NL-201 Monotherapy and in Combination With Pembrolizumab in Patients With Relapsed or Refractory Cancer

Inclusion Criteria:

* Patients with measurable disease
* Patients with Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
* At least 6 weeks from any prior nitrosurea or mitomycin C therapy; at least 4 weeks from any other prior chemotherapy or checkpoint inhibitor; at least 2 weeks from any kinase inhibitor
* Part 1 Only: Patients with relapsed or refractory advanced solid tumor, other than prostate cancer, who have progressed, not tolerated or are ineligible for all approved lines of therapy
* Part 2 Only: Patients with kidney and skin cancer who have failed at least 1 line of systemic therapy
* Part 3 Only: Patients with solid tumors who have received ≥ 1 prior line of therapy for advanced or metastatic disease
* Part 4 Only: Patients with diagnosed target disease OR previously received pembrolizumab

Exclusion Criteria:

* Prostate Cancer
* Any serious medical condition or laboratory abnormality or psychiatric condition or any other significant or unstable concurrent medical illness (in the opinion of the Investigator) would preclude protocol adherence or would make the safety of the study drug difficult to assess
* Known or suspected SARS-CoV-2 infection, unless patient tests negative for SARS-CoV-2 within the Screening period
* History of solid organ transplant or bone marrow transplant
* Prior chimeric antigen receptor T-cell (CAR-T) or allogeneic cellular therapy
* Prior IL-2-based cancer therapy
* Ongoing systemic immunosuppressive therapy
* Concurrent therapy with any other investigational agent, vaccine, or device.
* Part 3 and 4 Only: History of (non-infectious) pneumonitis/interstitial lung disease that required steroids or has current pneumonitis/interstitial lung disease
* Part 3 and 4 Only: Known additional cancer that is progressing or has required active treatment within the past 2 years. Note: Participants with basal cell carcinoma of the skin, squamous cell carcinoma of the skin, or carcinoma in situ (eg, breast carcinoma, cervical cancer in situ) that have undergone curative resection are eligible.