April 29, 2026 12:00 am EDT

SHANGHAI, China & JERSEY CITY, NJ – APRIL 29, 2026 – Shanghai Henlius Biotech, Inc.
(2696.HK), and Organon (NYSE: OGN) today announced the European Commission (EC) has granted marketing authorization
for POHERDY^® (pertuzumab) 420 mg/14 mL injection for intravenous use, the first and only approved
biosimilar to PERJETA (pertuzumab) in Europe, for all indications of the reference product.¹

“As the first, and currently the only, pertuzumab biosimilar in Europe, the EC’s approval of POHERDY
marks an important milestone in expanding access to treatments for patients with certain HER2-positive breast
cancers, particularly as breast cancer is the most commonly diagnosed cancer among women in the European
Union,” said Joe Azzinaro, Vice President, Global Commercial Lead Biosimilars, at Organon.^2,3
“Organon’s growing global portfolio of biosimilars reinforces our ongoing commitment to supporting
the sustainability of health care systems while advancing women’s health through access to quality
medicines.”^3,4

“Building on POHERDY’s FDA approval in the United States as the country’s first pertuzumab
biosimilar, this EU approval further expands our growing portfolio of approved biosimilar medicines in markets
around the world and is a testament to our strong collaboration with Organon,” said Ping Cao, Chief Business
Development Officer and Senior Vice President of Henlius. “Guided by our commitment to scientific excellence
and product quality, we are working to expand access to additional treatment options for the benefit of patients and
the health care system.”

In Europe, POHERDY is indicated in combination with trastuzumab and docetaxel for the treatment of adults with
HER2-positive metastatic or locally recurrent unresectable breast cancer, who have not received prior anti-HER2
therapy or chemotherapy for metastatic disease. POHERDY is also indicated for use in combination with trastuzumab
and chemotherapy as (i) neoadjuvant treatment of adults with HER2-positive, locally advanced, inflammatory, or early
stage breast cancer at high risk of recurrence and (ii) adjuvant treatment of adults with HER2-positive early breast
cancer at high risk of recurrence.

POHERDY was approved based on the review of a comprehensive data package, which included structural and functional
analytical data, clinical pharmacokinetic data, and comparative clinical studies demonstrating that POHERDY is a
biological medicine highly similar to the reference product based on a totality of evidence, including analytical,
pharmacokinetic, efficacy, safety, and immunogenicity data (the intrinsic ability of proteins and other biological
medicines to cause an immune response).⁵

In 2022, Henlius entered into a license and supply agreement with Organon, granting Organon the exclusive
commercialization rights to several biosimilars, including POHERDY. The agreement covers exclusive global
commercialization rights except for China.⁶

About POHERDY^® (pertuzumab-dpzb) in the U.S.

POHERDY is indicated for:

• Use in combination with trastuzumab and docetaxel for the treatment of adults with HER2-positive metastatic breast cancer who have not received prior anti-HER2 therapy or chemotherapy for metastatic disease.
• Use in combination with trastuzumab and chemotherapy for:
  • The neoadjuvant treatment of adults with HER2-positive, locally advanced, inflammatory, or early stage breast cancer (either greater than 2 cm in diameter or node positive) as part of a complete treatment regimen for early breast cancer.
  • The adjuvant treatment of adults with HER2-positive early breast cancer at high risk of recurrence.

SELECTED SAFETY INFORMATION (Based on U.S. Label)

LEFT VENTRICULAR DYSFUNCTION and EMBRYO-FETAL TOXICITY

• Pertuzumab products can cause subclinical and clinical cardiac failure manifesting as decreased left ventricular ejection fraction (LVEF) and congestive heart failure (CHF). Evaluate cardiac function prior to and during treatment. Discontinue POHERDY treatment for a confirmed clinically significant decrease in left ventricular function.
• Exposure to pertuzumab products can cause embryo-fetal death and birth defects. Advise patients of these risks and the need for effective contraception.

CONTRAINDICATIONS

POHERDY is contraindicated in patients with known hypersensitivity to pertuzumab products or to any of its
excipients.

