RESUMO
The Plasmodium falciparum proteasome is a potential antimalarial drug target. We have identified a series of amino-amide boronates that are potent and specific inhibitors of the P. falciparum 20S proteasome (Pf20S) ß5 active site and that exhibit fast-acting antimalarial activity. They selectively inhibit the growth of P. falciparum compared with a human cell line and exhibit high potency against field isolates of P. falciparum and Plasmodium vivax They have a low propensity for development of resistance and possess liver stage and transmission-blocking activity. Exemplar compounds, MPI-5 and MPI-13, show potent activity against P. falciparum infections in a SCID mouse model with an oral dosing regimen that is well tolerated. We show that MPI-5 binds more strongly to Pf20S than to human constitutive 20S (Hs20Sc). Comparison of the cryo-electron microscopy (EM) structures of Pf20S and Hs20Sc in complex with MPI-5 and Pf20S in complex with the clinically used anti-cancer agent, bortezomib, reveal differences in binding modes that help to explain the selectivity. Together, this work provides insights into the 20S proteasome in P. falciparum, underpinning the design of potent and selective antimalarial proteasome inhibitors.
Assuntos
Compostos de Boro/farmacologia , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Complexo de Endopeptidases do Proteassoma/química , Inibidores de Proteassoma/farmacologia , Administração Oral , Animais , Compostos de Boro/administração & dosagem , Compostos de Boro/química , Domínio Catalítico , Humanos , Malária Falciparum/enzimologia , Malária Falciparum/parasitologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Modelos Moleculares , Plasmodium falciparum/enzimologia , Inibidores de Proteassoma/administração & dosagem , Inibidores de Proteassoma/químicaRESUMO
BACKGROUND: Recurrent vulvovaginal candidiasis affects nearly 138 million women globally each year. In the United States, fluconazole is considered the standard of care for acute vulvovaginal candidiasis, but until recently there was no US Food and Drug Administration-approved drug for the treatment of recurrent vulvovaginal candidiasis. Oteseconazole is a novel oral selective inhibitor of fungal lanosterol demethylase (sterol 14α-demethylase cytochrome P450, an enzyme required for fungal growth) approved for the treatment of recurrent vulvovaginal candidiasis. OBJECTIVE: This study was conducted to evaluate the efficacy and safety of oral oteseconazole (VT-1161) in the prevention of recurrent culture-verified acute vulvovaginal candidiasis episodes through 50 weeks in participants with recurrent vulvovaginal candidiasis and to compare the efficacy of oteseconazole and fluconazole in the treatment of the presenting acute vulvovaginal candidiasis episode. STUDY DESIGN: Women and postmenarcheal girls aged ≥12 years with a history of recurrent vulvovaginal candidiasis (N=219) were enrolled at 38 US sites. Eligible participants presenting with an active vulvovaginal candidiasis infection entered an induction phase in which they were randomly assigned 2:1 to receive 600 mg oral oteseconazole on day 1 and 450 mg on day 2, with matching placebo capsules, or to 3 sequential 150-mg oral doses (once every 72 hours) of fluconazole, with matching placebo capsules. Following the 2-week induction phase, the 185 participants with resolved acute vulvovaginal candidiasis infection (a clinical signs and symptoms score of <3) entered the maintenance phase and received 150 mg of oteseconazole or placebo weekly for 11 weeks. Participants were observed for an additional 37 weeks. RESULTS: In the induction phase, oteseconazole was noninferior to fluconazole in the proportion of participants in the intent-to-treat population with resolved acute vulvovaginal candidiasis infection at the week 2 (day 14) test-of-cure visit, with 93.2% of participants on oteseconazole vs 95.8% on fluconazole achieving resolution. In the maintenance phase, oteseconazole was superior to placebo in the proportion of participants in the intent-to-treat population with ≥1 culture-verified acute vulvovaginal candidiasis episode through 50 weeks, 5.1% compared with 42.2%, respectively (P<.001). Overall, treatment-emergent adverse event rates were similar in both groups: 54% for participants who received oteseconazole in the induction and maintenance phases vs 64% for participants who received fluconazole in the induction phase and placebo in the maintenance phase. Most treatment-emergent adverse events in each group were mild or moderate, with 3.4% of treatment-emergent adverse events graded as severe or higher in the OTESECONAZOLE/oteseconazole group vs 4.2% in FLUCONAZOLE/placebo group. CONCLUSION: In participants with recurrent vulvovaginal candidiasis, oteseconazole was safe and efficacious in the treatment and prevention of recurrent acute vulvovaginal candidiasis episodes and was noninferior to vulvovaginal candidiasis standard-of-care fluconazole in the treatment of the presenting acute vulvovaginal candidiasis infection.
