A Phase 1 interventional study of Laboratory Biomarker Analysis and Modified Vaccinia Virus Ankara Vaccine Expressing p53 in Adult Solid Neoplasm, Bladder Carcinoma and Colon Carcinoma, sponsored by City of Hope Medical Center. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-01-28.
Sponsored by City of Hope Medical Center · Phase 1, Interventional, and Treatment
This phase I trial studies the side effects of vaccine therapy and pembrolizumab in treating patients with solid tumors that have spread to other places in the body and usually cannot be cured or controlled with treatment, that have failed prior therapy, and that cannot be removed by surgery. Vaccines made from a gene-modified virus may help the body build an effective immune response to kill tumor cells. Monoclonal antibodies, such as pembrolizumab, may block tumor growth in different ways by targeting certain cells. Giving vaccine therapy together with pembrolizumab may be a better treatment in patients with solid tumors.
PRIMARY OBJECTIVES:
I. To determine the safety and tolerability of combined p53MVA vaccine (modified vaccinia virus Ankara vaccine expressing p53) and pembrolizumab that are well-tolerated in patients with refractory, tumor protein 53 (p53) over expressing cancer.
SECONDARY OBJECTIVES:
I. To evaluate clinical response and anti-p53 T cell immune responses.
OUTLINE: Patients receive pembrolizumab intravenously (IV) over 30 minutes followed by modified vaccinia virus Ankara vaccine expressing p53 subcutaneously (SC) at least 30 minutes later once in weeks 1, 4, and 7.
Patients may receive additional doses of pembrolizumab in weeks 10, 13, 16, and 19, for a maximum of 7 doses if there are no signs of progressive disease. Treatment continues in the absence of disease progression or unacceptable toxicity.
After completion of study treatment, patients are followed up periodically.
1,616 studies on the registry are indexed under Urinary Bladder Neoplasms; 421 are open to participants now.
This study's enrollment of 11 is below the median of 60 across 1,163 interventional studies indexed under Urinary Bladder Neoplasms.
Browse Urinary Bladder Neoplasms studies →City of Hope Medical Center is the lead sponsor of 670 studies on the registry; 181 are open to participants now.
Of its 30 completed or terminated interventional studies of FDA-regulated products, 12 (40%) have results posted.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Patients receive pembrolizumab IV over 30 minutes followed by modified vaccinia virus Ankara vaccine expressing p53 SC at least 30 minutes later once in weeks 1, 4, and 7. Patients may receive additional doses of pembrolizumab in weeks 10, 13, 16, and 19, for a maximum of 7 doses if there are no signs of progressive disease. Treatment continues in the absence of disease progression or unacceptable toxicity.
Other: Laboratory Biomarker Analysis · Biological: Modified Vaccinia Virus Ankara Vaccine Expressing p53 · Biological: Pembrolizumab
Correlative studies
Given SC
Also known as: MVA-p53 Vaccine, MVAp53 Vaccine
Given IV
Also known as: Keytruda, Lambrolizumab, MK-3475, SCH 900475
Tolerability of combined modified vaccinia virus Ankara vaccine expressing p53 and pembrolizumab, using the National Cancer Institute Common Terminology Criteria for Adverse Events version 4.3
Time frame: Up to week 20
Clinical responses, assessed by the modified Response Evaluation Criteria in Solid Tumors (RECIST)
Evaluated using immune-related response criteria (irRECIST, irRC).
Time frame: Up to week 19
T cell reactivity to p53, assessed by flow cytometry
Immunosuppressive cell types (MDSC, Tregs) and other selected lymphocyte subsets and markers including PD-1, PDL-1 and PDL-2 will be quantified. The Wilcoxon rank-sum test will be used, and are based on residual re-sampling simulations based on historical AUC values (subtracting baseline) and a hypothesized increase in that AUC.
Time frame: Up to week 19
This study is active, not recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
City of Hope Medical Center