WARNINGS AND PRECAUTIONS

Left Ventricular Dysfunction
Pertuzumab products can cause left ventricular
dysfunction, including symptomatic heart failure. Decreases in LVEF have been reported with drugs that block HER2
activity, including pertuzumab products.

Assess LVEF prior to initiation of POHERDY and at regular intervals during treatment to ensure that LVEF is within
normal limits. If the LVEF declines and has not improved, or has declined further at the subsequent assessment,
consider permanent discontinuation of POHERDY and trastuzumab.

In the pertuzumab-treated patients with MBC in CLEOPATRA, left ventricular dysfunction occurred in 4% of patients,
and symptomatic left ventricular systolic dysfunction (LVSD) (congestive heart failure) occurred in 1% of patients.
Patients who received prior anthracyclines or prior radiotherapy to the chest area may be at higher risk of
decreased LVEF or left ventricular dysfunction.

In patients receiving pertuzumab as a neoadjuvant treatment in combination with trastuzumab and docetaxel in
NeoSphere, LVEF decline >10% and a drop to <50% occurred in 8% of patients, and left ventricular dysfunction
occurred in 3% of patients. LVEF recovered to ≥50% in all of these patients.

In patients receiving neoadjuvant pertuzumab in TRYPHAENA, LVEF decline >10% and a drop to <50% occurred in 7%
of patients treated with pertuzumab plus trastuzumab and fluorouracil, epirubicin, and cyclophosphamide (FEC)
followed by pertuzumab plus trastuzumab and docetaxel, 16% of patients treated with pertuzumab plus trastuzumab and
docetaxel following FEC, and 11% of patients treated with pertuzumab in combination with docetaxel, carboplatin, and
trastuzumab (TCH). Left ventricular dysfunction occurred in 6% of patients treated with pertuzumab plus trastuzumab
and FEC followed by pertuzumab plus trastuzumab and docetaxel, 4% of patients treated with pertuzumab plus
trastuzumab and docetaxel following FEC, and 3% of patients treated with pertuzumab in combination with TCH.
Symptomatic LVSD occurred in 4% of patients treated with pertuzumab plus trastuzumab and docetaxel following FEC, 1%
of patients treated with pertuzumab in combination with TCH, and none of the patients treated with pertuzumab plus
trastuzumab and FEC followed by pertuzumab plus trastuzumab and docetaxel. LVEF recovered to ≥50% in all but 1
patient.

In patients receiving neoadjuvant pertuzumab in BERENICE, in the neoadjuvant period, LVEF decline ≥10% and a drop
to <50% as measured by ECHO/MUGA assessment occurred in 7% of patients treated with pertuzumab plus trastuzumab
and paclitaxel following dose-dense doxorubicin and cyclophosphamide (ddAC) and 2% of patients treated with
pertuzumab plus trastuzumab and docetaxel following FEC. Ejection fraction decreased (asymptomatic LVD) occurred in
7% of patients treated with pertuzumab plus trastuzumab and paclitaxel following ddAC and 4% of the patients treated
with pertuzumab plus trastuzumab and docetaxel following FEC in the neoadjuvant period. Symptomatic LVSD (New York
Heart Association [NYHA] Class III/IV Congestive Heart Failure) occurred in 2% of patients treated with pertuzumab
plus trastuzumab and paclitaxel following ddAC and none of the patients treated with pertuzumab plus trastuzumab and
docetaxel following FEC in the neoadjuvant period.

In patients receiving adjuvant pertuzumab in APHINITY, the incidence of symptomatic heart failure (NYHA Class III/IV)
with a LVEF decline ≥10% and a drop to <50% was 0.6%. Of the patients who experienced symptomatic heart
failure, 47% of pertuzumab-treated patients had recovered (defined as 2 consecutive LVEF measurements above 50%) at
the data cutoff. The majority of the events (86%) were reported in anthracycline-treated patients. Asymptomatic or
mildly symptomatic (NYHA Class II) declines in LVEF ≥10% and a drop to <50% were reported in 3% of
pertuzumab-treated patients, of whom 80% recovered at the data cutoff.

