Vaccination of High Risk Breast Cancer Patients

The purpose of this study is to evaluate an investigational agent, P10s-PADRE, a peptide mimotope-based vaccine, in combination with standard neoadjuvant chemotherapy in patients with clinical stage I, II or III estrogen-receptor (ER)-positive, HER2-negative breast cancer.

This is a single-arm, multi-site Phase I/II study designed with the two goals being (1) to evaluate the feasibility of combining vaccination with the P10s-PADRE formulation with neoadjuvant chemotherapy and (2) to determine if the polymerase chain reaction (pCR) rate among ER-positive, HER2-negativebreast-cancer patients treated with the combination is significantly higher than the 8% rate observed among ER-positive breast-cancer subjects in a pooled analysis of seven randomized clinical trials. P10s-PADRE vaccine with MONTANIDE™ ISA 51 VG as adjuvant will be given in combination with neoadjuvant chemotherapy in female patients with clinical stage I, II or III ER-positive, HER2-negative breast cancer.

This combined Phase I/II feasibility-and-efficacy study will have three parts. Its first part will be a Phase I evaluation of the safety, tolerability, and feasibility of eliciting adequate IgG response with P10s-PADRE when administered in combination with SoC neoadjuvant chemotherapy. The study's second and third parts will respectively constitute Stages 1 and 2 of the Phase II primary-efficacy evaluation of Chemovax using a Simon optimal two-stage design

To evaluate the feasibility of eliciting adequate immune response with P10s-PADRE when it is administered in combination with neoadjuvant chemotherapy, we will sequentially evaluate different schedules of vaccination relative to chemotherapy, and stop evaluating as soon as we have identified a feasible schedule. To this end, we have defined five different Chemovax schedules, and named them A, B, C, D, and E;

Inclusion criteria

• Females of all races with clinical stage I, II, or III ER-positive, HER2 negative breast cancer who will undergo SoC neoadjuvant treatment.
• Age 18 years and older.
• ECOG Performance Status 0 or 1.
• White blood cell (WBC) count ≥ 3,000/mm3 within 3 weeks prior to registration.
• Platelet count ≥ 100,000/mm3 within 3 weeks prior to registration.
• Bilirubin ≤ 2 x institutional upper limit (IUL) of normal obtained within 3 weeks prior to registration.
• Serum glutamic-oxaloacetic transaminase (SGOT) or aspartate aminotransferase test (AST) ≤ 2 x IUL of normal obtained within 3 weeks prior to registration.
• Serum glutamic-pyruvic transaminase (SGPT) or alanine aminotransferase test (ALT) ≤ 2 x IUL of normal obtained within 3 weeks prior to registration.
• Serum creatinine ≤ 1.8 mg/dL obtained within 3 weeks prior to registration.
• Must sign an informed consent document approved by the UAMS IRB.

Exclusion criteria

• ER-negative, HER2-positive, inflammatory, metastatic, stage IV or recurrent breast cancer
• Active infection requiring treatment with antibiotics.
• Existing diagnosis or history of organic brain syndrome that might preclude participation in the full protocol.
• Existing diagnosis or history of significant impairment of basal cognitive function that might preclude participation in the full protocol.
• Other current malignancies. Subjects with prior history at any time of any in situ cancer, including lobular carcinoma of the breast in situ, cervical cancer in situ, atypical melanocytic hyperplasia or Clark I melanoma in situ or basal or squamous skin cancer are eligible, provided they are disease-free at the time of registration. Subjects with other malignancies are eligible if they have been continuously disease free for ≥ 5 years prior to the time of registration.
• Active autoimmune disorders or conditions of immunosuppression; Existing diagnosis or history of autoimmune disorders or conditions of immunosuppression that have been in remission for less than 6 months
• Treatment with corticosteroids, including oral steroids (i.e. prednisone, dexamethasone [except when used as an antiemetic in SoC therapy]), continuous use of topical steroid creams or ointments or any steroid-containing inhalers. Subjects who discontinue the use of these classes of medication for at least 6 weeks prior to registration are eligible if, in the judgment of the treating physician, the subject is not likely to require these classes of drugs during the treatment period. Replacement doses of steroids for subjects with adrenal insufficiency are allowed.
• Pregnancy or breastfeeding (due to the unknown effects of peptide/mimotope vaccines on a fetus or infant). Women of childbearing potential must have a negative urine pregnancy test within 72 hours prior to starting week 1 and must be counseled to use an accepted and effective method of contraception (including abstinence) while on treatment and for a period of 18 months after completing or discontinuing treatment. Accepted methods of contraception include tubal ligation, oral contraceptives, barrier methods, IUDs, and abstinence.
• Any other significant medical or psychiatric conditions, which, in the opinion of the enrolling investigator, may interfere with consent or compliance of the treatment regimen.
• Enrollment in any other clinical trial using investigational drug products or devices prior to first post-surgery study lab. Concurrent enrollment in observational studies is allowed.