ABSTRACT
We conducted an open-label, randomized clinical trial to assess parasite clearance times (PCT) and the efficacy of 4 mg/kg (group 1, n = 22) and 2 mg/kg (group 2, n = 22) of oral artesunate for three days followed by artemether-lumefantrine in patients with uncomplicated Plasmodium falciparum malaria at Xepon Interdistrict Hospital, Savannakhet Province in southern Laos. Slides were read in duplicate. The overall mean (95% confidence interval; range) PCT in hours was 23.2 (21.2-25.3; 12-46) and 22.4 (20.3-24.5; 12-46) for the first and second microscopists, respectively (P = 0.57). Ten (23%) patients remained parasitemic on day 1 after treatment (4 [18%] in group 1 and 6 [27%] in group 2; P = 0.47). No patient had patent asexual parasitemia on the second and third days of treatment. The 42-day polymerase chain reaction-corrected cure rates were 100% in both treatment groups. Serious adverse events did not develop during or after treatment in any patients. In conclusion, no evidence of P. falciparum in vivo resistance to artesunate was found in southern Laos.
Subject(s)
Antimalarials/therapeutic use , Artemisinins/therapeutic use , Drug Resistance , Plasmodium falciparum/drug effects , Administration, Oral , Adolescent , Adult , Aged , Artemether, Lumefantrine Drug Combination , Artesunate , Child , Drug Combinations , Drug Therapy, Combination , Ethanolamines , Female , Fluorenes/therapeutic use , Follow-Up Studies , Humans , Laos/epidemiology , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Male , Middle Aged , Plasmodium falciparum/pathogenicity , Treatment Outcome , Young AdultABSTRACT
Previous studies revealed that HIV-1 CRF01_AE viruses derived from antiretroviral drug-naïve Thai patients contained several protease (PR) inhibitor (PI) resistance-associated mutations. In this report, we examined the sustained appearance of drug resistance-associated mutations in CRF01_AE PR and reverse transcriptase (RT). Peripheral blood samples were collected every 3 months from April 2008 to April 2009 from 39 HIV-1-infected Thai patients, including 17 drug-naive and 22 RT inhibitors (RTIs)-treated individuals, and polymerase chain reaction-mediated-amplification and sequencing analysis of the viral genome encoding PR and RT were performed. We successfully analyzed the deduced amino acid sequence of CRF01_AE PR and RT derived from samples continuously collected from 15 drug-naïve and 20 RTIs-treated patients. Drug resistance-associated mutations were continuously detected in CRF01_AE PR derived from most patients. The continuous appearance of such PR mutations was observed not only in the proviral DNA genome derived from peripheral blood mononuclear cells, but also in the viral RNA genome of plasma virus. In contrast, RTI resistance-associated mutations were only sporadically detected in samples derived from drug-naive and RTIs-treated patients, except for the continuous appearance of two mutations in samples derived from two drug-naive patients. Our results demonstrate that many PI resistance-associated mutations and only a few RTI resistance-associated mutations continuously appear in CRF01_AE viruses derived from PI-naïve patients residing in northern Thailand.
Subject(s)
HIV Infections/virology , HIV Protease/genetics , HIV Reverse Transcriptase/genetics , HIV-1/genetics , Mutation , CD4 Lymphocyte Count , Drug Resistance, Viral , HIV-1/isolation & purification , Humans , Molecular Sequence Data , Polymerase Chain Reaction , Sequence Analysis, DNA , Thailand , Viral LoadABSTRACT
Recombinant human immunodeficiency virus type 1 (HIV-1) containing a CRF01_AE Gag, AE-Gag62, was significantly less susceptible to protease inhibitors (PIs) than the subtype B reference strain, NL4-3; therefore, the mechanism of how AE-Gag62 reduced viral drug susceptibility to PIs was studied in this report. The results showed that the lysine residue at amino acid position 165 (K165) of AE-Gag62 played a role in reducing the drug susceptibility of the recombinant virus to PIs. In addition, K165 potentially appears more frequently in CRF01_AE viruses than in the viruses of other major HIV-1 subtypes. Although K165 had no effect on the extent of recombinant protease-mediated in vitro Gag cleavage, it enhanced the incorporation of the Gag-Pol precursor protein, p160, into virions. Taken together, these results suggest that K165 of CRF01_AE Gag affects the regulation of virion assembly or maturation, and reduces viral drug susceptibility to PIs.
Subject(s)
Anti-HIV Agents/pharmacology , Drug Resistance, Multiple, Viral/genetics , HIV-1/drug effects , Lysine , Protease Inhibitors/pharmacology , gag Gene Products, Human Immunodeficiency Virus/metabolism , Amino Acid Sequence , Cell Line , Gene Expression Regulation, Viral/physiology , HIV-1/genetics , HIV-1/metabolism , Humans , Molecular Sequence Data , Recombinant Proteins , gag Gene Products, Human Immunodeficiency Virus/chemistry , gag Gene Products, Human Immunodeficiency Virus/geneticsABSTRACT
Two alpha-helical heptad repeats, N-HR and C-HR, located in the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein gp41, play an important role in membrane fusion by forming a 6-helix bundle. C34, a peptide mimicking C-HR, inhibits the formation of the 6-helix bundle; thus, it has potential as a novel antiretroviral compound. In order to improve the inhibitory effect of C34 on HIV-1 replication, we designed new C34-derived peptides based on computational analysis of the stable conformation of the 6-helix bundle. Newly designed peptides showed a stronger inhibitory effect on the replication of recombinant viruses containing CRF01_AE, subtype B or subtype C Env than C34 or a fusion inhibitor, T-20. In addition, these peptides inhibited the replication of a T-20-resistant virus. We propose that these peptides could be applied to develop novel antiretroviral compounds to inhibit the replication of various subtypes of HIV-1 as well as of T-20-resistant variants.
