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1.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S11-S18, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32863156

ABSTRACT

OBJECTIVE: Multi-centre study of the National French Registry (EPIIC) of patients with cochlear implants, focusing on infants who were operated-on under the age of 24 months between 2012 and 2016. PATIENTS AND METHODS: A total of 615 profoundly deaf infants, who received cochlear implants (CIs) before their second birthday, were included in the registry by different CI centers. Epidemiological, surgical, speech therapy and school, follow-up data were included in the registry, 12, 24, 36 and 48 months thereafter. The following parameters were studied: type of implantation (uni- or bilateral), complications, cause of deafness, category of auditory perception (CAP), Open-set word recognition score (OSW), speech intelligibility rating, lexical comprehension with EVIP (Peabody), communication mode and type of schooling. Bilateral simultaneous CI (BiCI) and unilateral CI (UniCI) groups were compared. RESULTS: There were 744 implantations. The explantation-reimplantation rate, within the four-year follow-up, was just 3.6%. Mean implantation age was 16.0 months, and similar in the two groups (BiCI/UniCI). A total of 51% of children had their first implant between 12 and 18 months, and 15% before 12 months. Implantation was unilateral in 52% of cases. Fifty-six percent of the bilateral procedures were sequential, with a mean delay of 16.8 months for the second implantation. The cause of deafness was unknown in 52% of cases. Of the 48% (297/615) of attributed cases, 32% had clear genetic causes. The remaining deafness was due to cytomegalovirus (CMV, 8%), inner-ear malformation (5%) and meningitis (3%). The main complications were from infections (47%) and internal device failure (25%). Four years post-operation, 84% of the UniCI and 75% of BiCl groups had a CAP≥5, and 83% of UniCl and 100% BiCI had OSW≥80%. Furthermore 74% of UniCI and 77% of BiCI communicated orally and 85% of UniCI and 90% of BiCI integrated into mainstream schooling. CONCLUSION: The French Registry of cochlear implants (EPIIC) is the only such national registry in the world. Our analysis illustrates the immediate benefits of, either single or double, cochlear implantation for language, perception skills and schooling.


Subject(s)
Auditory Perception , Child Language , Cochlear Implantation/statistics & numerical data , Cochlear Implants/statistics & numerical data , Deafness/rehabilitation , Registries/statistics & numerical data , Age Factors , Cochlear Implantation/adverse effects , Cochlear Implantation/methods , Cochlear Implants/adverse effects , Communication , Correction of Hearing Impairment/instrumentation , Correction of Hearing Impairment/statistics & numerical data , Deafness/etiology , Device Removal/statistics & numerical data , Education of Hearing Disabled/methods , Education of Hearing Disabled/statistics & numerical data , Follow-Up Studies , France , Humans , Infant , Infant, Newborn , Mainstreaming, Education/statistics & numerical data , Reoperation/statistics & numerical data , Schools , Speech Intelligibility , Speech Therapy/statistics & numerical data , Time Factors
2.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S5-S9, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32891589

ABSTRACT

Cochlear and brainstem implants have been included on the list of reimbursable products (LPPR) in France since March of 2009. The implants were initially inscribed for 5 years, after which an application for renewal with the French National Commission for the Evaluation of Medical Devices and Health Technologies (Commission Nationale d'évaluation des dispositifs médicaux et des technologies de santé - CNEDiMTS) was required [Haute Autorité de santé, 2009]. Upon registration to the list of reimbursable products, the companies and the reference centers for cochlear and brainstem implants were asked to set up a post-registration registry called EPIIC. This article reports the evolution in the EPIIC registry of the general indicators for 5051 patients over the five years from 2012-2016.


Subject(s)
Auditory Brain Stem Implants/statistics & numerical data , Cochlear Implants/statistics & numerical data , Registries/statistics & numerical data , Advisory Committees/organization & administration , Age Factors , Aged , Aged, 80 and over , Auditory Brain Stem Implants/economics , Cochlear Implantation/statistics & numerical data , Cochlear Implants/economics , Computer Security , Databases as Topic , Device Approval/legislation & jurisprudence , Device Removal/statistics & numerical data , France , Guidelines as Topic/standards , Health Care Sector/economics , Health Care Sector/legislation & jurisprudence , Humans , Infant , Infant, Newborn , Insurance, Health, Reimbursement , Quality Control , Reference Standards , Time Factors
3.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S45-S49, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32826202

