US Patient Site

Recommended dosing and administration for PHESGO

Step-by-step tutorial for preparing and administering PHESGO

Dosing schedules

Neoadjuvant

Adjuvant

Metastatic breast cancer (MBC)

Administration instructions

Important: PHESGO has different dosage and administration instructions than IV pertuzumab, IV trastuzumab, and subcutaneous trastuzumab when administered alone. Do not substitute PHESGO for or with PERJETA® (pertuzumab), trastuzumab, ado-trastuzumab emtansine, or fam-trastuzumab deruxtecan.1

PHESGO should be administered every 3 weeks1

Loading (initial) dose

1200 mg pertuzumab, 600 mg trastuzumab, 30,000 units hyaluronidase per 15 mL supplied in a single-dose, ready-to-use vial

Administer subcutaneously over approximately 8 minutes at a rate of no more than 2 mL/min

Observe for hypersensitivity or administration-related reactions:
minimum of 30 minutes*

NDC: 50242-245-01

Maintenance dose

600 mg pertuzumab, 600 mg trastuzumab, 20,000 units hyaluronidase per 10 mL supplied in a single-dose, ready-to-use vial

Administer subcutaneously over approximately 5 minutes at a rate of no more than 2 mL/min

Observe for hypersensitivity or administration-related reactions:
minimum of 15 minutes*

NDC: 50242-260-01

*Medications to treat such reactions, as well as emergency equipment, should be available for immediate use.

PHESGO must always be administered by a healthcare professional.

PHESGO is for subcutaneous use ONLY in the thigh. Do NOT administer intravenously.

  • Do not split the dose between 2 syringes or between 2 sites of administration
  • Injection site should be alternated between the left and right thigh only
  • New injections should be given at least 1 inch from the previous site on healthy skin and never into areas where the skin is red, bruised, tender, or hard
  • During the treatment course with PHESGO, other subcutaneous medications should preferably be injected at different sites

Patients currently receiving IV PERJETA + trastuzumab can be transitioned to PHESGO if eligible.1

Additional dosing considerations and dose modifications

Assessment of HER2 protein overexpression and/or HER2 gene amplification should be performed using FDA-approved tests specific for breast cancers by laboratories with demonstrated proficiency.

  • In patients receiving an anthracycline-based regimen for EBC, administer PHESGO following completion of the anthracycline
  • In patients receiving PHESGO for EBC with docetaxel or paclitaxel, administer docetaxel or paclitaxel after PHESGO
  • In patients receiving PHESGO for MBC with docetaxel, administer docetaxel after PHESGO

<6 weeks since last dose of IV PERJETA + trastuzumab
START PHESGO with maintenance dose

≥6 weeks since last dose of IV PERJETA + trastuzumab
START PHESGO with loading dose

  • In patients receiving IV PERJETA + trastuzumab with <6 weeks since their last dose, administer PHESGO as a maintenance dose of 600 mg, 600 mg, 20,000 units/10 mL and every 3 weeks for subsequent administrations
  • In patients receiving IV PERJETA + trastuzumab with ≥6 weeks since their last dose, administer PHESGO as an initial dose of 1,200 mg, 600 mg, 30,000 units/15 mL, followed by a maintenance dose of 600 mg, 600 mg, 20,000 units/10 mL every 3 weeks for subsequent administrations
  • In the PHranceSCa trial, patients were monitored for 30 minutes after their first dose of PHESGO, regardless of whether a loading dose was required. Medications to treat such reactions, as well as emergency equipment, should be available for immediate use
  • If the time between 2 sequential injections is less than 6 weeks, do not wait until the next planned dose. The maintenance dose of 600 mg pertuzumab/600 mg trastuzumab/20,000 units hyaluronidase should be administered
  • If the time between 2 sequential injections is 6 weeks or more, the initial dose of 1200 mg pertuzumab/600 mg trastuzumab/30,000 units hyaluronidase should be re-administered, followed every 3 weeks thereafter by a dose of 600 mg pertuzumab/600 mg trastuzumab/20,000 units hyaluronidase
  • No dose adjustments for PHESGO are required for patient body weight or for concomitant chemotherapy regimen
  • For chemotherapy dose modification, see relevant prescribing information
  • If patient experiences a significant injection-related reaction, slow down or pause the injection and administer appropriate medical therapies. Evaluate and carefully monitor patients until complete resolution of signs and symptoms
  • If patient experiences a serious hypersensitivity reaction (e.g., anaphylaxis), discontinue injection immediately

Assess left ventricular ejection fraction (LVEF) prior to initiation of PHESGO and at regular intervals during treatment.