Assuntos
Candidíase Vulvovaginal , Infecções , Feminino , Humanos , Candidíase Vulvovaginal/tratamento farmacológico , Candidíase Vulvovaginal/induzido quimicamente , Fluconazol/uso terapêutico , Fluconazol/efeitos adversos , Administração Oral , Antifúngicos/efeitos adversosRESUMO
Visceral leishmaniasis (VL), caused by the protozoan parasites Leishmania donovani and Leishmania infantum, is one of the major parasitic diseases worldwide. There is an urgent need for new drugs to treat VL, because current therapies are unfit for purpose in a resource-poor setting. Here, we describe the development of a preclinical drug candidate, GSK3494245/DDD01305143/compound 8, with potential to treat this neglected tropical disease. The compound series was discovered by repurposing hits from a screen against the related parasite Trypanosoma cruzi Subsequent optimization of the chemical series resulted in the development of a potent cidal compound with activity against a range of clinically relevant L. donovani and L. infantum isolates. Compound 8 demonstrates promising pharmacokinetic properties and impressive in vivo efficacy in our mouse model of infection comparable with those of the current oral antileishmanial miltefosine. Detailed mode of action studies confirm that this compound acts principally by inhibition of the chymotrypsin-like activity catalyzed by the ß5 subunit of the L. donovani proteasome. High-resolution cryo-EM structures of apo and compound 8-bound Leishmania tarentolae 20S proteasome reveal a previously undiscovered inhibitor site that lies between the ß4 and ß5 proteasome subunits. This induced pocket exploits ß4 residues that are divergent between humans and kinetoplastid parasites and is consistent with all of our experimental and mutagenesis data. As a result of these comprehensive studies and due to a favorable developability and safety profile, compound 8 is being advanced toward human clinical trials.
Assuntos
Antiprotozoários/administração & dosagem , Leishmania donovani/efeitos dos fármacos , Leishmania infantum/efeitos dos fármacos , Leishmaniose Visceral/diagnóstico por imagem , Inibidores de Proteassoma/administração & dosagem , Proteínas de Protozoários/antagonistas & inibidores , Animais , Antiprotozoários/química , Sítios de Ligação , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Humanos , Leishmania donovani/química , Leishmania donovani/enzimologia , Leishmania infantum/química , Leishmania infantum/enzimologia , Leishmaniose Visceral/parasitologia , Masculino , Camundongos , Complexo de Endopeptidases do Proteassoma/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Inibidores de Proteassoma/química , Conformação Proteica , Proteínas de Protozoários/química , Proteínas de Protozoários/metabolismoRESUMO
BACKGROUND: Acute vulvovaginal candidiasis (VVC) is common among women, but current azole antifungal treatments are often associated with safety and resistance issues. VT-1161 (oteseconazole) is an oral agent with increased selectivity for fungal CYP51. In this phase 2 clinical study, we evaluated the efficacy and safety of VT-1161 vs fluconazole in participants with moderate to severe acute VVC. METHODS: Participants presenting with an acute episode of VVC (nâ =â 55) were randomized to receive VT-1161 300 mg once daily (q.d.) for 3 days, 600 mg q.d. for 3 days, or 600 mg twice daily (b.i.d.) for 3 days or to receive a single dose of fluconazole 150 mg (FDA-approved dose to treat acute VVC). Participants were followed for 6 months. The primary outcome was the proportion of participants with therapeutic (clinical and mycological) cure at day 28. RESULTS: A larger proportion of participants in the per-protocol population experienced therapeutic cure in the VT-1161 300 mg q.d. (75.0%), VT-1161 600 mg q.d. (85.7%), and VT-1161 600 mg b.i.d. (78.6%) groups vs the fluconazole group (62.5%); differences were not statistically significant. At 3 and 6 months, no participants in the VT-1161 groups vs 28.5% and 46.1% in the fluconazole group, respectively, had evidence of mycological recurrence. No serious adverse events or treatment-emergent adverse events leading to discontinuation were reported. CONCLUSIONS: The majority of participants across all treatment groups achieved therapeutic cure at day 28. VT-1161 was well tolerated at all dose levels through 6 months of follow-up. CLINICAL TRIALS REGISTRATION: NCT01891331.
