Bridging the Gap: Conference Record [Abstract book, International Conference on AIDS (12th: 1998: Geneva, Switzerland)]

12th World AIDS Conference

Abstracts 41194-41198 781

Methods: During a follow-up of four years we studied lymphoproliferative
response to anti-CD3 monoclonal antibody (mAb) alone or with addition of
anti-CD28 mAb and to phytohaemoagglutinin (PHA) in correlation with percentage of CD3+/CD8+/CD28+ and CD8+/CD38+/CD45RO+ lymphocytes in thirty HIV-1
infected subjects before and after therapy with nucleoside reverse transcriptase
inhibitors and protease inhibitors.
Results: Anti-retroviral therapy caused an amelioration of response to anti-CD3
mAb and to PHA. Increase of anti-CD3 driven lymphoproliferation after addition
of anti-CD28 mAb was observed in all patients; however patients treated with
protease inhibitors showed also an increase of CD3+/CD8+/CD28+ lymphocytes. We did not observed a significant effect of therapy on percentage of
CD8+/CD38+/CD45RO lymphocytes.
Conclusion: Anti-retroviral therapy caused an increase of CD4+ cell number
and an amelioration of lymphocyte functionality. A reduction of the expression
of activation markers may be obtained by treating patients with high active
anti-retroviral therapy during acute HIV-1 infection.

411941

The Five-to-None Trial (Essai Cinq-a-Zero): Five
antiretrovirals combined during 6 months as first
treatment course for HIV-1 infected treatment-naive
patients

Jacques Leibowitch1, D. Mathez1, M. Elissalt2, A. Neumann3, A. Saimot2.
Cinqazero Treatment Group, Hopitaux de Paris/lie de France; 1Hopital Raymond
Poincare, 104 Blvd Raymond Poincare 92380 Garches; 2lmea-Hopital
Bichat-Claude Bernard, Paris; 3Hopital Pitie-Salpetriere, Paris, France
Objective: To improve antiviral efficacy over current combination therapies such
as to obtain > a three month virus-recurrence free period following the omission
of treatment at 6 months; assess tolerance to the regimen; establish proof of
concept for intermittent courses of effective treatment.
Background: 1) Near-immediate retroviral recurrence has been invariably associated with cessation of highly active antiviral therapy regimens (HAART). Also,
infective CD4+ cells remain detectable at low and stable frequencies for up to
36 months after initiation of HAART (D. Finzi; J Wong; Science, november 14,
1997; T. Chun, PNAS, november 21, 1997; our unpublished observations). Altogether, this suggests continuous low grade HIV-1 activity under current regimens
combining 3.4 drugs aimed at retroviral enzymes (RT, protease).
2) Patients promised to a life-long antiviral drug treatment are at risk for serious
drug-related side-effects, and/or waning compliance or efficacy.
Design: Phase 1/11 open label multi-centric clinical trial for antiviral-naive patients with established HIV-1 infections and plasma RNA copies >30,000/ml; each
patient's baseline as control.
Study Medication: Daily Saquinavir 600 mg x 2 +Ritonavir 200 mg +stavudine
30/40 mg x 2 +didanosine 300 mg + nevirapine 200 mg x 2, for 6 months;.
Efficacy and safety end-points: Plasma viral RNA copies (ultradirect Amplicor), infective blood cells frequencies (limiting dilution), cell-associated proviral
DNA copies blood CD4 cell counts, weekly (1 - 4), Then monthly (2-, 13) together
with standard biochemistry and hematology.
Results and Conclusions: 36 patients to be included byfebruary 28, 1998.
Incidence of viral undetectability at 1, 2, 3, 4 months under treatment, individual
patients' "2nd virological compartments", will be presented.
41195 Adefovir (PMEA) and PMPA show synergistic or additive
inhibition of HIV replication in vitro in combination with
other anti-HIV agents
Julie Cherrington, A.S. Mulato. Gilead Sciences, 333 Lakeside Drive Foster City
California 94404, USA
Background: Adefovir (PMEA), an acyclic nucleoside phosphonate analogue, is
active against retroviruses, hepadnaviruses and herpesviruses. Adefovir dipivoxil,
an orally bioavailable prodrug of adefovir, is currently in phase III clinical trials
for the treatment of HIV and phase II clinical trials for the treatment of HBV
infections. PMPA is a related acyclic nucleoside phosphonate analogue that has
demonstrated potent anti-SIV activity in rhesus macaques. Recently PMPA and
its orally bioavailable prodrug have also shown marked anti-HIV activity in phase
1/11 clinical studies. Since the standard of care for AIDS patients has become
combination therapy, the effects of other antiretroviral compounds on the anti-HIV
activity of adefovir and PMPA were investigated in vitro.
Methods: Drug combination experiments were performed in MT2 cells infected
with HIV Illb. The combined drug effects were analyzed using the method of
Prichard (MacSynergy; version 1).
Results: Adefovir and PMPA both demonstrated strong synergistic anti-HIV
activity in combination with AZT, 141W94, nevirapine and delavirdine. Adefovir demonstrated minor to moderate synergistic inhibition of HIV replication in
combination with PMPA, d4T, ddC, nelfinavir, ritonavir, and saquinavir. PMPA
demonstrated minor to moderate synergistic inhibition of HIV replication in combination with ddl and nelfinavir (and adefovir). Additive inhibition of HIV replication
was measured for adefovir in combination with 1592, 3TC, ddl, and indinavir as
well as for PMPA in combination with 1592, 3TC, d4T, ddC, indinavir, ritonavir
and saquinavir. Importantly, no antagonistic interactions were measured for any
of the adefovir or PMPA combinations.
Conclusions: Based on these in vitro results, adefovir and PMPA would both
be expected to function efficiently as part of a variety of combination regimens.
Furthermore, the combination of adefovir and PMPA would be predicted to result
in additive to synergistic inhibition of HIV replication.

