Background and importance In June 2018, our HIV regional working group, in a programme to improve the efficiency of antiretroviral therapy (ART), recommended changing from a single tablet regimen (STR) with abacavir/lamivudine/dolutegravir (ABC/3TC/DTG) once daily to abacavir/lamivudine (ABC/3TC) generic plus dolutegravir (DTG) once daily.

Aim and objectives To evaluate the degree of implementation of this strategy and the impact in terms of adherence and efficiency after 9 months.

Material and methods The retrospective descriptive study (June 2018–March 2019) included all HIV patients treated with STR ABC/3TC/DTG. To measure adherence, the consumption and dispensation registry of the pharmacy service software programme was used. Patients with a value >95% were considered adherent. The analytical variables collected were viral load (VL, copies/mL) and CD4 lymphocytes (cells/µL) (last available analytical before the change and at least 3 months later). Costs considered were hospital average prices according to the regional public tender.

Results Fifty-two patients, mean age 51.56 years, receiving treatment with ABC/3TC/DTG, were included. The change in ART was carried out in all patients.

Forty-four patients (84.6%) were adherent (>95%) before the switch and remained so after the change. We detected 8 (15.4%) patients with suboptimal adherence( <95%), with a mean adherence prior to the change of 81.5% (SD 5.3%) and after the change 84.3% (SD 6, 2%). Before the change, 49 patients (94.2%) presented undetectable VL, 2 patients (3.8%) had between 50 and 200 copies/mL and 1 patient (1.9%) had VL >200 copies/mL. After the change, 46 patients were evaluated (6 did not have analytics), 43 (93.4%) with undetectable VL, 2 (4.3%) with VL 50–200 copies/mL and 1 patient (2.1%) with VL >200 copies/mL.

The average level of LCD4 in the pre-change analysis was 808.67/µL (SD 205) and after the switch 785.4/µL (SD 308).

Cost savings were 132€/patient/month (1584€/patient/year). The estimated savings for the hospital since this efficiency measure was implemented until March 2019 was 41 000€.

Conclusion and relevance The results of the study, despite its limitations, demonstrated that after the switch, levels of virological suppression were maintained with a significant reduction in healthcare costs without affecting patient adherence to ART. More exhaustive and long term studies should be carried out to corroborate these results.

References and/or acknowledgements No conflict of interest.