IL-12 Gene and in Vivo Electroporation-Mediated Plasmid DNA Vaccine Therapy in Patients With Merkel Cell Cancer (MCC)

A Phase II Study of Intratumoral Injection of Interleukin-12 Plasmid and in Vivo Electroporation in Patients With Merkel Cell Carcinoma

This phase II trial studies the effectiveness of ImmunoPulse IL-12® in treating patients with Merkel cell cancer. ImmunoPulse IL-12® is the combination of intratumoral interleukin-12 gene (also known as tavokinogene telseplasmid [tavo]) and in vivo electroporation-mediated plasmid deoxyribonucleic acid [DNA] vaccine therapy (tavo-EP) administered using the OncoSec Medical System (OMS). Placing the gene for interleukin-12 into Merkel cells may help the mount an effective anti-tumor immune response to kill tumor cells.

Study Overview

• Status: Completed
• Conditions: Merkel Cell Carcinoma
• Intervention / Treatment: Biological: Tavokinogene Telseplasmid (tavo); Device: OncoSec Medical System (OMS)

Detailed Description

PRIMARY OBJECTIVES:

I. To measure the effect of intratumoral injection of tavo followed by in vivo electroporation (EP) (electroporation-mediated plasmid DNA vaccine therapy) on the local expression of interleukin-12 (IL-12) in the tumor microenvironment in patients with Merkel cell carcinoma (MCC).

SECONDARY OBJECTIVES:

I. To assess the safety of tavo-EP in MCC. II. To assess the clinical efficacy of this treatment approach in MCC. III. To assess the immunologic changes resulting from this treatment approach.

OUTLINE:

Patients receive tavo intratumorally (IT) and undergo electrical discharge via OMS around the tumor site for electroporation-mediated plasmid DNA vaccine therapy on days 1, 5, and 8. Patients with unresectable disease may receive a second course of treatment in 12 weeks. Patients with localized disease proceed to definitive treatment as determined by the treating physician starting 2-4 weeks after the first injection.

After completion of study treatment, patients are followed up at weeks 4-8 (for patients who received definitive treatment) or 12 (for patients with unresectable disease) and then annually for up to 5 years.

• Study Type: Interventional
• Enrollment (Actual): 15
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Washington
    • Seattle, Washington, United States, 98109
      • Fred Hutchinson Cancer Research Center/University of Washington Cancer Consortium

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Patients must have biopsy-confirmed Merkel cell carcinoma
• Patients must have at least one injectable lesion, defined as an easily palpable superficial lesion (cutaneous, subcutaneous or lymph nodal metastasis) that can be accurately localized, stabilized by palpation, and is superficial enough to enable intratumoral injection and electroporation; the injectable lesion must not be in close proximity to another tissue (e.g. nerve, bone) that could put patient safety at risk
• Eastern Cooperative Oncology Group (ECOG) performance status score 0 to 2
• Life expectancy of greater than three months
• Absolute neutrophil count > 1,000/uL
• Platelet count > 50,000/uL
• Creatinine =< 2.0 x upper limit of normal (ULN)
• Bilirubin =< 2.0 x ULN
• Prothrombin time (PT) and partial thromboplastin time (PTT) =< 1.5 x ULN
• Patients must be willing, at the time of the entry to the study, to undergo the pre-treatment fine needle aspiration (FNA) plus biopsy (if indicated) AND the post-treatment FNA plus biopsy (or surgery) of at least one injected lesion (FNA is essential to determine the primary endpoint of the study); NOTE: The pre-treatment biopsy will be obtained from a superficial not-to-be-injected lesion; the post-treatment biopsy of an injected lesion will be obviated if definitive surgical resection is planned
• The effects of this treatment approach on the developing human fetus are unknown; for this reason, women of child-bearing potential and men must agree to use adequate contraception (hormonal or barrier method of birth control; abstinence) prior to study entry and for the duration of study participation; should a woman become pregnant or suspect she is pregnant while participating in this study, she should inform her treating physician immediately
• Patients must have the ability to understand and the willingness to sign a written informed consent document
• Both men and women, and members of all races and ethnic groups are eligible for this trial

Exclusion Criteria:

