No abstract

Cryptococcus neoformans ( C. neoformans var. grubii ) is an environmentally acquired pathogen causing 181,000 HIV-associated deaths each year. We sequenced 699 isolates, primarily C. neoformans from HIV-infected patients, from 5 countries in Asia and Africa. The phylogeny of C. neoformans reveals a recent exponential population expansion, consistent with the increase in the number of susceptible hosts. In our study population, this expansion has been driven by three sub-clades of the C. neoformans VNIa lineage; VNIa-4, VNIa-5 and VNIa-93. These three sub-clades account for 91% of clinical isolates sequenced in our study. Combining the genome data with clinical information, we find that the VNIa-93 sub-clade, the most common sub-clade in Uganda and Malawi, was associated with better outcomes than VNIa-4 and VNIa-5, which predominate in Southeast Asia. This study lays the foundation for further work investigating the dominance of VNIa-4, VNIa-5 and VNIa-93 and the association between lineage and clinical phenotype.

Background: Cryptococcal meningitis is a leading cause of death in HIV-infected patients. International treatment guidelines recommend induction therapy with amphotericin B and flucytosine. This antifungal combination is most effective, but unfortunately flucytosine is expensive and unavailable where the burden of disease is greatest. Where unavailable, guidelines recommend treatment with amphotericin and fluconazole, but this is less effective, with mortality rates of 40-50%. Faster rates of clearance of yeast from cerebrospinal fluid (CSF) are associated with better outcomes - improving the potency of antifungal therapy is likely to be an effective strategy to improve survival. Tamoxifen, a selective estrogen receptor modulator used to treat breast cancer, has anti-cryptococcal activity, appearing synergistic when combined in vitro with amphotericin, and fungicidal when combined with fluconazole. It is concentrated in the brain and macrophages, off-patent, cheap and widely available. We designed a randomized trial to deliver initial efficacy and safety data for tamoxifen combined with amphotericin and fluconazole. Method: A phase II, open-label, randomized (1:1) controlled trial of tamoxifen (300mg/day) combined with amphotericin (1mg/kg/day) and fluconazole (800mg/day) for the first 2 weeks therapy for HIV infected or uninfected adults with cryptococcal meningitis. The study recruits at Cho Ray Hospital and the Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam. The primary end point is Early Fungicidal Activity (EFA-the rate of yeast clearance from CSF), over the first two weeks of treatment. 50 patients will be recruited providing ≈80% and 90% power to detect a difference in the EFA of -0.11 or -0.13 log10CFU/ml/day, respectively. Discussion: The results of the study will inform the decision to proceed to a larger trial powered to mortality. The size of effect detectable has previously been associated with reduced mortality from this devastating disease. Particular side effects of interest include QT prolongation. Trial registration: Clinicaltrials.gov NCT03112031 (11/04/2017)

Dexamethasone may slow fungal clearance and worsen outcomes by increasing the rate of decline of TNF-α concentration.

Robust population pharmacokinetic (PK) data for fluconazole are scarce. The variability of fluconazole penetration into the central nervous system (CNS) is not known.