ABSTRACT

This study aims to determine the frequency and causes of cochlear explants with re-implantation (ERI) after 5 years' follow up of the patients included in the French national EPIIC (étude post-inscription des implants cochléaires) registry tracking patients with cochlear implantation. This multicenter, descriptive prospective study was conducted on 5051 patients enrolled in the EPIIC database between January 2012 and December 2016. Ninety-five patients (1.9%) received a primary implant and an ERI during the study. Of these, four benefitted from two ERIs. The number of ERIs was significantly higher in the pediatric population than among adults. The explantation and reimplantation were performed simultaneously in 86% of cases. The reasons for explantation were: in 46.4% of cases linked to a malfunction of the implant, and in 39.3% of cases for medical or surgical reasons. The number of electrodes inserted was significantly higher after the ERI than after the first implantation. There was just one post-ERI infection for these 95 explanted and re-implanted patients. As well as explantation with reimplantation rarely being necessary, it generally presents no major surgical difficulty and in most cases it allows a better integration than in the first implantation.


Subject(s)
Cochlear Implantation/statistics & numerical data , Cochlear Implants/statistics & numerical data , Device Removal/statistics & numerical data , Registries/statistics & numerical data , Reoperation/statistics & numerical data , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Child , Child, Preschool , Cochlear Implants/adverse effects , France , Humans , Infant , Middle Aged , Prospective Studies , Prosthesis Failure , Replantation/statistics & numerical data , Time Factors , Young Adult
4.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S57-S63, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32792302

ABSTRACT

This study concerns the results of cochlear implantation in children and adults from French cochlear implantation centers, monitored at one, two and three years by the Cochlear Implant French Registry EPIIC. This multicenter study enrolled 2603 subjects (1667 adults and 936 children) implanted in one ear. The following parameters were studied: hearing overall performances, monosyllabic or dissyllabic word perception, speech intelligibility, self-assessment questionnaire of Cochlear Implant (CI) benefits (Abbreviated profile of Hearing aid Benefit); professional activity and schooling. This study confirms the ceiling effect in adults' performances after the 1st year and the progressive growth in children's performances. It also shows that the contralateral hearing aid enhances performances compared to the CI alone condition, in all follow-up sessions. The French register of CIs is the only worldwide register of systematic follow-up on a period of three years and more of all adults and children implanted in a country.


Subject(s)
Cochlear Implantation/statistics & numerical data , Cochlear Implants/statistics & numerical data , Deafness/rehabilitation , Quality of Life , Registries/statistics & numerical data , Adolescent , Adult , Age Factors , Auditory Perception , Child , Child, Preschool , Education , Employment , Follow-Up Studies , France , Humans , Infant , Infant, Newborn , Self-Assessment , Speech Intelligibility , Surveys and Questionnaires , Time Factors , Treatment Outcome
5.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S19-S25, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32773333

ABSTRACT

OBJECTIVES: To analyze the performance of cochlear implants in French patients aged 65 and over, implanted between 2012 and 2016, using data from the French national registry for cochlear implants (EPIIC). MATERIALS AND METHODS: The French national registry incorporates patient data from before implantation and for three years after implantation, stratified in different age groups (18-39, 40-64years, 65-74years and>75years). Here, we assessed the latter two categories. Hearing was assessed using mono- and disyllabic words in a silent background. The Category of Auditory Performance (CAP) scale was also implemented and subjects took the Abbreviated Profile of Hearing Aid Benefit (Aphab) questionnaire. RESULTS: The population aged over 65 accounted for 38% (n=1193) of the 3178 adult implanted patients. The performance for mono- and disyllabic words in silence, the CAP scores and the APHAB questionnaire answers for ease of communication, background noise and reverberation were dramatically improved at one year post-implantation (P<0.0001 for each score) and remained stable between one and three years thereafter. The percentage improvement was similar across all age groups. The scores for loud-noise intolerance did not change after cochlear implantation in any age group. CONCLUSION: Cochlear implants improve hearing and communication in subjects aged 65 and over, with comparable efficiency to that achieved in younger subjects. Cochlear implantation should thus be proposed whenever hearing aids provide only limited benefit. However, between 2012 and 2016, cochlear implantation was given to less than 1% of the French population aged 65 and over with profound deafness.


