22. Investigational Product Administration: Treatment to be administered after all other assessments required on that day have been performed. 23. Tumor Assessments: Tumor assessments will include all known or suspected disease sites. Screening images may be obtained within 5 weeks of regist ration. Imaging obtained as part of standard of care but within 28 days (-7 days) of registration may be used for screening assessment. Imagin g may include chest, abdomen and pelvis CT or MRI scans, and bone scans. Bone scans will be performed at baseline if disease is suspected and on study as appropriate to foll ow disease. Baseline central nervous system (CNS) imaging MRI or CT Brain to be conducted only if clinically indicated based on the investigator’s judgement. CT or MRI sc ans, as well as bone scans, when indicated, are to be done every 8 weeks ( ±5 days) with the first one to occur 8 weeks after C1D1 Repeat imaging will be completed every 8 weeks up to and including Month 8 (Week 32) or until disease progression that requires new treatment modality, permanent discontinuation, or death. Disease progression will be confirmed with 2 consecutive timepoints at least 4-8 weeks apart in the absence of rapid clinical deterioration. Tumor assessment should be repeated at the End of Treatment visit if more than 6 weeks have passed since the last evaluation. 25. Acetylcholine receptor (AChR) antibody: Sample to be sent to the central laboratory for analysis. The evaluation for AChR antibodies is included to exclude participants who te st positive at screening as agreed upon with the United States Food and Drug Administration (US FDA) and to confirm requirement for evaluation if myasthenia gravis is suspected .99 30. Serious and Non-serious Adverse Event Monitoring : Adverse events should be documented and recorded at each visit using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTC AE) version 5.0. Participants must be followed for AEs for 6 months after the last study treatment administration or until all drug related toxicities have resolved, whichever is later; or earlier than 6 months should the participant commence another anticancer therapy in the meantime. The time period for actively eliciting and collecting AEs and SAEs (“active collection period”) for each participant begins from the tim e the participant provides informed consent through and including 6 months after the last study treatment administration or until all drug related toxicities have resolved, whichever is later. If the participant begins a CCI CCI CCI PF-06936308 C3621001Final Protocol Amendment 2, 22 Dec 2020 PFIZER CONFIDENTIAL Page 33Protocol Activity Screen 1 (≤28 days)Treatment Period Post Treatment Cycle 1 Cycle 2 End of Treatment 32Follow- Up (Months after EOT visit)Survival Follow-up34 Study Day Day 1Day 8Day 15Day 22Day 29Day 43Day 57Day 71Day 85Day 113Month 133Month 2 Month 4 Month 6 Post 6-Month Follow-up Cycle Day Day 1Day 29Day 57Day 85Day 9928 to 35 daysEvery 3 Months Visit Window (Days) *±1±2 ±2 ±2 ±4 ±2 ±4 ±2 ±2 ±2 ±2 ±2 ±4 ±4 ±4 ±4 ±10 new anticancer therapy, the period for recording non-serious AEs on the CRF ends at the time the new treatment is started. How ever, any SAEs occurring during the active collection period must still be reported to Pfizer Safety and recorded on the CRF, irrespective of any intervening treatment. 31. Concomitant Treatments : All concomitant medications and non-drug supportive interventions should be recorded in the CRF. 32. End of Treatment Visit : The End of treatment visit will be completed at the time point when a decision is made to discontinue study treatment. This c an occur during Cycles 1 or 2 or during the Maintenance Treatment Phase of the study. Obtain these assessments if not completed in the past 2 weeks (past 6 weeks for tumor assessments). 33. Follow up : At least 28 days, and no more than 35 days after discontinuation of study treatment, participants will return to complete the re quired assessments. Participants will then return at Month 2, Month 4 and Month 6 to complete the required assessments. 34. Survival: After treatment discontinuation, participant survival status will be collected every 3 months until death, participant refusal, or lost to follow-up (telephone contact acceptable). CCI PF-06936308 C3621001Final Protocol Amendment 2, 22 Dec 2020 PFIZER CONFIDENTIAL Page 34SCHEDULE OF ACTIVITIES FOR MAINTENANCE TREATMENT PERIOD FOR DOSE EXPANSION (PART 2) Protocol Activity Maintenance Treatment Period * Study Month ** Month 9 Month 10Month 11Month 12Month 13Month 14Month 15Month 16Month 17Month 18 Month 19Month 20Month 21Month 22 and every month thereafter Visit Window (Days) ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 Abbreviated physical examination1XXXXXX X1 W e i g h t XXXXXXXXXXXXX X1 Vital signs2XXXXXXXXXXXXX X1 Performance status3XXXXXXXXXXXXX X1 Laboratory Hematolog y4XXXXXX X1 Blood Chemistr y5XXXXXX X1 Coagulation6XXX X11 Cardiac Troponin-I (cTnI)7XX Urinalysis8XXX X11 Pregnancy Test or FSH Level (Serum)9XXXXXXXXXXXXX X Contraception Check10XXXXXXXXXXXXX X (12 lead) ECG12XX X * Study Treatment pDNA Administration13XXXXXX X1 Tremelimumab administration13XXXXXX X1 Sasanlimab administration13XXXXXXXXXXXXX X Tumor Assessment CT scan, MRI scan or bone scan 14X14 Other Samplings PK and Tremelimumab ADA Refer to Part 2 Schedule of Study Treatment, Pharmacokinetics and Immunogenicity Assessments PK and Sasanlimab ADA Other clinical assessments Serious and non-serious adverse event monitoring18XXXXXXXXXXXXX XCCI PF-06936308 C3621001 Final Protocol Amendment 2, 22 Dec 2020 PFIZER CONFIDENTIAL Page 35Protocol Activity Maintenance Treat ment Period * Study Month ** Month 9 Month 10Month 11Month 12Month 13Month 14Month 15Month 16Month 17Month 18 Month 19Month 20Month 21Month 22 and every month thereafter Visit Window (Days) ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 ±7 Concomitant medications and non-drug supportive interventions19X X X X X X X X X X X X X X Abbreviations: →= ongoing; ADA = anti -drug antibodies; AdC68= Adenovirus; AE = adverse events; CT = computed tomography; ECG = electrocardiogram ;EOT = End of Treatment; MRI = magnetic resonance imaging; PBMC = peripheral blood mononuclear cell; pDNA= plasmid deoxyribonucleic acid; SC = Subcutaneous(ly) * When a decision is made to discontinue study treatment during the Maintenance Treat ment Period, the End of Treat ment visit assess ments should be performed. The participant wil l then enter the Post Treatment Period of the study. ** Study visit is based on completion of 2 cycles in the treatment period. Visit window for the first maintenance treatment visit is to be calculated based on the Cycle 2 Day 85 dosing date. The first dose in the maintenance period should occur 28 days after the C2D85 dosing date. A month is defined as 28 days.