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Trial Risks

Possible known and unknown side effects

This is the first time ESR1 peptide vaccine has been given to humans. While on this study, you are at risk for side effects below and possibly others. There may be other side effects not listed that the researchers cannot predict. You should discuss these with your doctor.  

The ESR1 Peptide Vaccine consists of ESR1 peptides, GM-CSF, and Montanide. The possible side effects for each are described.

ESR1/Montanide/GM-CSF Peptide Risks 

Possible minor side effects

    Injection site reaction

    stomach pain
    loss of appetite
    tired feeling
    hair loss
    weight loss
    skin rash or itching, or
    injection site reactions (redness, swelling, itching, lumps, irritation, or bruising)


Possible Major side effect

    chest pain
    sudden weight gain
    swelling of the hands or feet
    shortness of breath
    black stools
    persistent stomach or abdominal pain,
    fast or irregular heartbeat
    vision problems
    a sudden reddening of the face/neck/chest
    severe dizziness

    Allergic reactions with swelling in such places as your throat or lungs.  This could lead to shortness of breath, breathing failure or death.

Medications that might be needed to treat allergic reactions include antihistamines such as diphenhydramine (Benadryl), epinephrine and corticosteroids. Other medications may be given to make side effects less serious and uncomfortable. 

Additional Study Drug Risks:
Your immune system could be stimulated to attack your own body (called autoimmunity), causing a low white blood cell count, which could lead to developing an infection, skin rash, joint swelling, intestinal inflammation (chronic colitis), or fluid around the heart and lungs.  
Because this is the first time ESR1 peptide vaccine has been given to humans, there may be risks, discomforts, drug interactions or side effects that are not yet known.  
Some side effects may occur that do not need medical attention and may go away as your body adjusts.  Others may be severe and need immediate attention or lead to hospitalization.  Seek emergency care and contact your doctor immediately if severe side effects occur.
Administration of ESR1 peptide vaccine with any other breast cancer therapies is investigational and the possible risks and side effects of combining the study drug with these therapies are unknown.  
Your doctor will discuss with you the risks of the specific breast cancer therapy you receive. You should inform your doctor immediately of any side effects you experience.  

Get emergency medical help if you have any serious side effects or any of these signs of an allergic reaction: hives, difficulty breathing, and swelling of your face, lips, tongue, or throat.
We will tell you about new information that may affect your health, welfare, or willingness to stay in this study, including any new information about the investigational vaccine, the harms and benefits experienced by other individuals involved in the study, and any long-term effects that may be observed.
Reproductive Risks:
For Women:
The effects of ESR1 peptide vaccine on a developing pregnancy or breastfeeding infant are unknown.  To reduce the risk of any harmful effects, women who are pregnant, planning a pregnancy, or breastfeeding are not allowed to participate in studies using the ESR1 peptide vaccine. 
If you are a woman who could possibly become pregnant (you have not completed menopause, had a hysterectomy and/or both tubes and/or both ovaries removed) and you have a partner who is able to father children, a blood pregnancy test will be performed and it must be negative before you can continue in this study. In women 40 years old and older, blood pregnancy tests can sometimes give a false positive or indeterminate result, and additional testing may be required to confirm your eligibility. 
You and your partner must agree to either abstain completely from vaginal intercourse for the duration of the study until at least 4 months after the last dose of study drug, or use highly effective methods of contraception for the same length of time. These methods include (a) partner vasectomy, (b) bilateral tubal ligation, or (c) intrauterine devices (IUDs).   Hormonal methods, such as birth control pills or implants, may not be safe in women with ER positive breast cancer.  Your study doctor will discuss contraceptive options with you, given your medical condition, your personal preferences, and the level of effectiveness required by this study. Because no method of birth control is 100% effective, you should notify your study doctor immediately if you think there is any chance you could be pregnant.  

If you do become pregnant during the study, your study doctor will stop the study drug, withdraw you from the study, and notify the sponsor.  You will be followed for the duration of the pregnancy to better understand the potential effects of the study drug on pregnancy outcomes. 

For Men:
It is unknown whether pregnancies that began while the father was taking ESR1 peptide vaccine are at increased risk for birth defects, miscarriages, or other bad outcomes. In addition, ESR1 peptide vaccine may be present in semen and transmitted to a partner during sexual activity.  To reduce the risk of any harmful effects, men who are trying to become fathers are not allowed to participate in this study. 
The study drug may be transmitted to a partner during sex, which could possibly have bad effects for your partner.   Therefore, you must agree to use a condom every time you have any type of intercourse, even if you have had a vasectomy (because vasectomy does not prevent transmission of drug in semen), your partner is a woman who cannot possibly become pregnant, or your partner is a man.  

You should not donate sperm for the duration of the study and for 4 months after your last dose of study drug.
You should notify your partner about your participation in this study and the potential risks to pregnancies that began while you are taking the study drug.  If your partner is not currently using another form of birth control, she should discuss options with her doctor. If she does become pregnant during the study, you should notify your study doctor and she should notify her doctor. She will be asked for permission to collect information about the pregnancy to better understand the potential effects of the study drug on pregnancy outcomes.
For All Study Participants:
You should not donate blood while you are in this study and for possibly longer. Please discuss with your study doctor how long you should wait before donating any blood.
Drug and Food Interactions: For your safety, you must tell the study doctor or nurse about all the prescribed medical foods and drugs, herbal products, over-the-counter (OTC) drugs, vitamins, natural remedies and alcohol that you are taking before you start the study and before taking any of these products while you are on the study.
Risks of Blood Draws: Risks associated with drawing blood from your arm include momentary discomfort and/or bruising. Infection, excess bleeding, clotting, or fainting are also possible, although unlikely.

Risks of Intradermal and Subcutaneous Injections: The ESR1 vaccine will be administered by a combination of intradermal (ID) and subcutaneous (SQ) injection. Risks associated with this include momentary discomfort and/or bruising. Infection, excess bleeding, clotting, or fainting are also possible, although unlikely.
Risks of Biopsies (Skin):
Skin biopsy is generally a non-hazardous procedure; however, possible hazards may include: 1) reaction to anesthetic (numbing medicine), 2) excessive bleeding, 3) bruising, 4) infection and 5) excessive scarring. While the local numbing medicine xylocaine is almost entirely free from allergic properties 
(such as causing hives), an allergic reaction is possible, and you will not be given xylocaine if you have a history of such a reaction. The xylocaine will be given by a small injection into the skin at the site of the skin biopsy. To speed healing, one or two stitches (also known as sutures) will be placed, which will be removed 5 - 7 days later. During the healing process, you will be asked to keep the biopsy site clean and dry, and to apply antibiotic ointment. Infection rarely occurs and is largely prevented by the use of an aseptic (or sterile) biopsy technique and proper wound care. If infection does occur, you will be instructed to keep the wound clean and to apply warm, wet compresses for 15 minutes, three times a day, until the infection subsides. If the infection persists, antibiotics may be prescribed.

Only 10-15 minutes will be required for the biopsy procedure. After the anesthesia wears off, there will be some soreness at the biopsy site that will last for a few hours. A small scar will develop at the site of the biopsy.
There may be risks, discomforts, drug interactions or side effects that are not yet known.

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