual whose disease previously
progressed following five prior rounds of treatment with SOC. When
administered in combination with VEN/HMA, LYT-200 treatment resulted in 12
CRs, 1 PR, and 1 morphological leukemia-free state (MLFS). Importantly, CRs
were achieved in this cohort across a diverse range of tumor subtypes,
including KRAS, NRAS, HRAS, and JAK2 mutations, in patients who were
previously fully refractory to SOC.

 

When evaluating patients with AML, a CR is the primary goal of treatment and
means that no leukemia cells are detectable in the blood, fewer than 5% blasts
remain in the bone marrow, and blood counts have returned to normal. Achieving
a CR is generally associated with improved outcomes, including longer overall
survival. A PR reflects a significant reduction in leukemia burden, with at
least a 50% decrease in blasts, while an MLFS indicates that there are no
leukemia cells visible and fewer than 5% blasts in the marrow, though blood
counts have not yet recovered. While SOC in this advanced relapsed/refractory
population typically achieves CR rates of 6-12% and median overall survival is
less than 2.5 months, 1  LYT-200 has demonstrated a >30% CR rate in the
combination cohort as of the data cut off, underscoring its potential to serve
as a meaningful new treatment option.

 

Across all dose levels and treatment arms, LYT-200 was well tolerated. No
dose-limiting toxicities were reported, and there were no LYT-200-related
serious adverse events, discontinuations, or deaths. The most common adverse
events potentially related to LYT-200 were mild and transient.

 

"The combination of this level of efficacy with a clean safety profile
underscores the importance of advancing LYT-200 into its next phase of
development, especially given the high relapse rates and poor survival
outcomes in AML," said Luba Greenwood, JD, Chief Executive Officer of Gallop
Oncology. "As survival data mature, we believe they could add another
compelling dimension to LYT-200's potential clinical profile for patients with
relapsed/refractory AML, including those who have failed VEN/HMA or have
mutations associated with poorer prognosis, where the need for new therapies
remains urgent."

 

PureTech intends to share further matured data at ASH, including updated
efficacy across dose levels, as well as survival and
pharmacokinetic/pharmacodynamic data. Topline efficacy data are expected in
the fourth quarter of 2025, with topline survival data anticipated in the
first half of 2026. PureTech intends to engage with regulatory authorities to
advance LYT-200 into a Phase 2 trial.

 

About AML and MDS

Acute myeloid leukemia (AML) is an aggressive blood cancer characterized by
the rapid growth of abnormal myeloid cells in the bone marrow and blood. It is
the most common form of acute leukemia in adults, with a five-year survival
rate of less than 30%. Despite available therapies, many patients relapse or
fail to respond, and outcomes are especially poor in the relapsed/refractory
setting.

 

Myelodysplastic syndromes (MDS) are a group of rare blood cancers in which the
bone marrow does not produce enough healthy blood cells. High-risk MDS often
progresses to AML and is associated with limited treatment options and poor
survival.

 

Together, AML and high-risk MDS represent areas of urgent unmet medical need
where new therapies with improved efficacy and durability are critically
needed. Importantly, the incidence of AML is increasing and the market is
expected to grow to $6 billion by 2030, underscoring the scale of the
opportunity to bring forward more effective therapies. 2 

 

About LYT-200

LYT-200 is a fully human IgG4 monoclonal antibody targeting galectin-9, a key
oncogenic driver and potent immunosuppressor in cancer. It is being developed
for the potential treatment of hematological malignancies and solid tumors
with otherwise poor survival rates. In an ongoing acute myeloid leukemia (AML)
trial, LYT-200 has demonstrated clinical activity and disease stabilization in
heavily pretreated patients, both as a monotherapy and in combination with
standard-of-care therapy.

 

LYT-200 has been granted Fast Track
(https://news.puretechhealth.com/news-releases/news-release-details/puretech-receives-fda-fast-track-designation-lyt-200-acute)
and Orphan Drug
(https://news.puretechhealth.com/news-releases/news-release-details/puretech-receives-orphan-drug-designation-lyt-200-acute-myeloid)
designations from the U.S. Food and Drug Administration (FDA) for the
treatment of acute myeloid leukemia, underscoring the high unmet need in this
disease and the potential for LYT-200 to serve as a meaningful therapeutic
option.

 

About Gallop Oncology

Gallop is a clinical-stage biopharmaceutical company committed to transforming
treatment paradigms for hematologic malignancies. Guided by science, designed
for patients, and driven to deliver meaningful outcomes, Gallop is advancing a
novel approach where efficacy, safety, and durability converge. Its lead
candidate, LYT-200, leverages a dual mechanism of action facilitated by
galectin-9 -direct tumor cell killing coupled with potent immune
activation-offering a differentiated strategy to address some of the most
challenging cancers. LYT-200's lead indication is acute myeloid leukemia
(AML).

