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. 1987 Feb;31(2):187–190. doi: 10.1128/aac.31.2.187

Roxithromycin (RU 965): effective therapy for experimental syphilis infection in rabbits.

S A Lukehart, S A Baker-Zander
PMCID: PMC174689  PMID: 3551828

Abstract

Roxithromycin (RU 965), a new macrolide antibiotic, was shown to be effective for therapy of active syphilis in rabbits. Dark-field-positive lesions were produced in adult male rabbits by intradermal inoculation of approximately 10(6) Treponema pallidum organisms at each of 11 sites. Beginning 7 days after infection, six animals per group were treated with benzathine penicillin G (200,000 U, intramuscularly, weekly for 2 weeks) or roxithromycin (15 mg/kg of body weight, orally, twice daily for 15 days); six animals were not treated. Chancres in untreated animals were dark-field positive throughout the 16-day observation period; all benzathine penicillin-treated rabbits were dark-field negative 1 day after the initiation of therapy. Five of six animals treated with roxithromycin were dark-field negative on day 3 following the initiation of therapy; the sixth animal was dark-field negative by day 6. Lesions in untreated animals reached a mean (+/- standard deviation) maximum diameter of 14.7 +/- 1.91 mm compared with 8.4 +/- 3.6 mm for benzathine penicillin-treated (P less than 0.005) and 10.4 +/- 1.2 mm for roxithromycin-treated (P less than 0.001) animals. Ulceration occurred at 62 of 66 lesions in untreated animals compared with 0 of 66 lesions in each treated group. At 3, 6, and 12 weeks postinfection, Venereal Disease Research Laboratory antibody titers were significantly higher (P less than 0.05) in untreated than in treated animals. Titers in penicillin-treated versus roxithromycin-treated animals were significantly different at 6 weeks postinfection but not at 3 and 12 weeks postinfection. Transfer of tissue from treated rabbits to seronegative recipient animals did not reveal any evidence of persistent infection in the benzathine penicillin- or roxithromycin-treated animals. These findings indicate that benzathine penicillin and roxithromycin, at the doses indicated above, are effective in treating active syphilis in rabbit model.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Baughn R. E., Musher D. M., Adams C. B., Knox J. M. Evaluation of rosaramicin phosphate in treatment of experimental syphilis in rabbits. Antimicrob Agents Chemother. 1981 Jan;19(1):117–121. doi: 10.1128/aac.19.1.117. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Brown S. T. Treatment of secondary syphilis. J Am Vener Dis Assoc. 1976 Dec;3(2 Pt 2):136–142. [PubMed] [Google Scholar]
  3. CLARK J. W., Jr, YOBS A. R. EFFECT OF ACTINOSPECTACIN IN EXPERIMENTAL SYPHILIS IN THE RABBIT. I. EARLY LESION SYPHILIS. Br J Vener Dis. 1963 Sep;39:184–189. doi: 10.1136/sti.39.3.184. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Dunham W. B., Rake G. The Activity of Streptomycin in Experimental Syphilis. Science. 1946 Mar 22;103(2673):365–365. doi: 10.1126/science.103.2673.365. [DOI] [PubMed] [Google Scholar]
  5. Elliott W. C. Treatment of primary syphilis. J Am Vener Dis Assoc. 1976 Dec;3(2 Pt 2):128–135. [PubMed] [Google Scholar]
  6. Hashisaki P., Wertzberger G. G., Conrad G. L., Nichols C. R. Erythromycin failure in the treatment of syphilis in a pregnant woman. Sex Transm Dis. 1983 Jan-Mar;10(1):36–38. doi: 10.1097/00007435-198301000-00008. [DOI] [PubMed] [Google Scholar]
  7. Kuwahara S., Zenyoji H. Cephaloridine treatment of experimental rabbit syphilis. Postgrad Med J. 1967 Aug;43(Suppl):130–133. [PubMed] [Google Scholar]
  8. Lukehart S. A., Baker-Zander S. A., Holmes K. K. Efficacy of aztreonam in treatment of experimental syphilis in rabbits. Antimicrob Agents Chemother. 1984 Mar;25(3):390–391. doi: 10.1128/aac.25.3.390. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Lukehart S. A., Baker-Zander S. A., Sell S. Characterization of lymphocyte responsiveness in early experimental syphilis. I. In vitro response to mitogens and Treponema pallidum antigens. J Immunol. 1980 Jan;124(1):454–460. [PubMed] [Google Scholar]
  10. Schroeter A. L., Lucas J. B., Price E. V., Falcone V. H. Treatment for early syphilis and reactivity of serologic tests. JAMA. 1972 Jul 31;221(5):471–476. [PubMed] [Google Scholar]
  11. Thompson S. E., 3rd Treatment of syphilis in pregnancy. J Am Vener Dis Assoc. 1976 Dec;3(2 Pt 2):158–167. [PubMed] [Google Scholar]

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