Background and importance The aim of rheumatological diseases (RD) treatment should be clinical remission (CR) or alternatively a state of low level of clinical activity. The treatment of RD with a ‘treat to target’ (T2T) strategy consists of measuring and recording disease activity at each visit. If the patient has not reached the desired goal, therapeutic adjustments should be made to achieve it, and if the patient reaches CR then optimisation strategies (OS) can be performed: spacing or dose reductions.

Aim and objectives Measure the impact of T2T strategy in terms of effectiveness, safety and economic saving in rheumatological patients (RP) treated with biological agents (BA).

Material and methods A retrospective analysis was conducted in RP treated with BA with at least 3 months of treatment since April 2009 to August 2021. We registered: sex, age, type of RD, responder patients: DAS-28 <3.2, BASDAI <4; patients with CR: DAS-28 <2.6, BASDAI <2, median duration of treatment (DOTm), adverse events (EA), proportion of patients with OS, intensifications, adherence and economic saving obtained with OS. Direct costs between the use of standard dose instead of optimised dose were compared to calculate the economic saving.

Results 86 patients were included: 51% were male, median age was 58 years (IQR 28–84 years). The most prevalent pathology was rheumatoid arthritis (RA) with 60.56% of patients, followed by spondyloarthritis (SpA) in 22% and psoriatic arthritis (PA) in 17.44%. 93% (80/86) were responders with a DOTm of 50.7 months: CR was achieved in 73.75% (59/80) of responders and 4.65% (4/86) required dose intensification. Adherence was adequate in 95% of the patients.

Of all responders, 30% (24/80) were optimised: 70.83% (17/24) RA, 16.66% (4/24) PA and 12.5% (3/24) SpA. T2T has allowed an overall cost reduction of 27.4% compared with treatment with standard guidelines, meaning a total saving of €392 495 in the study period. AE was detected in 11.63% (10/86) of the patients, the most frequent being: infections (4.65%; 4/86) and local reactions (2.33%; 2/86).

Conclusion and relevance The T2T strategy in RP means an expenditure reduction with a huge optimisation of the resources available in our hospital guaranteeing the patient’s health results.

Conflict of interest No conflict of interest