Raylumis: how it works and what it is used for

Raylumisis a treatment based ontanezumab, a monoclonal antibody againstnerve growth factordeveloped in the early 2000s for the treatment of pain in numerous bone diseases.

More specifically, tanezumab was conceived as aremedy for painrelated to osteoarthritis, a chronic disease that involves progressive damage to cartilage and surrounding tissues of the joints. Tanezumab acts as a nerve growth factor antagonist. It therefore preventsits bindingwith specific receptors of nerve cells responsible for the sense of pain related to the disease. Pfizer has also proposed this monoclonal antibody as a pain remedy for:

• Bone tumors;
• Interstitial cystitis;
• Chronic low back pain;

In the past, some studies on the active ingredient of Raylumis had highlighted some critical issues. In 2010, for example, Pfizer had to stop a Phase II study due to the worsening conditions of some patients. The aim of this study was to demonstrate the effectiveness of the monoclonal antibody in mitigating hip pain. Many of them also needed hip replacement to alleviate symptoms (source).

A year later, however,another studywould confirm the beneficial effects of the monoclonal antibody in the treatment of pain in patients suffering from hip osteoarthritis.

Raylumis is now thought to be administered to those patients who can no longer control pain by means ofnon-steroidal anti-inflammatories (NSAIDs) oropioid drugs (related tomorphine), as well as to anyone who is allergic to these treatments.

What studies has Pfizer presented for Raylumis?

From what we learn through EMA sources, in addition to the request for authorization for the European market, the pharmaceutical company Pfizer has also presented the results of some studies concerning3,021 individuals suffering from osteoarthritis (source).

Patients had chronic pain classified as moderate to severe in the lower joints, especially in thekneearea andhips. There were also individuals with serious problems concerning the functioning of the joints due to chronic pathology.

Why did EMA give a negative opinion?

Although the studies presented by Pfizer showed efficacy on pain, the EMA judged these results unsatisfactory. In fact, the improvement in pain in patients treated with the monoclonal antibody compared to those given placebowas minimal.

As if that were not enough, EMA then specified that there were no strong differences between the treatment based on tanezumab and those based on opioid drugs or NSAIDstags. Also onthe risk side, an increase in the incidence of acute progressive osteoarthritis and joint replacement (hip transplant) was observed in subjects who had received Raylumis.

In light of this, EMA rejected the authorization request presented by Pfizer as the studies had not yet correctly defined the greater benefitsof the therapy based on the monoclonal antibody tanezumab compared to the others envisaged for the same pathology. In addition, the observed risks still outweighed the benefits.

As stated above, Pfizer may request a review of studies within 15 days and possibly undertake new studies in order to reapply in the future.