A Rollover Study for Subjects Who Completed Participation in IMSA101-101 Trial

Rollover Study to Continue IMSA101 Treatments in Patients With Advanced Treatment-Refractory Malignancies Previously Enrolled in the Phase I/IIA Safety and Efficacy Study of IMSA101

This is a rollover study from parent protocol IMSA101-101 for adult patients with advanced malignancies that were previously receiving IMSA101 and who would continue to receive benefit with study treatment of IMSA101 in combination with an immune checkpoint inhibitor (ICI).

The following methodology applies to all patients:

• Treatment cycles will be 28 days in duration with lesions injected every 2 weeks. IMSA101 dose level will remain the same as at the time of the rollover from parent protocol.
• ICI dose level and treatment regimen will remain the same as at the time of the rollover from parent protocol, following the labeled instructions.
• The same single pre-defined lesion/lesion site (longest diameter ≥ 10 mm and ≤ 50 mm) shall be injected throughout study duration, if possible. Where the original injection site is considered by the investigator to become inaccessible, a second lesion/lesion site shall be selected as a replacement and this shall be used henceforth so long as it is considered accessible. Subsequent injection sites shall be replaced when they are considered inaccessible.
• Where no remaining accessible lesions are present and where benefit of IMSA101 therapy is, in the opinion of the investigator, being derived by the patient, continued injections of IMSA101 into the vicinity of an inaccessible lesion or, in the case that a lesion can no longer be radiographically visualized, into the last known location of the non-visible lesion shall be allowed.

Inclusion Criteria:

1. Signed informed consent and mental capability to understand the informed consent
2. Currently enrolled in parent protocol IMSA101-101 and is receiving IMSA101 treatment
3. Deriving clinical benefit from study treatment, as determined by the investigator
4. Must have fulfilled all required assessments in parent protocol IMSA101-101
5. Male and female patients with reproductive potential must agree to use two forms of highly effective contraception throughout the study

Exclusion Criteria:

1. Permanently discontinued from IMSA101 treatment in parent protocol IMSA101-101 for any reason other than enrollment in the rollover study
2. Failure to meet the criteria specified in parent protocol IMSA101-101 for continued study treatment