Pertuzumab products have not been studied in patients with a pretreatment LVEF value of <50%; a prior history of
CHF; decreases in LVEF to <50% during prior trastuzumab therapy; or conditions that could impair left ventricular
function such as uncontrolled hypertension, recent myocardial infarction, serious cardiac arrhythmia requiring
treatment, or a cumulative prior anthracycline exposure to >360 mg/m² of doxorubicin or its
equivalent.

Embryo-Fetal Toxicity

Based on its mechanism of action and findings in animal studies, pertuzumab products can cause fetal harm when
administered to a pregnant woman. Pertuzumab products are HER2/neu receptor antagonists. Cases of oligohydramnios
and oligohydramnios sequence manifesting as pulmonary hypoplasia, skeletal abnormalities, and neonatal death have
been reported with use of another HER2/neu receptor antagonist (trastuzumab) during pregnancy.

Verify the pregnancy status of females of reproductive potential prior to the initiation of POHERDY. Advise pregnant
women and females of reproductive potential that exposure to POHERDY in combination with trastuzumab during
pregnancy or within 7 months prior to conception can result in fetal harm, including embryo-fetal death or birth
defects. Advise females of reproductive potential to use effective contraception during treatment and for 7 months
following the last dose of POHERDY in combination with trastuzumab.

Infusion-Related Reactions

Pertuzumab products can cause serious infusion reactions, including fatal events.

In CLEOPATRA, on the first day, when only pertuzumab was administered, infusion-related reactions occurred in 13% of
patients, and <1% were Grade 3 or 4. The most common infusion reactions (≥1%) were pyrexia, chills, fatigue,
headache, asthenia, hypersensitivity, and vomiting. During the second cycle when all drugs were administered on the
same day, the most common infusion reactions in the pertuzumab-treated group (≥1%) were fatigue, dysgeusia,
hypersensitivity, myalgia, and vomiting.

In APHINITY, when pertuzumab was administered in combination with trastuzumab and chemotherapy on the same day,
infusion-related reactions occurred in 21% of patients, with <1% of patients experiencing Grade 3-4 events.

Observe patients closely for 60 minutes after the first infusion and for 30 minutes after subsequent infusions of
POHERDY. If a significant infusion-related reaction occurs, slow or interrupt the infusion, and administer
appropriate medical therapies. Monitor patients carefully until complete resolution of signs and symptoms. Consider
permanent discontinuation in patients with severe infusion reactions.

Hypersensitivity Reactions/Anaphylaxis

Pertuzumab products can cause hypersensitivity reactions, including anaphylaxis.

In CLEOPATRA, the overall frequency of hypersensitivity/anaphylaxis reactions was 11% in pertuzumab-treated patients,
with Grade 3-4 hypersensitivity reactions and anaphylaxis occurring in 2% of patients.

In NeoSphere, TRYPHAENA, BERENICE, and APHINITY, hypersensitivity/anaphylaxis events were consistent with those
observed in CLEOPATRA. In APHINITY, the overall frequency of hypersensitivity/anaphylaxis was 5% in the
pertuzumab-treated group. The incidence was highest in the pertuzumab plus TCH–treated group (8%), with 1%
Grade 3-4 events.

Observe patients closely for hypersensitivity reactions. Severe hypersensitivity, including anaphylaxis and fatal
events, has been observed in patients treated with pertuzumab products. Angioedema has been described in
postmarketing reports. Medications to treat such reactions, as well as emergency equipment, should be available for
immediate use prior to administration of POHERDY. 

ADVERSE REACTIONS

Metastatic Breast Cancer
The most common adverse reactions (>30%) with
pertuzumab in combination with trastuzumab and docetaxel were diarrhea, alopecia, neutropenia, nausea, fatigue,
rash, and peripheral neuropathy.

Neoadjuvant Treatment of Breast Cancer
The most common adverse reactions (>30%) with
pertuzumab in combination with trastuzumab and docetaxel were alopecia, diarrhea, nausea, and neutropenia.

