JST-010

The goal of this clinical trial is to learn if a single dose of the study drug, JST-010, is safe and tolerable when administered by injection into the arm or thigh muscle of healthy men and women aged 18 to 55. The main questions it aims to answer are:
* Is a single injection of JST-010 safe?
* What is the concentration of the JST-01 in the blood over time?
* Do antibodies to JST-010 develop following a dose of JST-010?
Researchers will compare JST-010 to Placebo to see if there are any differences in the safety and tolerability of a single dose at different dose levels.
Participants will be confined to the clinic for the first 3 days. They will receive an injection on the second day, and then return for 9 more visits over the period of 1 year for:
* Physical exam with vital signs
* Electro-cardiogram (ECG)
* Bood collection for clinical labs and research samples
* Urine sample
* Assessment of potential adverse effects and medications taken