Is it possible to still achieve some type of improvement after all this time?

Sculpltra is a stimulating agent that normally does require several treatment sessions spaced over time to produce gradual results. Generally speaking, the more treatments that are done, the more volume that can be added. More information would be needed to comment on your particular treatment. Pictures of you before treatment, the details of your treatments and pictures of you after the treatments would be helpful to give you more advice.

Dear RealSelf03185,
The aging process is said to lose 1% of collagen per year after 30 years old. Without photos and examination, I am unable to identify the cause of your concerns. Is it skin laxity, skin folding, wrinkling, desired tightening, subcutaneous descent, festooning and many other signs of aging? In my experience, Sculptra requires 2 to 3 sessions during the first year and maintenance of one session yearly thereafter. This does not obviate interim fillers, threadlift, retinoids, chemical peels, surgical lifting and other options to further rejuvenate your face and neck. Please consult with your Practitioner / Board Certified Plastic Surgeon. All the best.