An Open-Label, Multicenter, Phase 1 Study of RP3 as a Single Agent and in Combination with PD-1 Blockade in Patients with Solid Tumors

Inclusion Criteria:

• Patients with advanced or metastatic non-neurological solid tumors, who have progressed on standard therapy or cannot tolerate standard therapy, or for whom there is no standard therapy preferred to enrollment in a clinical study
• All patients must consent to provide archival tumor biopsy samples within 12 months, or a fresh tumor biopsy is needed. Patients must also consent to provide on treatment biopsies as per protocol
• At least one measurable tumor ≥ 1 cm in longest diameter (or shortest diameter for lymph nodes)
• At least one injectable tumor ≥ 1 cm in longest diameter or injectable tumors which in aggregate are ≥ 1 cm in longest diameter (or shortest diameter for lymph nodes
• Have an Eastern Cooperative Oncology Group (ECOG) performance status 0-1

Note: Predefined inclusion criteria may apply for each additional expansion cohort.

Exclusion Criteria:

• Prior treatment with an oncolytic virus therapy
• History of viral infections according to the protocol
• Systemic infection requiring intravenous (IV) antibiotics
• Active significant herpetic infections or prior complications of HSV-1 infection (e.g., herpetic keratitis or encephalitis)

• Requires intermittent or chronic use of systemic antivirals

  a. Hepatocellular carcinoma patients with a diagnosis of hepatitis B must be off antiviral therapy for at least 4 weeks prior to enrollment . Hepatocellular carcinoma patients with a history of or ongoing hepatitis C infection must have completed treatment for hepatitis C at least 1 month prior to study enrollment and hepatitis

• History of interstitial lung disease
• Has a history of (non-infectious) pneumonitis that required steroids or has current pneumonitis

Additional Exclusion Criteria for Patients Enrolled in Part 2 (Expansion Cohorts):

• History of life-threatening toxicity related to prior immune treatment or any other antibody or drug specifically targeting T-cell co-stimulation or immune checkpoint pathways
• Treatment with botanical preparations within 2 weeks prior to treatment.
• Active, known, or suspected autoimmune disease requiring systemic treatment.
• History of interstitial lung disease.
• Severe hypersensitivity to another monoclonal antibody.
• Has received prior radiotherapy within 2 weeks of start of study treatment.
• Has received a live vaccine within 28 days prior to the first dose of study treatment.
• History of (non-infectious) pneumonitis that required steroids or has current pneumonitis.
• History of myocarditis or congestive heart failure within 6 months of screening.
• Has a serious or uncontrolled medical disorder.
• Has a QT interval corrected for heart rate using Fridericia's formula (QTcF) > 480 msec, except for right bundle branch block.