Subject(s)
Cochlear Implantation/statistics & numerical data , Cochlear Implants/statistics & numerical data , Hearing Loss/rehabilitation , Registries/statistics & numerical data , Adult , Age Factors , Aged , Aged, 80 and over , Auditory Perception , Cochlear Implantation/methods , Communication , Female , France , Health Surveys , Hearing Loss/etiology , Hearing Tests/methods , Humans , Male , Middle Aged , Noise/adverse effects , Retrospective Studies , Time Factors , Young Adult
6.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S27-S35, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32763084

ABSTRACT

OBJECTIVE: Evaluate in France the outcomes of cochlear implantation outside the selection criteria, off-label. MATERIAL AND METHODS: This is a prospective cohort study including adults and children having received a cochlear implant (CI) in an off-label indication, that is outside the criteria established by the "Haute Autorité de santé (HAS)" in 2012. The data was collected from the "EPIIC" registry on recipients who received CIs in France between 2011 and 2014. Speech audiometry was performed at 60dB preimplantation and after one year of CI use, as well as an evaluation of the scores of the quality of life with the APHAB questionnaire, the scores for CAP and the professional/academic status in pre- and post-implantation conditions. Major and minor complications at surgery have been recorded. RESULTS: In total, 590 patients (447 adults and 143 children) with an off-label indication for CIs were included in this study from the EPIIC registry (11.7% of the whole cohort of EPIIC). For adults, the median percentage of comprehension using monosyllabic word lists was 41% in preimplantation condition versus 53% after one year of CI use (P<0.001) and 60% versus 71% in dissyllabic word lists (P<0.001). The CAP scores were 5 versus 6 in pre- and post-implantation conditions respectively (P<0.001) and the APHAB scores were statistically lower after implantation (P<0.001). In the children cohort, the median percentage of comprehension using monosyllabic word lists was 51% in preimplantation condition and 65% after CI (P<0.001), and 48% versus 82% (P<0.001) for dissyllabic word lists. The CAP scores were 5 versus 7 respectively in pre- and post-CI conditions (P<0.001). Thirty-two minor complications (5.4%) and 17 major complications (2.8%) were reported in our panel of off-label indication patients. CONCLUSION: These results suggest that a revision of the cochlear implantation candidacy criteria is necessary to allow more patients with severe or asymmetric hearing loss to benefit from a CI when there is an impact on quality of life despite the use of an optimal hearing aid.


Subject(s)
Auditory Brain Stem Implantation/statistics & numerical data , Cochlear Implantation/statistics & numerical data , Cochlear Implants/statistics & numerical data , Hearing Loss/rehabilitation , Patient Selection , Registries/statistics & numerical data , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Audiometry, Speech/methods , Child , Child, Preschool , Cochlear Implantation/adverse effects , Cochlear Implants/adverse effects , Female , France/epidemiology , Health Surveys , Humans , Male , Middle Aged , Off-Label Use/statistics & numerical data , Postoperative Complications/epidemiology , Postoperative Period , Preoperative Care , Prospective Studies , Quality of Life , Young Adult
7.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S51-S56, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32739279

ABSTRACT

OBJECTIVES: Assessment of the incidence and results of bilateral cochlear implantation in adults and children in France. MATERIALS AND METHODS: Multicenter retrospective study of data in the French national registry of cochlear implantations from January 1st 2012 to December 31st 2016. Functional results from CAP (Category of Auditory Performance) questionnaires and speech audiometry tests, with mono- and di-syllabic word-lists, were compared before and after implantation. Speech audiometry tests were carried out against a noisy background, except before simultaneous implantations. RESULTS: Nine hundred and forty two bilateral cochlear implantations were performed during this period, that is, 16.4% of all cochlear implantations. Five hundred and eighty eight bilateral implantations were performed sequentially. 59% of the bilateral implantations were performed in children. Bilateral implants significantly improved CAP scores in all cases (P<0.001). Auditory performance, with the two types of word-list, were significantly improved after simultaneous implantation (P<0.01). After sequential implantation, the speech discrimination score, already very good with the first implant, reached 63±26% [0-100] with monosyllabic word lists, and 72±28% [0-100] with dissyllabic words. There were more complications due to surgery in bilateral cases than in the entire population of cochlear recipients (9.1% vs 6.4%, P<0.02). CONCLUSION: Hearing is significantly improved by simultaneous cochlear implantation. For sequential implantation, at one year, when auditory results were already excellent from the first implant, in the bimodal condition CAP scores were significantly improved, although there was no further change in speech audiometry in noise.


