This study is testing a treatment called NT 201 on adults with noticeable neck muscles called platysma. Some people have more obvious neck bands, which can be described as moderate or severe. The study compares NT 201 to a placebo (a fake treatment) to see if it helps. It's divided into two parts: the Main Period (MP) and the Open Label Extension Period (OLEX).

To join, you need to have certain neck bands and a specific score on a test called MAPS-D. You can't join if you're allergic to the ingredients of NT 201 or have certain health conditions. Also, if you've had recent neck or face surgeries or plan to have cosmetic procedures soon, you can't participate.

• The study is divided into two parts, MP and OLEX.
• You can't join if you've recently had certain surgeries or plan any soon.
• If you have allergies to NT 201, you shouldn't participate.