Healthy Vollunteer

This is a Phase I, single-center, randomized, double-blind, placebo-controlled SAD/MAD study to evaluate safety, tolerability, and PK of Intravenously Administered PTT-121 in healthy Chinese adults.

Nonspecific low back pain is a common musculoskeletal problem that also affects many young adults, including university students. It can negatively impact academic performance, daily life, and overall well-being. Research shows that stabilization exercises targeting the lumbar multifidus muscle play an important role in rehabilitation, but it is unclear whether modified versions of these exercises may provide additional benefits. This study will investigate a simple modification of the traditional "bird-dog" exercise, called the "Multifidus Lift Exercise." In this version, participants maintain the contralateral knee about 10 cm above the ground while in a four-point kneeling position. This adjustment is expected to increase multifidus activation and improve back endurance. University students aged 18-25 with nonspecific low back pain will participate in a 6-week supervised program, performing the exercise twice weekly. A healthy control group without low back pain will also be included. The main outcome will be back extensor muscle endurance (Biering-Sørensen Test). In participants with back pain, pain intensity (Visual Analog Scale) and functional disability (Oswestry Disability Index) will also be measured. The study aims to determine whether this low-cost, practical, and time-efficient exercise can improve muscle endurance, reduce pain, and decrease disability in young adults with low back pain. Results may provide evidence for an effective and accessible preventive and therapeutic approach in student populations.