Title
PolyPEPI1018 Vaccine and CDx for the Treatment of Metastatic Colorectal Cancer (OBERTO)
Safety, Tolerability, Immunogenicity and Efficacy of Multiple PolyPEPI1018 Vaccinations as an Add-on Immunotherapy to the Standard-of-Care Maintenance Therapy in Subjects With Metastatic Colorectal Cancer
Phase
Phase 1/Phase 2Lead Sponsor
Treos BioStudy Type
InterventionalStatus
Completed Results PostedIndication/Condition
Colorectal CancerIntervention/Treatment
PolyPEPI1018 CRC VaccineStudy Participants
11Phase I/II clinical trial investigates the safety, tolerability, immunogenicity and preliminary efficacy of multiple doses of PolyPEPI1018 CRC vaccine as an add-on treatment to the standard-of-care maintenance therapy in patients with metastatic colorectal cancer. Clinical responses will be evaluated by indiction of T cell responses, T lymphocyte infiltration in accessible biopsy sites, and by objective tumor responses. This study will also explore the accuracy of the predicted T cell responses in each patient using the candidate companion diagnostic test and the correlations between clinical responses and predicted T cell responses.
This is a Phase I/II, open-label, single-arm, multicenter study to evaluate the safety, tolerability, immunogenicity and efficacy of a multiple subcutaneous injection of PolyPEPI1018 as an add-on immunotherapy to the standard-of-care maintenance therapy in approximately 15 subjects with metastatic colorectal cancer.
The first part of the study investigates the administration of a single vaccine dose during 12-week follow-up period on an outpatient basis. Screening is performed in parallel with the subject's completion of the standard-of-care first-line treatment and initiation of the standard-of-care maintenance treatment. A single dose of PolyPEPI1018 is administered after the subject initiates the maintenance regimen, and within 3 weeks after the eligibility CT scan was performed. Subjects are monitored every 3 weeks for 12 weeks.
The second part of the study investigates the administration of 3 vaccine doses (Weeks 0, 13, 26) then 12 weeks follow-up on an outpatient basis.
Colorectal Cancer Vaccine
The vaccine contains 6 synthetic peptides mixed with the adjuvant Montanide™. The peptides were selected to induce T cell responses against 12 dominant epitopes from 7 cancer testis antigens (CTAs), which are the most frequently expressed CTAs in colorectal cancer. The 6 peptides were optimized to induce long lasting CRC specific T cell responses.
Inclusion Criteria: Male or female subjects, 18-75 years of age at time of Screening who provide written informed consent prior to initiation of any study procedure Histologically confirmed metastatic adenocarcinoma originating from the colon or the rectum Presence of at least 1 measurable reference lesion according to the Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 criteria Experienced PR or stable disease during first-line treatment with a systemic chemotherapy regimen and 1 biological therapy regimen Maintenance therapy with a fluoropyrimidine (5-fluorouracil or capecitabine) plus the same biologic agent (bevacizumab, cetuximab or panitumumab) used during induction, scheduled to initiate prior to the first day of treatment with the study drug No more than 1 line of chemotherapy regimen for mCRC (adjuvant therapy for non-metastasized disease is allowed if terminated more than 6 months before Screening and without recurrence within 6 months after the end of adjuvant treatment) Last CT scan at 3 weeks or less before the first day of treatment Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 Women of childbearing potential must agree to appropriately use an effective form of contraception (failure rate of <1% per year) for 3 months from the day of the treatment. An effective form of contraception is defined as using hormonal contraceptives or an intrauterine device combined with at least 1 of the following forms of contraception: a diaphragm, cervical cap or condom Men must agree to use an effective form of contraception (as defined above), and not donate sperm for 3 months from the day of the treatment White blood cell count ≥3.0 × 109/L with neutrophils ≥1.5 × 109/L Platelets ≥100 × 109/L, hemoglobin ≥5.6 mmol/L (corresponding to 9 g/dL) Serum bilirubin ≤1.5 × upper limit of normal (ULN) set by the site Alanine amino transferase (ALAT) and aspartate amino transferase (ASAT) ≤2.5 × ULN in the absence of liver metastases. ALAT and ASAT ≤5 × ULN set by the site in the presence of liver metastases Serum creatinine ≤1.5 × ULN set by the site and creatinine clearance >30 mL/min using Cockroft formula Relevant toxicities of prior therapies must have resolved, except for oxaliplatin-related neuropathy or alopecia Anticipated life expectancy ≥6 months Subject is willing and able to comply with the requirements