The most common adverse reactions (>30%) with pertuzumab in combination with trastuzumab and docetaxel when given
for 3 cycles following 3 cycles of FEC were fatigue, alopecia, diarrhea, nausea, vomiting, and neutropenia.

The most common adverse reactions (>30%) with pertuzumab in combination with TCH were fatigue, alopecia, diarrhea,
nausea, vomiting, neutropenia, thrombocytopenia, and anemia.

The most common adverse reactions (>30%) with pertuzumab in combination with trastuzumab and paclitaxel when given
for 4 cycles following 4 cycles of ddAC were nausea, diarrhea, alopecia, fatigue, constipation, peripheral
neuropathy, and headache.

The most common adverse reactions (>30%) with pertuzumab in combination with trastuzumab and docetaxel when given
for 4 cycles following 4 cycles of FEC were diarrhea, nausea, alopecia, asthenia, constipation, fatigue, mucosal
inflammation, vomiting, myalgia, and anemia.

Adjuvant Treatment of Breast Cancer
The most common adverse reactions (>30%) with
pertuzumab in combination with trastuzumab and chemotherapy were diarrhea, nausea, alopecia, fatigue, peripheral
neuropathy, and vomiting.

Before prescribing POHERDY, please read the Prescribing Information, including the Boxed Warning about left ventricular dysfunction and embryo-fetal toxicity.

About Henlius
Shanghai Henlius Biotech, Inc. (2696.HK) is a global, innovation-driven biopharmaceutical company committed to
delivering high-quality, affordable biologic therapies to patients worldwide. Henlius focuses on major disease areas
including oncology, autoimmune diseases, and ophthalmic diseases. Founded in 2010, Henlius has established an
integrated, end-to-end biopharmaceutical platform encompassing global R&D, clinical operations, regulatory
affairs, manufacturing, and commercialisation. Henlius employs nearly 4,000 people globally and operates across
multiple regions, including China, the United States, and Japan. Leveraging the stable cash flow generated from its
biosimilar portfolio to support innovation, Henlius is steadily advancing into its “Globalisation 2.0”
phase, building a scalable and sustainable global growth model. As of early 2026, Henlius has achieved regulatory
approvals for 10 products across over 60 countries and regions worldwide, including seven approvals in China. It has
also reached multiple milestones in major biopharmaceutical markets, with four products approved by the U.S. Food
and Drug Administration (FDA) and five products approved by the European Commission (EC), reflecting its globally
aligned R&D capabilities, quality systems, and manufacturing standards.

Driven by innovation, Henlius has built a diversified, platform-based technology ecosystem through coordinated
R&D efforts across Shanghai, the United States, and other regions. Its innovation platforms span immune
checkpoint inhibitors, immune cell engager technologies (including multispecific T cell engagers), antibody-drug
conjugates (ADCs), and AI-enabled early discovery platforms. Henliuscurrently has more than 50 early-stage
innovative assets, approximately 70% of which are expected to be best-in-class, with over 30 clinical trials ongoing
globally. Henlius’ core product, serplulimab (trade name: Hetronifly^® in Europe), is the
world’s first anti–PD-1 mAb approved for first-line treatment of small cell lung cancer and has been
approved in more than 40 markets worldwide with an accelerated globalisation process. In parallel, multiple
high-potential innovative assets—including the PD-L1 ADC HLX43 and the novel epitope anti-HER2 mAb
HLX22—are advancing through global pivotal clinical development. Supported by a biologics manufacturing
network with a total capacity of 84,000L and GMP certifications from regulatory authorities in China, Europe, and
the United States, Henlius has established a stable global supply system serving six continents. Guided by a
patient-centred mission, Henlius remains focused on addressing unmet medical needs and translating scientific
innovation into meaningful clinical value and patient access, contributing sustainably to the global
biopharmaceutical ecosystem.

To learn more about Henlius, visit https://www.henlius.com/en/index.html and connect with us
on LinkedIn at https://www.linkedin.com/company/henlius/.

