- Participants with detectable DSA and a positive flow cytometric crossmatch may undergo de-sensitization per standard of care if they are cytotoxic crossmatch negative. Such participants must demonstrate a negative flow cytometric crossmatch by day -9 in order to receive the first dose of study therapy (ATG). Participants who do not demonstrate an acceptable response to de-sensitization by day -9 will be considered screen failures and will be terminated from the study.