Subject(s)
Cochlear Implantation/methods , Cochlear Implants/statistics & numerical data , Deafness/rehabilitation , Registries/statistics & numerical data , Adult , Audiometry, Speech/methods , Auditory Perception , Child , Cochlear Implantation/adverse effects , Cochlear Implantation/statistics & numerical data , Deafness/etiology , Female , France , Humans , Male , Postoperative Complications/epidemiology , Retrospective Studies , Speech Discrimination Tests/statistics & numerical data
8.
Eur Ann Otorhinolaryngol Head Neck Dis ; 137 Suppl 1: S37-S43, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32861600

ABSTRACT

OBJECTIVES: The aim of this study was to evaluate peri- and post-operative complications related to cochlear implantations. We searched for risk factors predicting these complications and analyzed the complications in the youngest and most elderly. STUDY DESIGN: Retrospective analysis of cochlear implant patients. MATERIALS AND METHODS: All patients who underwent cochlear implantation in France between January 2012 and December 2016 were anonymized and registered in the EPIIC database. This population included 3483 adults and 2245 children. Their demographic and surgical data and their incidence of peri- or post-operative complications, including their severity, whether major or minor, were all indicated. RESULTS: The global complication rate was 6.84%. The risk of complication was higher in initial implantation versus reimplantation (P<0.0001). The risk was also higher for bilateral implantation versus unilateral (P<0.0001). Complications were more frequent for patients with cochlear malformation (P=0.002). There was no difference in complication rates across age groups; babies under 1 year old, and the elderly over 80 and even over 90, did not have more complications than the rest of the population. Patients treated in the daily care unit had no more complications than those who were hospitalized for one night or more (P=0.64). CONCLUSION: Cochlear implantation is a safe technique with a low incidence of complications. The absence of increased risk in patients at the extremes of the age spectrum justifies offering this solution to all, without age limitation.


Subject(s)
Cochlear Implantation/adverse effects , Hearing Loss/rehabilitation , Intraoperative Complications/epidemiology , Postoperative Complications/epidemiology , Registries/statistics & numerical data , Adolescent , Adult , Age Factors , Aged , Aged, 80 and over , Child , Child, Preschool , Cochlea/abnormalities , Cochlear Implantation/methods , Day Care, Medical/statistics & numerical data , France/epidemiology , Hearing Loss/etiology , Hospitalization/statistics & numerical data , Humans , Incidence , Infant , Middle Aged , Reoperation/adverse effects , Reoperation/statistics & numerical data , Retrospective Studies , Risk Factors , Young Adult
9.
Eur Ann Otorhinolaryngol Head Neck Dis ; 136(4): 273-279, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31072727

ABSTRACT

OBJECTIVES: Fabry disease (FD) is an X-linked inherited lysosomal storage disease. It is a multisystem pathology that can include ENT disorders. The aim of the present study was to investigate the cochleovestibular manifestations of FD, in order to show the importance of screening and systematic ENT evaluation. MATERIAL AND METHODS: A single-center retrospective study included 14 male and 23 female FD patients. Hearing impairment was defined as hearing loss greater than the 90th percentile for at least one frequency. Vestibular impairment was defined by lateral semicircular canal dysfunction. Age, ongoing enzyme replacement therapy (ERT) and organic (renal, cardiac and cerebrovascular) complications were used as severity markers. RESULTS: Hearing impairment was found in 62.6% of cases, mostly at high frequencies, and was associated with age, ERT, and cardiac and cerebrovascular disorder. It affected 46.7% of asymptomatic adult patients. Vestibular impairment was found in 56% of cases, associated with age; it affected two-thirds of ERT patients, more than 60% of patients with organic complications, and 50% of asymptomatic adult patients. CONCLUSIONS: More than half of patients had ENT involvement. All FD patients should undergo early ENT screening for diagnostic, prognostic and therapeutic purposes. Systematic complete ENT follow-up with auditory and vestibular evaluation should be performed regularly, even for heterozygous women.


Subject(s)
Fabry Disease/complications , Adolescent , Adult , Age Factors , Aged , Auditory Threshold , Cardiovascular Diseases/complications , Child , Deafness/complications , Deafness/diagnosis , Enzyme Replacement Therapy , Fabry Disease/therapy , Female , Hearing Loss/complications , Hearing Loss/diagnosis , Humans , Ischemic Attack, Transient/complications , Male , Middle Aged , Nystagmus, Pathologic/complications , Nystagmus, Pathologic/diagnosis , Proteinuria/complications , Proteinuria/diagnosis , Renal Insufficiency/complications , Renal Insufficiency/diagnosis , Retrospective Studies , Stroke/complications , Tinnitus/complications , Tinnitus/diagnosis , Vertigo/complications , Vertigo/diagnosis , Young Adult
10.
Eur Ann Otorhinolaryngol Head Neck Dis ; 135(1): 63-65, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28760617

