A real-world comparison of non-TNF targeted biologics has shown rituximab and tocilizumab are more effective than abatacept in patients with refractory rheumatoid arthritis (RA).
The data was from more than 3,000 RA patients enrolled in French rheumatology registries, previously treated with TNF inhibitors and followed for at least two years after initiation on one of the non-TNF inhibitors.
At two years, 68.6% and 63.4% of patients were still using rituximab and tocilizumab respectively without failure compared to 39.3% for abatacept.
More participants treated with rituximab or tocilizumab than with abatacept showed a good or moderate EULAR response.
The average durations of survival without drug failure were 19.8 months for rituximab, 19.1 months for tocilizumab and 15.6 months for abatacept.
Failure was defined as discontinuation of the drug, initiation of a combination of conventional disease modifying antirheumatic drugs (DMARDs), a new biologic or an increase in oral corticosteroids dose.
Rates of serious adverse events – 14.5% in rituximab patients, 11.6 % of tocilizumab patients and 16.2% of abatacept patients – did not differ between the groups.
The researchers said the observational data was valuable given that head-to-head randomised trials comparing the non-TNF biologics were unlikely in the future.
“Drug retention seems a good surrogate marker of the balance between effectiveness and adverse events and appears particularly adequate in registry studies and relevant in routine practice,” the study said.
Given the similar safety profile in the three patient groups, they concluded the higher drug retention rate of rituximab and tocilizumab compared with abatacept was related to greater effectiveness.
However the researchers said the rates of discontinuation on the non-TNF highlighted ‘the continued need for enlargement of the armamentarium of new biologic and targeted DMARDs in the treatment of rheumatoid arthritis’.