Spherox

Spherox is available as a suspension for implantation into the knee joint. The medicine is prepared specifically for each individual patient and must be given by a qualified doctor in a medical facility.

To prepare the medicine, a small sample is taken by arthroscopy (a type of keyhole surgery) from the patient’s cartilage in the knee. The cartilage cells are then grown in the laboratory to prepare a suspension of chondrocyte spheroids. During another arthroscopy, the medicine is placed into the damaged area of the patient’s cartilage in the knee. The chondrocyte spheroids attach to the cartilage within 20 minutes. Patients treated with Spherox should follow a specific rehabilitation programme, including physiotherapy. This allows the chondrocyte spheroids to fill in the cartilage defect.

The medicine can only be obtained with a prescription.

Cartilage in the knee can be damaged because of an accident, such as a fall or a sports injury. Spherox contains spheroids made from the patient’s own healthy cartilage cells. When the spheroids are implanted into the patient’s knee cartilage, they attach to the area of the defect and produce new tissue, thereby repairing the defects in the knee.

Spherox has been shown to improve patients’ symptoms and knee function in two studies in adults between 18 and 50 years of age. The main measure of effectiveness was the KOOS (knee injury and osteoarthritis outcome score), which is graded on a scale from 0 to 100 (where 0 means severest symptoms and 100 means no symptoms). The KOOS was self-measured by patients, who rated the severity of their symptoms such as pain, impact on daily living, sport and recreational activities, and quality of life.

In the first study involving 100 adults, Spherox was compared with microfracture (a type of surgery used to treat defects in cartilage). The knee cartilage defects were between 1 and 4 cm2 in size. Data from this study showed that Spherox improved the outcome score by 22 points to 28 points until 5 years after treatment and was as effective as microfracture.

The second study looked at 73 adults with large cartilage defects of the knee from 4 to 10 cm². All these patients received treatment with Spherox, as microfracture is not recommended to repair such large defects. In this study, patients’ outcome scores with Spherox improved by 16 points in the first year and further improvements were seen up to three years after treatment and remained stable until five years after treatment.

A third study looked at the treatment effect with Spherox in 105 adolescents aged between 15 and 17 years with cartilage defects of the knee joint. Overall, the results indicated that there was no major difference in terms of effectiveness between the adolescents included in this study and the young adults (from 18 to 34 years of age) who participated in the previous two studies.

The most common side effects with Spherox (which may affect up to 1 in 10 people) are bone marrow oedema (accumulation of fluid in the bone marrow), arthralgia (joint pain), joint effusion (accumulation of fluid in the knee),swelling of the joint and pain. For the full list of side effects of Spherox, see the package leaflet.

Spherox must not be used in patients with primary generalised osteoarthritis or with advanced osteoarthritis of the knee (conditions causing swelling and pain in the joints) and in patients whose bones in the knee joint are still growing. It must also not be used in patients infected with hepatitis B, C and/or HIV.

Spherox has been shown to be effective at treating knee cartilage defects between 1 and 10 cm2 in size. Using chondrocyte spheroids that attach to the knee cartilage allows for less invasive surgery. The safety profile was considered acceptable; most side effects are expected to be due to the surgery. The European Medicines Agency therefore decided that Spherox’s benefits are greater than its risks and it can be authorised for use in the EU.

The company that markets Spherox will ensure that all surgeons and other healthcare professionals handling or using the medicine receive training materials on how to use and store it, and that systems are in place to ensure that only healthcare professionals trained in using Spherox can use it, and that patients are tested to ensure they meet strictly defined clinical criteria. The training materials will include guidance on how to safely collect and handle the cartilage sample from patients, implant Spherox as well as how to inform and follow up patients.

Recommendations and precautions to be followed by healthcare professionals and patients for the safe and effective use of Spherox have also been included in the summary of product characteristics and the package leaflet.

As for all medicines, data on the use of Spherox are continuously monitored. Side effects reported with Spherox are carefully evaluated and any necessary action taken to protect patients.

Spherox received a marketing authorisation valid throughout the EU on 10 July 2017.