DLT: greater than or equal to (>=) Grade 3 hematologic/non-hematologic toxicity, Grade 3-4 liver-related laboratory test elevation (alanine aminotransferase, aspartate aminotransferase) with Grade 2 elevation of total bilirubin, non-hematologic Grade 3 laboratory abnormality (required medical intervention to treat participant/led to hospitalization), inability to complete >=75% of first 2 cycles doses of axitinib (from Cycle 1 Day 1 after completion of lead-in period) or 2 infusions of avelumab within DLT observation period due to investigational product related toxicity.

DLT evaluable analysis set: First 6 enrolled participants who received at least 1 dose of avelumab and axitinib, and either experienced DLT during DLT observation period or completed it. Data for this endpoint was only planned to be collected and analyzed for "Axitinib + Avelumab with Lead-in" arm.

Adverse event (AE)=any untoward medical occurrence in participant who received study treatment without regard to causality. TEAE=event between first dose of study treatment and up to 30 days after last dose that were absent before treatment or worsened relative to pretreatment state. Serious AE (SAE)=AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience; persistent or significant disability/incapacity; congenital anomaly. AEs were graded by worst National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) v4.03 severity grade. Grade 3 event=unacceptable or intolerable event, significantly interrupting usual daily activity, require systemic drug therapy/other treatment. Grade 4 event caused participant to be in imminent danger of death. Grade 5 event=death related to AE. The results reflect data available on cutoff of LPLV (04 Mar 2021).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib.

Treatment-related AE was any untoward medical occurrence attributed to study drug in a participant who received study drug. TEAE=event between first dose of study treatment and up to 30 days after last dose that were absent before treatment or that worsened relative to pretreatment state. An SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience; persistent or significant disability/incapacity; congenital anomaly. AEs were graded by worst NCI CTCAE v4.03 severity grade. Grade 3 events=unacceptable or intolerable events, significantly interrupting usual daily activity, require systemic drug therapy/other treatment. Grade 4 events caused participant to be in imminent danger of death. Grade 5 events=death related to an AE. Treatment-related AEs and SAEs were determined by the investigator. The results reflect data available on cutoff of LPLV (04 Mar 2021).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib.

Laboratory abnormalities (hematology) reported included anemia, platelet count decreased, lymphocyte count decreased, and neutrophil count decreased. Grade 1=mild transient reaction; infusion interruption not indicated; intervention not indicated. Grade 2=therapy or infusion interruption indicated but responds promptly to symptomatic treatment; prophylactic medications indicated for <=24 hours. Grade 3=prolonged; recurrence of symptoms following initial improvement; hospitalization indicated for clinical sequelae. Grade 4=life threatening consequences; urgent intervention indicated. Grade 5=death. The results reflect data available on cutoff of LPLV (04 Mar 2021).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib.

Laboratory abnormalities (chemistry) reported included creatinine increased, serum amylase increased, lipase increased, alanine aminotransferase (ALT) increased, aspartate aminotransferase (AST) increased, blood bilirubin increased, creatine kinase increased, hypoglycemia, and hyperglycemia. Grade 1=mild transient reaction; infusion interruption not indicated; intervention not indicated. Grade 2=therapy or infusion interruption indicated but responds promptly to symptomatic treatment; prophylactic medications indicated for <=24 hours. Grade 3=prolonged; recurrence of symptoms following initial improvement; hospitalization indicated for clinical sequelae. Grade 4=life threatening consequences; urgent intervention indicated. Grade 5=death. The results reflect data available on cutoff of LPLV (04 Mar 2021).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib.

Blood pressure was taken with the participant in the seated position after the participant had been sitting quietly for at least 5 minutes. Baseline was defined as the last assessment prior to the date/time of the first dose of study treatment, which occurred on Day 1 in Lead-in period for participants with lead-in, and occurred on Cycle 1 Day 1 (C1D1) for participants without lead-in. The results reflect data available on cutoff of primary completion date (PCD) (03 Apr 2018).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib (ie, safety analysis set). Number of Participants Analyzed represents the total number of participants in the safety analysis set. Number Analyzed in each row represents the number of participants in the safety analysis set with at least 1 baseline and 1 post-baseline assessments at the visit.