Assuntos
Candidíase Vulvovaginal , Administração Oral , Antifúngicos/uso terapêutico , Candidíase Vulvovaginal/tratamento farmacológico , Feminino , Fluconazol/uso terapêutico , Humanos , Piridinas/uso terapêutico , Tetrazóis/uso terapêuticoRESUMO
Malaria is a devastating parasitic disease caused by parasites from the genus Plasmodium. Therapeutic resistance has been reported against all clinically available antimalarials, threatening our ability to control the disease and therefore there is an ongoing need for the development of novel antimalarials. Towards this goal, we identified the 2-(N-phenyl carboxamide) triazolopyrimidine class from a high throughput screen of the Janssen Jumpstarter library against the asexual stages of the P. falciparum parasite. Here we describe the structure activity relationship of the identified class and the optimisation of asexual stage activity while maintaining selectivity against the human HepG2 cell line. The most potent analogues from this study were shown to exhibit equipotent activity against P. falciparum multidrug resistant strains and P. knowlesi asexual parasites. Asexual stage phenotyping studies determined the triazolopyrimidine class arrests parasites at the trophozoite stage, but it is likely these parasites are still metabolically active until the second asexual cycle, and thus have a moderate to slow onset of action. Non-NADPH dependent degradation of the central carboxamide and low aqueous solubility was observed in in vitro ADME profiling. A significant challenge remains to correct these liabilities for further advancement of the 2-(N-phenyl carboxamide) triazolopyrimidine scaffold as a potential moderate to slow acting partner in a curative or prophylactic antimalarial treatment.
Assuntos
Antimaláricos/farmacologia , Eritrócitos/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Plasmodium knowlesi/efeitos dos fármacos , Purinas/farmacologia , Antimaláricos/síntese química , Antimaláricos/química , Relação Dose-Resposta a Droga , Eritrócitos/parasitologia , Humanos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Purinas/síntese química , Purinas/química , Relação Estrutura-AtividadeRESUMO
Zeolite and zeolite-like molecular sieves are being used in a large number of applications such as adsorption and catalysis. Achievement of the long-standing goal of creating a chiral, polycrystalline molecular sieve with bulk enantioenrichment would enable these materials to perform enantioselective functions. Here, we report the synthesis of enantiomerically enriched samples of a molecular sieve. Enantiopure organic structure directing agents are designed with the assistance of computational methods and used to synthesize enantioenriched, polycrystalline molecular sieve samples of either enantiomer. Computational results correctly predicted which enantiomer is obtained, and enantiomeric enrichment is proven by high-resolution transmission electron microscopy. The enantioenriched and racemic samples of the molecular sieves are tested as adsorbents and heterogeneous catalysts. The enantioenriched molecular sieves show enantioselectivity for the ring opening reaction of epoxides and enantioselective adsorption of 2-butanol (the R enantiomer of the molecular sieve shows opposite and approximately equal enantioselectivity compared with the S enantiomer of the molecular sieve, whereas the racemic sample of the molecular sieve shows no enantioselectivity).
RESUMO
VT-1129 is a novel fungal enzyme-specific Cyp51 inhibitor with potent cryptococcal activity. Because of its long half-life (>6 days in mice) and our desire to quickly reach potent efficacy, we evaluated a VT-1129 loading dose-maintenance dose strategy against cryptococcal meningitis. VT-1129 plasma and brain pharmacokinetics were first studied in healthy mice, and these data were used to model loading dose-maintenance dose regimens to generate different steady-state concentrations. Mice were inoculated intracranially with Cryptococcus neoformans, and oral treatment began 1 day later. Treatment consisted of placebo or one of three VT-1129 loading dose-maintenance dose regimens, i.e., loading dose of 1, 3, or 30 mg/kg on day 1, followed by once-daily maintenance doses of 0.15, 0.5, or 5 mg/kg, respectively. In the fungal burden arm, therapy continued for 14 days and brains were collected on day 15 for fungal burden assessments. In the survival arm, treatment continued for 10 days, after which mice were monitored without therapy until day 30. VT-1129 plasma and brain concentrations were also measured. All VT-1129 doses significantly improved survival and reduced fungal burdens, compared to placebo. VT-1129 plasma and brain levels correlated with fungal burden reductions (R2 = 0.72 and R2 = 0.67, respectively), with a plasma concentration of 1 µg/ml yielding a reduction of â¼5 log10 CFU/g. With the highest loading dose-maintenance dose regimen, fungal burdens were undetectable in one-half of the mice in the fungal burden arm and in one-fourth of the mice in the survival arm, 20 days after the final dose. These data support a loading dose-maintenance dose strategy for quickly reaching highly efficacious VT-1129 concentrations for treating cryptococcal meningitis.