 

Gallop Oncology was founded by and is currently a wholly-owned subsidiary of
PureTech Health plc (Nasdaq: PRTC, LSE: PRTC), a hub-and-spoke biotherapeutics
company dedicated to giving life to science. PureTech's innovative R&D
engine powers Founded Entities like Gallop, advancing highly promising
medicines to patients in a capital-efficient manner. For more information,
please visit www.galloponcology.com (https://www.galloponcology.com) and
www.puretechhealth.com (https://www.puretechhealth.com) .

 

About PureTech Health

PureTech Health is a hub-and-spoke biotherapeutics company dedicated to giving
life to science and transforming innovation into value. We do this through a
proven, capital-efficient R&D model focused on opportunities with
validated pharmacology and untapped potential to address significant patient
needs. This strategy has produced dozens of therapeutic candidates, including
three that have received U.S. FDA approval. By identifying, shaping, and
de-risking these high-conviction assets, and scaling them through dedicated
structures backed by external capital, we accelerate their path to patients
while creating sustainable value for shareholders.

 

For more information, visit www.puretechhealth.com or connect with us on X
(formerly Twitter) @puretechh.

 

Cautionary Note Regarding Forward-Looking Statements

This press release contains statements that are or may be forward-looking
statements within the meaning of the Private Securities Litigation Reform Act
of 1995. All statements contained in this press release that do not relate to
matters of historical fact should be considered forward-looking statements,
including without limitation those related to the LYT-200 development program
and development plans, its potential benefits to patients, plans for
discussions with regulatory authorities, the further development of the
program, future presentation of additional data from the program and our
future prospects, developments and strategies. The forward-looking statements
are based on current expectations and are subject to known and unknown risks,
uncertainties and other important factors that could cause actual results,
performance and achievements to differ materially from current expectations,
including, but not limited to, those risks, uncertainties and other important
factors described under the caption "Risk Factors" in our Annual Report on
Form 20-F for the year ended December 31, 2024, filed with the SEC and in our
other regulatory filings. These forward-looking statements are based on
assumptions regarding the present and future business strategies of the
Company and the environment in which it will operate in the future. Each
forward-looking statement speaks only as at the date of this press release.
Except as required by law and regulatory requirements, we disclaim any
obligation to update or revise these forward-looking statements, whether as a
result of new information, future events or otherwise.

 

PureTech
Public Relations
publicrelations@puretechhealth.com (mailto:publicrelations@puretechhealth.com)

Investor Relations
IR@puretechhealth.com (mailto:IR@puretechhealth.com)

UK/EU Media
Ben Atwell, Rob Winder

+44 (0) 20 3727 1000
puretech@fticonsulting.com (mailto:puretech@fticonsulting.com)

US Media
Justin Chen
jchen@tenbridgecommunications.com (mailto:jchen@tenbridgecommunications.com)

 

 1  Maiti, N. A., Rausch, N. C. R., Cortes, N. J. E., Pemmaraju, N. N., Daver,
N. N. G., Ravandi, N. F., Garcia-Manero, N. G., Borthakur, N. G., Naqvi, N.
K., Ohanian, N. M., Short, N. N. J., Alvarado, N. Y., Kadia, N. T. M.,
Takahashi, N. K., Yilmaz, N. M., Jain, N. N., Kornblau, N. S., Bravo, N. G.
M., Sasaki, N. K., . . . Konopleva, N. M. Y. (2020). Outcomes of relapsed or
refractory acute myeloid leukemia after frontline hypomethylating agent and
venetoclax regimens. Haematologica, 106(3), 894-898.
https://doi.org/10.3324/haematol.2020.252569

 2  Grand View Research, Acute Myeloid Leukemia Treatment Market Size, Share
& Trends Analysis Report By Disease, By Treatment (Chemotherapy, Targeted
Therapy, Immunotherapy), By Route of Administration, By End Use, By Region,
And Segment Forecasts, 2025 - 2030

 

This information is provided by Reach, the non-regulatory press release distribution service of RNS, part of the London Stock Exchange. Terms and conditions relating to the use and distribution of this information may apply. For further information, please contact
rns@lseg.com (mailto:rns@lseg.com)
 or visit
www.rns.com (http://www.rns.com/)
.

RNS may use your IP address to confirm compliance with the terms and conditions, to analyse how you engage with the information contained in this communication, and to share such analysis on an anonymised basis with others as part of our commercial services. For further information about how RNS and the London Stock Exchange use the personal data you provide us, please see our
Privacy Policy (https://www.lseg.com/privacy-and-cookie-policy)
.   END  NRAUUVBRVSUARAA



            Copyright 2019 Regulatory News Service, all rights reserved