ABSTRACT

INTRODUCTION: Liposarcoma of the hypopharynx is extremely rare, as only 28 cases have been reported in the literature. The cardinal symptom of liposarcoma is progressively worsening dysphagia. CASE REPORT: The authors report the case of a 71-year-old man who presented with dysphagia, marked weight loss over several weeks and an episode of exteriorization of a solid mass from the mouth during an episode of vomiting. Imaging revealed a fat density intra-oesophageal mass. Panendoscopy and upper gastrointestinal endoscopy visualized the pedunculated tumour in the left piriform sinus, which was able to be exteriorized via the mouth. The tumour was then resected endoscopically at its hypopharyngeal insertion pedicle. Histological examination of the operative specimen concluded on well-differentiated benign liposarcoma. DISCUSSION: Well-differentiated liposarcoma is the most common form of liposarcoma, but is only exceptionally reported in the hypopharynx. The main symptoms are related to compression of adjacent structures. Imaging findings are nonspecific. Only histological examination can distinguish liposarcoma from other benign oesophageal tumours. Standard treatment consists of wide, complete resection, which is not always possible in the neck. Long-term follow-up of these patients is essential in order to rapidly detect recurrence.


Subject(s)
Hypopharyngeal Neoplasms/pathology , Hypopharyngeal Neoplasms/surgery , Laryngoscopy , Liposarcoma/pathology , Liposarcoma/surgery , Aged , Diagnosis, Differential , Humans , Laryngoscopy/methods , Male , Treatment Outcome
11.
Bioorg Med Chem Lett ; 11(17): 2319-23, 2001 Sep 03.
Article in English | MEDLINE | ID: mdl-11527723

ABSTRACT

The novel phosphotyrosine (pTyr) mimetic 4'-carboxymethyloxy-3'-phosphonophenylalanine (Cpp) has been designed and incorporated into a series of nonpeptide inhibitors of the SH2 domain of pp60(c-Src) (Src) tyrosine kinase. A 2.2 A X-ray crystal structure of 1a bound to a mutant form of Lck SH2 domain provides insight regarding the structure-activity relationships and supports the design concept of this new pTyr mimetic.


Subject(s)
Benzamides/chemistry , Benzamides/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Organophosphonates/chemistry , Organophosphonates/pharmacology , Phosphotyrosine/chemistry , Proto-Oncogene Proteins pp60(c-src)/antagonists & inhibitors , src Homology Domains/drug effects , Animals , Binding Sites , Bone Resorption , Crystallography, X-Ray , Dentin/drug effects , Drug Design , Enzyme Inhibitors/metabolism , Magnetic Resonance Spectroscopy , Molecular Mimicry , Mutation , Osteoclasts/drug effects , Osteoclasts/metabolism , Proto-Oncogene Proteins pp60(c-src)/chemistry , Proto-Oncogene Proteins pp60(c-src)/genetics , Rabbits , Structure-Activity Relationship
12.
J Comb Chem ; 2(4): 305-13, 2000.
Article in English | MEDLINE | ID: mdl-10891096

ABSTRACT

Using a novel, solid-phase parallel synthetic route and a computational docking program, a series of phosphorylated nonpeptides were generated to determine their structure-activity relationships (SAR) for binding at the SH2 domain of pp60src (Src). A functionalized benzoic acid intermediate was attached to solid support via Rink amide linkage, which upon acid cleavage generated the desired benzamide template-based nonpeptides in a facile manner. Compounds were synthesized using a combination of solid- and solution-phase techniques. Purification using reversed-phase, semipreparative HPLC allowed for quantitative SAR studies. Specifically, this work focused on functional group modifications, in a parallel fashion, designed to explore hydrophobic binding at the pY+3 pocket of the Src SH2 domain.


