RESUMEN
BACKGROUND: In low- and middle-income countries (LMICs), a substantial unmet need for affordable single-tablet regimen (STR) options remains. Rilpivirine (RPV, TMC278) is formulated in a low-cost STR with tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC). OBJECTIVES: Switching at Low HIV-1 RNA into Fixed Dose Combinations (SALIF) compared RPV with efavirenz (EFV), both as STRs with TDF and FTC, in maintaining virologic suppression. METHODS: SALIF was a phase 3b, randomised, open-label, non-inferiority study in virologically suppressed adults (HIV-1 RNA < 50 copies/mL) on non-nucleoside reverse transcriptase inhibitor (NNRTI)-based first-line antiretroviral therapy (ART) in Cameroon, Kenya, Senegal, South Africa, Uganda and Thailand. Patients (N = 426), stratified by NNRTI use, were randomised 1:1 to receive TDF/FTC/RPV (300/200/25 mg qd) or TDF/FTC/EFV (300/200/600 mg qd). Primary endpoint was proportion of patients with virologic suppression (HIV-1 RNA <â¯400 copies/mL) at week 48 (intent-to-treat, modified Food and Drug Administration Snapshot, 10% non-inferiority margin). RESULTS: Patients received TDF/FTC/RPV (n = 213) or TDF/FTC/EFV (n = 211). At week 48, virologic suppression was maintained in 200/213 (93.9%) patients in the RPV arm and 203/211 (96.2%) in the EFV arm (difference -2.3%; 95% confidence interval: -6.4, +1.8), demonstrating non-inferiority of TDF/FTC/RPV. One patient in each arm experienced virologic failure without treatment-emergent resistance. Twenty-seven patients discontinued prematurely (8.0% RPV vs. 4.7% EFV), the most frequent reasons being adverse events (3.3% vs. 0.5%, respectively), site closure (1.9% vs. 0.5%), loss to follow-up (0.9% vs. 1.4%) and consent withdrawal (0.9% vs. 1.4%). CONCLUSION: In adults with suppressed viral load on first-line NNRTI-based ART in LMICs, switching to an STR of TDF/FTC/RPV was non-inferior to TDF/FTC/EFV in maintaining high rates of viral suppression with a comparable tolerability profile.
RESUMEN
The amphibian Xenopus laevis can adapt the color of its skin to the light intensity of the background. A key peptide in this adaptation process is alpha-melanophore-stimulating hormone (alpha-MSH), which is derived from proopiomelanocortin (POMC) and released by the endocrine melanotrope cells in the pituitary pars intermedia. In this study, the presence of alpha-MSH in the brain, cranial placode derivatives, and retina of developing Xenopus laevis was investigated using immunocytochemistry, to test the hypothesis that POMC peptide-producing neurons and endocrine cells have a common embryonic origin and a common function, i.e., controlling each other's activities and/or being involved in the process of physiological adaptation. The presence of alpha-MSH-positive cells in the suprachiasmatic nucleus, ventral hypothalamic nucleus, epiphysis, and endocrine melanotrope and corticotrope cells, which are all involved in regulation of adaptation processes, has been detected from stage 37/38 onward. This is consistent with the presumed common origin of these cells, the anterior neural ridge (ANR) of the neural-plate-stage embryo. The olfactory epithelium and the otic and epibranchial ganglia also contain alpha-MSH, indicating that these placodal derivatives originate from a common placodal domain continuous with the ANR. Furthermore, we demonstrate the presence of alpha-MSH in a subpopulation of retinal ganglion cells (RGCs), which is possibly also derived from the ANR. Immunoreactivity for alpha-MSH in RGCs that are located in the dorsal part of the retina is dependent on the background light intensity, suggesting that these cells are involved in the regulation of background adaptation. Taken together, the results support the hypothesis that POMC peptide-producing cells have a common embryonic origin and are involved in adaptation processes.