Phase II Study of RP2 as Immunoprevention in High-Risk Oral Precancerous Disease

Phase 2

Recruiting

• Conditions: High-Risk Oral Precancerous Disease
• Interventions: Biological: RP2 Injection

• Registration Number: NCT06623110
• Lead Sponsor: Glenn J. Hanna

Brief Summary

The goal of this study is to understand the safety, tolerability, and potential efficacy of an injected immune therapy called RP2 to treat oral precancer conditions and prevent progression to an oral cancer.

The name of the study drug involved in this study is:

-RP2 (a genetically modified live Herpes Simplex V-1 strain)

Detailed Description

This is a single-arm, open-label, single-center phase 2 study evaluating RP2 as a therapy for participants with high-risk oral precancerous diseases (OPDs).

RP2 is a herpes simplex virus (a viral infection commonly known as the "cold sore virus") that has been changed to grow in and destroy cancer cells and to activate (turn on) the human immune system to attack the cancer cells. RP2 is made using herpes simplex virus type-1 (HSV-1) viral carrier which has been changed such that it is unlikely to cause human disease

The U.S. Food and Drug Administration (FDA) has not approved RP2 as a treatment for high-risk oral precancerous disease.

The study procedures for this research study include a screening visit to determine eligibility, in-clinic visits, blood tests, urine tests, and mucosal punch biopsy,

Participants will receive the study drug every 2 weeks and will be followed for up to 2 years.

It is expected that up to 25 people will take part in this research study.

Replimune, Inc. is supporting this study by supplying the drug, RP2, and providing funding.

Study Timeline

• Study First Submitted: 2024-09-30
• Study First Submitted QC: 2024-09-30
• Study First Posted: 2024-10-02
• Study Start: 2025-01-01
• Status Verified: 2025-04
• Last Update Submitted: 2025-04-14
• Last Update Posted: 2025-04-17
• Primary Completion: 2027-01-01
• Study Completion: 2029-01-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 25

Inclusion Criteria

• Patients with a diagnosis of high-risk OPD defined by any of the following:

  • Proliferative leukoplakia (PL)
  • Localized leukoplakia showing at least moderate dysplasia not treated with surgery
  • Erythroplakia (regardless of dysplasia)
  • High-risk LOH profile: 9p21 or CDKN2A or MTAP loss; regardless of personal oral cancer history
  • Any degree of dysplasia with a known TP53 mutation
  • A history of treated stage 1 or 2 (AJCC 2017 8th edition) HNSCC with at least moderate dysplasia at the resection margins or known 9p21 loss or a known TP53 mutation

• No evidence of head and neck cancer recurrence within the last 3 months (if applicable).

• Willing to provide blood and tissue for diagnostic biopsies.

• At least one target injectable measurable lesion ≥1 cm in longest diameter that can be followed.

• Any smoking history is permitted. While discouraged, patients are permitted to continue tobacco use while on the study.

• Age 18 years or older at the time of consent.

• Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1 or 2.

• Participant must have normal marrow function and coagulation profile as defined within 21 days prior to study registration:

  • absolute neutrophil count ≥1,000/mcL
  • hemoglobin ≥9 g/dL
  • platelets ≥75,000/mcL, and (d) PT/INR <2.5, and (e) aPTT <1.5x ULN.

• Women of childbearing potential (WOCBP) must agree to use appropriate method(s) of contraception. WOCBP and men should plan to use an adequate method to avoid pregnancy for 90 days after the last dose of RP2. WOCBP 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. Serum or urine BhCG testing is required within 24 hours of initial RP2 dosing.

Exclusion Criteria

• Prior treatment with an oncolytic virus therapy.
• Systemic infection requiring intravenous (IV) antibiotics.
• Requires chronic use of systemic (oral or IV) antivirals with known antiherpetic activity (e.g. acyclovir or valacyclovir).
• Active significant herpetic infections or prior complications of HSV-1 infection (e.g., herpetic keratitis or encephalitis). Patients with sporadic cold sores may be enrolled provided they are asymptomatic at the time of starting RP2.
• Known acute or chronic hepatitis B (defined as hepatitis B surface antigen [HBsAg] reactive) or acute or chronic hepatitis C virus (defined as HCV RNA [qualitative] is detected). Note: Patients who have been effectively treated are eligible for enrollment. Patients must be negative for HBsAg and HCV RNA.
• Known human immunodeficiency virus (HIV) infection. Note: Testing for HIV is not required unless mandated by local health authority or clinically indicated.
• A history of a prior stage III (T1-2N1, T3N0) or IV (T1-3N2, T4N0) invasive head & neck squamous cell carcinoma treated with surgery and/or radiation with or without chemotherapy.
• Patients cannot be on long-term (>4 weeks) corticosteroids at doses exceeding prednisone 20 mg daily (or its equivalent) at the time of enrollment.
• A personal history of hematopoietic stem cell (bone marrow) or solid organ transplant.
• A personal history of other active malignancies, with exceptions including (but not limited to): non-melanomatous skin cancers, low-risk prostate adenocarcinoma on active surveillance, or treated cancers in remission for the last 2 years.
• Significant bleeding event within the last 6 months that places the patient at risk for bleeding due to the injection procedure based on Investigator assessment.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
RP2 Injection	RP2 Injection	Enrolled participants will complete the following: * A 3 subject safety run-in will be conducted with participants enrollment staggered. If \> 1 subject experiences a grade 4-5 adverse event (AE), study enrollment will pause for review by PI and study sponsor. If there are 0 grade 4-5 AEs, enrollment will proceed. * Baseline in-clinic visit with assessments, oral mucosal punch biopsy, and RP2 injection (week 1). * In-clinic visits on weeks 3, 5, 7, 8, 9, 11, 13, 15, and 16. * RP2 injections on weeks 1, 3, 5, 7, 9, 11, 13, and 15. * Repeat oral mucosal punch biopsy at week 8. * Follow up: every 3 months for up to 2 years.

Primary Outcome Measures

Name	Time	Method
Best Overall Response	Up to 1 year	The best overall response is the best response recorded from the start of the treatment until disease progression (taking as reference for progressive disease the smallest measurements recorded since the treatment started). Responses do not require confirmation. Complete response (CR) is complete disappearance of all target lesions. Partial response (PR) is at least 30% decrease in the sum of the diameters of target lesions, taking as reference the baseline sum diameters.

Secondary Outcome Measures

Name	Time	Method
Adverse Event Rate	Up to 1 year	Adverse event rate is defined as the proportion of participants experiencing adverse. Adverse events will be classified and graded according to CTCAE5.0.
Median Cancer-free Survival (CFS)	Up to 1 year	Cancer-Free Survival (CFS) is defined as the time from study registration to development of a biopsy-proven invasive oral cancer (oral squamous cell carcinoma or OSCC) or time to a primary, recurrent, or secondary biopsy-proven invasive head and neck cancer diagnosis (squamous cell carcinoma of the head and neck) or death due to any cause. Participants alive without disease progression or recurrence (of invasive oral cancer) are censored at date of last disease evaluation.
Median Overall Survival (OS)	Up to 3 years	Overall Survival (OS) based on Kaplan-Meier method is defined as the time from registration to death due to any cause, or censored at date last known alive.

Trial Locations

Locations (2)

Brigham and Women's Hospital; 🇺🇸 Boston, Massachusetts, United States

Dana-Farber Cancer Institute; 🇺🇸 Boston, Massachusetts, United States