41196 I Characterization of the anti-HIV properties, resistance
profile and safety of dOTC (2'-deoxy-3'-oxa-4'
thiocytidine)
Jean Bedard1, Terry Bowlin1, Mark Wainberg2, Tarek Mansour3, Stan Tyms4,
Patricia Williams1, Debra Taylor4, Caroline Fortier1. 1Biochem Therapeutic Inc.,
275 Armand Frappier, Laval, Quebec; 2McGill University AIDS Center, Montreal,
QC, Canada; 3 Wyeth-Ayerst, Pearl River, NY USA; 4MRC Collaborative Center,
Mill Hill, London, England, UK
dOTC is a member of a new class of heterosubstituted nucleoside analogs. We
have demonstrated that dOTC has potent in vitro activity against HIV-1. dOTC
was tested against various HIV-1 wild type laboratory-derived strains and clinical
isolates. The IC50 against wild-type viruses ranges from 0.1-0.3,/M. dOTC also
shows antiviral activity against HIV-1 clinical isolates resistant to 3TC", AZT,
saquinavir and indinavir. Studies assessing the efficacy of dOTC against genotyped HIV-1 clinical isolates resistant to multiple HIV therapies will be presented.
In addition, in vitro activity profiles of dOTC in drug combination studies with
other nucleoside analogs, non-nucleoside reverse transcriptase inhibitors and
protease inhibitors will also be shown. Resistance to dOTC (200 /1M) appears
to develop slowly: following 12 passages in MT-4 cells, no phenotypic resistance
has been observed and no mutation in the reverse transcriptase gene has been
detected. Experiments are underway to select HIV-1 viruses resistant to dOTC
using different cell lines. In vitro experiments and animal toxicity data revealed
that dOTC exhibits a good safety profile. Cytotoxicity evaluation in twelve different
cell lines demonstrated that dOTC has an IC50 > 100 /M cell growth. Oral doses,
up to 500 mg/kg/day, in rats and 1000 mg/kg/day in monkeys were well tolerated.
dOTC is present in the cerebrospinal fluid of rats in concentrations higher than
3TC and AZT following oral administration (5 mg/kg) of each drug.
The safety, efficacy and resistance profile of dOTC support its potential for
clinical development.
41197 Purification and characterization of an anti-HIV substance
from Perilla frutescens Britton, mint plant
Shuichi Oka1, Y. Fukumori2, Y. Sapporo1, Y. Yamazaki1, T. Kawahata3,
T. Otake3, H. Mori3, Y. Izumoto3, I. Oishi3. 'Natl. Inst. Biosci. Human-Tech.,
Higashi 1-1, Tsukuba, Ibaraki; 2Hokuren Fed. Agric. Coop., Sapporo; 3Osaka
Prefec. Inst. of Public Health, Osaka, Japan
Objectives: We previously reported that extracts from many plants of mint family
have anti-HIV activity. The present study was aimed to purify and characterize
the anti-HIV component from the hot water extract of mint plant, Perilla frutescens
Britton (green perilla).
Methods: Perilla leaves were boiled for 15 min. The extract was filtered and