• Patients who have had prior chemotherapy, investigational therapy or a major surgical procedure within 4 weeks or radiotherapy within 2 weeks prior to first day of treatment
• Patients must not be receiving concurrently any other anti-cancer treatment (including topical agents such as imiquimod) or investigational agents, which could potentially interfere with the study treatment and/or study endpoints
• Patients with active untreated brain metastases will be excluded
• Pregnant or breast feeding women are excluded because effects of this treatment on the fetus or passage through milk are unknown
• Patients with electronic pacemakers or defibrillators or those with a history of life threatening cardiac arrhythmia or uncontrolled seizure disorder are excluded
• Use of any immunosuppressive treatments including corticosteroids, cyclosporine, mycophenolate mofetil et cetera, within 4 weeks prior to Day 1 of treatment will not be allowed; NOTE: Patients on topical or physiologic doses (for hormone-replacement therapy) of corticosteroids will be allowed
• Patients, who are judged to be immunosuppressed due to uncontrolled human immunodeficiency virus (HIV) infection, severe uncontrolled diabetes, concurrent hematological malignancy, or other comorbidities, will be excluded
• Uncontrolled intercurrent illness including, but not limited to, ongoing or active serious infection, symptomatic congestive heart failure, unstable angina pectoris, serious autoimmune conditions or psychiatric illness/social situations that would limit compliance with study requirements
• Patients receiving concurrent therapeutic-dose anticoagulation will be excluded

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Cohort A: Tavo-EP; Patients in Cohort A received one cycle (3 daily treatments on Days 1, 5, and 8) of intra-tumoral injection(s) of tavo at a fixed dose of 0.5 mg/mL (up to 4 tumor sites) followed immediately by in vivo electroporation, after which they proceeded to definitive treatment (surgery and/or radiation therapy) which started between 2 and 4 weeks after the first injection.	Biological: Tavokinogene Telseplasmid (tavo); Patients received intratumoral injection(s) of tavo.; Other Names: pIL-12; interleukin-12 gene; IL-12 gene; plasmid DNA encoding human interleukin-12; plasmid IL-12; Device: OncoSec Medical System (OMS); Electroporation via OMS was performed immediately following intratumoral injection of tavo. A sterile applicator containing 6 stainless steel electrodes arranged in a circle were placed around the tumor. The applicator was connected to the OMS power supply and six pulses were administered to each tumor lesion at the approximate point of tavo injection.; Other Names: MedPulser
Experimental: Cohort B: Tavo-EP; Patients in Cohort B received up to 4 cycles (3 daily treatments on Days 1, 5, and 8, per cycle) of intra-tumoral injection(s) of tavo at a fixed dose of 0.5 mg/mL (up to 4 tumor sites) followed immediately by in vivo electroporation, with 12 planned weeks between each cycle, lasting up to 12 months.	Biological: Tavokinogene Telseplasmid (tavo); Patients received intratumoral injection(s) of tavo.; Other Names: pIL-12; interleukin-12 gene; IL-12 gene; plasmid DNA encoding human interleukin-12; plasmid IL-12; Device: OncoSec Medical System (OMS); Electroporation via OMS was performed immediately following intratumoral injection of tavo. A sterile applicator containing 6 stainless steel electrodes arranged in a circle were placed around the tumor. The applicator was connected to the OMS power supply and six pulses were administered to each tumor lesion at the approximate point of tavo injection.; Other Names: MedPulser

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of Participants Who Experienced At Least 2-Fold Increase in Expression of IL-12 Protein in the Tumor Tissue After Intratumoral (IT) pIL-12 Injections and In Vivo Electroporation	The MAGPIX assay was used to assess differential expression of hIL-12 in patient tumor tissue before and after treatment with intratumoral (IT) tavo injections and in vivo electroporation (EP). Expression of hIL-12 was used to identify patients who met the primary endpoint of a 2-fold or higher increase in expression of hIL-12 in tumors after treatment. Fold change was taken as a comparison of hIL-12 expression at Week 3:pre-treatment, Week 6:pre-treatment, Week 8:pre-treatment, or Week 13:pre-treatment over baseline (pre- treatment). The fold change was calculated as log2 (time point/baseline).	Pre-treatment up to Week 13

