Acute cell-mediated rejection was defined using the Banff 2007 criteria. Participants with a Banff grade of greater than or equal to 2A were determined to have met the endpoint. Severity is graded as 1A, 1B, 2A, 2B, or 3, with 1A being the mildest form of cellular rejection and 3 being the most severe form of cellular rejection. Antibody mediated rejection was defined as diffusely positive staining for C4d, presence of circulating anti-donor antibodies, and morphologic evidence of acute tissue injury.

Intent-to-treat population who initiated study treatment, subset to participants with available central pathology read data.

Acute cell-mediated rejection was defined using the Banff 2007 criteria. Participants with a Banff grade of greater than or equal to 2A were determined to have met the endpoint. Severity is graded as 1A, 1B, 2IA, 2IB, or 3, with 1A being the mildest form of cellular rejection and 3 being the most severe form of cellular rejection. Antibody mediated rejection was defined as diffusely positive staining for C4d, presence of circulating anti-donor antibodies, and morphologic evidence of acute tissue injury.

Intent-to-treat population who initiated study treatment, subset to participants with available central pathology read data who had severe acute cell-mediated rejection and/or acute antibody mediated rejection. No participants met the criteria for inclusion in this analysis population.

This outcome measure includes infections reported as adverse events. Severe infection was defined in the study as a Grade 3 or higher infection. Severity is graded as 1 through 5, with 1 being least severe to 5 being most severe. Grade 3 is any infection associated with hemodynamic compromise requiring pressors; any infection necessitating ICU level of care; any infection necessitating operative intervention; any infection involving the central nervous system; any infection with a positive fungal blood culture; any proven or probable aspergillus infection; any tissue invasive fungal infection; any pneumocystis jiroveci infection. Grade 4 is any life-threatening infection. Grade 5 is any infection resulting in death.

Intent-to-treat population who initiated study treatment

This outcome measure includes infections reported as adverse events. Severe infection was defined in the study as a Grade 3 or higher infection. Severity is graded as 1 through 5, with 1 being least severe to 5 being most severe. Grade 3 is any infection associated with hemodynamic compromise requiring pressors; any infection necessitating ICU level of care; any infection necessitating operative intervention; any infection involving the central nervous system; any infection with a positive fungal blood culture; any proven or probable aspergillus infection; any tissue invasive fungal infection; any pneumocystis jiroveci infection. Grade 4 is any life-threatening infection. Grade 5 is any infection resulting in death.

Intent-to-treat population who initiated study treatment and experienced a severe infection

The change in inflammation was measured by the percentage area of the renal cortex occupied by inflammatory cells on biopsy 7 months after group allocation. This change was expressed as the percent change relative to the baseline biopsy. The measurements were obtained using computer-assisted quantitative image analysis.

Intent-to-treat population who initiated treatment, subset to participants from the Maintenance and polyTregs groups with available LCA data from the biopsy 7 months post-group allocation. darTregs group excluded from efficacy analysis per the protocol and statistical analysis plan.

CRM (Common Response Module) score is a geometric mean of CRM gene expression. This score is used to identify evidence of rejection or inflammation in participants at the time of biopsy.

Data were not collected for this endpoint.

An infusion reaction is characterized by an adverse reaction to the infusion of pharmacological substance, as defined using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 set forth by the National Cancer Institute.

Intent-to-treat population, subset to participants who received the polyTregs infusion

Severity of infusion reactions were defined using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 set forth by the National Cancer Institute. Severity of adverse events is graded as 1 through 5, with 1 being least severe to 5 being most severe.

Intent-to-treat population, subset to participants who received the polyTregs infusion and had a polyTregs infusion reaction. No participants met the criteria for inclusion in this analysis population.

An infusion reaction is characterized by an adverse reaction to the infusion of pharmacological substance, as defined using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0 set forth by the National Cancer Institute.

Intent-to-treat population, subset to participants who received the polyTregs infusion and had a polyTregs infusion reaction. No participants met the criteria for inclusion in this analysis population.

