A Trial to Learn if ALN-PNP is Safe and Well Tolerated in Adult Healthy Participants

The primary objective of the study is to evaluate the safety and tolerability of single doses of ALN-PNP in healthy adult participants.The secondary objectives of the study are to:Characterize single dose pharmacokinetics (PK) of ALN-PNP and potential major metabolite(s) in adult participantsAssess the immunogenicity of ALN-PNP following single dose administrationsExplore the effects of ALN-PNP on circulating blood lipid profile

Key Inclusion Criteria:For Japanese cohorts ONLY; the Japanese participant must:Be Japanese, born in Japan, and have both biologic parents and 4 biologic grandparents who are ethnically Japanese and born in JapanHave maintained a Japanese lifestyle, with no significant change since leaving Japan, including having access to Japanese food and adhering to a Japanese dietBe living <10 years outside of JapanHas a body mass index between 18 and 32 kg/m^2, inclusive, at the screening visitIs judged by the investigator to be in good health, as described in the protocolIs in good health based on laboratory safety testing obtained at the screening visit and approximately within 24 hours prior to administration of study drugKey Exclusion Criteria:History of clinically significant cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrine, hematological, psychiatric, neurological, or dermatologic disease, as assessed by the investigator, that may confound the results of the study or poses an additional risk to the participant by study participationPresents any concern to the study investigator that might confound the results of the study or poses an additional risk to the participant by their participation in the studyHospitalized for any reason within 30 days of the screening visitUsing the Modification of Diet in Renal Disease equation, has a glomerular filtration rate as described in the protocol at the screening visitHas alanine aminotransferase (ALT) or aspartate aminotransferase (AST) or total bilirubin above the upper limit of normal (ULN) range.Is a current smoker or former smoker, including e-cigarettes, who stopped smoking within 3 months prior to the screening visitHas a history of alcohol or drug abuse per investigator opinionIs positive for hepatitis C antibody and if so, positive for qualitative (ie, detected or not detected) hepatitis C virus ribonucleic acid (RNA) test at the screening visitNOTE: Other protocol defined inclusion / exclusion criteria apply