Horse Allo 20

Horse Allo 20 is a veterinary medicine that contains allogeneic equine mesenchymal stem cells as active substance. It was to be available as a suspension for injection into a joint.

Horse Allo 20 was developed as a novel therapy medicine containing cells that have been manipulated so that they can be used to repair, regenerate or replace tissue.

Horse Allo 20 was expected to be used to treat lameness in adult horses with osteoarthritis. Osteoarthritis is a condition that causes swelling and pain in the joints and which is often associated with lameness.

The way that mesenchymal stem cells work has not been clearly established but published studies indicate that they have an anti-inflammatory action and may have an effect in regenerating tissue. This was expected to help control the inflammation and joint damage associated with osteoarthritis in horses, and so reduce lameness.

The applicant presented data from a field study involving horses from 2 years of age with osteoarthritis, where 37 horses were treated with Horse Allo 20 while 33 horses received a dummy treatment. The main measure of effectiveness was a reduction in 1 or more grades of lameness using a scoring system that runs from 1 to 5.

The CVMP noted that there were problems with the way the main study was designed and carried out, and concluded that the effectiveness of the medicine had not been sufficiently demonstrated. The CVMP was also concerned about the high number of side effects reported in the field study. Finally, the Committee had concerns about the way the medicine was manufactured and its quality ensured.

Following a request from the European Commission, the CVMP revised part of its opinion concerning compliance with Good Manufacturing Practice (GMP). The Committee removed its previous objection that the company did not comply with GMP but all other concerns remained. The CVMP was therefore of the opinion that the benefits of Horse Allo 20 did not outweigh its risks and recommended that it be refused marketing authorisation.