precipitated with the addition of cetylpyridinium chloride, precipitant for polysaccharide. The active substance was further purified by column chromatography on
DEAE-Toyopearl and hyaluronidase-immobilized Toyopearl.
Results: The purified substance was identified as a glycoprotein with a molecular weight of 6-kDa on SDS-PAGE, and had an inhibitory activity on degranuration
of mast cells. The inhibitory activity of this substance (ICso) for replication of
HIV-1 strains, LAI, RF and KK-1 and a HIV-2 strain of LAV-2ROD were 2.6, 4.3,
4.5 and 7.8 pg/mL, respectively, which were almost the same or higher than
the anti-HIV activity of dextran sulfate 8000. The concentration for cell growth
inhibition (CCso) for MT-4 cells was 250 /~g/mL. The substance also inhibited
replication of both strains KK-1 in PBMC and JR-FL, macrophage-tropic HIV-1
strain, in macrophages. This substance further inhibited HIV-1-induced giant cell
formation (IC50o: 6.4 /rg/mL) and HIV-1 reverse transcriptase activity (IC50o: 0.34
/ig/mL). The infectious titer of HIV-1 decreased by one logo after the virus had
been exposed at the concentration of >2 tpg/mL. Furthermore, this substance
did not inhibit binding of anti-Leu3a antibody to MT-4 cells, but it blocked binding
of 0.5 f/, a monoclonal antibody against V3 of gp120, to the surface of HIV-1
infected cells, suggesting that this substance exhibits anti-HIV activity by affecting
the virus envelope.
Conclusion: These findings indicate that the glycoprotein from the hot water
extract of Perilla frutescens Britton acts on the step of virus binding and fusion
with cells.
41198 Development and characterization of HIV-1 resistant to
modified cyclodextrin sulfate (mCDS) 71 in vitro
Haruyo Moril, T. Otake', T. Kawahatal, Y. Izumotol, I. Oishi', T. Kurimura2.
10Osaka Prefectural Institute of Public Health, 1-3-69 Nakamichi, Higashinari-ku,
Osaka; 2Research Institute for Microbial Diseases, Osaka, Japan
Objectives: To identify the target site of modified cyclodextrin sulfate (mCDS)
71, a new polyanionic anti-HIV agent which action mechanism is considered to
be the blockage of virus binding to the target cells.
Methods: Resistant HIV-1 strains to mCDS71 were developed by serial passage of the HIV-1 infectious clone pNL432, a clinical isolate KK-1 and an

AZT-resistance A018 in MT-4 cells in the presence of gradually increasing concentrations of the compound. The resistant phenotypes were determined by
biological assay using MT-4 cells. The gp120-V3C6 genes of resistant strains
were amplified by PCR and analyzed genetically.
Results: The mCDS71-resistant strains were obtained after 22 to 40 passages
in MT-4 cells, with 43- to 154-fold increase in the IC50s compared with that of each
parental virus. Moreover, mCDS71-resistant strains showed cross-resistances to
dextran sulfate. Sequencing of the gp120-V3C6 genes of the resistant strains