Squamous Papilloma of the Larynx Clinical Trial
Official title:
Phase IIIb Study of Recombinant Tetravalent HPV Vaccine in Patients With Recurrent Respiratory Papillomatosis
Vaccines against human papillomaviruses are now commercially available. One of the commercial vaccine contains antigens of both LR HPV types which cause virtually all cases of RRP. Clinical trials have documented the safety and immunogenicity of this vaccine as well as its effectiveness in prevention of incident and persistent infection of the vaccinal types as well as a development of lesions caused by these types. After vaccination the antibodies level increases dramatically and the high levels of antibodies are present in the blood still after 6 years. Furthermore, the neutralization antibodies to the vaccinal antigens have been detected in the cervical mucus of vaccinated women. The preliminary data are now available showing the presence of HPV-specific antibodies in the oral cavity in women after vaccination. The level of antibodies has been dependent on time since vaccination.
In our previous studies we have documented that in patients with RRP the level of HPV-specific antibodies is low and increases only after numerous surgery procedures. Therefore the application of this vaccine to patients with RRP can stimulate increased level of antibodies in the blood as well as presence of virus-specific neutralization antibodies on the surface of upper aero digestive tract and neutralize viruses shed from new papillomas and in this way protect patient from spreading of the infection as well as to facilitate the decrease of load of infectious virus shed from the lesion. This can possibly lead to the inhibition of growth of the papillomatous lesion. ;