There is a clinical trial for treatment of lipomas with Collagenase Clostridium histolyticum (CCH) that is currently recruiting patients.  CCH has been approved by FDA for treatment of Dupuytren's Contracture and Peyronie's Disease.  As listed on Clinicaltrials.gov the sites are:
1) R Shack MD, Vanderbilt Medical Center, Nashville Tenn.  Phone 615-343-8426
2) Z Gerut MD, Hewlett NY. Phone 516-295-2100.
The following link has ore information on this clinical trial:

https://clinicaltrials.gov/ct2/show/NCT02249052?term=lipoma&rank=3