Assuntos
Antifúngicos/farmacologia , Meningite Criptocócica/tratamento farmacológico , Piridinas/farmacologia , Tetrazóis/farmacologia , Animais , Encéfalo/microbiologia , Cryptococcus neoformans/efeitos dos fármacos , Masculino , Meningite Criptocócica/microbiologia , Camundongos , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana/métodosRESUMO
Cryptococcal meningitis is a significant cause of morbidity and mortality in immunocompromised patients. VT-1129 is a novel fungus-specific Cyp51 inhibitor with potent in vitro activity against Cryptococcus species. Our objective was to evaluate the in vivo efficacy of VT-1129 against cryptococcal meningitis. Mice were inoculated intracranially with Cryptococcus neoformans Oral treatment with VT-1129, fluconazole, or placebo began 1 day later and continued for either 7 or 14 days, and brains and plasma were collected on day 8 or 15, 1 day after therapy ended, and the fungal burden was assessed. In the survival study, treatment continued until day 10 or day 28, after which mice were monitored off therapy until day 30 or day 60, respectively, to assess survival. The fungal burden was also assessed in the survival arm. VT-1129 plasma and brain concentrations were also measured. VT-1129 reached a significant maximal survival benefit (100%) at a dose of 20 mg/kg of body weight once daily. VT-1129 at doses of ≥0.3 mg/kg/day and each dose of fluconazole significantly reduced the brain tissue fungal burden compared to that in the control after both 7 and 14 days of dosing. The fungal burden was also undetectable in most mice treated with a dose of ≥3 mg/kg/day, even ≥20 days after dosing had stopped, in the survival arm. In contrast, rebounds in fungal burden were observed with fluconazole. These results are consistent with the VT-1129 concentrations, which remained elevated long after dosing had stopped. These data demonstrate the potential utility of VT-1129 to have a marked impact in the treatment of cryptococcal meningitis.
Assuntos
Inibidores de 14-alfa Desmetilase/farmacologia , Cryptococcus neoformans/efeitos dos fármacos , Meningite Criptocócica/tratamento farmacológico , Piridinas/farmacologia , Esterol 14-Desmetilase/metabolismo , Tetrazóis/farmacologia , Animais , Antifúngicos/farmacologia , Criptococose/tratamento farmacológico , Fluconazol/farmacologia , Camundongos , Testes de Sensibilidade Microbiana/métodos , Modelos TeóricosRESUMO
BACKGROUND: Lanosterol demethylase is an enzyme that is essential for fungal growth and catalyzes an early step in the biosynthetic pathway of ergosterol, which is a sterol that is required for fungal cell membrane formation and integrity. Lanosterol demethylase is the molecular target of the class of drugs referred to as "azole antifungals." VT-1161 is a novel, oral, selective inhibitor of fungal lanosterol demethylase and is being developed for the treatment of recurrent vulvovaginal candidiasis. OBJECTIVE: We evaluated the efficacy and safety of 4 dosing regimens of oral VT-1161 compared with placebo in women with recurrent vulvovaginal candidiasis, which was defined as at least 3 symptomatic episodes of acute vulvovaginal candidiasis within a 12-month period. STUDY DESIGN: Two hundred fifteen women with a documented history of recurrent vulvovaginal candidiasis and who, at screening, were experiencing an episode of acute vulvovaginal candidiasis (acute vulvovaginal candidiasis; composite vulvovaginal signs and symptoms score of ≥3 and a positive potassium hydroxide test for yeast) were enrolled. After treatment of the acute infection with fluconazole, subjects were assigned randomly to 1 of 5 treatment regimens: (1) VT-1161 150 mg once daily for 7 days, then 150 mg once weekly for 11 weeks, followed by a once-weekly dose of placebo for 12 weeks; (2) VT-1161 300 mg once daily for 7 days, then 300 mg once weekly for 11 weeks, followed by a once-weekly dose of placebo for 12 weeks; (3) VT-1161 150 mg once daily for 7 days, then 150 mg once weekly for 23 weeks; (4) VT-1161 300 mg once daily for 7 days, then 300 mg once weekly for 23 weeks; or (5) a matching placebo regimen for 24 weeks. The primary efficacy outcome was the proportion of subjects with ≥1 culture-verified acute vulvovaginal candidiasis episodes through week 48. RESULTS: In the intent-to-treat population, the proportion of subjects with ≥1 acute vulvovaginal candidiasis episodes ranged from 0-7% across the 4 VT-1161 arms vs 52% in the placebo arm, with all arms achieving statistical significance vs placebo. VT-1161 was well-tolerated with a favorable safety profile, and the incidence of adverse events was lower in all VT-1161 arms compared with placebo. In addition, no patient in any VT-1161 arm discontinued the study early because of an adverse event or laboratory abnormality. There was also no evidence of an adverse effect of VT-1161 on liver function or electrocardiogram recordings. CONCLUSION: In this study, VT-1161 was shown to be efficacious and safe in the treatment of patients with recurrent vulvovaginal candidiasis. These data strongly support further clinical investigation of VT-1161 for the treatment of recurrent vulvovaginal candidiasis.