  Pre-treatment LVEF: Withhold PHESGO for at least 3 weeks for an LVEF decrease to: Resume PHESGO after 3 weeks if LVEF has recovered to:
Early Breast Cancer (EBC) ≥55%† <50% with a fall of ≥10%-points below pre-treatment value EITHER ≥50% OR <10%-points below pre-treatment value
Metastatic Breast Cancer (MBC) ≥50% EITHER <40% OR 40%-45% with a fall of ≥10%-points below pre-treatment value EITHER >45% OR 40%-45% with a fall of <10%-points below pre-treatment value

†For patients receiving anthracycline-based chemotherapy, a LVEF of ≥50% is required after completion of anthracyclines, before starting PHESGO.

Monitor LVEF prior to initiation and then every ~12 weeks in MBC and EBC (once during neoadjuvant therapy).

If after a repeat assessment within approximately 3 weeks, the LVEF has not improved, has declined further, and/or the patient is symptomatic, permanently discontinue PHESGO.

NEXT: EXPLORE PREPARATION AND STORAGE
Illustration of syringe and stopwatch

PHESGO could save time for your patients and practice1

SEE THE DATA
Image of a shield with plus sign icon in the middle

Most major insurance plans provide coverage for PHESGO*2

*Data current as of June 2025. Insurer policies may vary and are subject to change.

LEARN MORE

Learn More About Dosing & Administration

Information about how to properly store, prepare, and administer PHESGO, including useful graphics and helpful tips.

Download
Illustration of syringe with stars

See which treatment patients preferred*

*Based on the PHranceSCa trial.1

SEE THE DATA

    • PHESGO Prescribing Information. Genentech, Inc. 2026.

      PHESGO Prescribing Information. Genentech, Inc. 2026.

    • Data on file. Genentech, Inc.

      Data on file. Genentech, Inc.

    Important Safety Information & Indications

    Indications

    Early Breast Cancer

    PHESGO® (pertuzumab, trastuzumab, and hyaluronidase-zzxf) is indicated for use in combination with chemotherapy for

    • the neoadjuvant treatment of adult patients 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 (EBC)
    • the adjuvant treatment of adult patients with HER2-positive early breast cancer (EBC) at high risk of recurrence

    Select patients for therapy based on an FDA-authorized companion diagnostic test.

    Metastatic Breast Cancer

    PHESGO is indicated for use in combination with docetaxel for the treatment of adult patients with HER2-positive metastatic breast cancer (MBC) who have not received prior anti-HER2 therapy or chemotherapy for metastatic disease.

    Select patients for therapy based on an FDA-authorized companion diagnostic test.

    BOXED WARNINGS: Cardiomyopathy, Embryo-Fetal Toxicity, and Pulmonary Toxicity

    • PHESGO administration can result in subclinical and clinical cardiac failure. The incidence and severity were highest in patients receiving PHESGO with anthracycline-containing chemotherapy regimens. Evaluate cardiac function prior to and during treatment with PHESGO. Discontinue PHESGO treatment in patients receiving adjuvant therapy and withhold PHESGO in patients with metastatic disease for clinically significant decrease in left ventricular function

    • Exposure to PHESGO can result in embryo-fetal death and birth defects, including oligohydramnios and oligohydramnios sequence manifesting as pulmonary hypoplasia, skeletal abnormalities, and neonatal death. Advise patients of these risks and the need for effective contraception

    • PHESGO administration can result in serious and fatal pulmonary toxicity. Discontinue PHESGO for anaphylaxis, angioedema, interstitial pneumonitis, or acute respiratory distress syndrome. Monitor patients until symptoms completely resolve

    Contraindications

    PHESGO is contraindicated in patients with known hypersensitivity to pertuzumab, or trastuzumab, or hyaluronidase, or to any of its excipients.

    Additional Important Safety Information

    Cardiomyopathy

    • PHESGO administration can result in subclinical and clinical cardiac failure. The incidence and severity were highest in patients receiving PHESGO with anthracycline-containing chemotherapy regimens. An increased incidence of left ventricular ejection fraction (LVEF) decline has been observed in patients treated with intravenous pertuzumab, intravenous trastuzumab, and docetaxel

    • PHESGO can cause left ventricular cardiac dysfunction, arrhythmias, hypertension, disabling cardiac failure, cardiomyopathy, and cardiac death

    • PHESGO can also cause asymptomatic decline in LVEF

    • Patients who receive anthracycline after stopping PHESGO may also be at increased risk of cardiac dysfunction

