This is a single-dose and multiple doses study to assess the Pharmacokinetics (PK) of rilzabrutinib as well as to evaluate the tolerability of rilzabrutinib in Japanese and Caucasian Healthy Male and Female subjects.

Inclusion Criteria:

• Japanese subjects must have both biological parents and all four grandparents of Japanese ancestry and born in a Japanese country of origin.
• Caucasian subjects must have four Caucasian grandparents (Hispanics of white race can be considered Caucasian).
• Healthy adult male or non-pregnant non-lactating females, 18 to 75 years of age (inclusive) at the time of screening.
• Body mass index (BMI) ≥18 and ≤35 (kg/m2), inclusive, and a minimum body weight of 45 kg.

Additional inclusion criteria might apply.

Exclusion Criteria:

• Symptoms consistent with COVID-19 such as fever, cough, and shortness of breath within 14 days before Day 1.
• Positive test for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at screening or check-in (Day -1).
• Known previous COVID-19 infection.
• Use of any prescription or over-the-counter (OTC) medication, herbal products, or dietary supplements within the 7 days or 5 half-lives, whichever is longer, prior to the first study drug administration. Use of hormonal contraception is allowed prior to and during the study.

Additional exclusion criteria might apply.

Qualified researchers may request access to patient level data and related study documents including the clinical study report, study protocol with any amendments, blank case report form, statistical analysis plan, and dataset specifications. Patient level data will be anonymized and study documents will be redacted to protect the privacy of trial participants. Further details on Sanofi's data sharing criteria, eligible studies, and process for requesting access can be found at: https://vivli.org