Assuntos
Inibidores de 14-alfa Desmetilase/administração & dosagem , Antifúngicos/administração & dosagem , Candidíase Vulvovaginal/tratamento farmacológico , Piridinas/administração & dosagem , Tetrazóis/administração & dosagem , Administração Oral , Adulto , Antifúngicos/uso terapêutico , Método Duplo-Cego , Feminino , Fluconazol/uso terapêutico , Humanos , Quimioterapia de Indução , Quimioterapia de Manutenção , Pessoa de Meia-Idade , Recidiva , Adulto JovemRESUMO
Thein vitroactivities of the novel fungal Cyp51 inhibitor VT-1129 were evaluated against a large panel ofCryptococcus neoformansandCryptococcus gattiiisolates. VT-1129 demonstrated potent activities against bothCryptococcusspecies as demonstrated by low MIC50and MIC90values. ForC. gattii, thein vitropotency was maintained against all genotypes. In addition, significantly lower geometric mean MICs were observed for VT-1129 than for fluconazole againstC. neoformans, including isolates with reduced fluconazole susceptibility.
Assuntos
Inibidores de 14-alfa Desmetilase/farmacologia , Antifúngicos/farmacologia , Drogas em Investigação/farmacologia , Proteínas Fúngicas/antagonistas & inibidores , Piridinas/farmacologia , Esterol 14-Desmetilase/metabolismo , Tetrazóis/farmacologia , Inibidores de 14-alfa Desmetilase/síntese química , Antifúngicos/síntese química , Cryptococcus gattii/efeitos dos fármacos , Cryptococcus gattii/enzimologia , Cryptococcus gattii/genética , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/enzimologia , Cryptococcus neoformans/genética , Farmacorresistência Fúngica/genética , Drogas em Investigação/síntese química , Fluconazol/farmacologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Expressão Gênica , Genótipo , Testes de Sensibilidade Microbiana , Piridinas/síntese química , Esterol 14-Desmetilase/genética , Tetrazóis/síntese químicaRESUMO
Large-pore microporous materials are of great interest to process bulky hydrocarbon and biomass-derived molecules. ITQ-27 (IWV) has a two-dimensional pore system bounded by 12-membered rings (MRs) that lead to internal cross-sections containing 14 MRs. Investigations into the catalytic behavior of aluminosilicate (zeolite) materials with this framework structure have been limited until now due to barriers in synthesis. The facile synthesis of aluminosilicate IWV in both hydroxide and fluoride media is reported herein using simple, diquaternary organic structure-directing agents (OSDAs) that are based on tetramethylimidazole. In hydroxide media, a zeolite product with Si/Al=14.8-23.2 is obtained, while in fluoride media an aluminosilicate product with Si/Al up to 82 is synthesized. The material produced in hydroxide media is tested for the hydroisomerization of n-hexane, and results from this test reaction suggest that the effective pore size of zeolites with the IWV framework structure is similar to but slightly larger than that of ZSM-12 (MTW), in fairly good agreement with crystallographic data.
RESUMO
African sleeping sickness or human African trypanosomiasis, caused by Trypanosoma brucei spp., is responsible for approximately 30,000 deaths each year. Available treatments for this disease are poor, with unacceptable efficacy and safety profiles, particularly in the late stage of the disease when the parasite has infected the central nervous system. Here we report the validation of a molecular target and the discovery of associated lead compounds with the potential to address this lack of suitable treatments. Inhibition of this target-T. brucei N-myristoyltransferase-leads to rapid killing of trypanosomes both in vitro and in vivo and cures trypanosomiasis in mice. These high-affinity inhibitors bind into the peptide substrate pocket of the enzyme and inhibit protein N-myristoylation in trypanosomes. The compounds identified have promising pharmaceutical properties and represent an opportunity to develop oral drugs to treat this devastating disease. Our studies validate T. brucei N-myristoyltransferase as a promising therapeutic target for human African trypanosomiasis.
