The purpose of this study is to: * evaluate the safety, tolerability, efficacy, pharmacokinetics (PK), and pharmacodynamics (PD) of single ascending doses of ALN-2232 in patients with obesity * evaluate the safety, tolerability, efficacy, PK, and PD of multiple doses of ALN-2232 in patients with obesity * evaluate the safety, tolerability, efficacy, PK, and PD of multiple doses of ALN-2232 co-initiated with tirzepatide in patients with obesity