Comparison study between tocilizumab and standard treatment in COVID-19

A new study by IRCCS Ospedale San Raffaele conducted by Corrado Campochiaro, immuno-reumatologist, and coordinated by Lorenzo Dagna, head of the Immunology, Rheumatology, Allergology and Rare Diseases Unit, assessed the efficacy and safety of the immunosuppressive drug tocilizumab. This is the first study to test the drug in COVID-19 using a control group, treated only with standard pharmacological protocol for COVID-19 patients hospitalized at Ospedale San Raffaele.

The results, published in the European Journal of Internal Medicine, showed that tocilizumab, although it may be useful in subjects with severe form of COVID-19 before admission to intensive care, did not significantly reduce mortality at 28 days compared to patients treated only with standard therapy.

The trial was carried out within the maxi observational clinical study on Covid-19 coordinated by Professor Alberto Zangrillo, director of the General Anaesthesia and ICU and Cardiothoraco-Vascular Anaesthesia Unit, and Professor Fabio Ciceri, deputy scientific director for clinical research and head of the Hematology and Medulla Transplantation Unit.


The clinical study

Tocilizumab is a commercial monoclonal antibody for rheumatoid arthritis that acts by blocking the production of Interleukin-6 (IL-6), an inflammatory molecule produced by the immune system. Since the first weeks of the pandemic, the drug - in the absence of specific drug therapies - has been used in an attempt to contain the hyper-inflammatory response caused by the new coronavirus.

The trial was conducted retrospectively on 65 patients with severe clinical conditions hospitalized outside the intensive care unit at San Raffaele. Most of the subjects were male, with an age of about 60-65 years. Of these, 33 received only the standard therapy - consisting of several drugs including hydroxychloroquine and the combination lopinavir/ritonavir (antivirals used in patients with HIV infection) - while 32 were treated, in addition to the standard therapy, with intravenous tocilizumab.


The results of the study

"We evaluated and compared safety and efficacy with a 28-day follow-up: the results obtained with tocilizumab, although encouraging, showed an overall clinical improvement and a reduction in mortality that was not statistically significant when compared with standard therapy" explains Corrado Campochiaro, first name of the study. In patients treated with tocilizumab, in fact, there was a clinical improvement in 69% of cases compared to 61% of those who had not received such treatment. On the other hand, bacterial and fungal infections seem to be slightly higher in the treated patients.

"The limit of the data obtained from the several trials published to date has been to test tocilizumab in the absence of an effective control group. In our study we compared tocilizumab with standard therapy, observing the reduction in mortality by half (from 33% to 15%), but this data did not achieve an adequate significance to draw definitive conclusions", specifies Lorenzo Dagna, study coordinator.

This means that to better understand the role of tocilizumab in Covid-19 we will have to wait for the results of the international trials. "Recently we have also obtained encouraging results from a study that shows the efficacy and safety of anakinra, a molecule that acts this time on IL-1, to switch off the excessive immune response caused by severe forms of COVID-19" concludes Dagna.