of the protocol Exclusion Criteria: Received chronic systemic immune therapy or immunosuppressant medication other than steroids within the last 6 weeks prior to start of study treatment Received continuous systemic steroid treatment within the last 2 weeks prior to start of study treatment Colorectal cancer with documented high microsatellite instability (MSI-H) Colorectal cancer with documented BRAF mutations Pre-existing systemic autoimmune or antibody-mediated diseases or immune deficiency diseases Central nervous system (CNS) metastases Active or uncontrolled severe infections or undiagnosed febrile condition >38ºC Acute or subacute intestinal obstruction or history of chronic intestinal inflammatory diseases Symptomatic peritoneal carcinomatosis Peritonitis Serious, non-healing wounds, ulcers or bone fractures Nephrotic syndrome Arterial thromboembolisms or severe hemorrhages within 6 months before study enrolment (except bleeding tumor before tumor resection surgery) Hemorrhagic diathesis or thrombotic tendency Major surgery or radiotherapy within 12 weeks prior to the study treatment or anticipation of needing such procedure during the study period Uncontrolled pleural effusion, pericardial effusion or ascites requiring repeated drainage more than once every 28 days Participants with active malignancy (other than colorectal cancer) or a prior malignancy within the past 12 months Participant with myocardial infarction within 6 months prior to enrollment or New York Heart Association Class III or IV heart failure, uncontrolled angina, severe uncontrolled ventricular arrhythmias or electrocardiographic evidence of acute ischemia or active conduction system abnormalities. Prior to the first dose of study treatment, any electrocardiogram (ECG) abnormality at Screening must be documented by the investigator as not medically relevant Administration of a live, attenuated vaccine within 4 weeks before randomization or anticipation of a live attenuated vaccine will be required during the study Participant has participated in another clinical study involving an investigational product (IP) or investigational device within 30 days prior to enrollment or is scheduled to participate in another clinical study involving an IP or investigational device during the course of this study Known hypersensitivity to any component of the investigational drug If female, participant is pregnant (exclusion confirmed with beta-human chorionic gonadotropin [hCG] test) or lactating at the time of enrollment, or has plans to become pregnant or start breastfeeding during the study Pre-existing alcohol or drug abuse Medical or mental impairments which make it impossible to obtain the patient's consent or to conduct the study A significant concomitant medical condition which the clinical investigator believes precludes the patient from enrolling in the study Absent or limited legal competence
| Event Type | Organ System | Event Term | Single Dose of PolyPEPI1018 CRC Vaccine | Multiple Dose of PolyPEPI1018 CRC Vaccine |
|---|
Occurrence of at least 1 ≥Grade 4 local adverse event (AE) or 1 ≥Grade 3 systemic AE and/or signs/symptoms, lab toxicities, and/or clinical events that is probably or definitely related to study treatment
Measured CD4+ and CD8+ T cell responses from each subject for each antigen of the vaccine
Epitopes restricted to multiple HLA class I alleles (Personal Epitope, PEPI) of a subject were predicted. PEPIs determined for each vaccine antigen can predict the antigen-specific T cell responses for each patient.
Per Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) for target lesions and assessed by MRI: Complete Response (CR), Disappearance of all target lesions; Partial Response (PR), >=30% decrease in the sum of the longest diameter of target lesions; Overall Response (OR) = CR + PR. CT scans were performed at screening and weeks 6,12 after each vaccination. The objective response were based on for each subject's last CT scan evaluation.
Per Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) for target lesions and assessed by MRI: Complete Response (CR), Disappearance of all target lesions; Partial Response (PR), >=30% decrease in the sum of the longest diameter of target lesions; Stable Disease (SD) <30% increase compare to smallest sum of the longest diameter of target lesions. CT scans were performed at screening and weeks 6,12 after each vaccination. The DCR were counted as the best response (PR or SD) for each subject's during the trial.
Assessments of TILs was performed using IHC (Immunoscore CR) CD3/CD8 testing on liver biopsy tissue samples obtained from subjects during a time course from baseline until the Last Visit. The CD3+ and CD8+ cell densities were determined in the core tumor and invasive margin using Immunohistochemistry (IHC) staining followed by digital pathology.