Subject(s)
Benzamides/chemical synthesis , Binding Sites , Proto-Oncogene Proteins pp60(c-src)/chemistry , src Homology Domains , Benzamides/chemistry , Crystallography, X-Ray , Drug Design , Phosphorylation , Structure-Activity Relationship
13.
J Med Chem ; 42(20): 4088-98, 1999 Oct 07.
Article in English | MEDLINE | ID: mdl-10514279

ABSTRACT

A series of 1,2,4-oxadiazole analogues has been shown to be potent and selective SH2 inhibitors of the tyrosine kinase ZAP-70, a potential therapeutic target for immune suppression. These compounds typically are 200-400-fold more potent than the native, monophosphorylated tetrapeptide sequences. When compared with the high-affinity zeta-1-ITAM peptide (Ac-NQL-pYNELNLGRREE-pYDVLD-NH(2), wherein pY refers to phosphotyrosine) some of the best 1,2, 4-oxadiazole analogues are approximately 1 order of magnitude less active. This series of compounds displays an unprecedented level of selectivity over the closely related tyrosine kinase Syk, as well as other SH2-containing proteins such as Src and Grb2. Gel shift studies using a protein construct consisting only of C-terminal ZAP-70 SH2 demonstrate that these compounds can effectively engage this particular SH2 domain.


Subject(s)
Enzyme Inhibitors/chemical synthesis , Oxadiazoles/chemical synthesis , Protein-Tyrosine Kinases/antagonists & inhibitors , src Homology Domains , Enzyme Inhibitors/chemistry , Enzyme Precursors/antagonists & inhibitors , Intracellular Signaling Peptides and Proteins , Models, Molecular , Oxadiazoles/chemistry , Structure-Activity Relationship , Syk Kinase , ZAP-70 Protein-Tyrosine Kinase
14.
J Biol Chem ; 273(20): 12325-31, 1998 May 15.
Article in English | MEDLINE | ID: mdl-9575185

ABSTRACT

As long as the threat of human immunodeficiency virus (HIV) protease drug resistance still exists, there will be a need for more potent antiretroviral agents. We have therefore determined the crystal structures of HIV-1 protease in complex with six cyclic urea inhibitors: XK216, XK263, DMP323, DMP450, XV638, and SD146, in an attempt to identify 1) the key interactions responsible for their high potency and 2) new interactions that might improve their therapeutic benefit. The structures reveal that the preorganized, C2 symmetric scaffolds of the inhibitors are anchored in the active site of the protease by six hydrogen bonds and that their P1 and P2 substituents participate in extensive van der Waals interactions and hydrogen bonds. Because all of our inhibitors possess benzyl groups at P1 and P1', their relative binding affinities are modulated by the extent of their P2 interactions, e.g. XK216, the least potent inhibitor (Ki (inhibition constant) = 4.70 nM), possesses the smallest P2 and the lowest number of P2-S2 interactions; whereas SD146, the most potent inhibitor (Ki = 0.02 nM), contains a benzimidazolylbenzamide at P2 and participates in fourteen hydrogen bonds and approximately 200 van der Waals interactions. This analysis identifies the strongest interactions between the protease and the inhibitors, suggests ways to improve potency by building into the S2 subsite, and reveals how conformational changes and unique features of the viral protease increase the binding affinity of HIV protease inhibitors.


Subject(s)
Anti-HIV Agents/chemistry , HIV Protease Inhibitors/chemistry , HIV Protease/chemistry , Azepines/chemistry , HIV-1/enzymology , Hydrogen Bonding , Molecular Conformation , Urea/analogs & derivatives , Urea/chemistry , Urea/pharmacology
15.
J Med Chem ; 41(9): 1446-55, 1998 Apr 23.
Article in English | MEDLINE | ID: mdl-9554878

ABSTRACT

Comparison of the high-resolution X-ray structures of the native HIV-1 protease and its complexes with the inhibitors suggested that the enzyme flaps are flexible. The movement at the tip of the flaps could be as large as 7 A. On the basis of this observation, cyclic cyanoguanidines have been designed, synthesized, and evaluated as HIV-1 protease (PR) inhibitors. Cyclic cyanoguanidines were found to be very potent inhibitors of HIV-1 protease. The choice of cyclic cyanoguanidines over cyclic guanidines was based on the reduced basicity of the former. X-ray structure studies of the HIV PR complex with cyclic cyanoguanidine demonstrated that in analogy to cyclic urea, cyclic cyanoguanidines also displace the unique structural water molecule. The structure-activity relationship of the cyclic cyanoguanidines is compared with that of the corresponding cyclic urea analogues. The differences in binding constants of the two series of compounds have been rationalized using high-resolution X-ray structure information.


