Safety and Efficacy of Repeat Administration of Ad/PNP and Fludarabine Phosphate in Patients With Local Head/Neck Cancer

• ClinicalTrials.gov Identifier: NCT03754933
• Recruitment Status: Recruiting
• First Posted: November 27, 2018
• Last Update Posted: August 31, 2023
• Sponsor: GeoVax, Inc.
• Collaborators: Stanford University; Emory University; Thomas Jefferson University
• Information provided by (Responsible Party): GeoVax, Inc.

Study Description

Brief Summary:

Primary Objective: The primary objective of the study is to evaluate the safety of repeat administration of a dose level of Ad/PNP plus fludarabine phosphate (F-araAMP) which demonstrated anti-tumor activity in patients with advanced head and neck cancer in a completed phase I study.

Secondary Objective: The secondary objective is to evaluate the antitumor activity of repeat administration of Ad/PNP plus F-araAMP.

FDA Office of Orphan Drugs Division is a source of funding for the overall project.

Condition or disease	Intervention/treatment	Phase
Recurrent Head and Neck Cancer	Biological: Ad/PNP; Drug: Fludarabine Phosphate	Phase 1; Phase 2

Detailed Description:

1. Mechanism of action. The study drug, Ad/PNP-F-araAMP (Fludarabine phosphate) consists of a nonreplicating adenoviral vector expressing the E. coli purine nucleoside phosphorylase (PNP) injected intratumorally followed by intravenous administration of F-araAMP. This combination generates 2-fluoroadenine (F-Ade) within the tumor resulting in focal chemotherapeutic activity.

   F-araAMP is an agent that is rapidly cleaved by plasma phosphatases to fludarabine, which is the primary circulating form of the drug and has activity against certain hematological malignancies, but not against solid tumors such as head and neck squamous cell carcinoma (HNSCC). Fludarabine (F-araA) is an adenosine analog and substrate for E. coli PNP, which cleaves the glycosidic bond of F-araA to generate F-Ade. The F-Ade metabolite has shown pronounced activity against human tumor xenografts in mice.

   Many refractory tumors are refractory precisely because they have a very low growth fraction, i.e., a relatively small percentage of tumor cells dividing at any particular point in time. In nonclinical studies, significant in vivo antitumor activity has been demonstrated by F-Ade generation from F-araAMP in tumors in which 2.5 to 10% of cells express the E. coli PNP gene. In addition, anti-tumor effect was seen in patients with advanced solid tumors (melanoma and head and neck cancer) in the higher dose cohorts during a Phase 1 study (see next section).

2. Tumor response with Ad/PNP-F-araAMP in Phase 1 Study. The safety and efficacy of Ad/PNP-F-araAMP has been evaluated in a Phase 1 study, PNP-001. Four escalating dose levels were evaluated in 10 subjects with head and neck cancer and 2 subjects with melanoma; clinical activity was observed at the highest dose levels following 3 intratumoral injections of Ad/PNP over 2 days and IV F-araAMP phosphate over 3 days. The overall response rate (CR+PR) was approximately 67% in the 2 highest dose cohorts, Cohorts 3 and 4. Results suggest a dose response effect. The duration of response in the injected tumor was limited, with 4 of 5 responding tumors having disease progression of the injected lesion prior to last follow-up on Day 56, suggesting that repeat administration should be evaluated. Ad/PNP + F-araAMP was well tolerated. No subject experienced a dose-limiting toxicity and none of the subjects discontinued study treatment. Overall, the activity and safety profile of Ad/PNP seen in the Phase 1 study supports further clinical evaluation of repeat administration of Ad/PNP (IT) and F-araAMP phosphate infusion for patients with HNSCC.
3. Purpose of the Study. Based upon the tumor response seen with a single administration of the two highest dose levels of Ad/PNP-F-araAMP in the Phase 1 study, PNP plans to investigate the safety and assess anti-tumor activity of repeat cycles of injection of Ad/PNP + F-araAMP in patients with advanced head and neck cancer. Subjects in the study will have RECIST 1.1 measurable HNSCC which is amenable to local injection for which there is no effective curative or palliative treatment option. This study population was selected since results from this Phase 1/2 trial are intended to support the safety of repeat dosing in further clinical investigation.
4. Study Design. The trial is designed as a single-arm study to evaluate the safety of repeat cycles of Ad/PNP and F-araAMP in patients with recurrent HNSCC with tumor(s) accessible for injection. Ad/PNP will be injected intratumorally twice on Day 1 and once on Day 2 followed by infusion of F-araAMP daily on Days 3, 4, and 5. Subjects will receive repeat administration of Ad/PNP-F-araAMP every 4 weeks (i.e., each cycle) for 5 cycles or until injected tumor progresses, unacceptable toxicity occurs, no tumor is present for injection, or patient death. Tumor response in the injected tumor(s) will be assessed by physical examination as well as by radiographic imaging. All subjects will be monitored for adverse events during study participation.