Blood pressure was taken with the participant in the seated position after the participant had been sitting quietly for at least 5 minutes. Baseline was defined as the last assessment prior to the date/time of the first dose of study treatment, which occurred on Day 1 in Lead-in period for participants with lead-in, and occurred on Cycle 1 Day 1 (C1D1) for participants without lead-in. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib (ie, safety analysis set). Number of Participants Analyzed represents the total number of participants in the safety analysis set. Number Analyzed in each row represents the number of participants in the safety analysis set with at least 1 baseline and 1 post-baseline assessments at the visit.

Pulse rate was taken with the participant in the seated position after the participant had been sitting quietly for at least 5 minutes. Baseline was defined as the last assessment prior to the date/time of the first dose of study treatment, which occurred on Day 1 in Lead-in period for participants with lead-in, and occurred on Cycle 1 Day 1 (C1D1) for participants without lead-in. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib (ie, safety analysis set). Number of Participants Analyzed represents the total number of participants in the safety analysis set. Number Analyzed in each row represents the number of participants in the safety analysis set with at least 1 baseline and 1 post-baseline assessments at the visit.

Confirmed OR was defined as complete response (CR) or partial response (PR) according to RECIST v1.1 from the start date until disease progression or death due to any cause. CR was defined as complete disappearance of all target lesions with the exception of nodal disease. All target nodes must decrease to normal size (short axis <10 mm). PR was defined as >= 30% decrease under baseline of the sum of diameters of all target measurable lesions. The short diameter was used in the sum for target nodes, while the longest diameter was used in the sum for all other target lesions. All target lesions must have been assessed. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all participants who received at least 1 dose of study drug (axitinib or avelumab) and all participants who were randomized independent of whether they had received a dose of study drug.

DC was defined as OR (CR or PR) or stable disease (SD) per RECIST v1.1 from the start date until the first documentation of objective disease progression or death due to any cause. SD was defined as not qualifying for CR, PR, or progression (PD). PD was defined as 20% increase in the sum of diameters of target measurable lesions above the smallest sum observed (over baseline if no decrease in the sum was observed during therapy), with a minimum absolute increase of 5 mm. CR was defined as complete disappearance of all target lesions with the exception of nodal disease. All target nodes must decrease to normal size (short axis <10 mm). PR was defined as >= 30% decrease under baseline of the sum of diameters of all target measurable lesions. The short diameter was used in the sum for target nodes, while the longest diameter was used in the sum for all other target lesions. All target lesions must have been assessed. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all participants who received at least 1 dose of study drug (axitinib or avelumab) and all participants who were randomized independent of whether they had received a dose of study drug.

DR was defined as the time from the first documentation of objective tumor response (CR or PR) that was subsequently confirmed to the first documentation of objective tumor progression or to death due to any cause, whichever occurred first. CR was defined as complete disappearance of all target lesions with the exception of nodal disease. All target nodes must decrease to normal size (short axis <10 mm). PR was defined as >= 30% decrease under baseline of the sum of diameters of all target measurable lesions. The short diameter was used in the sum for target nodes, while the longest diameter was used in the sum for all other target lesions. All target lesions must have been assessed. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all participants who received at least 1 dose of study drug (axitinib or avelumab), all participants who were randomized independent of whether they had received a dose of study drug, and all participants who had achieved confirmed CR or PR.

PFS was defined as defined as the time from the start date to the date of the first documentation of objective progression of disease (PD) or death due to any cause, whichever occurred first. PD was defined as 20% increase in the sum of diameters of target measurable lesions above the smallest sum observed (over baseline if no decrease in the sum was observed during therapy), with a minimum absolute increase of 5 mm. All target lesions must have been assessed. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all participants who received at least 1 dose of study drug (axitinib or avelumab) and all participants who were randomized independent of whether they had received a dose of study drug.

