Genentech to Present New Data at ASCO 2026, Reinforcing Giredestrant’s Potential to Transform the Treatment Paradigm in Early Breast Cancer

• New giredestrant data from the lidERA study on its potential as a new standard of care for adjuvant ER-positive breast cancer across all menopausal stages
• Primary results from the persevERA study on the numerical improvement in progression-free survival observed with first-line giredestrant plus palbociclib in advanced, endocrine-sensitive disease
• Overall, nine approved and investigational medicines, including bispecific antibodies, antibody-drug conjugates and brain-permeable molecules, with ASCO data targeting urgent needs in breast, blood, lung and other cancers

SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)--Genentech, a member of the Roche Group (SIX: RO, ROP; OTCQX: RHHBY), will present new data from nine approved and investigational medicines across more than 15 indications at the 2026 American Society of Clinical Oncology (ASCO) Annual Meeting, held May 29 to June 2 in Chicago.

"Genentech’s ASCO data reflect our commitment to addressing those cancers that impose the highest burden on patients and society," said Levi Garraway, M.D., Ph.D., chief medical officer and head of Global Product Development. "In particular, our ASCO data highlight significant advances in breast cancer, including the latest results for giredestrant and our evolving approach to HER2-positive metastatic disease."

Redefining the standard of care in breast cancer

Genentech's ASCO 2026 focus is on giredestrant, an investigational, oral, selective estrogen receptor degrader (SERD) being studied in early and advanced estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer.

This subtype accounts for approximately 70% of breast cancer cases, and the majority are diagnosed in the early stage. Data from three Phase III trials demonstrate giredestrant's potential as a future standard of care endocrine therapy across multiple disease stages:

• lidERA Breast Cancer: Building on the transformational results shared in December 2025, which demonstrated a 30% reduction in the risk of invasive disease recurrence or death, new data will indicate whether the efficacy and safety of giredestrant remain consistent across pre- and post-menopausal patients with early breast cancer. The lidERA data have been submitted to the U.S. Food and Drug Administration (FDA).
• persevERA Breast Cancer: Primary results investigating giredestrant in combination with palbociclib as a first-line therapy in locally advanced or metastatic cancer will be presented. These data will provide context following the announcement that while the study did not meet its primary endpoint, the giredestrant combination showed a numerical improvement in this distinct patient population, suggesting that giredestrant is active in the first-line setting.
• evERA Breast Cancer: New post-progression treatment analyses will be shared exploring the sustained clinical benefit for people treated with giredestrant plus everolimus in the post-cyclin-dependent kinase 4/6 inhibitor setting. The U.S. FDA recently accepted the New Drug Application for giredestrant based on the positive evERA data.

Our ASCO data also highlight progress in HER2-positive breast cancer, an area Genentech has led for over 30 years:

• RG6596/ZN-A-1041 in HER2-positive breast cancer: Preliminary results from a Phase Ic expansion trial will provide early information on the safety and efficacy of ZN-A-1041, a highly blood-brain barrier-permeable, HER2-selective tyrosine kinase inhibitor, in combination with other HER2-targeted therapies, for patients with pre-treated HER2-positive metastatic breast cancer. Designed for enhanced brain penetration, ZN-A-1041 may improve the ability to prevent and treat brain metastases, a major challenge in metastatic breast cancers.

Advancing precision medicine and novel combinations

Genentech is also presenting data from its diverse pipeline targeting specific genetic drivers and difficult-to-treat cancers, including:

• Divarasib in non-small cell lung cancer (NSCLC): Genentech will present results from the Krascendo 170 Phase Ib/II study evaluating the next-generation oral KRAS G12C inhibitor divarasib combined with pembrolizumab in treatment-naive patients with KRAS G12C+ advanced NSCLC. These data informed the Phase III Krascendo 2 study, which investigates this combination as a first-line therapy regardless of PD-L1 status. Divarasib is currently being evaluated in three pivotal Phase III studies as a monotherapy or in chemotherapy-free combinations.
• Lunsumio^® (mosunetuzumab) plus Polivy^® (polatuzumab vedotin) in diffuse large B-cell lymphoma (DLBCL): Genentech will present updated data from the Phase III SUNMO trial to further establish the efficacy and safety of Lunsumio plus Polivy compared to chemotherapy (R-GemOx) particularly in second-line patients with relapsed/refractory DLBCL who are not eligible for transplant. This first combination of a bispecific antibody and antibody-drug conjugate could potentially provide patients who often face poor prognoses and significant treatment burdens with an effective, fixed-duration, chemotherapy-free regimen.

Overview of key presentations featuring Genentech medicines and molecules:

Lunsumio and Lunsumio VELO U.S. Indication

Lunsumio (mosunetuzumab-axgb) or Lunsumio VELO is a prescription medicine used to treat adults with follicular lymphoma whose cancer has come back or did not respond to previous treatment, and who have already received two or more treatments.

It is not known if Lunsumio or Lunsumio VELO is safe and effective in children. The conditional approval for this use is based on response rate. There are ongoing studies to establish how well the drug works.

Important Safety Information

What is the most important information I should know about Lunsumio or Lunsumio VELO?

Lunsumio or Lunsumio VELO can cause Cytokine Release Syndrome (CRS), a serious side effect that is common during treatment with Lunsumio or Lunsumio VELO, and can also be severe or life-threatening.

Get medical help right away if you develop any signs or symptoms of CRS at any time, including:

• fever of 100.4°F (38°C) or higher
• chills
• low blood pressure
• fast or irregular heartbeat
• tiredness or weakness
• difficulty breathing
• headache
• confusion
• feeling anxious
• dizziness or light-headedness
• nausea
• vomiting

Due to the risk of CRS, you will receive Lunsumio or Lunsumio VELO on a “step-up dosing schedule.”

• The step-up dosing schedule is when you receive smaller “step-up” doses before receiving higher doses of Lunsumio or Lunsumio VELO during your first cycle of treatment
• If your dose of Lunsumio or Lunsumio VELO is delayed for any reason, you may need to repeat the “step-up dosing schedule”
• You may receive medicines to help reduce your risk of CRS before your dose

Your healthcare provider will check you for CRS during treatment with Lunsumio or Lunsumio VELO and may treat you in a hospital if you develop signs and symptoms of CRS. Your healthcare provider may temporarily stop or completely stop your treatment with Lunsumio or Lunsumio VELO, if you have severe side effects.

What are the possible side effects of Lunsumio or Lunsumio VELO?

Lunsumio or Lunsumio VELO can cause serious side effects, including:

• Neurologic problems. Lunsumio or Lunsumio VELO can cause serious and life-threatening neurologic problems. Your healthcare provider will check you for neurologic problems during treatment with Lunsumio or Lunsumio VELO. Your healthcare provider may also refer you to a healthcare provider who specializes in neurologic problems. Tell your healthcare provider right away if you develop any signs or symptoms of neurologic problems during or after treatment with Lunsumio or Lunsumio VELO, including:
  • headache
  • numbness and tingling of the arms, legs, hands, or feet
  • dizziness
  • confusion and disorientation
  • difficulty paying attention or understanding things
  • forgetting things or forgetting who or where you are
  • trouble speaking, reading or writing
  • sleepiness or trouble sleeping
  • tremors
  • loss of consciousness
  • seizures
  • muscle problems or muscle weakness
  • loss of balance or trouble walking
  • tiredness
• Serious infections. Lunsumio or Lunsumio VELO can cause serious infections that may lead to death. Your healthcare provider will check you for signs and symptoms of infection before and during treatment. Tell your healthcare provider right away if you develop any signs or symptoms of infection during treatment with Lunsumio or Lunsumio VELO, including:
  • fever of 100.4°F (38°C) or higher
  • cough
  • chest pain
  • tiredness
  • shortness of breath
  • painful rash
  • sore throat
  • pain during urination
  • feeling weak or generally unwell
• Hemophagocytic lymphohistiocytosis (HLH). Lunsumio or Lunsumio VELO can cause overactivity of the immune system, a condition called hemophagocytic lymphohistiocytosis. HLH can be life-threatening and has led to death in people treated with Lunsumio or Lunsumio VELO. Your healthcare provider will check you for HLH especially if your CRS lasts longer than expected. Signs and symptoms of HLH include:
  • fever
  • enlarged spleen
  • easy bruising
  • low blood cell counts
  • liver problems
• Low blood cell counts. Low blood cell counts are common during treatment with Lunsumio or Lunsumio VELO and can also be serious or severe. Your healthcare provider will check your blood cell counts during treatment with Lunsumio or Lunsumio VELO. Lunsumio or Lunsumio VELO can cause the following low blood cell counts:
  • low white blood cell counts (lymphopenia [for Lunsumio VELO only] and neutropenia). Low white blood cells can increase your risk for infection
  • low red blood cell counts (anemia). Low red blood cells can cause tiredness and shortness of breath
  • low platelet counts (thrombocytopenia). Low platelet counts can cause bruising or bleeding problems
• Growth in your tumor or worsening of tumor-related problems (tumor flare). Lunsumio or Lunsumio VELO can cause serious or severe worsening of your tumor. Tell your healthcare provider if you develop any of these signs or symptoms of tumor flare during your treatment with Lunsumio or Lunsumio VELO:
  • chest pain
  • cough
  • trouble breathing
  • tender or swollen lymph nodes
  • pain or swelling at the site of the tumor

Your healthcare provider may temporarily stop or permanently stop treatment with Lunsumio or Lunsumio VELO if you develop severe side effects.

The most common side effects of Lunsumio include: CRS, tiredness, rash, headache, fever, muscle pain, cough, itching, and numbness, tingling, or pain in the hands or feet (nerve damage).

The most common side effects of Lunsumio VELO include: injection site reactions, tiredness, rash, CRS, COVID-19, muscle and joint pain, and diarrhea.

The most common severe abnormal blood test results with Lunsumio include: decreased phosphate, increased glucose, and increased uric acid levels.

The most common severe abnormal blood test results with Lunsumio VELO include: decreased white blood cell counts and increased uric acid levels.

Before receiving Lunsumio or Lunsumio VELO, tell your healthcare provider about all of your medical conditions, including if you:

• have ever had an infusion reaction after receiving Lunsumio
• have an infection or have had an infection in the past which lasted a long time or keeps coming back
• have or have had Epstein-Barr Virus
• are pregnant or plan to become pregnant. Lunsumio or Lunsumio VELO may harm your unborn baby. Tell your healthcare provider right away if you become pregnant or think you may be pregnant during treatment with Lunsumio or Lunsumio VELO

Females who are able to become pregnant:

• your healthcare provider should do a pregnancy test before you start treatment with Lunsumio or Lunsumio VELO
• use an effective method of birth control (contraception) during your treatment and for 3 months after the last dose of Lunsumio or Lunsumio VELO
• are breastfeeding or plan to breastfeed. It is not known if Lunsumio or Lunsumio VELO passes into your breast milk. Do not breastfeed during treatment and for 3 months after the last dose of Lunsumio or Lunsumio VELO

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

What should I avoid while receiving Lunsumio or Lunsumio VELO?

Do not drive, operate heavy machinery, or do other dangerous activities if you develop dizziness, confusion, tremors, sleepiness, or any other symptoms that impair consciousness until your signs and symptoms go away. These may be signs and symptoms of CRS or neurologic problems.

These are not all of the possible side effects of Lunsumio or Lunsumio VELO. Talk to your healthcare provider for more information about the benefits and risks of Lunsumio or Lunsumio VELO.

You may report side effects to the FDA at (800) FDA-1088 or https://www.fda.gov/safety/medwatch-fda-safety-information-and-adverse-event-reporting-program. You may also report side effects to Genentech at (888) 835-2555.