Assuntos
Aciltransferases/antagonistas & inibidores , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Trypanosoma brucei brucei/efeitos dos fármacos , Trypanosoma brucei brucei/enzimologia , Tripanossomíase Africana/tratamento farmacológico , Tripanossomíase Africana/parasitologia , Aciltransferases/metabolismo , Aminopiridinas/química , Aminopiridinas/metabolismo , Aminopiridinas/farmacologia , Aminopiridinas/uso terapêutico , Animais , Antiparasitários/química , Antiparasitários/metabolismo , Ensaios Enzimáticos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Humanos , Camundongos , Estrutura Molecular , Pirazóis/química , Pirazóis/metabolismo , Pirazóis/farmacologia , Pirazóis/uso terapêutico , Ratos , Sulfonamidas/química , Sulfonamidas/metabolismo , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Fatores de Tempo , Trypanosoma brucei brucei/crescimento & desenvolvimentoRESUMO
BACKGROUND: Pain in the hallux metatarsophalangeal joint (MTPJ) is very common, yet the underlying etiology remains unknown. Previous clinical research and biomechanical research has implicated stenosing flexor hallucis longus (FHL) tendonitis as a possible cause. The hypothesis of this study was that treatment solely focusing on alleviating restricted FHL excursion would be beneficial in patients with hallux MTPJ pain. METHODS: This is a retrospective study of those treated in the Foot & Ankle Division between January 2009, and December 2018, who were diagnosed with FHL tendonitis with associated pain in the hallux MTPJ. Demographics, comorbidities, examination findings, imaging results, pain scores, treatment instituted, and outcome was obtained from the electronic medical record. The primary outcome was the improvement in the pain score (visual analog scale [VAS]). The surgical patients were included if their procedure was solely related to the FHL (posteromedial ankle release ± os trigonum resection). The decision to have surgery was analyzed by univariate and multivariable statistics using demographics, comorbidities, and clinical findings as potential factors (P < .05). RESULTS: In 75% (59 of 79 feet), nonoperative treatment of FHL stenosis resulted in a decrease in pain scores that the patients felt was satisfactory. The operative group that had an FHL release showed decreased pain in 90% (18 of 20 feet). Multivariable analysis identified the need for immobilization (OR 9.8, 95% CI 1.8-55.2, P = .009), participating in athletics (OR 8.7, 95% CI 1.8-42.2, P = .007), and higher initial VAS (OR 1.7, 95% CI 1.3-2.3, P < .001) as being associated with the decision for surgery. CONCLUSION: Previous biomechanical studies have suggested that stenosing FHL synovitis can cause increased intraarticular loading in the hallux MTPJ. The current clinical study supports this hypothesis, demonstrating that treatment focused on relieving restricted FHL excursion can ameliorate pain in the hallux MTPJ in select cases.
RESUMO
Malaria is a devastating disease that causes significant morbidity worldwide. The development of new antimalarial chemotypes is urgently needed because of the emergence of resistance to frontline therapies. Independent phenotypic screening campaigns against the Plasmodium asexual parasite, including our own, identified the aryl amino acetamide hit scaffold. In a prior study, we identified the STAR-related lipid transfer protein (PfSTART1) as the molecular target of this antimalarial chemotype. In this study, we combined structural elements from the different aryl acetamide hit subtypes and explored the structure-activity relationship. It was shown that the inclusion of an endocyclic nitrogen, to generate the tool compound WJM-715, improved aqueous solubility and modestly improved metabolic stability in rat hepatocytes. Metabolic stability in human liver microsomes remains a challenge for future development of the aryl acetamide class, which was underscored by modest systemic exposure and a short half-life in mice. The optimized aryl acetamide analogs were cross resistant to parasites with mutations in PfSTART1, but not to other drug-resistant mutations, and showed potent binding to recombinant PfSTART1 by biophysical analysis, further supporting PfSTART1 as the likely molecular target. The optimized aryl acetamide analogue, WJM-715 will be a useful tool for further investigating the druggability of PfSTART1 across the lifecycle of the malaria parasite.
