New ATMP to treat Cartilage Defects in the Knee

EMA (European Medicines Agency) has recommended to grant a marketing authorisation in the European Union (EU) for a new ATMP (advanced therapy medicinal product) to treat adult patients who have symptomatic articular cartilage defects in the femoral condyle (the ball-shaped end of the thigh bone in the knee) and the patella (knee cap), where the size of the affected area is no larger than 10 cm².

Spherox is an ATMP composed of spheroids, i.e. spherical aggregates of chondrocytes (cells that are found in healthy cartilage). In this therapy, a small piece of cartilage is excised from the healthy cartilage and chrondrocyte spheroids are produced in a laboratory. These spheroids are then inserted arthroscopically in the patient knee where they form new tissue to heal the defect.

The effects of Spherox were studied in two clinical trials, with patients between 18 and 50 years of age. The first study, a phase II trial, included 75 patients with cartilage defect sizes from 4 to 10 cm² and, the second, a phase III trial, involved 102 patients with defect sizes from 1 to 4 cm². The effect of the treatment was assessed using the Knee injury and Osteoarthritis Outcome Score (KOOS) questionnaire which evaluates patients’ views on their knee-associated problems, such as pain, impact on daily living, sport and recreational activities, and quality of life. Statistically significant improvement of the score was seen in both studies.

Spherox was assessed by the Committee for Advanced Therapies (CAT), EMA’s specialised scientific committee for ATMPs, such as gene or cell therapies. At its May 2017 meeting, the CAT recommended a positive opinion for Spherox to the Committee for Medicinal Products for Human Use (CHMP). The CHMP agreed with the CAT’s recommendation and adopted a positive opinion for the authorisation of Spherox across the EU at its 15-18 May 2017 meeting.