The study was withdrawn due to insufficient interest in study participation due to recent approval in this rare condition.

The purpose of this study is to assess the safety and tolerability of parsaclisib in participants with mild to moderate pemphigus vulgaris.

Inclusion Criteria:

• Clinically documented and confirmed diagnosis of pemphigus vulgaris: minimum of 6 months of pemphigus vulgaris diagnosis; positive for anti-desmoglein (DSG)1 or DSG3; Pemphigus Disease Area Index score of 8 to 45 points; active skin, scalp, or mucosal lesions.
• Disease progression after treatment with standard therapies that are known to confer clinical benefit, or intolerant to treatment; there is no limit to the number of prior treatment regimens.
• Willingness to avoid pregnancy or fathering children.
• If required, willing to receive Pneumocystis jirovecii pneumonia prophylaxis during the study period.

Exclusion Criteria:

• Pregnant or breast-feeding female.
• Participants with pemphigus vulgaris who are treatment-naive.
• Use of protocol-specified medications within defined periods before baseline.
• Evidence or history of clinically significant infection or protocol-defined medical conditions
• Laboratory values outside the protocol-defined range at screening.
• Known or suspected allergy to parsaclisib or any component of the study drug.
• Known history of clinically significant drug or alcohol abuse in the last year before baseline.
• Inability or unlikeliness of the participant to comply with the dose schedule and study evaluations, in the opinion of the investigator.
• Any condition that would, in the investigator's judgment, interfere with full participation in the study, including administration of study drug and attending required study visits; pose a significant risk to the participant; or interfere with interpretation of study data.