Subject(s)
Anti-HIV Agents , Guanidines , HIV Protease Inhibitors , HIV Protease/metabolism , HIV-1/drug effects , Anti-HIV Agents/chemical synthesis , Anti-HIV Agents/chemistry , Anti-HIV Agents/metabolism , Anti-HIV Agents/pharmacology , Cell Line , Crystallography, X-Ray , Guanidines/chemical synthesis , Guanidines/chemistry , Guanidines/metabolism , Guanidines/pharmacology , HIV Protease/chemistry , HIV Protease Inhibitors/chemical synthesis , HIV Protease Inhibitors/chemistry , HIV Protease Inhibitors/metabolism , HIV Protease Inhibitors/pharmacology , HIV-1/enzymology , Humans , Hydrogen Bonding , Models, Molecular , Structure-Activity Relationship , Urea/analogs & derivatives , Urea/chemistry
16.
J Med Chem ; 39(18): 3514-25, 1996 Aug 30.
Article in English | MEDLINE | ID: mdl-8784449

ABSTRACT

High-resolution X-ray structures of the complexes of HIV-1 protease (HIV-1PR) with peptidomimetic inhibitors reveal the presence of a structural water molecule which is hydrogen bonded to both the mobile flaps of the enzyme and the two carbonyls flanking the transition-state mimic of the inhibitors. Using the structure-activity relationships of C2-symmetric diol inhibitors, computed-aided drug design tools, and first principles, we designed and synthesized a novel class of cyclic ureas that incorporates this structural water and preorganizes the side chain residues into optimum binding conformations. Conformational analysis suggested a preference for pseudodiaxial benzylic and pseudodiequatorial hydroxyl substituents and an enantiomeric preference for the RSSR stereochemistry. The X-ray and solution NMR structure of the complex of HIV-1PR and one such cyclic urea, DMP323, confirmed the displacement of the structural water. Additionally, the bound and "unbound" (small-molecule X-ray) ligands have similar conformations. The high degree of preorganization, the complementarity, and the entropic gain of water displacement are proposed to explain the high affinity of these small molecules for the enzyme. The small size probably contributes to the observed good oral bioavailability in animals. Extensive structure-based optimization of the side chains that fill the S2 and S2' pockets of the enzyme resulted in DMP323, which was studied in phase I clinical trials but found to suffer from variable pharmacokinetics in man. This report details the synthesis, conformational analysis, structure-activity relationships, and molecular recognition of this series of C2-symmetry HIV-1PR inhibitors. An initial series of cyclic ureas containing nonsymmetric P2/P2' is also discussed.


Subject(s)
HIV Protease Inhibitors/chemical synthesis , Urea/chemical synthesis , Animals , HIV Protease Inhibitors/pharmacology , Humans , Molecular Conformation , Structure-Activity Relationship , Urea/chemistry , Urea/pharmacology
17.
Chem Biol ; 3(4): 301-14, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8807858

ABSTRACT

BACKGROUND: Effective HIV protease inhibitors must combine potency towards wild-type and mutant variants of HIV with oral bioavailability such that drug levels in relevant tissues continuously exceed that required for inhibition of virus replication. Computer-aided design led to the discovery of cyclic urea inhibitors of the HIV protease. We set out to improve the physical properties and oral bioavailability of these compounds. RESULTS: We have synthesized DMP 450 (bis-methanesulfonic acid salt), a water-soluble cyclic urea compound and a potent inhibitor of HIV replication in cell culture that also inhibits variants of HIV with single amino acid substitutions in the protease. DMP 450 is highly selective for HIV protease, consistent with displacement of the retrovirus-specific structural water molecule. Single doses of 10 mg kg-1 DMP 450 result in plasma levels in man in excess of that required to inhibit wild-type and several mutant HIVs. A plasmid-based, in vivo assay model suggests that maintenance of plasma levels of DMP 450 near the antiviral IC90 suppresses HIV protease activity in the animal. We did identify mutants that are resistant to DMP 450, however; multiple mutations within the protease gene caused a significant reduction in the antiviral response. CONCLUSIONS: DMP 450 is a significant advance within the cyclic urea class of HIV protease inhibitors due to its exceptional oral bioavailability. The data presented here suggest that an optimal cyclic urea will provide clinical benefit in treating AIDS if it combines favorable pharmacokinetics with potent activity against not only single mutants of HIV, but also multiply-mutant variants.


