Document resource
Objectives The REGENCY trial ( NCT04221477) evaluated obinutuzumab plus standard therapy (OBI+ST) compared with placebo plus ST (PBO+ST) in adults with active lupus nephritis (LN). OBI+ST resulted in a significantly higher proportion of patients achieving a complete renal response at Week 76, with a manageable safety profile for obinutuzumab. This study aimed to further characterise the occurrence of serious infections (SIs) during the REGENCY trial.Methods Adults with biopsy-proven active LN were randomized 1:1 to receive OBI+ST or PBO+ST. The incidence, severity and types of infections were determined by site investigators, excluding previously reported COVID-19 infections. Vaccination status and use of prophylactic treatment (antibiotic or antiviral, initiated prior to or during study treatment) were reported by site investigators. Analyses included all safety-evaluable patients who received at least 1 dose of study treatment, grouped according to the treatment received.Results In REGENCY, 33 (12.3%) patients experienced at least one SI (23 [16.9%] in the OBI+ST arm and 10 [7.6%] in the PBO+ST arm). The median time to onset of SIs was 402 days (OBI+ST arm) and 87 days (PBO+ST arm), with median resolution time of 18 and 8 days in each arm, respectively ( table 1).Antibiotic and/or antiviral prophylaxis was used in 23 patients (11 [8.1%] in the OBI+ST arm, 12 [9.1%] in the PBO+ST arm), with no impact on SI rates compared with patients who did not receive prophylactic treatment. Although the vaccination rate was low (3 patients (2 [1.5%] in the OBI+ST arm, 1 [0.8%] in the PBO+ST), no vaccinated patients experienced a non-COVID-19 SI. The types of SIs were diverse and similar across both arms, consistent with expectations for this patient population (table 1). Besides COVID-19, the most common SIs were pneumonia, urinary tract infections and gastroenteritis.Abstract PO:11:279 Table 1Serious Infections in the REGENCY trialConclusions Although the incidence of SI was higher in the OBI+ST arm compared with the PBO+ST arm, the nature of infections was similar and manageable in routine clinical practice. While no clear benefit was shown by antibiotic/antiviral prophylaxis, vaccinations did appear to have protective effects against SIs. These results suggest that OBI can be used in a vaccinated population, as recommended by the latest EULAR guidelines.