Study of the Tolerability and Pharmacokinetics of Oral Doses of SAR442168 With a Food Effect Investigation in Healthy Adult Participants

This is a randomized, placebo-controlled, four-part, Phase I, first in human (FIH) study to assess the tolerability and pharmacokinetics (PK) of ascending single and 14-day repeated oral doses of SAR442168 with a food effect investigation in healthy adult participants. * In Part 1a: The tolerability and safety of SAR442168 and the pharmacokinetic parameters of SAR442168 and metabolite(s)after ascending single oral doses in fasted and fed conditions * In Part 1b: The relationship of PK of SAR442168 and metabolite(s) in cerebrospinal fluid (CSF) to that in plasma after single oral doses given in fed conditions (moderate-fat meal) * In Part 1c: The effect of a high-fat meal on the pharmacokinetics of SAR442168 and metabolite(s) (high-fat) * In Part 1d: The effect of a high-fat meal on the pharmacokinetics of SAR442168 and metabolite(s) (standardized high-fat meal) * In Part 2: The tolerability and safety of SAR442168 and the pharmacokinetic parameters of SAR442168 and metabolite(s) after 14-day ascending repeated oral doses of SAR442168 given in fed conditions (moderate-fat meal).