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of Participants With Adverse Events (AEs) and Serious Adverse Events (SAEs)	An AE was any untoward medical occurrence in a patient or clinical investigation participant administered a pharmaceutical product, medical treatment or procedure and which did not necessarily have to have had a causal relationship with this treatment. An adverse event could have, therefore, been any unfavorable and unintended sign (including an abnormal laboratory finding, for example), symptom, or disease temporally associated with the use of a medicinal product, medical treatment or procedure whether or not considered related to the medicinal product. An SAE was defined an any untoward medical occurrence that at any dosage resulted in one or more of the following: death, A life-threatening adverse event (real risk of dying), inpatient hospitalization or prolongation of existing hospitalization, persistent or significant disability/incapacity, congenital anomaly, required intervention to prevent permanent impairment of damage.	From signing of informed consent to 8 weeks after the last dose of study treatment (up to 15 months)
Objective Response Rate (ORR) in Injected and Non-injected (Distant) Lesions	ORR is defined as the percentage of participants with evaluable lesions that achieved a complete response (CR) or partial response (PR) as assessed by the investigator using Response Evaluation Criteria In Solid Tumors (RECIST) version 1.1. CR: Disappearance of all target lesions, non-target lesions, no new lesions, and normalization of tumor marker level. PR: At least a 30% decrease in the sum of diameters of target lesions, no progression in non-target lesion, and no new lesions. The same method was used to assess response rate for treated lesions and response rate for non-treated lesions. The best response rate for non-treated lesions was based on the number of patients who had at least one non-treated lesion.	3-4 weeks after the first dose in each cycle and then every 3 months until disease progression, death or withdrawal of consent (up to 15 months)
Time to Progression (TTP)	TTP is defined as the number of days between the treatment initiation date (Study Day 1) and the earliest date of documented disease progression as defined by RECIST 1.1 or death that is not associated with prior disease progression. Progression is defined using Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1), as a 20% increase in the sum of the longest diameter of target lesions, or a measurable increase in a non-target lesion, or the appearance of new lesions.	3-4 weeks after the first dose in each cycle and then every 3 months until disease progression, death or withdrawal of consent (up to 15 months)
Overall Survival	Overall survival is defined as the time in days from the date of first study drug administration to the date of death.	From the start of study treatment until death (up to 15 months)
Immunologic Effects of IT pIL-12 Injection and In Vivo EP Measured By: Percentage of Participants With a Positive Fold Change (Log2) in IL-12A Messenger Ribonucleic Acid (mRNA) for Patient Pre- and Post IT pIL 12 EP	Nanostring analysis was performed to determine the expression (mRNA) of IL-12. For each study patient, the fold change (log2 transformed) in IL-12A mRNA as measured by Nanostring was determined using the pre-treatment (screening) biopsy as a reference for the post treatment biopsy. A log2 fold change >=1 is a positive result.	Pre-treatment up to Week 13
Local Regression Rate	Local regression rate is defined as the percentage of participants with ≥30% regression (decrease in size) of at least one assessed local (injected) lesion.	3-4 weeks after the first dose in each cycle and then every 3 months until disease progression, death or withdrawal of consent (up to 15 months)
Distant Regression Rate	Distant regression rate is defined as the percentage of participants with ≥30% regression (decrease in size) of at least one assessed distant (non-injected) lesion.	3-4 weeks after the first dose in each cycle and then every 3 months until disease progression, death or withdrawal of consent (up to 15 months)

Collaborators and Investigators

• Sponsor: OncoSec Medical Incorporated
• Collaborators: National Cancer Institute (NCI)
• Investigators: Principal Investigator: Shailender Bhatia, Fred Hutchinson Cancer Research Center/University of Washington Cancer Consortium

Study record dates

Study Major Dates

• Study Start (Actual): January 3, 2012
• Primary Completion (Actual): April 10, 2015
• Study Completion (Actual): April 10, 2015

Study Registration Dates

• First Submitted: September 23, 2011
• First Submitted That Met QC Criteria: September 26, 2011
• First Posted (Estimate): September 27, 2011

Study Record Updates

• Last Update Posted (Actual): May 15, 2023
• Last Update Submitted That Met QC Criteria: May 11, 2023
• Last Verified: May 1, 2023

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Virus Diseases; Infections; Neoplasms by Histologic Type; Neoplasms; Adenocarcinoma; Neoplasms, Glandular and Epithelial; Neuroectodermal Tumors; Neoplasms, Germ Cell and Embryonal; Neoplasms, Nerve Tissue; DNA Virus Infections; Tumor Virus Infections; Neuroendocrine Tumors; Polyomavirus Infections; Carcinoma, Neuroendocrine; Carcinoma; Carcinoma, Merkel Cell; Physiological Effects of Drugs; Antineoplastic Agents; Immunologic Factors; Angiogenesis Inhibitors; Angiogenesis Modulating Agents; Growth Substances; Growth Inhibitors; Adjuvants, Immunologic; Interleukin-12
• Other Study ID Numbers: OMS-I110; P30CA015704 (U.S. NIH Grant/Contract); NCI-2011-01221 (Registry Identifier: CTRP (Clinical Trial Reporting Program))

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED