Assessment of the Efficacy of Stromal Vascular Fraction Treatment for Knee Osteoarthritis

The research consists on one-year follow-up prospective observational study. It involves male and female patients (over 18-years-old) with unilateral or bilateral knee osteoarthritis treated with intraarticular injection of stromal vascular fraction (SVF) treatment developed by Cellab Laboratory (Celstem®).

The aim of the study is to assess pain efficacy with SVF treatment for knee osteoarthritis patients. To assess pain, Visual Analogue Scale (VAS) is used.

Secondarily, the study aims to determine the differences pre-post treatment with SVF of the secondary outcomes measures: functionality, quality of life and disability. Is is used KOOS scale, Short Form-36 questionnaire (SF-36) and World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) to assess such measures, respectively. It also aims to describe and evaluate the regeneration of joint cartilage of each individual by systematic comparison of magnetic resonance imaging (MRI) before and one year after SVF treatment, measured by Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) scale. Moreover, specific sociodemographic and clinical factors that can predict or influence the therapeutic effects and its correlation to biological data (cellularity, immunophenotype, colony formation potency and sterility) will be identified. Adverse events or side effects related to the treatment will be reported.

Both primary and secondary outcome measures are evaluated prior to treatment, at 1-month, 6-months and one year after treatment except for the assessment of disability and the radiological features of the articular cartilage, which are performed only before and one year after. The radiological assessment according to MOCART classification is performed by a radiologist. This specialised physician is not aware of patients evolution in order to obtain minimize subjective bias. In addition, SVF product biological data, such as the amount of sample of extracted adipose tissue, effective dose, cellularity, immunophenotype, potency sample colonies and sterility, are collected to better describe the product and to be able to correlate the clinical effect with biological features.

The study was approved by the Clinical Research Ethics Committee of Nostra Senyora de Meritxell Hospital on September 20th, 2018. It is expected to last 4 years, from 2018 to 2022.

The sample size is determined using the Sample Size Calculator GRANMO (Version 7.12. April 2012). A random sample of 77 individuals affected of knee osteoarthritis is expected to be sufficient to estimate, with 95% confidence and accuracy of +/- 5 percentage units, a population percentage that is expected to be around 5% in the study population (population of the regions of Andorra and Catalonia). A required replacement rate of 5% is expected.

Once treatment indication is been performed and accepted by the patient, patients who meet the inclusion criteria (see Eligible Criteria) sign the informed consent. Personal data transfer consent to medical team is also signed.

Patients can be withdrawn if they do not complete the questionnaires in pre-established time and form or if its tracking is lost. Withdrawal of the patient does not represent any prejudice to the patient in the control of his disease or in its treat by the medical team or the Laboratory.

For clinical data collection, patient's medical history and physical examination, are collected by the principal investigator (PI) or collaborators in every follow-up medical visits. For a better patient compliance with the study protocol, a web platform has been developed (https://www.cellab.com/escalas-de-dolor). It has been designed by PI aided by an external computer team. It allows the virtual patient performance of functional scales all along the study protocol. This tool dumps all data entered by patients into an Excel database, which can be exported for statistical analysis by PI. In addition, the platform warns every time a patient is supposed to fill the questionnaires or even when they do not comply in time and / or form established.

Despite being an observational study, the object under study is a specific treatment of regenerative medicine: SVF treatment developed by Cellab Laboratory (Celstem®). The main feature of this treatment is that it raises the importance of this study is that the product used is made following strict guidelines manufacturing that ensure its reproducibility, quality and safety. It is approved by the Andorra Government authorities for its application.

It should be noted that the procedure for obtaining, preparing and applying Celstem® it is always performed by the same professionals: a plastic surgeon, biotechnologist and a physical medicine and rehabilitation physician (who appears to be the PI), respectively, in order to avoid interpersonal biases in the process.

Obtaining Celstem® requires abdominal fat liposuction. It is performed by a plastic surgeon underneath sedation and local anesthesia in an operating room, under the supervision of a anesthetist. The amount adipose tissue extracted varies according to availability in each patient, with a minimum extraction of 200ml. The extracted tissue is immediately transported (within 1 hour) to Cellab Laboratory in standardized refrigeration conditions. A traceability certificate is filled to ensure its conservation.

The product's preparation is carried out exclusively in a laboratory cleanroom, following American Association of Blood Banks (AABB) standards conditions of hygiene and biological safety. It requires an exhaustive washing of the fat extracted with saline solution in order to remove both residues of blood or lidocaine and adrenaline used in the extraction process. Then the fat is concentrated and mixed with the enzymatic digestion solution (consisting of collagenase at 0.75 mg / mL). It is all incubated at 37 °C and stirred for 30-40 minutes. When this process is finished, collagenase is inactivated through human albumin and then again thoroughly washed with saline solution to remove the remnants of undigested fat and collagenase. A concentrated cell suspension in a reduced volume is obtained.

Once ready, the product returns at the clinic, again under proper refrigeration conditions and with the certificate of traceability correctly complimented to ensure its proper conservation. The application of the treatment is carried out on the same day of the extraction, in some point within 6 hours after the extraction. Under sterility measures, intraarticular infiltration of SVF treatment (Celstem®) is performed at affected knee or knees. Previous synovial fluid aspiration is performed, if required. Once the procedure is completed, rehabilitation recommendations and clinical follow-up information is provided.