Study Design

• Study Type: Interventional (Clinical Trial)
• Estimated Enrollment: 10 participants
• Allocation: N/A
• Intervention Model: Single Group Assignment
• Masking: None (Open Label)
• Primary Purpose: Treatment
• Official Title: Phase 1/2, Open-label Study Evaluating Safety of Repeat Administration of Ad/PNP-F-araAMP (Ad/PNP Administered Intratumorally Followed by Intravenous Fludarabine Phosphate) in Subjects With Recurrent, Local Head and Neck Cancer
• Actual Study Start Date: February 11, 2019
• Estimated Primary Completion Date: May 2024
• Estimated Study Completion Date: August 2025

Arms and Interventions

Arm	Intervention/treatment
Experimental: Ad/PNP + fludarabine phosphate, 5 cycles	Biological: Ad/PNP; Ad/PNP is a replication defective adenoviral vector expressing E. coli Purine Nucleoside Phosphorylase; Other Name: Gedeptin; Drug: Fludarabine Phosphate; Fludarabine phosphate is an anticancer agent currently used to treatment patients with chronic lymphocytic leukemia.; Other Name: Fludara

Outcome Measures

Primary Outcome Measures :

1. Safety as measured by the number of adverse events Grade 2 and above that are considered by investigator to be definitely, probably, or possibly related to study treatment, graded according to Common Terminology Criteria for Adverse Effects v. 4.0 [ Time Frame: up to 60 days ]
   Adverse events Grade 2 and above that are considered by investigator to be definitely, probably, or possibly related to study treatment will be collected from initial dose through 60 days after last dose of study drug. Outcome measure will be reported as the number of events for each dose group, and all safety events will be summarized with descriptive statistics.

Secondary Outcome Measures :

1. Best Overall Response (ORR) per RECIST 1.1. [ Time Frame: Six months ]
   Best durable overall response (ORR) defined as CR or partial response determined by RECIST 1.1 persisting for at least 4 weeks
2. Progression Free Survival (PFS) [ Time Frame: Six months ]
   Progression Free Survival (PFS) defined as time from first intratrumoral injection to date of progression or to death, whichever occurs first.
3. Duration of treatment response [ Time Frame: Six months ]
   Duration of treatment response defined as time from first documentation of CR or PR until first occurrence of disease progression or death.

Eligibility Criteria

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

Criteria

Inclusion Criteria:

1. Provided Informed Consent
2. Age ≥ 18 years
3. Patients with histologically or cytologically confirmed diagnosis of recurrent cancer of the head and neck region for whom there is no curative treatment option. For the purposes of trial eligibility, cancers of the head and neck shall include, in addition to head and neck squamous cell carcinoma (HNSCC), cutaneous squamous cell primary sites and squamous cell carcinoma of unknown primary presenting with neck lymph nodal disease, as well as nasopharyngeal carcinoma, and salivary gland tumors.
4. All standard or approved treatment options that would provide substantive palliation must have failed, been exhausted, or patient not eligible or willing to use them (for example neuropathy, nephropathy , or hearing loss precluding the use of cisplatin)
5. Tumor mass (primary tumor and/or lymphadenopathy) measurable by Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and technically suitable for intratumoral injections (otolaryngologist will determine feasibility). Patients with nodal disease (or metastatic disease) that is needle accessible are eligible. Patients with additional tumors (including distant metastatic disease) beyond the intratumoral injection accessible tumor(s) that are not accessible for intratumoral injection are eligible ONLY if the patient has no other treatment option for the metastatic disease and treatment of local disease may provide the patient some benefit or palliation.
6. Eastern Cooperative Oncology Group performance status of ≤ 2
7. In the judgment of the Investigator, the patient has recovered sufficiently from any previous significant therapy side effects or toxicities prior to Ad/PNP administration.
8. Absolute neutrophil count ≥ 1,500 cells/ul; hemoglobin ≥ 9 g/dl, platelets ≥ 100,000/ul
9. Serum creatinine ≤ 1.5 mg/dl, or calculated creatinine clearance ≥ 60 ml/min
10. Bilirubin ≤ upper limit of normal, alanine aminotransferase ≤ 1.5 x upper limit of normal and/or aspartate aminotransferase ≤ 1.5 x upper limit of normal, alkaline phosphatase ≤ 2.5 x upper limit of normal
11. Prothrombin time (PT)/international normalized ratio (INR) ≤ 1.5 x upper limit of normal
12. Activated partial thromboplastin (aPTT) time ≤ 1.5 x upper limit of normal
13. Female patients must have a negative urine or serum pregnancy at screening (pregnancy test is not required for patients with bilateral oophorectomy and/or hysterectomy or for those patients who are > 1 year postmenopausal)
14. All patients of reproductive potential must agree to use a medically acceptable form of contraception (eg, hormonal birth control, double-barrier method) or abstinence.