Subject(s)
Azepines/chemical synthesis , Azepines/pharmacology , HIV Protease Inhibitors/chemical synthesis , HIV Protease Inhibitors/pharmacology , HIV-1/enzymology , Urea/analogs & derivatives , Administration, Oral , Animals , Azepines/chemistry , Azepines/pharmacokinetics , Crystallography, X-Ray , Drug Resistance, Microbial/genetics , HIV Protease Inhibitors/chemistry , HIV Protease Inhibitors/pharmacokinetics , HIV-1/physiology , Humans , Infusions, Intravenous , Mice , Microscopy, Electron , Solubility , Urea/chemical synthesis , Urea/chemistry , Urea/pharmacokinetics , Urea/pharmacology , Virus Replication/drug effects
18.
Pharm Res ; 13(2): 227-33, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8932441

ABSTRACT

PURPOSE: The effects of structural modifications on the membrane permeability of angiotensin II (Ang II) receptor antagonists and the usefulness of in vitro and in situ intestinal absorption models in predicting in vivo absorption or bioavailability were investigated. METHODS: Intestinal permeability was determined in vitro using Caco-2 cell monolayers and in situ using a perfused rat intestine method. Several physicochemical parameters were either measured or computed, and correlated with intestinal permeation. RESULTS: Permeation coefficients (Pa) across Caco-2 cell monolayers correlated well with both in situ absorption rate constants (ka) and in vivo bioavailability or % absorption. For these Ang II antagonists, Pa values larger than 3 x 10(-6) cm sec-1 and in situ ka values of 2 x 10(-4) min-1 cm-1 or above were associated with good in vivo absorption. Structural modifications at the R5 position, where a COOH group was substituted with either a CHO or CH2OH group, enhanced the permeability of the Ang II receptor antagonists up to 100-fold. There were good correlations between permeability and log P(octanol/buffer), log PHPLC, charge, solvation/desolvation energy and assigned hydrogen bonding potential. CONCLUSIONS: The correlations obtained in this study indicate that both the Caco-2 cell model and the in situ perfused rat intestine could be used to predict intestinal absorption in vivo. Structural modifications of the Ang II antagonists had a significant impact on the intestinal permeability. Charge, solvation energy, and hydrogen bonding are predominant determinants of intestinal permeability and oral bioavailability of these compounds.


Subject(s)
Angiotensin Receptor Antagonists , Indoles/pharmacokinetics , Intestinal Absorption/physiology , Mesylates/pharmacokinetics , Peptides, Cyclic/pharmacokinetics , Pyridines/pharmacokinetics , Tetrazoles/pharmacokinetics , Animals , Biological Availability , Biphenyl Compounds/chemistry , Biphenyl Compounds/pharmacokinetics , Caco-2 Cells/metabolism , Cell Membrane Permeability/physiology , Chemical Phenomena , Chemistry, Physical , Chromatography, High Pressure Liquid , Humans , Hydrogen-Ion Concentration , Imidazoles/chemistry , Imidazoles/pharmacokinetics , In Vitro Techniques , Indoles/chemistry , Losartan , Male , Mesylates/chemistry , Octanols/chemistry , Peptides, Cyclic/chemistry , Pyridines/chemistry , Rats , Rats, Sprague-Dawley , Solubility , Structure-Activity Relationship , Tetrazoles/chemistry
19.
Science ; 263(5145): 380-4, 1994 Jan 21.
Article in English | MEDLINE | ID: mdl-8278812

ABSTRACT

Mechanistic information and structure-based design methods have been used to design a series of nonpeptide cyclic ureas that are potent inhibitors of human immunodeficiency virus (HIV) protease and HIV replication. A fundamental feature of these inhibitors is the cyclic urea carbonyl oxygen that mimics the hydrogen-bonding features of a key structural water molecule. The success of the design in both displacing and mimicking the structural water molecule was confirmed by x-ray crystallographic studies. Highly selective, preorganized inhibitors with relatively low molecular weight and high oral bioavailability were synthesized.


Subject(s)
Azepines/chemistry , Drug Design , HIV Protease Inhibitors/chemistry , Administration, Oral , Animals , Azepines/metabolism , Azepines/pharmacokinetics , Azepines/pharmacology , Binding Sites , Biological Availability , Cell Line , Crystallography, X-Ray , Dogs , Drug Evaluation, Preclinical , HIV Protease/chemistry , HIV Protease/metabolism , HIV Protease Inhibitors/metabolism , HIV Protease Inhibitors/pharmacokinetics , HIV Protease Inhibitors/pharmacology , HIV-1/drug effects , HIV-1/physiology , Hydrogen Bonding , Models, Molecular , Molecular Conformation , Molecular Weight , Rats , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Urea , Virus Replication/drug effects
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