Assuntos
Antimaláricos , Proteínas de Transporte , Malária Falciparum , Malária , Ratos , Camundongos , Humanos , Animais , Antimaláricos/química , Plasmodium falciparum , Malária Falciparum/tratamento farmacológico , Malária/tratamento farmacológico , Acetamidas/farmacologia , LipídeosRESUMO
Emerging resistance to current antimalarials is reducing their effectiveness and therefore there is a need to develop new antimalarial therapies. Toward this goal, high throughput screens against the P. falciparum asexual parasite identified the pyrazolopyridine 4-carboxamide scaffold. Structure-activity relationship analysis of this chemotype defined that the N1-tert-butyl group and aliphatic foliage in the 3- and 6-positions were necessary for activity, while the inclusion of a 7'-aza-benzomorpholine on the 4-carboxamide motif resulted in potent anti-parasitic activity and increased aqueous solubility. A previous report that resistance to the pyrazolopyridine class is associated with the ABCI3 transporter was confirmed, with pyrazolopyridine 4-carboxamides showing an increase in potency against parasites when the ABCI3 transporter was knocked down. The low metabolic stability intrinsic to the pyrazolopyridine scaffold and the slow rate by which the compounds kill asexual parasites resulted in poor performance in a P. berghei asexual blood stage mouse model. Lowering the risk of resistance and mitigating the metabolic stability and cytochrome P450 inhibition will be challenges in the future development of the pyrazolopyrimidine antimalarial class.
Assuntos
Antimaláricos , Plasmodium falciparum , Pirazóis , Piridinas , Antimaláricos/farmacologia , Antimaláricos/química , Antimaláricos/síntese química , Plasmodium falciparum/efeitos dos fármacos , Relação Estrutura-Atividade , Pirazóis/química , Pirazóis/farmacologia , Pirazóis/síntese química , Animais , Piridinas/farmacologia , Piridinas/química , Piridinas/síntese química , Camundongos , Testes de Sensibilidade Parasitária , Estrutura Molecular , Resistência a Medicamentos/efeitos dos fármacos , Relação Dose-Resposta a Droga , HumanosRESUMO
To contribute to the global effort to develop new antimalarial therapies, we previously disclosed initial findings on the optimization of the dihydroquinazolinone-3-carboxamide class that targets PfATP4. Here we report on refining the aqueous solubility and metabolic stability to improve the pharmacokinetic profile and consequently in vivo efficacy. We show that the incorporation of heterocycle systems in the 8-position of the scaffold was found to provide the greatest attainable balance between parasite activity, aqueous solubility, and metabolic stability. Optimized analogs, including the frontrunner compound S-WJM992, were shown to inhibit PfATP4-associated Na+-ATPase activity, gave rise to a metabolic signature consistent with PfATP4 inhibition, and displayed altered activities against parasites with mutations in PfATP4. Finally, S-WJM992 showed appreciable efficacy in a malaria mouse model and blocked gamete development preventing transmission to mosquitoes. Importantly, further optimization of the dihydroquinazolinone class is required to deliver a candidate with improved pharmacokinetic and risk of resistance profiles.
RESUMO
There is an urgent need to populate the antimalarial clinical portfolio with new candidates because of resistance against frontline antimalarials. To discover new antimalarial chemotypes, we performed a high-throughput screen of the Janssen Jumpstarter library against the Plasmodium falciparum asexual blood-stage parasite and identified the 2,3-dihydroquinazolinone-3-carboxamide scaffold. We defined the SAR and found that 8-substitution on the tricyclic ring system and 3-substitution of the exocyclic arene produced analogues with potent activity against asexual parasites equivalent to clinically used antimalarials. Resistance selection and profiling against drug-resistant parasite strains revealed that this antimalarial chemotype targets PfATP4. Dihydroquinazolinone analogues were shown to disrupt parasite Na+ homeostasis and affect parasite pH, exhibited a fast-to-moderate rate of asexual kill, and blocked gametogenesis, consistent with the phenotype of clinically used PfATP4 inhibitors. Finally, we observed that optimized frontrunner analogue WJM-921 demonstrates oral efficacy in a mouse model of malaria.
Assuntos
Antimaláricos , Malária Falciparum , Malária , Animais , Camundongos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Plasmodium falciparum , Homeostase , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologiaRESUMO
The development of new antimalarials is required because of the threat of resistance to current antimalarial therapies. To discover new antimalarial chemotypes, we screened the Janssen Jumpstarter library against the P. falciparum asexual parasite and identified the 7-N-substituted-3-oxadiazole quinolone hit class. We established the structure-activity relationship and optimized the antimalarial potency. The optimized analog WJM228 (17) showed robust metabolic stability in vitro, although the aqueous solubility was limited. Forward genetic resistance studies uncovered that WJM228 targets the Qo site of cytochrome b (cyt b), an important component of the mitochondrial electron transport chain (ETC) that is essential for pyrimidine biosynthesis and an established antimalarial target. Profiling against drug-resistant parasites confirmed that WJM228 confers resistance to the Qo site but not Qi site mutations, and in a biosensor assay, it was shown to impact the ETC via inhibition of cyt b. Consistent with other cyt b targeted antimalarials, WJM228 prevented pre-erythrocytic parasite and male gamete development and reduced asexual parasitemia in a P. berghei mouse model of malaria. Correcting the limited aqueous solubility and the high susceptibility to cyt b Qo site resistant parasites found in the clinic will be major obstacles in the future development of the 3-oxadiazole quinolone antimalarial class.
