Does Cidofovir increase human papillomavirus oncogenicity?

Cidofovir is a drug used to treat viral infections. In particular, it is used to treat recurrent respiratory papillomatosis (RRP) warts that are  caused by human papillomavirus (HPV) infection of the larynx.  Some years ago researchers propsed that Cidofovir many cause cancer formation in HPV-infected tissues. We have performed some experiments using short-term treatment with the drug that indicate that this is not true. We propose to  extend these obervations using longer term drug treatment with the aim to prove that Cidofovir remains a safe and effective drug for treating RRP.