Sasanlimab (PF-06801591, PD-1 Inhibitor) in Participants With Advanced Malignancies

- Age ≥18 years (≥ 20 years in Japan; ≥ 19 years in South Korea)

- Easter Cooperative Oncology Group (ECOG) performance status 0 or 1

- Adequate bone marrow function, renal and liver functions Phase 1b

- Histological or Cytological diagnosis of advanced solid tumor with clinical evidence of response to anti-PD-1 or PD-L1 agent

- Participant must have received at least 1 prior line of therapy for recurrent or metastatic disease, and must have progressed/relapsed, be refractory, or intolerant to standard therapy approved for the specific tumor type Phase 2

- Participants must have a documented diagnosis of stage III where participants are not candidates for surgical resection or definitive chemoradiation, or stage IV NSCLC

- EGFR mutation, BRAF mutation, and ALK or ROS1 translocation/rearrangement are not permitted

- Participants whose tumor is known to be PD-L1 positive (Tumor Proportion Score [TPS] ≥1%) or unknown are eligible

- Up to 1 line of prior therapy in advanced or metastatic disease settings allowed

- Participant should not have received prior treatment with anti PD-1/PD-L1 drugs

- At least one measurable lesion as defined by RECIST version 1.1

- Participants with known symptomatic brain metastases requiring steroids

- Participants with Interstitial Lung Disease history or complication

- Q-T interval corrected for heart rate QTc > 450 msec for male participants or QTc > 470 msec for female participants or QTc > 480 msec in participants with right bundle branch block.

- Hypertension that cannot be controlled by medications (eg, systolic > 150 mmHg and diastolic > 90 mmHg) despite optimal medical therapy.

- Known or suspected hypersensitivity to active ingredient or excipients of the study drug.

- History of Grade ≥3 immune mediated AE (including AST/ ALT elevations that where considered drug related and cytokine release syndrome [CRS]) that was considered related to prior immune modulatory therapy (eg, immune checkpoint inhibitors, co-stimulatory agents, etc.) and required immunosuppressive therapy (For Phase 1b only).

- Vaccination with live attenuated vaccines within 4 weeks prior to randomization is prohibited; however inactivated vaccines are permitted.