Adherence of denosumab treatment for low bone mineral density in Japanese people living with HIV: a retrospective observational study.

BACKGROUND: Long-term care issues, specifically metabolic bone disorders, are a concern for people living with human immunodeficiency virus (PLWH) who undergo life-long antiretroviral therapy (ART). Previous clinical trials with denosumab, an anti-RANKL antibody inhibitor, have revealed its effectiveness in increasing bone mineral density (BMD) in patients with osteoporosis. However, there are limited data on adherence and effectiveness of denosumab treatment for osteoporosis in PLWH. Hence, this study aimed to investigate the adherence and effectiveness of denosumab treatment for osteoporosis in Japanese PLWH. METHODS: This study is a retrospective exploratory analysis of 29 Japanese PLWH who initiated denosumab treatment for osteoporosis, between 2013 and 2021. The study included patients who received at least one dose of denosumab every 6 months. Adherence and persistence were defined as receiving two consecutive injections of denosumab 6 months ± 4 weeks apart and 6 months + 8 weeks apart, respectively. The primary outcome measure of the study was the adherence of denosumab treatment for 24 months. The secondary outcome measures included treatment persistence and BMD. The period after January 2020 was defined as the coronavirus disease 2019 (COVID-19) pandemic period, and its impact on adherence was investigated. RESULTS: The treatment adherence rates at 12 and 24 months were 89.7% and 60.7%, respectively. By contrast, the treatment persistence at 12 and 24 months was 100% and 85.7%, respectively. More patients in the group who initiated denosumab treatment after the COVID-19 pandemic reached non-adherence than in the group who initiated denosumab treatment before the pandemic. BMD at the lumbar spine and femoral neck significantly increased compared to that at baseline, with median percentage changes of 8.7% (p < 0.001) and 3.5% (p = 0.001), respectively. CONCLUSIONS: The results showed that patients in the study had a high rate of non-adherence but a lower rate of non-persistence. Additionally, PLWH on ongoing ART experienced increased BMD with denosumab treatment. This study provides an opportunity to improve future strategies for denosumab treatment in the Japanese PLWH.

Potential drug-drug interactions in the era of integrase strand transfer inhibitors: a cross-sectional single-center study in Japan.

BACKGROUND: Potential drug-drug interactions (PDDIs) commonly occur because of aging and comorbidities in people living with human immunodeficiency virus (HIV; PLWH). Protease inhibitors and non-nucleoside reverse transcriptase inhibitors have been reported to cause PDDIs in these patients. However, there are few reports of PDDIs in the era of treatment using integrase strand transfer inhibitors. Therefore, we investigated PDDIs in Japanese PLWH receiving antiretroviral drugs (ARVs). METHODS: This was a cross-sectional observational study conducted in Japanese outpatients. All eligible patients who had received ARV therapy for at least 48 weeks were enrolled. The primary endpoint was the incidence of PDDIs detected using the Lexicomp® interface. RESULTS: Of the 71 eligible patients, 51 (71.8%) were prescribed concomitant non-ARV medications. In 21 patients (29.6%), PDDIs with the potential to reduce the effects of ARVs occurred, although the HIV load was suppressed in all cases. Polypharmacy (the use of ≥5 non-ARVs) was observed in 25 patients (35.2%). There was a significantly higher median number of non-ARV medications in the PDDI group than in the non-PDDI group (6 vs. 3, P <  0.001). Furthermore, the proportion of patients on polypharmacy was significantly higher in those with PDDIs than in those without PDDIs (81.0% vs. 26.7%, P <  0.001). CONCLUSIONS: The incidence of PDDIs is relatively high in Japanese PLWH, even in the era of treatment using integrase strand transfer inhibitors. Therefore, it is important for patients and health care providers to be constantly aware of PDDIs associated with ARV treatment.

Cellular function and signaling pathways of vascular smooth muscle cells modulated by sphingosine 1-phosphate.

Sphingosine 1-phosphate (S1P) plays important roles in cardiovascular pathophysiology. S1P1 and/or S1P3, rather than S1P2 receptors, seem to be predominantly expressed in vascular endothelial cells, while S1P2 and/or S1P3, rather than S1P1 receptors, seem to be predominantly expressed in vascular smooth muscle cells (VSMCs). S1P has multiple actions, such as proliferation, inhibition or stimulation of migration, and vasoconstriction or release of vasoactive mediators. S1P induces an increase of the intracellular Ca2+ concentration in many cell types, including VSMCs. Activation of S1P3 seems to play an important role in Ca2+ mobilization. S1P induces cyclooxygenase-2 expression in VSMCs via both S1P2 and S1P3 receptors. S1P2 receptor activation in VSMCs inhibits inducible nitric oxide synthase (iNOS) expression. At the local site of vascular injury, vasoactive mediators such as prostaglandins and NO produced by VSMCs are considered primarily as a defensive and compensatory mechanism for the lack of endothelial function to prevent further pathology. Therefore, selective S1P2 receptor antagonists may have the potential to be therapeutic agents, in view of their antagonism of iNOS inhibition by S1P. Further progress in studies of the precise mechanisms of S1P may provide useful knowledge for the development of new S1P-related drugs for the treatment of cardiovascular diseases.