Withdrawn (No Participants Enrolled)

To evaluate the safety and feasibility of adipose-derived regenerative cells injected into tears of the hamstring muscle.

The RECOVER Clinical Trial is a prospective, randomized, multi-center device trial intended to assess safety and feasibility, and inform dose selection in preparation for a pivotal trial. Subjects that have Grade II tears of the hamstring will be evaluated for eligibility in this study.

Part A of the trial will be an open-label, safety, feasibility and dose-escalation study to assess whether the treatment approach (liposuction, cell processing and injection) is feasible in athletic patients at one or both doses of ADRCs.

Part B of the trial is contingent on successful completion of Part A and is a multicenter, randomized, double blind trial of both doses of ADRCs vs. placebo.

In both parts of the study, following informed consent and screening evaluations, eligible subjects will undergo pre-operative testing. Subjects will then undergo liposuction under general or local anesthesia. Lipoaspirate will be processed in the Celution System to isolate and concentrate ADRCs for immediate intramuscular administration under ultrasound guidance.

The first 5 patients of Part A will receive 0.2 million cells/kg body weight (maximum of 20 million cells) while the second 5 patients will receive 0.4 million cells/kg body weight (maximum of 40 million cells).

If the study is shown to be safe and feasible in Part A then patients in Part B of the study will be randomly assigned to receive one of two doses of ADRCs or a visually-matched placebo in a 1:1:1 ratio. If they receive the placebo they will undergo a liposuction and sham intramuscular injection procedure in which they will receive placebo.Part B will receive placebo, 0.2 million cells/kg body weight (maximum of 20 million cells), or 0.4 million cells/kg body weight (maximum of 40 million cells).

Patients in Part A of the study will be followed through to 90 days post-procedure. Patients in Part B of the study will be followed through to 24 months post-procedure.

Inclusion Criteria:

• Grade II tears (≥5%) of the hamstring
• Weakness or inability to use affected muscle
• Ability to safely undergo liposuction

Exclusion Criteria:

• Tears restricted to the ligament (i.e. no muscle tear)
• Known spine or disc disease or sciatic nerve disease
• Known neuromuscular disease
• Pregnant or lactating status
• Any condition requiring immunosuppressive medication or use of systemic steroids
• Known history of HIV, or has active Hepatitis B or active Hepatitis C
• Cancer requiring chemotherapy or resection within the last 5 years (other than basal cell carcinoma)