About Organon

Organon (NYSE: OGN) is a global healthcare company with a mission to deliver impactful medicines and solutions
for a healthier every day. With a portfolio of over 70 products across Women’s Health and General Medicines,
which includes biosimilars, Organon focuses on addressing health needs that uniquely, disproportionately or
differently affect women, while expanding access to essential treatments in over 140 markets. 

Headquartered in Jersey City, New Jersey, Organon is committed to advancing access, affordability, and innovation in
healthcare. Learn more at www.organon.com and
follow us on LinkedIn, Instagram, X, YouTube, TikTok and Facebook.

Cautionary Note Regarding Forward-Looking Statements

This press release includes “forward-looking statements” within the meaning of the safe harbor provisions
of the US Private Securities Litigation Reform Act of 1995, including, but not limited to, statements about POHERDY
treatment goals and Organon’s ongoing commitment to supporting the sustainability of health care systems while
advancing women’s health through access to quality medicine. Forward-looking statements may be identified by
words such as “will,” “plan,” “ongoing,” “commitment to supporting,”
“may,” and words of similar meaning. These statements are based upon the current beliefs and
expectations of Organon’s management and are subject to significant risks and uncertainties. If underlying
assumptions prove inaccurate, or risks or uncertainties materialize, actual results may differ materially from those
set forth in the forward-looking statements. Factors that could cause results to differ materially from those
described in the forward-looking statements can be found in Organon’s filings with the SEC, including
Organon’s most recent Annual Report on Form 10-K and other SEC filings, available at the SEC’s Internet
site (www.sec.gov).
Organon undertakes no obligation to publicly update any forward-looking statement, whether as a result of new
information, future events or otherwise.

PERJETA is a trademark registered in the European Union by F. Hoffmann-La Roche AG; Organon is not associated with
this trademark owner.

1. PERJETA. Product Information. Genentech, Inc.; 2025.
2. Breast cancer in the EU. European Commission, Joint Research Centre. October 2023. Accessed April 14, 2026. https://ecis.jrc.ec.europa.eu/sites/default/files/2024-01/jrc_Breast_cancer_2022_Oct_2023.pdf
3. European Medicines Agency and the European Commission. Biosimilars in the EU: information guide for healthcare professionals. European Medicines Agency (EMA). Last Updated October 29, 2019. Accessed April 14, 2026. https://www.ema.europa.eu/en/documents/leaflet/biosimilars-eu-information-guide-healthcare-professionals_en.pdf
4. Troein P, Newton M, Stoddart K, Travaglio M, Arias A. The impact of biosimilar competition in Europe. IQVIA; January 2025. Accessed April 14, 2026. https://www.iqvia.com/-/media/iqvia/pdfs/library/white-papers/the-impact-of-biosimilar-competition-in-europe-2024.pdf
5. Biosimilar medicines: overview. European Medicines Agency (EMA). April 2, 2025. Accessed April 14, 2026. https://www.ema.europa.eu/en/human-regulatory-overview/biosimilar-medicines-overview
6. Organon Enters into Global License Agreement to Commercialize Henlius’ Investigational Perjeta ®(Pertuzumab) and Prolia ®/Xgeva ®(Denosumab) Biosimilar Candidates. Organon. June 13, 2022. Accessed April 14, 2026. https://www.organon.com/news/organon-enters-into-global-license-agreement-to-commercialize-henlius-investigational-perjeta-pertuzumab-and-prolia-xgeva-denosumab-biosimilar-candidates/

Organon Media Contacts:
Karissa Peer
(614) 314-8094
Felicia Bisaro
(646) 703-1807

Organon Investor Contacts:
Jennifer Halchak
(201) 275-2711
Renee McKnight
(551) 204-6129

Henlius Media Contacts:
Janice Han
jiayi_han@henlius.com
Bella Zhou
wenting_zhou@henlius.com

Henlius Investor Contact:
Venus Hu
junyan_Hu@henlius.com

Source: Organon & Co.