Exclusion Criteria:

1. Prior history or current diagnosis of leukemia
2. Have received any gene therapy products or oncolytic viral therapy
3. Receiving allopurinol
4. Received an investigational drug within 30 days prior to first injection of Ad/PNP
5. Received radiation treatment < 4 weeks prior to first injection of Ad/PNP, and does not have any RECIST 1.1 evaluable lesions that are outside the radiation field. (If the patient has RECIST 1.1 evaluable lesions outside the radiation field then they can be included.)
6. Received chemotherapy (systemic anticancer treatment) < 4 weeks prior to first injection of Ad/PNP and has not recovered from all the related side effects. (If the patient has recovered from all related side effects or has reached a new baseline, then they may begin receiving treatment at sooner than 4 weeks)
7. Have significant baseline neuropathy (> Grade 2 based on Common Terminology Criteria for Adverse events [CTCAE] v5.0)
8. Uncontrolled intercurrent disease (e.g., diabetes, hypertension, thyroid disease, active infection)
9. Had within 6 months prior to enrollment: Myocardial infarction, cerebral vascular accident, uncontrolled congestive heart failure, significant liver disease, unstable angina
10. Fever (temperature > 38.1 degrees C orally)
11. Receiving chronic systemic corticosteroids (> 3 weeks) or any chronic immunosuppressive medications within 14 days prior to first injection of Ad/PNP. Subjects receiving short courses of corticosteroids are considered eligible for the study.
12. Receiving anticoagulants other than those to maintain patency of venous lines
13. Women who are pregnant or breast feeding
14. History of HIV infection. No requirement for testing.

Contacts and Locations

Contacts

Contact: Chief Medical Officer; 678-384-7220; info@geovax.com

Contact: Director Clinical Operations

Locations

United States, California

Stanford University; Recruiting

Stanford, California, United States, 94305

Contact: Luis Martinez Ramirez 650-736-2344 martluis@stanford.edu

Contact: A. Dimitrios Colevas, MD 650-724-9707 colevas@stanford.edu

United States, Georgia

Winship Cancer Institute - Emory University School of Medicine; Recruiting

Atlanta, Georgia, United States, 30322

Contact: Madison Miller Stallings 404-686-1794 madison.miller.stallings@emory.edu

Contact: Nicole C. Schmitt, MD, FACS 404-778-1900 nicole.cherie.schmitt@emory.edu

United States, Pennsylvania

Thomas Jefferson University; Recruiting

Philadelphia, Pennsylvania, United States, 19107

Contact: Camilo Henao, MPH 215-955-9959 Camilo.Henao@jefferson.edu

Contact: Joseph M Curry, MD, FACS 215-955-6760 joseph.curry@jefferson.edu

Sponsors and Collaborators

GeoVax, Inc.

Stanford University

Emory University

Thomas Jefferson University

Investigators

• Principal Investigator: A. Dimitrios Colevas, MD; Stanford University

More Information

Publications:

Parker WB, Sorscher EJ. Use of E. coli Purine Nucleoside Phosphorylase in the Treatment of Solid Tumors. Curr Pharm Des. 2017 Nov 8:10.2174/1381612823666171109101851. doi: 10.2174/1381612823666171109101851. Online ahead of print.

Rosenthal EL, Chung TK, Parker WB, Allan PW, Clemons L, Lowman D, Hong J, Hunt FR, Richman J, Conry RM, Mannion K, Carroll WR, Nabell L, Sorscher EJ. Phase I dose-escalating trial of Escherichia coli purine nucleoside phosphorylase and fludarabine gene therapy for advanced solid tumors. Ann Oncol. 2015 Jul;26(7):1481-7. doi: 10.1093/annonc/mdv196. Epub 2015 Apr 21.

• Responsible Party: GeoVax, Inc.
• ClinicalTrials.gov Identifier: NCT03754933
• Other Study ID Numbers: PNP-002; R01FD005746-01A1 ( U.S. FDA Grant/Contract ); 14271 ( Registry Identifier: IND )
• First Posted: November 27, 2018
• Last Update Posted: August 31, 2023
• Last Verified: August 2023

Individual Participant Data (IPD) Sharing Statement:

• Plan to Share IPD: No

• Studies a U.S. FDA-regulated Drug Product: Yes
• Studies a U.S. FDA-regulated Device Product: No
• Product Manufactured in and Exported from the U.S.: No

Keywords provided by GeoVax, Inc.:

Fludarabine; Adenovirus; Head & neck squamous cell carcinoma

Additional relevant MeSH terms:

Head and Neck Neoplasms; Neoplasms by Site; Neoplasms; Fludarabine; Fludarabine phosphate; Antineoplastic Agents; Antimetabolites, Antineoplastic; Antimetabolites; Molecular Mechanisms of Pharmacological Action; Immunosuppressive Agents; Immunologic Factors; Physiological Effects of Drugs