    • Discontinue PHESGO treatment in patients receiving adjuvant therapy and withhold PHESGO in patients with metastatic disease for clinically significant decrease in left ventricular function

    Cardiac Monitoring

    • Evaluate cardiac function prior to and during treatment. For adjuvant breast cancer therapy, also evaluate cardiac function after completion of PHESGO

    • Conduct thorough cardiac assessment, including history, physical examination, and determination of LVEF by echocardiogram or MUGA scan

    • Monitor frequently for decreased left ventricular function during and after PHESGO treatment

    • Monitor more frequently if PHESGO is withheld for significant left ventricular cardiac dysfunction

    Embryo-Fetal Toxicity

    • PHESGO can cause fetal harm when administered to a pregnant woman. In post-marketing reports, use of intravenous trastuzumab during pregnancy resulted in cases of oligohydramnios and oligohydramnios sequence manifesting as pulmonary hypoplasia, skeletal abnormalities, and neonatal death. In an animal reproduction study, administration of intravenous pertuzumab to pregnant cynomolgus monkeys during the period of organogenesis resulted in oligohydramnios, delayed fetal kidney development, and embryo-fetal death at exposures 2.5 to 20 times the exposure in humans at the recommended dose, based on Cmax

    • Verify the pregnancy status of females of reproductive potential prior to the initiation of PHESGO. Advise pregnant women and females of reproductive potential that exposure to PHESGO during pregnancy or within 7 months prior to conception can result in fetal harm. Advise females of reproductive potential to use effective contraception during treatment and for 7 months following the last dose of PHESGO

    • If PHESGO is administered during pregnancy, or if a patient becomes pregnant while receiving PHESGO or within 7 months following the last dose of PHESGO, health care providers and patients should immediately report PHESGO exposure to Genentech at 1-888-835-2555

    Pulmonary Toxicity

    • PHESGO can cause serious and fatal pulmonary toxicity. These adverse reactions have been reported with intravenous trastuzumab

    • Pulmonary toxicity includes dyspnea, interstitial pneumonitis, pulmonary infiltrates, pleural effusions, non-cardiogenic pulmonary edema, pulmonary insufficiency and hypoxia, acute respiratory distress syndrome, and pulmonary fibrosis. Patients with symptomatic intrinsic lung disease or with extensive tumor involvement of the lungs, resulting in dyspnea at rest, appear to have more severe toxicity

    Exacerbation of Chemotherapy-Induced Neutropenia

    • PHESGO may exacerbate chemotherapy-induced neutropenia. In randomized controlled clinical trials with intravenous trastuzumab, Grade 3-4 neutropenia and febrile neutropenia were higher in patients receiving trastuzumab in combination with myelosuppressive chemotherapy as compared to those who received chemotherapy alone. The incidence of septic death was similar among patients who received trastuzumab and those who did not

    Hypersensitivity and Administration-Related Reactions

    • Severe administration-related reactions (ARRs), including hypersensitivity, anaphylaxis, and events with fatal outcomes, have been associated with intravenous pertuzumab and trastuzumab. Patients experiencing dyspnea at rest due to complications of advanced malignancy and comorbidities may be at increased risk of a severe or of a fatal ARR

    • In the FeDeriCa trial the incidence of hypersensitivity was 1.2% in the PHESGO arm. ARRs occurred in 21% of patients who received PHESGO. In the PHESGO arm, the most common ARRs were injection site reaction (15%) and injection site pain (2%)

    • Closely monitor patients during and for 30 minutes after the injection of initial dose and during and for 15 minutes following subsequent injections of maintenance dose of PHESGO. If a significant injection-related reaction occurs, slow down or pause the injection and administer appropriate medical therapies. Evaluate and carefully monitor patients until complete resolution of signs and symptoms

    • Permanently discontinue treatment with PHESGO in patients who experience anaphylaxis or severe injection-related reactions. Medications to treat such reactions, as well as emergency equipment, should be available for immediate use. For patients experiencing reversible Grade 1 or 2 hypersensitivity reactions, consider pre-medication with an analgesic, antipyretic, or an antihistamine prior to readministration of PHESGO

    Most Common Adverse Reactions

    Early Breast Cancer

    The most common adverse reactions (>30%) with PHESGO were alopecia, nausea, diarrhea, anemia, and asthenia.

    Metastatic Breast Cancer (based on IV pertuzumab)

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

    You are encouraged to report side effects to Genentech and the FDA. You may report side effects to the FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. You may also report side effects to Genentech at 1-888-835-2555.

    Please see full Prescribing Information for additional Important Safety Information, including BOXED WARNINGS.

    +