A culture-proven and clinically diagnosed infection in this study was defined as any locally reported infection due to bacterial organism, due to fungal organism, due to CMV, or which met adverse event criteria, except for COVID-19.

Intent-to-treat population who initiated study treatment

A culture-proven and clinically diagnosed infection was defined as any locally reported infection due to bacterial organism, fungal organism, CMV, or which met adverse event criteria, except for COVID-19. Severe infection was defined in the study as a Grade 3 or higher infection. Severity is graded as 1 through 5 with 1 being least severe to 5 being most severe. Grade 3 is any infection associated with hemodynamic compromise requiring pressors; any infection necessitating ICU level of care; any infection necessitating operative intervention; any infection involving the central nervous system; any infection with a positive fungal blood culture; any proven or probable aspergillus infection; any tissue invasive fungal infection; any pneumocystis jiroveci infection. Grade 4 is any life-threatening infection. Grade 5 is any infection resulting in death. If a culture proven and clinically diagnosed infection did not qualify for AE reporting, then it did not have a severity grade.

Intent-to-treat population who initiated study treatment, subset to those with culture-proven and clinically diagnosed infections

A culture-proven and clinically diagnosed infection in this study was defined as any locally reported infection due to bacterial organism, fungal organism, CMV, or which met adverse event criteria, except for COVID-19.

Intent-to-treat population who initiated study treatment, subset to those with culture-proven and clinically diagnosed infections

Acute cell-mediated rejection was defined using the Banff 2007 criteria. Participants with a Banff grade of greater than or equal to 1A were determined to have met the endpoint. Severity is graded as 1A, 1B, 2A, 2B, or 3, with 1A being the mildest form of cellular rejection and 3 being the most severe form of cellular rejection.

Intent-to-treat population who initiated study treatment, subset to participants with available central pathology read data.

Acute cell-mediated rejection was defined using the Banff 2007 criteria. Participants with a Banff grade of greater than or equal to 1A were determined to have met the endpoint. Severity is graded as 1A, 1B, 2A, 2B, or 3, with 1A being the mildest form of cellular rejection and 3 being the most severe form of cellular rejection.

Intent-to-treat population who initiated study treatment, subset to participants with available central pathology read data and who experienced acute rejection. No participants met the criteria for inclusion in this analysis population.

Acute cell-mediated rejection was defined using the Banff 2007 criteria. Participants with a Banff grade of greater than or equal to 1A were determined to have met the endpoint. Severity is graded as 1A, 1B, 2A, 2B, or 3, with 1A being the mildest form of cellular rejection and 3 being the most severe form of cellular rejection.

Intent-to-treat population who initiated study treatment, subset to participants with available central pathology read data and who experienced acute rejection. No participants met the criteria for inclusion in this analysis population.

BK viremia was determined using locally reported serum PCR results. PCR results reported as positive and >0 copies/mL were considered as meeting the endpoint. Only positive results following Treg infusion were considered for participants in the polyTregs and darTregs groups.

Intent-to-treat population who initiated study treatment

BK viremia was determined using locally reported serum PCR results. PCR results reported as positive and >0 copies/mL were considered as meeting the endpoint. Only positive results following Treg infusion were considered for participants in the polyTregs and darTregs groups.

Intent-to-treat population who initiated treatment, subset to participants who experienced BK viremia.

CMV reactivation was defined as CMV viremia and determined using locally reported serum, plasma, or whole blood PCR results. PCR results reported as >0 IU/mL were considered as meeting the endpoint. Only positive results following Treg infusion were considered for participants in the polyTregs and darTregs groups.

Intent-to-treat population who initiated treatment

CMV reactivation was defined as CMV viremia and determined using locally reported serum, plasma, or whole blood PCR results. PCR results reported as >0 IU/mL were considered as meeting the endpoint. Only positive results following Treg infusion were considered for participants in the polyTregs and darTregs groups.

