Human papillomavirus infection and therapy with interferon

In vivo sustained dermal delivery and pharmacokinetics of interferon alpha in biphasic vesicles after topical application

Biphasic vesicles, a novel nanostructured lipid-based delivery system show potential for topical application of interferon alpha (IFN α) for the treatment of human papillomavirus (HPV) infections (anogenital warts). Dermal delivery of IFN α encapsulated in biphasic vesicles (BPV-IFN α), applied topically to the skin, was characterized in a guinea pig model. BPV-IFN α (1g, 2 MIU/g) was topically applied either as a single or multiple treatments on the skin of guinea pigs. As a comparison with currently used regimens, IFN α solution was administered intravenously or intradermally. Skin and serum samples were collected over 96 h, IFN α levels were determined by an antiviral assay, and half-life (t₁/₂) and elimination (k) rates were calculated. Topical BPV-IFN α treatment resulted in maximum skin levels (about 100,000 U/100 cm(2)) of IFN α within 6h and maintained for 72-96 h. Clearance from the skin after intradermal injections was initially fast (t₁/₂ 0.62 h, k 1.1179 h(-1)), followed by a slower steady decrease after 6h. After intravenous and intradermal administration, IFN α was rapidly cleared from the serum, t₁/₂ 0.75 h, k 0.9271 h(-1) and t₁/₂ 1.28 h, k 0.5421 h(-1), respectively, whereas after topical application, IFN α levels remained below 100 U/mL. Topical application of BPV- IFN α resulted in sustained delivery of biologically active IFN α locally into skin with minimal systemic exposure.

Successful treatment of recurrent vulvar intraepithelial neoplasia resistant to interferon and isotretinoin with cidofovir

Vulvar intraepithelial neoplasias are difficult to eradicate completely without extensive surgical intervention. Cidofovir, a deoxycytidine monophosphate analog, may have a therapeutic role in this disease. A 43-year-old woman with a 20-year history of genital warts presented with extensive vulvar intraepithelial neoplasia III, and refused surgical resection. Topical cidofovir 1% in Beeler base completely eradicated the lesion. Successive treatment applications, however, were necessary. Cidofovir is a promising topical antiviral compound for HPV induced vulvar intraepithelial neoplasia.

5-aminolevulinic acid-mediated photodynamic therapy of intraepithelial neoplasia and human papillomavirus of the uterine cervix--a new experimental approach

The aim of this study was to treat patients for ectocervical dysplasia [cervical intraepithelial neoplasia (CIN) grades 1 and 2] and associated human papilloma virus (HPV) infections with photodynamic therapy (PDT). In 20 patients, 5-aminolevulinic acid (5-ALA, 12% w/v) was applied topically with a cervical cap 8 h prior to illumination. A thermal light source (150 W halogen lamp) emitting a broadband red light (total energy: 100 J/cm2, fluence rate: 90 mW/cm2) was used for superficial illumination of the portio. In addition, an Nd:YAG pumped dye laser (652 nm) was used to illuminate the cervical canal (total energy: 50 J/cm2, fluence rate: 300 mW/cm2). Preliminary results of follow-ups at 1, 3, 6, and 9 months posttherapy showed a cytological improvement in the grading of the PAP smears in 19 patients and the eradication of cervical HPV in 80%. These results demonstrate that ectocervical dysplasia and associated HPV infections can be treated by PDT.