Please see Important Safety Information, including Serious Side Effects, as well as the Lunsumio full Prescribing Information and Medication Guide and Lunsumio VELO full Prescribing Information and Medication Guide and on https://www.Lunsumio.com.

Polivy U.S. Indication

Polivy is a prescription medicine used with other medicines (a rituximab product, cyclophosphamide, doxorubicin, and prednisone) as a first treatment for adults who have moderate to high risk diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) or high-grade B-cell lymphoma (HGBL).

Polivy is a prescription medicine used with other medicines, bendamustine and a rituximab product, to treat DLBCL in adults who have progressed after at least 2 prior therapies.

Important Safety Information

Possible serious side effects

Everyone reacts differently to Polivy therapy, so it’s important to know what the side effects are. Some people who have been treated with Polivy have experienced serious to fatal side effects. Your doctor may stop or adjust your treatment if any serious side effects occur. Be sure to contact your healthcare team if there are any signs of these side effects.

• Nerve problems in your arms and legs: This may happen as early as after your first dose and may worsen with every dose. Your doctor will monitor for signs and symptoms, such as changes in your sense of touch, numbness or tingling in your hands or feet, nerve pain, burning sensation, any muscle weakness, or changes to your walking pattern
• Infusion-related reactions: You may experience fever, chills, rash, breathing problems, low blood pressure, or hives within 24 hours of your infusion
• Low blood cell counts: Treatment with Polivy can cause severe low blood cell counts. Your doctor will monitor your blood counts throughout treatment with Polivy
• Infections: If you have a fever of 100.4°F (38°C) or higher, chills, cough, or pain during urination, contact your healthcare team. Your doctor may also give you medication before giving you Polivy, which may prevent some infections
• Rare and serious brain infections: Your doctor will monitor closely for signs and symptoms of these types of infections. Contact your doctor if you experience confusion, dizziness or loss of balance, trouble talking or walking, or vision changes
• Tumor lysis syndrome: Caused by the fast breakdown of cancer cells. Signs include nausea, vomiting, diarrhea, and lack of energy
• Potential harm to liver: Some signs include tiredness, weight loss, pain in the abdomen, dark urine, and yellowing of your skin or the white part of your eyes. You may be at higher risk if you already had liver problems or you are taking other medication

Side effects seen most often

The most common side effects during treatment were

• Nerve problems in arms and legs
• Nausea
• Tiredness or lack of energy
• Diarrhea
• Constipation
• Hair loss
• Redness and sores of the lining of the mouth, lips, throat, and digestive tract

Polivy may lower your red or white blood cell counts and increase uric acid levels.

Polivy may not be for everyone. Talk to your doctor if you are

• Pregnant or think you are pregnant: Data have shown that Polivy may harm your unborn baby
• Planning to become pregnant: Women should avoid getting pregnant while taking Polivy. Women should use effective contraception during treatment and for 3 months after their last Polivy treatment. Men taking Polivy should use effective contraception during treatment and for 5 months after their last Polivy treatment
• Breastfeeding: Women should not breastfeed while taking Polivy and for 2 months after the last dose

These may not be all the side effects. Talk to your healthcare provider for more information about the benefits and risks of Polivy treatment.

You may report side effects to the FDA at (800) FDA-1088 or http://www.fda.gov/medwatch. You may also report side effects to Genentech at (888) 835-2555.

Please see the full Prescribing Information and visit https://www.Polivy.com for additional Important Safety Information.

What is Itovebi?

Itovebi^® (inavolisib) is a prescription medicine used in combination with the medicines palbociclib and fulvestrant to treat adults who have hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer that has an abnormal phosphatidylinositol-3-kinase catalytic subunit alpha (PIK3CA) gene, and has spread to nearby tissue or lymph nodes (locally advanced), or to other parts of the body (metastatic), and has come back after hormone (endocrine) therapy.

Your healthcare provider wil

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