Intent-to-treat population who initiated treatment, subset to participants who experienced CMV reactivation.

Glomerular filtration rate (GFR) is a measure of kidney function and helps determine the stage of kidney disease. eGFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI) 2021 equation. A value of 90+ means kidney function is normal. A value between 60 and 89 indicates mildly reduced kidney function, pointing to kidney disease. Values between 30 and 59 indicate moderately reduced kidney function. Values between 15 and 29 indicate severely reduced kidney function. Values below 15 indicate very severe or end stage kidney failure. The percent change in eGFR was calculated at each post-baseline timepoint as [(post-baseline eGFR minus baseline (i.e., screening) eGFR) divided by baseline eGFR] multiplied by 100 and rounded to the nearest hundredth for each participant. A participant was considered to have met the endpoint if at least one instance of a greater than 10% decrease from baseline was observed.

Intent-to-treat population who initiated treatment

Glomerular filtration rate (GFR) is a measure of kidney function and helps determine the stage of kidney disease. eGFR was estimated using the Chronic Kidney Disease Epidemiology Collaboration equation (CKD-EPI) 2021 equation. A value of 90+ means kidney function is normal. A value between 60 and 89 indicates mildly reduced kidney function, pointing to kidney disease. Values between 30 and 59 indicate moderately reduced kidney function. Values between 15 and 29 indicate severely reduced kidney function. Values below 15 indicate very severe or end stage kidney failure. The percent change in eGFR was calculated at each post-baseline timepoint as [(post-baseline eGFR minus baseline (i.e., screening) eGFR) divided by baseline eGFR] multiplied by 100 and rounded to the nearest hundredth for each participant. A participant was considered to have met the endpoint if at least one instance of a greater than 10% decrease from baseline was observed.

Intent-to-treat population who initiated treatment, subset to participants who had a >10% decrease in eGFR.

Acute cell-mediated rejection was defined using the Banff 2007 criteria. Participants with a Banff grade of greater than or equal to 2A were determined to have met the endpoint. Severity is graded as 1A, 1B, 2A, 2B, or 3, with 1A being the mildest form of cellular rejection and 3 being the most severe form of cellular rejection.

Intent-to-treat population who initiated treatment, subset to participants who received the polyTregs infusion and converted to mTOR therapy. No participants met the criteria for inclusion in this analysis population.

Acute cell-mediated rejection was defined using the Banff 2007 criteria. Participants with a Banff grade of greater than or equal to 2A were determined to have met the endpoint. Severity is graded as 1A, 1B, 2A, 2B, or 3, with 1A being the mildest form of cellular rejection and 3 being the most severe form of cellular rejection.

Intent-to-treat population who initiated treatment, subset to participants who received the polyTregs infusion, converted to mTOR therapy, and had an acute rejection event. No participants met the criteria for inclusion in this analysis population.

The change in inflammation was measured by the percentage area of the renal cortex occupied by inflammatory cells on biopsy 2 weeks after polyTregs infusion. This change was expressed as the percent change relative to the baseline biopsy. The measurements were obtained using computer-assisted quantitative image analysis.

Intent-to-treat population who initiated treatment, subset to participants with available LCA data from the Week 2 biopsy

The change in inflammation was measured by the percentage area of the renal cortex occupied by inflammatory cells on biopsy 2 weeks after polyTregs infusion. This change was expressed as the percent change relative to the baseline biopsy. The measurements were obtained using computer-assisted quantitative image analysis.

Intent-to-treat population who initiated treatment, subset to participants with available LCA data from the Week 2 biopsy

The change in inflammation was measured by the percentage area of the renal cortex occupied by inflammatory cells on biopsy 7 months after study group allocation. This change was expressed as the percent change relative to the baseline biopsy. The measurements were obtained using computer-assisted quantitative image analysis.

Intent-to-treat population who initiated treatment, subset to participants with available LCA data from the biopsy 7 months post-group allocation