Assuntos
Antimaláricos , Antagonistas do Ácido Fólico , Malária Falciparum , Quinolonas , Animais , Camundongos , Antimaláricos/farmacologia , Citocromos b , Antagonistas do Ácido Fólico/metabolismo , Malária Falciparum/tratamento farmacológico , Malária Falciparum/parasitologia , Plasmodium falciparum , Quinolonas/farmacologiaRESUMO
BACKGROUND: Management of recurrent vulvovaginal candidiasis (RVVC) is an unmet clinical challenge without approved treatment in the United States. Oteseconazole is a novel oral selective inhibitor of fungal CYP51, designed to treat RVVC without off-target toxicities. VIOLET comprised two global, phase 3, multicenter, randomized, double-blind, placebo-controlled trials (CL-011 and CL-012). The primary objective was to evaluate oteseconazole efficacy through week 48. Key secondary objectives evaluated time to first recurrence, safety, and patient-reported outcomes. METHODS: Women with three or more symptomatic acute vulvovaginal candidiasis (VVC) episodes within the previous 12-month period, including the screening episode (in which the VVC episode cleared with fluconazole induction therapy), were randomly assigned 2:1 at baseline (maintenance phase) to 150 mg of oral oteseconazole daily for 7days and then once weekly for 11 weeks or to matching placebo for 12 weeks. Time-to-first-recurrence data were collected during the maintenance phase. Posttreatment follow-up was 36 weeks. RESULTS: Among 656 women (326 in CL-011 and 330 in CL-012), the averaged percentage of participants with one or more RVVC episodes through week 48 was 6.7% (range, 6.5 to 7.4%) in CL-011 and 3.9% (3.7 to 4.6%) in CL-012 in the oteseconazole groups versus 42.8% (41.3 to 45.0%) and 39.4% (38.0 to 42.6%) in the corresponding placebo groups (P<0.001). Among oteseconazole-treated participants in CL-011 and CL-012 who experienced an RVVC episode (n=22), the mean time to recurrence was 45.7 and 47.2 weeks versus 27.8 and 33.1 weeks for placebo-treated participants (n=84), respectively (hazard ratio [95% confidence interval], 0.11 [0.06 to 0.21] for CL-011 and 0.08 [0.04 to 0.17] for CL-012; P<0.001). Types and frequencies of treatment-emergent adverse events (TEAEs) were similar between groups in both trials, with no drug-related serious TEAEs or adverse effects on pregnancy outcomes, liver function, or QT interval. CONCLUSIONS: Oral oteseconazole was effective in preventing acute VVC recurrence and treating RVVC through week 48 in the CL-011 and CL-012 trials, with mostly mild TEAEs. (Funded by Mycovia Pharmaceuticals, Inc., ClinicalTrials.gov numbers, NCT03562156 for CL-011 and NCT03561701 for CL-012.)
Assuntos
Antifúngicos , Candidíase Vulvovaginal , Recidiva , Humanos , Feminino , Candidíase Vulvovaginal/tratamento farmacológico , Antifúngicos/uso terapêutico , Antifúngicos/efeitos adversos , Antifúngicos/administração & dosagem , Adulto , Método Duplo-Cego , Adulto Jovem , Resultado do Tratamento , Pessoa de Meia-Idade , AdolescenteRESUMO
Aminoacyl transfer RNA (tRNA) synthetases (aaRSs) are attractive drug targets, and we present class I and II aaRSs as previously unrecognized targets for adenosine 5'-monophosphate-mimicking nucleoside sulfamates. The target enzyme catalyzes the formation of an inhibitory amino acid-sulfamate conjugate through a reaction-hijacking mechanism. We identified adenosine 5'-sulfamate as a broad-specificity compound that hijacks a range of aaRSs and ML901 as a specific reagent a specific reagent that hijacks a single aaRS in the malaria parasite Plasmodium falciparum, namely tyrosine RS (PfYRS). ML901 exerts whole-life-cycle-killing activity with low nanomolar potency and single-dose efficacy in a mouse model of malaria. X-ray crystallographic studies of plasmodium and human YRSs reveal differential flexibility of a loop over the catalytic site that underpins differential susceptibility to reaction hijacking by ML901.