TTR was defined as the time from start date to the first documentation of objective tumor response (CR or PR) that was subsequently confirmed. CR was defined as complete disappearance of all target lesions with the exception of nodal disease. All target nodes must decrease to normal size (short axis <10 mm). PR was defined as >= 30% decrease under baseline of the sum of diameters of all target measurable lesions. The short diameter was used in the sum for target nodes, while the longest diameter was used in the sum for all other target lesions. All target lesions must have been assessed. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all participants who received at least 1 dose of study drug (axitinib or avelumab), all participants who were randomized independent of whether they had received a dose of study drug, and all participants who had achieved confirmed CR or PR.

OS was defined as the time from the start date to the date of death due to any cause. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all participants who received at least 1 dose of study drug (axitinib or avelumab) and all participants who were randomized independent of whether they had received a dose of study drug.

Cmax for axitinib when dosed alone on Lead-in Day 7 and in combination with avelumab on Cycle 4 Day 1 for Axitinib + Avelumab with Lead-in Arm. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib and who had at least 1 of the pharmacokinetic (PK) parameters of interest of either study drug.

Tmax for axitinib when dosed alone on Lead-in Day 7 and in combination with avelumab on Cycle 4 Day 1 for Axitinib + Avelumab with Lead-in Arm. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib and who had at least 1 of the pharmacokinetic (PK) parameters of interest of either study drug.

AUCtau was defined as area under the plasma concentration time profile from time zero to time tau, the dosing interval at steady state. tau = 12 hrs for Axitinib. AUCtau for Axitinib when dosed alone on Lead-in Day 7 and in combination with avelumab on Cycle 4 Day 1 for Axitinib + Avelumab with Lead-in Arm was reported. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib and who had at least 1 of the pharmacokinetic (PK) parameters of interest of either study drug.

t1/2 was calculated by Log e(2)/kel. kel was the terminal phase rate constant calculated by a linear regression of the log linear concentration time-curve. Only those data points judged to describe the terminal log linear decline were used in the regression. t1/2 for Axitinib when dosed alone on Lead-in Day 7 and in combination with avelumab on Cycle 4 Day 1 for Axitinib + Avelumab with Lead-in Arm was reported. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib and who had at least 1 of the pharmacokinetic (PK) parameters of interest of either study drug.

Ctrough was directly observed from data. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib and who had at least 1 of the pharmacokinetic (PK) parameters of interest of either study drug.

Cmax for avelumab on Cycle 1 Day (C1D1) and C1D4 were reported. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all enrolled participants who received at least 1 dose of avelumab or axitinib and who had at least 1 of the pharmacokinetic (PK) parameters of interest of either study drug.

Number of participants with PD-L1 positive (PD-L1 >=1%) status in immune cell (IC), tumor cell (TC), or both IC and TC. The results reflect data available on cutoff of PCD (03 Apr 2018).

The population for this outcome measure included all enrolled participants who had at least 1 screening biomarker assessment and who received at least 1 dose of avelumab or axitinib.

Whole blood specimens were collected at the designated times (Day 1 of Cycles 1-4, 6, and 8, then every 12 weeks until Cycle 50, and Follow-up Day 30) to provide serum for evaluation of avelumab immunogenicity. Human serum ADA specimens were analyzed for the presence or absence of anti-avelumab antibodies with quasi-quantitative enzyme-linked immunosorbent assay, following a tiered approach using screening, confirmation and titer/quantitation. ADA serum specimens were screened at tier 1. In the event that there were no positive specimens, no further analyses were to be conducted. If positive specimens were identified, these specimens were further tested with the confirmatory assay to confirm as positive. Number of participants with ADA positive at baseline, ADA never-positive, ADA ever-positive, treatment-boosted ADA, treatment-induced ADA, transient ADA response, or persistent ADA response from baseline up to 2 years. The results reflect data available on cutoff of PCD (03 Apr 2018).

The analysis population (ie, Number of Participants Analyzed)=number of participants (#p) received at least 1 dose of study drug and with at least 1 ADA sample collected. Number Analyzed =Number of Participants Analyzed for ADA_p and ADA_n; = #p with valid baseline ADA result for ADA_bp; = #p with valid baseline and at least 1 valid post-baseline ADA results for Tb_ADA; = #p with at least 1 valid post-baseline ADA result and without positive baseline ADA result for Ti_ADA, t_ADA, and p_ADA.